The Asian Forum for Accelerators and Detectors (AFAD) in 2021 will be organized by Budker Institute of Nuclear Physics (BINP) in Novosibirsk, Russia. AFADs are held annually under the guidance of Asian Committee for Future Accelerators (ACFA) to promote collaboration among universities and research institutes in Asia and Oceania.
The major topics (working groups) of the Forum are:
WG1: Accelerator and its related technologies for photon science
WG2: Detector technology development
WG3: Accelerator technologies for industrial & medical applications
WG4: Innovative accelerator techniques
WG5: Accelerator and its related technologies for hadron (neutron) science
WG6: Network & computing
WG7: Cryogenics, cryomodule and superconducting technology for accelerators
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This will be a pre-recorded talk.
Status and results of experiments CMD-3 and SND at VEPP-2000 collider and KEDR at VEPP-4M collider at BINP will be presented. Status of the Super Charm-Tau Factory project will be discussed.
A new heavy ion accelerator, called RAON (Rare isotope Accelerator complex for ONline experiments) has been built in Korea. Two isotope production systems (ISOL and IF) are being assembled and a fully superconducting linear accelerator are under construction for the driver and the post accelerator. Recent progress of the project will be presented with future plan.
The Circular Electron-Positron Collider (CEPC) study group currently focuses on the Technical Design Report (TDR) of the accelerator, the R&D of the key components of the machine and the detector, the general software framework, and site investigation. Meanwhile the group is planning further R&D and validations. In this presentation the status and the progress of the CEPC will be reported.
To carry out experiments on X-ray flash radiography, a high power linear induction accelerator (LIA) was developed at the Budker Institute of Nuclear Physics. This report describes the main systems of the accelerator and its main parameters. The results of modeling the beam dynamics in the injector and linear accelerator are presented. The simulation is compared to the experimental data. An important aspect of the transverse beam dynamics in this type of accelerators is the presence of beam break up instability (BBU), thus, special attention is paid to the methods of mitigation of BBU and results of such mitigation are presented. A prospective area of application of high-current electron beams with high brightness, created in the LIA, is the generation a terahertz radiation flux in frame of the scheme of a free electron laser (FEL). The issue of using a beam from LIA to generate terahertz radiation is discussed, and the required beam parameters to obtain effective radiation generation are specified.
Shanghai soft X-ray Free-Electron Laser facility (SXFEL) is being developed in two steps, the test facility SXFEL-TF and the user facility SXFEL-UF. The SXFEL-TF, which is able to generate 8.8 nm FEL radiation with the two-stage cascaded HGHG-HGHG or EEHG-HGHG scheme, passed the national acceptance in Nov. 2020. Commissioning progress and results of the SXFEL-TF will be introduced in this presentation.
The Australian synchrotron has recently completed a conceptual design for upgrading the facility to a 4th generation light source.This talk will outline the design options that were explored and the proposed benefits for the facility.
Small-scale accelerator-based radiation sources have been used for developing advanced technologies and exploring new science with high convenience and low cost. We have developed a 3 MeV ultrafast electron diffraction (UED) probe technology that nominally reduces the electron bunch duration and the arrival time jitter to the sub-femtosecond level. This simple configuration uses a radiofrequency photogun and a 90° achromatic bend and is designed to provide effectively jitter-free conditions. THz streaking measurements reveal an electron bunch duration of 25 fs, even for a charge as high as 0.6 pC, and an arrival time jitter of 7.8 fs, the latter limited only by the measurement accuracy. From pump-probe measurements of photoexcited bismuth films, the instrument response function was determined to 31 fs. Recently, we proposed a simple way to further compress the electron bunch duration to sub-10 fs based on installing an energy filter in the dispersion section of the achromatic bend. Through numerical simulations, we demonstrate that the electron bunches can be compressed, at the sample position, to a 6.2 fs duration for a 100 fC charge. This result suggests that the energy filtering approach is more viable and effective than complicated beam-shaping techniques that commonly handle the nonlinear distribution of the electron beam.
In an attempt to design smaller THz free-electron laser (FEL) devices capable of producing higher output powers in the THz spectral region of 1-2 THz, we have developed a microtron accelerator that can accelerate electron beams from 3-6 MeV, with a measured macropulse current of more than 40 mA. The new THz FELs use hybrid electromagnetic (EM) undulators that are two to four times shorter in length than the previous 2-m-long undulator and waveguide resonators with mode cross-sectional areas that are more than two times smaller than the parallel-plate waveguide in the existing FEL. We confirm that the gains and losses of the more compact FELs are sufficient for lasing, and we estimate that an average output power of approximately 1 W is possible with an efficiency approximately 10 times greater than the existing FEL. The minimum size of the THz FEL system, including a high-voltage pulse modulator, is estimated to be approximately 1.5 m × 2.0 m.
An Infrared Free Electron Laser (IR-FEL) has been built at RRCAT, Indore to serve as a user facility for the optical spectroscopy of materials in low temperature and high magnetic field environment. The first commissioning experiments on the IR-FEL setup were performed in 2016 with an injector system built in-house. The first observation of lasing using this setup was made in November 2016, but the achieved out-coupled power was two to three orders of magnitude lower as compared to the saturated out-coupled power predicted by the FEL design simulations. The setup has recently undergone a major upgrade with the installation and commissioning of a new injector system, and saturation of lasing at a wavelength of 28 m has been observed in March 2020, which is the first lasing of a FEL in India. The maximum measured Continuous Wave (CW) out-coupled power is 7.3 mW, which is in a reasonably good agreement with predictions of the FEL simulations considering the experimental electron beam parameters. Efforts are presently underway to achieve out-coupled CW average power greater than 125 mW by increasing the duty cycle of the injector system.
Hyper-Kamiokande is an international collaboration as a leading worldwide experiment to address fundamental unresolved questions in particle physics and cosmology. The project includes the construction of Hyper-Kamiokande detector, J-PARC beam upgrade, and the near detector upgrade/construction. Many physics opportunities are available; CP violation and neutrino mass ordering, a search for proton decay predicted by Grand Unified Theories (GUTs), and neutrino astrophysics from the astronomical objects such as solar, supernova, etc. The budge of the project was approved in Japan in 2020, and we had the first construction year. Several R&Ds are actively ongoing toward production and construction. In the talk Hyper-Kamiokande project is overviewed and the project status will be explained.
The Jiangmen Underground Neutrino Observatory(JUNO) is a next-generation neutrino experiment located 700m underground in Southern China. The detector will use a 20 kton liquid scintillator equipped with 17612 20-inch PMTs and 25600 3-inch PMTs, with the photocathode coverage reaching ~78%. The detector is designed to reach a high energy resolution of 3% at 1 MeV for neutrino mass ordering(MO) determination. Outside the central detector, the pool is filled with ultrapure water equipped with 2400 MCP PMTs as a veto system for cosmic muon detection. There is a top tracker on top of the water pool to determine the muon track. JUNO will measure the neutrino MO (3∼4σ) and the three neutrino oscillation parameters to the sub-percent level. JUNO also has a rich physics potential for supernova neutrinos, geo-neutrinos, solar neutrinos, and searching for new physics beyond the Standard Model. The subsystem development and production programs are well underway. This talk will mainly focus on the status of the JUNO experiment.
A new technique for ion identification in Accelerator Mass Spectrometry (AMS) has been proposed by measuring the ion track ranges using a low-pressure TPC. As a proof of principle, a low-pressure TPC with charge readout using a THGEM multiplier was developed. The tracks of alpha particles from various radioactive sources were successfully recorded in the TPC. The track ranges were measured with a high accuracy, reaching the 2% resolution level. Using these results and the SRIM code simulation, it is shown that the isobaric boron and beryllium ions can be effectively separated at ten sigma level. It is expected that this technique will be applied in the AMS facility in Novosibirsk for dating geological objects, in particular for the geochronology of Cenozoic Era.
Search for neutrinoless double beta decay (0νββ) is a key experiment to answer unresolved properties of neutrino. Experimental observation of 0νββ will provide a direct answer to the particle type of neutrino (i.e., the Dirac-or-Majorana question), validate lepton number violation in the field of particle physics, and confine the absolute mass scale of neutrino. A number of large scale experiments have been searching, and are planned to search for 0νββ. Low-temperature thermal calorimeters based on thermal calorimetric measurement have been playing a major role in the effort to probe the rare event. In the presentation, current 0νββ search experiments are introduced with their main detection technologies. Advantages and challenges using the detector technologies are discussed in comparison with other technologies used for 0νββ. Moreover, I will present the prospective and recent progress of AMoRE double beta decay experiment.
The GEM detector is useful for various fields, not only high energy physics. But, one uncomfortable feature is to be broken due to a large discharge. One large charge deposit makes a trigger to lead the large discharge and to carbonize inside the GEM hole. In order to avoid such a bad situation, we are developing new GEM foil without carbon. One good solution is to apply ceramic as an insulator instead of Polyamide and Liquid Crystal Polymer (LCP). New ceramic GEM was manufactured with 100 mm × 100 mm size and 100 m thickness. Also, a neutron detector was constructed with a hybrid cathode to detect both thermal (or cold) neutron and MeV neutron. The hybrid cathode consists 0.5mm PET (Polyethylene Terephthalate) plate with 1 m boron layer. Thermal neutron can be absorbed in the boron layer and can produce alpha particle (and Li nuclei). The cross section of boron for the MeV neutron is too small. It is better to select another material to detect the MeV neutron. The MeV neutron can easily hit the hydron inside of material and can produce the proton. On good candidate is PET, which contents large amount of hydrogen. The cathode was fabricated by ourself and installed in the chamber with single GEM structure. The chamber is work fine. Now, we are trying to make boron coated GEM to get higher efficiency for the thermal neutron. It will be available near future.
We are developing 1.5 cell SRF (Superconducting RF) 1.3GHz electron gun to realize the generation of high intensity electron beam for compact water purification system. In the first stage, we manufactured Nb 1.5 cell RF gun and tested it at 2K1). Next planned step is to generate Nb3Sn layers with thickness of a few um on the surface of Nb superconducting cavities for 4K operation. Then, we will research the performance of 4K Nb3Sn SRF electron gun with CW pulsed laser system.
Important research issues are the operation of 4K Nb3Sn SRF cavity, photo-cathode at 4K and the generation of high intensity electron beam. I will report the plan with many advantages over present utilized facilities by establishing the water purification project using the SRF electron gun2). It will take at least 5 years to establish the technologies with the budget which is requesting funding agencies now.
1) T. Konomi of KEK mainly made this study.
2) R. Varma of IITB in India mainly proposed this project around 2018.
The report describes a series of industrial accelerators of the ILU type with energy of 1-10 MeV, with a power of up to 100 kW for irradiating products in the electronic mode and in the X-ray bremsstrahlung mode.
High power electron linear accelerator (linac) is particularly useful and powerful tool for the RI production via photonuclear reaction, which has large cross-section in energy range from 10 MeV to 30 MeV (Giant resonance). For a photonuclear reaction, bremsstrahlung γ-rays is produced by an electron beam irradiating the target materials. At ELPH, we employ an S-band electron linac of which the maximum energy is 60 MeV and the average beam current is more than 100 μA. We are conducting research on medical radioactive isotope (RI) production such as 99Mo and 225Ac using the electron linac. The basic studies are being performed in collaboration with private companies, research institutes and universities. A part of collaborative research for medical RI production will be introduced in this presentation.
Single photon emission computed tomography is a medical diagnostic tool mainly used for cancer surveys. An image of the diseased part can be acquired using 141-keV gamma rays emitted from Tc-99m. Tc-99m has a half-life of 6 h and is the decay product of Mo-99. For long term sustainable production of Mo-99, the accelerator based system seems to be very promising.
The compact energy recovery linac (cERL) is a superconducting continuous wave electron accelerator. For Mo-99 production experiment, the maximum beam energy is 21 MeV and averaged beam current 10 μA limited by the radiation safety of the present facility configuration. The construction of the new beamline with the target system began in July 2018 and finished in March 2019. By Mo-99 production experiments at cERL, the spatial distribution of bremsstrahlung and the energy dependence of the yield in the target were precisely acquired. From generated Mo-99, Chiyoda Technol Corporation (CTC) successfully extracted Tc-99m at the RI Lab in KEK using both the alumina column generator method and solvent extraction method. By both methods, pure Tc-99m can be successfully extracted. Prototype facility model for the mass commercial production was already designed and the funding and construction will be the next step.
The beamline and target system are supported by Accelerator Inc. The research is a joint project with the CTC and FFTC (Fuji Film Toyama Chemical).
Recent progresses on the development of particle and photon sources from laser-wakefield accelerators at National Central University (NCU) will be presented in this talk. At NCU, a 100-TW multi-beam laser system and a joint experimental platform have been optimized for laser plasma acceleration. The current research focuses are compact high-quality laser wakefield accelerator (LWFA) and its derivative light sources.
Hard x-ray/gamma-ray emission from laser wakefield accelerator have a number of interesting applications, e.g. ultrafast dynamic probing of matter. Betatron radiation and Thomson scattering are highly collimated laser-driven hard x-ray/gamma-ray sources with fs duration which generated by electron transversely oscillation in wakefield or laser field. However, photon yield is always limited by electron charge which is controlled by beamloading effects during acceleration. So, we proposed several experiments to increase accelerated electron charge, such as double injection, ps laser driven, NCD targets etc. As a result, greatly improved radiation sources are archived in our experiments.
There are far fewer beam-driven wakefield accelerator experiments than laser-driven ones worldwide. This is mainly because there are far fewer facilities that can provide the high-current, high-quality electron beams that are required for such experiments. This is the same situation in Korea. Only recently, a full-scale research program on beam-driven wakefield took off. In this talk, we will present some simulation efforts lead by UNIST group, and experimental programs being planned in collaboration with Pohang Accelerator Laboratory (PAL).
Laser-plasma accelerators have been the most promising candidates for future compact accelerators which can be used for next-generation free-electron lasers (FELs). However, their poor stability and reproducibility limit the applications of the laser-plasma accelerator. PAL-ITF (injector test facility) has an S-band RF photocathode gun and final energy of 70 MeV, with a lower emittance, which can be used for the seed beam for advanced plasma accelerators. The electron beam from the RF photocathode gun should be matched with the wakefield focusing strength for the beta motion of the electron beam inside the wakefield for the external injection scheme. Therefore, the electron beam size should be decreased at the entrance of the plasma source for good matching, and for preserving the emittance, slowly increasing the plasma ramp is also required. We currently have been prepared the plasma lens experiments for focusing on the electron beam using the discharge capillary plasma source. We also developed the capillary source with a long ramp plasma for emittance matching. In this presentation, we present on-going advanced accelerators R&D plans at PAL-ITF.
The acceleration gradient of a solid-state accelerator is limited by the damage field to the structure material. A dielectric is therefore the choice of material for an accelerator operating at the optical frequencies. A dielectric laser accelerator has the potential of stable high-gradient electron acceleration over a long distance. Owing to the much shorter drive wavelength, a dielectric laser accelerator could also produce very short electron bunches useful for studying attosecond science or generating EUV superradiance. The inverse process of particle acceleration is particle radiation. In this presentation, we will show various mechanisms to generate laser-like radiation from a beam-driven dielectric structure by a small account of charge. The coherent radiation by itself is useful for applications. We will show experimental effort toward realizing such a few-electron driven free-electron laser.
Microbeams of the ionization radiation are widely used in the scientific and industrial fields. If the size of the microbeam system is as small as the several-tens keV class electron microscope, it will be possible to perform the radiobiology experiments in university-class laboratories. Since a laser dielectric acceleration system (DLA) has the potential to realize an on-chip accelerator, the research and development of DLAs has been conducted. The required charge in a bunch (pulse) is as small as 0.02fC for observing a radiation effect in a biological cell. The beam energy and the beam size are in the range of 0.5-1 MeV and several hundred nano-meters, respectively.
In the Budker Institute of Nuclear Physics an accelerator based epithermal neutron source was proposed and designed to the development of the perspective cancer treatment, which is the Boron Neutron Capture Therapy. The source consists of a vacuum-insulated tandem accelerator, which produces a 2MeV proton or deuterium beam, a lithium target in which neutrons are generated in the 7 Li(p, n)7 Be threshold reaction and beam shaping assembly (BSA) which forms a neutron beam An epithermal-neutron beam suitable for boron neutron capture therapy was obtained and successful biological studies were carried out with the source. To generate a powerful flux of fast neutrons, we use the reaction Li (d,n), The operating mode with the deuteron beam is attractive for radiation testing of materials, fast neutron therapy, and other applications. At proton energies below the neutron generation threshold, the reaction of inelastic proton scattering by lithium can be used to generate a monochromatic 478 keV line. The report gives a description of the neutron source and the results obtained at the facility
The new compact accelerator-based neutron facility AISTANS at the National Institute of Advanced Industrial Science and Technology in Japan was constructed. AISTANS is providing a pulsed neutron beam from a decoupled solid methane moderator from 2020. In this presentation, overview of AISTANS and a recent neutron flux measurement result at AISTANS will be presented.
China Spallation Neutron Source (CSNS) accelerator complex consists of a front end, an 80MeV DTL LINAC, and a 1.6GeV Rapid Cycling Synchrotron (RCS). It is designed with a beam power of 100kW in the first phase and reserves upgrade capability to 500kW in the second phase. CSNS has started user operation at 20kW after the initial beam commissioning in 2018, the beam power is quickly up to 50kW and 80kW by two times beam commissioning in between the user beam time 2019, and finally reached 100kW, the design goal, in February 2020. This talk gives the experiences and most recent status of beam instrumentation system of CSNS during the beam power ramping.
The China Spallation Neutron Source (CSNS) is an accelerator-based science facility. CSNS is designed to accelerate proton beam pulses to 1.6 GeV kinetic energy, striking a solid metal target to produce spallation neutrons. CSNS has two major accelerator systems, a linear accelerator (80 MeV Linac) and a 1.6 GeV rapid cycling synchrotron (RCS). The RCS accumulates and accelerates the proton beam to 1.6 GeV and then extracts the beam to the target at the repetition rate of 25 Hz. The Beam commissioning of CSNS/RCS had been started since April 2017. At the end of February 2020, CSNS reached the design beam power of 100-kW with very low uncontrolled beam loss. The most important issue in high-intensity beam commissioning is the beam loss control, as well as the control of induced activities, to meet the requirement of manual maintenance. The beam intensities attainable in CSNS/RCS are mainly limited by beam loss induced by collective effects, e.g. space-charge forces, beam instabilities, and stripping foil scattering. A series of solutions were proposed to mitigate collective effects. After the beam loss optimization, a 100-kW beam operation with very low uncontrolled beam loss was established at the end of February 2020.
The talk will report the current status and the plan in the near future of Computing and Networking in IHEP.
Academia Sinica Grid Computing Centre (ASGC) has been developing the new generation research infrastructure for broader disciplinary scientific big data applications by distributed cloud technologies in Taiwan. The status, case studies and plans will be updated in this presentation.
Australian Physicists are participants in the Belle II and COMET experiments at KEK, the ATLAS and LHCb experiments at CERN and operate the Australian Synchroton in Melbourne. This presentation will summarise Australia's computing contributions to these activities.
Superfluid helium is another phase of liquid helium when it is cooled below 2.17 K, under saturation condition. The superfluid helium bath cools the niobium superconducting radio frequency (SRF) cavities housed in the helium tanks of the cryomodules. The SRF cavities operate at temperatures of 2.0 K or below, due to its higher operating frequency like 1.3 GHz. At KEK, the superfluid helium cryogenic plants produce superfluid helium continuously by isenthalpic expansion of the normal liquid helium (LHe) (~4.4 K) through a Joule-Thomson (JT) valve, which is connected in series with a 2K heat exchanger (2K HX). The 2K HX recovers the coldness from the 2.0 K gaseous helium (GHe) evaporating from the helium tanks of the SRF cavities. This increases the production rate of the superfluid helium by reducing the incoming LHe temperature from 4.4 K to 2.2 K or above, before the JT valve. As such, reducing the vapor flash losses from 40% to 9.4%, during the JT expansion to produce 2.0 K saturated superfluid helium. At KEK, we have a 2K HX consisting of a helical coil and laminated fins. Its performance is determined and characterized by a factor known as “effectiveness”, which is the ratio of actual heat transfer to the maximum possible heat transfer between the fluids. To produce ~2.2 K LHe at the outlet of the 2K HX and before the JT valve, the required effectiveness is > 84%. A numerical model has been developed to determine the performance parameters (effectiveness and GHe pressure drop) of the current 2K HX design and is verified experimentally using a heat exchanger test stand. Furthermore, a parametric study is conducted to improve the performance of the current 2K HX design, which was also validated experimentally. The improved 2K HXs were studied in conjunction with the GHe pumping system to determine the optimal 2K HX design that maximizes the He II production from the cryogenic systems.
Over 20 years more than 25 superconducting multipole insertion devices for generation of synchrotron radiation (wigglers and undulators) have been created at BINP for several synchrotron radiation centers. It was developed a cryogenic system based on cryocoolers which allows autonomous operation of superconducting insertion devices on the storage ring without maintenance and consumption of liquid helium for several years. The use of a cryogenic indirect cooling system allows remove vacuum chamber of helium vessel and thereby increase maximum magnetic field value due to decreasing of magnetic pole gap. For effectively cooling of indirect cooling magnet, which located in a vacuum and has no direct thermal contact with cryogenic liquids, it were used siphon-type heat pipes filled both nitrogen and helium. The design features and recent advances in the development of a magnetic and cryogenic system with liquid and indirect cooling are discussed.
The SC dipole magnet for the CBM detector consists of 150 tons mass of iron yoke, SC magnet of 5 MJ of stored energy, cryogenics adopted to the FAIR local conditions. The magnetic field in the center of the detector is ~ 1 T, on the coils is ~ 3.7 T. The superconducting cable having unique parameters was manufactured and tested. The dipole coils will be indirectly cooled by 4.5 K helium in thermosyphon regime. The magnet will be manufactured and tested in BINP. Current works are iron yoke manufacturing and coil prototype tests.
BINP presents the design and production of the 2T cryogenic solenoid for the PANDA detector at FAIR.
The report presents data on superconducting wigglers, which were made in Budker INP for various synchrotron radiation (SR) centers, their main parameters are given. Main parameters of superconducting undulator manufactured for SR DLS source are discussed. Other types of superconducting undulators based on the same key element - a superconducting magnetic element with horizontal racetrack coils - are proposed.
Since the spectral quality from cryogenic permanent magnet undulators (CPMUs) can be superior to that of in-vacuum undulators (IVUs), a PrFeB-based CPMU with a period length of 15 mm has been constructed for the Taiwan Photon Source (TPS) to provide high brilliant X-rays. Two cryo-coolers, each with a cooling capacity of 200W at 80 K, provide high temperature stability in the presence of external heat loads of up to a few hundred watts. At the lowest PM temperature of 56 K, the CPMU can generate an effective magnetic field of 1.34 T in a gap of 4 mm. An in-situ and vacuum compatible field measurement system has been developed to characterize the magnetic fields at cryogenic temperatures and allowing corrections of gap errors. The relevant technology and performance of the TPS-CPMU will be presented including observations associated with phase errors and magnetic field quality at cryogenic temperature.
A high-performance electron source is required for a stable operation of an electron accelerator and future colliders. For this purpose, the electron beam is generated in an RF photocathode-based electron gun by irradiating the photocathode with laser light. Typically, a few tens of femtosecond laser systems are routinely used to generate a pre-bunched electron beam of a few hundred femtoseconds. Recently a novel Yb-dopped fiber-based laser system with enhanced tunability and stability is being developed under KEK-IUAC collaboration to generate the electron beam for the compact THz facility of IUAC. The laser system can potentially deliver MHz-GHz-THz sequence of femtosecond pulses which populates every RF window (typically Hz rate) energizing the photocathode-based electron gun and generates a low emittance electron beam of the identical temporal structure. In this report, the present status of the laser system as well as its output parameters achieved to date will be presented. The performance characteristics and its tunability ranges will be shown and a roadmap for future developments will be discussed.
NEA (Negative Electron Affinity) activated GaAs cathode is an unique device which can generate highly spin polarized electron beam. Because the NEA activation surface has a limited robustness, it is compatible only with a DC biased gun under an extremely good vacuum condition in order of 1e-10 Pa. We propose to improve the robustness by NEA activation with a stable semiconductor thin film. We performed the NEA activation with CsKTe thin layer and the robustness was examined. The operation lifetime was improved 20 times compared to that of the conventional NEA activation with Cs and Oxygen. Assuming the lifetime, operation with a RF gun is possible for 7 hours.
The feasibility of beam injection process using a pulsed multipole kicker (PMK) magnet as a case study for the storage ring of high brilliance synchrotron radiation source (HBSRS) is investigated. For the HBSRS, the beam emittance of 150 pm rad at the beam energy of 6 GeV is considered assuming 7 bend achromatic (7MBA) type lattice configuration. The PMK magnet provides transparent top up injection, since these magnets have zero magnetic field at their center where the stored beam is passing does not receive perturbation. The injected beam is captured into the storage ring acceptance by a kick of the PMK magnet. For the beam injection studies, a single pulsed sextupole magnet (PSM) as well as non-linear kicker (NLK) magnet scheme is explored. In view of achieving more than 90 % injection efficiency, optimal strength of PSM magnet and acceptable tolerance such as injection angle errors and field strength error are estimated using tracking-based simulation code ELEGANT. The alignment errors of PSM produced unwanted kicks to the stored beam and produces the stored beam oscillation. The alignment tolerance studies for keeping the stored beam oscillation within 10 % of beam size has been studied. In this study, the beam dynamics results of multiparticle tracking simulations in low emittance storage ring are presented.
We proposed a new type of hybrid photo-detector involving photocathode, scintillator, and silicon photomultiplier (SiPM) in vacuum enclosure. Photons incident onto the photocathode are converted to photo-electrons. Then the photo-electrons are accelerated toward the scintillator by the electric field between the photocathode and electrode to produce scintillation lights. The scintillation lights are incident on the SiPM to be converted to photo-electrons, which are subsequently multiplied to 106 electrons or more by the avalanche process inside SiPM. The advantage of this type of photo-detector is that the scintillation lights contribute an extra gain in the order of tens in addition to the existing gain of 106 or higher from the SiPM. This type of photo-detector with a large area of photocathode could be used in photo-detector array for neutrino detection. We present the test result obtained with a demonstrator built to prove the principle of this type of photo-detector. We also present the design and development of the experimental setup for fabrication of this type of detector.
Taiwan Instrumentation Detector Consortium (TIDC) has been officially initiated recently. The main goal is to establish common infrastructures and resources among the Taiwan HEP community. The TIDC, formally known as Taiwan Silicon Detector Facility (TSiDF), currently serves as an important silicon module assembly center for LHC & BNL upgrade projects. The research team of TIDC consists of researchers from Academia Sinica (AS), National Cheng Kung University (NCKU), National Central University (NCU), National Tsing Hua University (NTHU), and National Taiwan University (NTU). In this presentation, we will show the facilities in each institute and the ongoing projects such as CMS-HGCAL, sPHENIX-INTT, and STAR-FST project.
SOI is a CMOS LIS technology where the MOSFETs are produced on the SiO$_2$ layer (BOX) above silicon wafers. SOI pixel sensor utilize the silicon wafer as the radiation sensor and the signal induced in the wafer is processed by the CMOS circuit on BOX. The parasitic capacitance of the circuit is smaller than that in the normal bulk CMOS, the power consumption can be suppressed than the normal (bulk) CMOS circuit. By using the SOI pixel sensor technology, we have developed pixel sensors.
In this talk, the sensors developed for the particle physics experiment will be presented.
The Circular Electron Positron Collider (CEPC) has been proposed as a Higgs Factory and aimed for high precision measurement of the Higgs boson. Collisions at lower center-of-mass energies will also allow precision measurement of electroweak observables. To fulfill the stringent requirement of precision tracking of charged particles, the tracking system must be constructed with the state-of-the-art detector technologies. Silicon sensors fabricated with High Voltage CMOS (HV-CMOS) process have become one of the most attractive device for high performance tracking. It allows integration of sensing element and readout electronics on the same silicon bulk, and provides high spatial resolution, high time resolution, fast readout and radiation tolerant. Sensors thinned down to 100 um or even lower will also reduce the material budget of the tracking system. In this talk, the HV-CMOS sensor concept will be introduced followed by test results of the prototype sensor and new development. The demonstrator and the tracking system design based on HV-CMOS will be also presented.
To meet the high precision physical goals in the future e$^+$e$^−$ circular collider (CEPC), the high resolution tracker detector for the particle track reconstruction ($\lt$100$\mu$m) and particle identification are demanded. Time Projection Chamber (TPC) is one of the main concept option of the central tracker detector. the status and update R&D results of TPC module and prototype for the specific requirements will be presented in this talk. TPC module will could suppress the ions in chamber continuously running in the different gains (2000-5000) and T2K mixture gases, and TPC prototype with MPGD detector module integrated the narrow laser calibration tracks system. This prototype has an active readout area of 200$~$mm$\times$200$~$mm and the drift length of 500$~$mm, the narrow laser beams can imitate straight ionization tracks at predefined position. 1280 channels of the electrics readout and the 20,000V of the field cage have been commissioned. Finally, the update results of the simulation and consideration will be given using the pad and pixel TPC detector concepts operating at the high luminosity $Z$ pole at CEPC.
The last few years has seen the largest underground dark matter searches rapidly approach their purported ultimate sensitivity limit, the so-called "neutrino floor". An experiment reaches the neutrino floor went it becomes so large and so sensitive that the background from coherent nuclear scattering of astrophysical neutrinos starts to drown out a potential dark matter signal. The encroachment of the neutrino floor has driven an increase in interest towards a technique which has the potential to circumvent the limit entirely: directional detection. The technique aims to measure the strongly anisotropic angular distribution of the dark matter wind incident on Earth as we journey around the Milky Way galaxy. The potential for dark matter discovery with directional detectors greatly exceeds that of conventional detectors, so the concept is well worth investigation if we 1) want to extend the search for dark matter below the neutrino floor, or 2) wish to confirm a potential signal of dark matter without relying on the controversial and systematic-prone annual modulation. While in practice directional detectors are several years away from being at a competitive scale, there several promising approaches under investigation. The CYGNUS collaboration is working towards a competitive global network of directional detectors using modular gas time projection chambers. I will give an overview of the motivation for directional detection and ongoing work trying to bring the concept to reality.
A 70 MeV commercial H- cyclotron system will be used to employ an Isotope Separation On-Line (ISOL) method for the Rare Isotope Science Project (RISP) in Korea. We made a contract with IBA in 2019 for the cyclotron system, and its installation will begin in October 2021. The cyclotron is capable of providing a beam with a current of up to 0.75 mA and has two ports for beam extraction. The beam line optics to ISOL targets was designed by IBA to fit into existing building. A wobbler magnet is used to make the beam intensity uniform with a diameter between 2 cm and 5 cm. The beam diagnostics and collimation system is critical to keep the high-current beam stable during irradiation of the ISOL target. The beam line design will be presented along with the progress in preparing for installation and the system production by IBA. In addition, the building has spare rooms to accommodate such as medical isotope production in a way to fully utilize the facility.
D-BNCT is an accelerator-based BNCT facility in Dongguan, China. The neutrons are generated from a Lithium target bombarded by a proton beam from an intense beam RFQ linac of 3.5MeV. In its initial commission stage, it can provide beam power about 10kW on a solid lithium target. The D-BNCT neutron source now is in routine operation as a BNCT test platform open for national institutes, universities or company. Based on this platform, some BNCT key technologies will be developed. Cell and animal tests have been conducted for the development of Boron drug of BPA. Another new BNCT clinic facility is under construction for pre-clinic trail in a local hospital in Dongguan.
SAMEER has proposed First Heavy Ion Therapy in India in collaboration with Tata Memorial Centre, Mumbai and KEK, Japan. The hadron driver in the proposal is based on a fast cycling induction synchrotron. Its main features are injector free, multi species of ion acceleration capability, fast cycling at 10 Hz repetition rate, energy varying 1 turn fast extraction and energy sweep extraction. These extraction mechanisms are designed specifically for treatment purpose. In the fast extraction mode, C+6 ions are extracted at any desired energy in each acceleration cycle. The extraction is assisted by an off momentum bump orbit of ions with a combination of a kicker and septum magnet. In the energy sweep extraction mode, C+5 ions are continuously leaked from the barrier bucket at desired energy and those C+5 ions drift inwards in the large dispersion region. A thin stripper foil is placed far from the center orbit of barrier trapped beam and C+5 ion hitting the foil edge gets converted into C+6 ion. The change of charge state results in large deflection in the following bending magnet and helps in extraction of the beam by a single septum magnet downstream. The charge conversion efficiency and desired stripper foil thickness have been confirmed by extensive simulations *. To realize India’s first heavy ion therapy (IndoCure), the staged plan is under consideration, where targeting fixed beam lines are expected at the first stage, with a gantry at the second stage, and then image guided irradiation on the moving target at the third stage.
Based on many years of experience in development of silicon-on-insulator (SOI) microdosimeter, the Centre for Medical Radiation Physics, University of Wollongong, has successfully developed a microdosimetric probe which is based on a SOI microdosimeter with 3D micron sized sensitive volumes (SVs) array mimicking dimensions of cells, known as the “MicroPlus-Mushroom” microdosimeters, to address the shortcomings of the tissue equivalent proportional counter (TEPC)
A method for converting silicon microdosimetric spectra to tissue for a therapeutic proton and heavier ion beams, based on Monte Carlo simulations was developed. The MicroPlus microdosimeter provides extremely high spatial resolution and were used to evaluate the relative biological effectiveness (RBE) of 12C, 14N 16O , 56Fe, 20Ne ions at Heavy Ion Medical Accelerator in Chiba (HIMAC), Japan as well as to measure the microdosimetric distributions of a proton pencil-beam scanning (PBS) and passive scattering system at different proton therapy centres. Good agreement between predicted cell survival response using MKM and measured from in vitro experiments in the same radiation field allow replacing time consuming cell experiments with MicroPlus microdosimeter measurements.
Another application of SOI microdosimeter is for evaluation of radiation shielding and radiation protection of astronauts in radiation environment typical for SPE and GCR. We demonstrated that SOI microdosimeters are suitable for in situ evaluation of radiation shielding efficiency of multi-layered space craft and astronaut shelter walls in radiation fields on accelerators mimicking SPE and GCR. SOI microdosimeters supplement Monte Carlo simulation which not always accurate due to lack of knowledge of cross sections and time consuming.
Silicon detectors for fast verification of range, energy and spot position of proton and carbon ion pencil beam scanning for daily QA will be presented.
Plasma wakefield accelerators, driven by either short laser pulses or charged particle beams, have the acceleration gradient of the order of 1 to 100 GeV and are regarded as the accelerators of the next generation. In this talk, I will introduce the plasma wakefield accelerator studies at Institute of High Energy Physics, Chinese Academy of Sciences, including the CEPC plasma injector studies, the studies of controlled injection methods, and the study of radiation reactions in a plasma wakefield accelerator.
The concept of Circular Electron Positron Collider (CEPC) was presented in 2012
aiming to further study the Higgs bosons. It mainly consists of three parts including a linac, a booster and a collider. That CEPC booster needs to boost the beam energy from 10 GeV to 45.5 GeV brings many difficulties to fabricate and measure the dipole magnet. One of the practical way to avoid the low ?field dipole issue of the booster is to introduce the CEPC Plasma Injector (CPI) to boost the beam energy before injecting the beam into the booster.
In this work, we present preliminary studies on CPI, including simulation studies on electron acceleration with high transformer ratio and new schemes for positron acceleration. In addition, we also present some experimental results on plasma dechirper at THU lab.
Laser Wakefield Acceleration (LWFA) of charge particles (for example: electron beam) has potential to drastically reduce the size of the future particle accelerators. Owing to its compact size, even for GeV class acceleration of particles, LWFA has ability to serve the broad user communities of the next generation of radiation sources based on free-electron-laser (FEL) [1]. *MIRAI project is one of the highly ambitious projects in this category among similar research work at other laboratories in the world. MIRAI project is aiming for multi-stage acceleration of electron beams in LWFA configuration, employing energy slicing and chirp rotation schemes, in order to deliver GeV class electron beams with energy spread below 1%. Later, these electron beams will be synchronized with the micro or conventional undulators for radiation generation.
In this presentation we will show the design concept and present status of the MIRAI project. We will also show the recent progress made in successful demonstration of multi-staging of LWFA with an energy gain close to 100 MeV in the booster stage (second stage) and their preliminary coupling with the undulator.
*https://www.jst.go.jp/mirai/en/program/large-scale-type/theme01.html
[1] H. P. Schlenvoigt et. al., Nat. Phys. 4, 130 (2008).
Acknowledgements
This research is funded by JST-MIRAI Program Grant No. JPMJMI17A1 and was partially supported by ImPACT R&D Program of council for science, technology and innovation (Cabinet Office, Government of Japan). We acknowledge the use of Mini-K computing facility at SACLA, SPring-8.
Electron acceleration driven by laser wakefield using a laser pulse with circular polarization is studied with the objective to generate high-quality electron bunches with narrow energy spread and small emittance. In order to inject electrons into the accelerating phase of the plasma wave, a density transition shaped as bump is employed. Using particle-in-cell simulations, we demonstrate the influence of laser polarization on the quality of electron bunches. Simulation results, using experimentally achievable parameters, show that electron bunches with an energy spread of $ \sim 2.6\ \%$ are obtained for the circular polarization as compared to $ \sim 9.3\ \%$ energy spread for the linear polarization in a mm-scale length plasma. The results show an improved quality electron bunch generation from laser wakefield acceleration. The predicted electron bunch quality may be crucial in developing plasma based electromagnetic radiation sources.
Electron–photon scattering, or Thomson/Compton scattering, is one of the most fundamental mechanisms in electrodynamics, underlying laboratory and astrophysical sources of high-energy X-rays. After a century of studies, it is only recently that sufficiently high electromagnetic field strengths have been available to experimentally study the nonlinear regime of the scattering in the laboratory. This can act as a new generation of accelerator-based hard X/γ-ray sources driven exclusively by laser light. One ultrahigh intense CPA laser pulses will act as two means: first used to accelerate electrons by laser driven wake field (LWFA) to hundreds MeV, and second, from split beam or LWFA-leftover energy reflected by plasma mirror, to collide on the electron for the generation of X/γ-rays. Such all-laser-driven X/γ source have recently been demonstrated to be energetic, tunable, narrow/broad in bandwidth, short pulsed and well collimated. Such characteristics, especially from a compact source, are highly advantageous for numerous advanced X-ray applications. Moreover, the scattering interaction can act a test bed for high-field QED study. Also, preliminary plan of laser wake-field accelerator and radiation source in high-power laser facility in SJTU and TDLI will be presented.
Direct laser acceleration (DLA) of electron with intense high order modes of Laguerre Gaussian (LG) laser beam is investigated theoretically. The electron laser interaction is found to be sensitive with the radial (p) and azimuthal (m) mode indices for a polarized LG laser beam. Depending upon the order of mode indices (p,m), it is possible to derive the electron dynamics and energy gain with the variations of electric and magnetic fields characteristics of LG laser beam. The optimal values of beam parameters which leads to the most energetic electrons, is investigated and presented for the increasing power of LG mode indexed laser beam. The study opens new insights on mode indexed LG laser beam based applications with charged particle interactions.
A plasma source is a vital part in laser wakefield acceleration (LWFA) and a gas cell is one of the main sources for that purpose. In our laboratory, we have developed diverse capillary plasma sources for LWFA in recent years. In this talk, development and characterization of a special gas cell with a longitudinal density tapering are presented, in which a higher electron acceleration energy is expected.
An RF driven negative hydrogen source is under development for the upgrade of China Spallation Neutron Source (CSNS), which requires an H$^-$ beam current more than 50 mA, and a duty factor of 1.5%$\sim$2%. The ion source produces an H$^-$ beam of 20 mA without cesium injection. After it is cesiated, about 47 mA H$^-$ beam is extracted. The emittance of the ion beam is measured both with a double-slit scanner and a pepper-pot device. It gives a normalized root of mean square emittance of more than 0.4 $\pi\cdot$mm$\cdot$mrad at a beam current of 27.5 mA, which is much lager than the acceptance of Radio-frequency Quadruple (RFQ) accelerator located downstream. To find the reason, the magnet field distribution of the extraction system is measured. Based on the measurement, the trajectories of the H$^-$ beam and the co-extracted electron beam are simulated with CST program.
Permanent magnet multipoles can be used for efficient hadron beam transportation. In this presentation, combined quadrupole and octupole magnets for intense ion beam focusing and sextupole magnets for neutron beam focusing and will be presented.
Variable Energy Cyclotron Centre (VECC) is a R&D unit of the Department of Atomic Energy, Government of India. This Centre is dedicated to carry out frontier research and development in the fields of Accelerator Science & Technology, Nuclear Science (Theoretical and Experimental), Material Science, Computer Science & Technology and in other relevant areas.
VECC has been delivering proton, alpha and heavy ion beams from K130 room temperature cyclotron for users. Recently beam has been extracted successfully from a K500 superconducting cyclotron for the first time. A 30 MeV medical cyclotron has been commissioned and started routine production and delivery of PET isotopes for patients to different hospitals. An ISOL post-accelerator type of RIB facility has been developed with the K130 cyclotron as the primary accelerator. Status of these accelerators and related interesting developments will be presented in this talk.
An accelerator based neutron source is in operating at the BINP for the development of Boron Neutron Capture Therapy and other applications. Phase space of proton beam was measured using a cooled diaphragm and a wire scanner. The measured phase space and the calculated invariant normalized emittances make it possible to conclude that the proton beam can be transported to an adjacent experimental bunker for clinical trial of Boron Neutron Capture Therapy and down to a protected room for radiation testing of materials developed for ITER and CERN.
The reported study was funded by the Russian Foundation for Basic Research, project no. 19-32-90118.
The Tokyo Tier-2 site, which is located in the International Center Elementary Particle Physics at the University of Tokyo, provides computing resources for the ATLAS experiment in the Worldwide LHC Computing Grid. Status of the site and recent R&D activities, such as an integration of HPC resources to the site, will be reported.
Various types of experiments in the field of accelerator-based science are actively running at the High Energy Accelerator Research Organization (KEK) by using SuperKEKB and J-PARC accelerator in Japan. The computing demand from the recent experiments for the data processing, analysis, and MC simulation is monotonically increasing. According to the computing demand, KEK Central Computing System (KEKCC) has been upgraded every four or five years. The currently running system was just renewed in September 2020. In this talk, we would like to introduce the scale-up of the computing resource and improvement of services including the Grid system of the new KEKCC.
The presentation indicates the status of the Super-Charm-Tau factory detector project software development and describes the Budker INP computing facilities providing the required resources.
High Energy Photon Source (HEPS) is the first high-energy ring-based synchrotron radiation light source in China. The HEPS is designed with a beam energy of 6GeV and an ultra-low emittance of better than 0.06nm.rad to provide high-energy, high brightness hard X-rays. In phase I for the HEPS 15 public beamlines and corresponding experimental stations will be constructed by Institute of High Energy Physics in Beijing. The main HEPS cryogenic users are superconducting frequency (SRF) cavities with 80K thermal shields, cryogenic permanent magnets, cryogenic cooling monochromator and experimental stations. Cooling power of 2.0kW@4.5K is required to maintain operation of the superconducting system and called helium cryogenic plant which will operates in two modes. The modes include 300-150K gradual cooling down at 10K/h and 150-4.5K fast cooling down in 1 hour. And an average capacity 50kW at 80K nitrogen cryogenic plant is also desiged in the HEPS cryogenic system. The nitrogen cryogenic plant is designed with two parts. One is nitrogen refrigerating cycle system for SRF cavity cryomodules and another is a liquid nitrogen suppling and distributing system along the 1360m long storage ring for beamlines. In this paper, the process of the cryogenics of HEPS is presented.
SHINE, the Shanghai HIgh repetitioN rate XFEL and Extreme light facility, a quasi-continuous wave hard X-ray free electron laser facility, is currently under construction. The SHINE cryogenic system is divided into three groups, the test facility cryogenic system, the accelerator cryogenic system and undulator cryogenic system. Among the three cryogenic system, the test facility cryogenic system is the first system to be designed, procured, installed and commissioned. It is designed to provide 1kW cooling power at 2K with mixed cycle using both cold compressor and warm process pumps. Up to now, the warm compressor system, cold box system integrated with cold compressor, process pumps system, and the distribution system have already been installed and are now under commissioning. Meanwhile, the accelerator cryoplant with a capacity of 12kW@2K in total has been procured and is now in the design phase. In this paper, the design specification, process analysis, system scope, conceptual layout, description of single compotes, and preliminary schedule of the cryogenic system for the SHINE test facility and accelerator system will be introduced.
Platform of Advanced Photon Source Technology R&D (PAPS) was officially launched in Beijing Huairou Science City in Feb. 2017. The goal of the PAPS project is to provide a good foundation and condition for R&D, engineering testing and verification for the high energy phone source (HEPS), especially the R&D of different SRF cavities for the future scientific project. The cryogenic test facility with totally 2.5kW@4.5K cooling capacity and separately 100W@2K cooling capacity for the 3 test station to meet the requirements of the SRF cavities’ vertical, horizontal and beam test. The whole project will be finished in the middle of this year.
Vertical Test Stand (VTS) and Horizontal Test Stand (HTS) Facilities are set-up at RRCAT for testing and qualification of Superconducting Radio Frequency (SCRF) Cavities. VTS facility is operational since 2013 and tested many single cell and multi-cell 1.3 GHz and 650 MHz cavities at 2 Kelvin. HTS is in its commissioning trials. HTS cryostat designed for cooling down two 650 MHz dressed SCRF cavities with RF powering of one cavity at a time. Operation of VTS needs to handle around 5000 liters of liquid helium and HTS operation requires to produce 4.5 K helium in super-critical state in order to achieve 2 K in these facilities. Large scale cryogenic facilities are set-up and being upgraded to operate these facilities successfully. Present talk summarizes the cryogenic requirement and facilities created for successful operation of SCRF cavity test stands.
We are developing relatively large 2D 4-mirror optical cavity to reduce the crossing angle between electron bunch train and laser pulse train. Total length of first 2D 4-mirror optical cavity is 7.56m and it includes 9 laser pulse train to realize the crossing angle of 8 degrees between electron beam in Linear accelerator and the laser pulse train in the optical cavity [1]. Second 2D 4-mirror optical cavity is under design and the total length of planed cavity is 16.6m in which 18 laser pulse train can circulate and we have the possibility to realize the crossing angle of 2 degrees.
I will report the performance of first 2D 4-mirror optical cavity and the experimental plan on 2D 4-mirror optical cavities. Below photo shows 1.9m long 2D 4-mirror optical cavity which is operating to generate X-ray. We hope it will be installed into Super-conducting Linear accelerator (STF) to generate high brightness gamma-ray in the future.
Kazuyuki Sakaue, Masakazu Washio, Sakae Araki, Masafumi Fukuda, Yosuke Honda, Nobuhiro Terunuma, and Junji Urakawa, “Stabilization of an optical enhancement cavity using a counter propagating mode” REVIEW OF SCIENTIFIC INSTRUMENTS 89, 023305 (2018).
The compact THz-FEL facility, based on the RF photocathode electron gun, is under the commissioning stage at Inter University Accelerator Centre (IUAC), New Delhi. Once operational, it will be the first pre-bunched FEL facility in India and will be among the few in the world [1,2]. The complete accelerator facility will be ~ 5 meters long and will deliver intense THz radiation as well as an electron beam for doing experiments in the multidisciplinary fields. The electron gun, powered by a Klystron/Modulator, is expected to generate an accelerating field of ~ 120 MV/m (max.) which will produce an electron beam of energy of ~ 8 MeV. The electron beam, after being focused by solenoid and quadrupole magnet, will be injected into a compact undulator to produce THz radiation in the frequency range of 0.18 to 3.0 THz.
The various subsystems of the THz facility are either commissioned or in their final stage of installation. The cavity, the waveguides and the Klystron/Modulator have been commissioned and the RF conditioning of the electron gun is presently on. The beam line is installed up to the entrance of the Undulator with the majority of the equipment already installed and aligned. The undulator has arrived at IUAC from Deutsches Elektronen-Synchrotron (DESY), Germany and will be commissioned in the beam line shortly. The photocathode deposition chamber and the fiber laser system are in the final stage of testing at Brookhaven National Laboratory, USA and at High Energy Accelerator Research Organization (KEK), Japan, respectively. They are expected to arrive at IUAC in the next few months. The electromagnets (dipole, quadrupole and steering) were developed, characterized at Bhaba Atomic Research Centre and were received at IUAC.
After the installation of the fiber laser system at IUAC, the cavity will be conditioned with the Copper photocathode plug and the electron beam will be produced from the electron gun. The THz radiation will be demonstrated subsequently, by injecting the same electron beam into the compact undulator. It is likely that both the events will take place by the end of 2021.
The status of the commissioning of the facility and the testing of the various subsystems of the accelerator will be presented in the AFAD workshop.
References
1. S. Ghosh et al. Nuclear Instruments and Methods in Physics Research – B 402, (2017) p. 358-363.
2. V. Joshi, et al., Nuclear Instruments and Methods in Physics Research – A 913, (2019), page 28-39.
The High Energy Photon Source (HEPS) is a 34-pm, 1360-m storage ring light source being built in the suburb of Beijing, China. The construction of the HEPS started in mid-2019.In this report we will introduce the construction status of the HEPS, and especially discuss the progress of the physics design and studies on the accelerator.
A hard X-ray engineering application beamline (BL-02) was commissioned recently and started operation in March 2019 at Indian synchrotron storage ring Indus-2. This beamline is capable to operate in various beam modes viz; white beam, pink beam and monochromatic beam. The beamline utilizes X-ray diffraction technique in energy dispersive and angle dispersive modes to carry out experiments mainly focused on engineering problems viz; stress measurement, texture measurement and determination of elastic constants in variety of bulk as well as thin film samples. An open cradle six circle diffractometer with ~12 kg load capacity allows accommodation of wide variety of engineering samples and qualifies the beamline as a unique facility at Indus-2. The high resolution mode of this beamline is suitably designed so as to carry out line profile analysis (LPA) for characterization of micro and nano-structures. In this presentation beamline design, various operational modes and experimental stations are described. Commissioning issues related to experiments executed to validate the beamline design parameters and to demonstrate the capabilities of beamline are discussed in this lecture.
Indus-1 and Indus-2 are electron storage ring based synchrotron radiation sources at RRCAT. Lately few upgrades and additions have been carried out for some of the pulse sources in Indus-2. In this talk, these upgrades / additions to pulse sources in Indus-2 will be discussed. Pulse sources to energise Indus-2 Injection kicker magnets are working in the machine for last 15 years. These pulse sources are working in the machine in severe space constraints with large pulse power assemblies in oil tanks and any maintenance or on site measurements is very cumbersome for the working personnel attending it. So it was planned to design and develop new pulse source with an upgraded design. Efforts were made to reduce the working voltages in the new design and thereby remove the oil assemblies. Pulse source has been designed and developed to deliver 6 kA of peak current with a half sine pulse width of 3usec. in Indus-2 kicker magnet as load. Repetition rate of pulse is 1 pulse per second. Developed pulse source has been tested with Indus-2 kicker magnet in lab.
Also it was decided to equip Indus-2 with two pinger kicker systems. Pinger kicker system will consist of two types of kickers namely horizontal and vertical pinger kicker. These pinger (kicker) magnets are energized by two separate pulse sources. These kickers will generate betatron oscillation in the stored beam (few bunches) of Indus-2 in a synchronised operation. The kickers will act as a tool to probe the linear and non linear dynamics of the beam. The turn by turn oscillations of the beam are captured by beam position monitors of the ring. Two pulse sources to energise these kicker magnets respectively has been developed. Vertical pinger kicker system has already been installed in the ring. Horizontal pinger pulse source development has also been completed and the same has been tested with kicker magnet in lab. Installation and commissioning of horizontal kicker system in Indus-2 ring is also planned shortly. Technical requirement of these pulse sources, their development and test results will also be discussed in this talk.
The detector developments for fast and super-fast time-resolved studies at SR beams will be reviewed. Two detectors based on Si micro-strip technology are developed at present in Budker INP SB RAS. The detector for imaging of super-fast processes at a nanosecond scale, DIMEX-Si allows to improve by more than a factor of ten maximum detected photon flux, with respect to the gaseous version of such detector, that is operating at VEPP-3 for more than 15 years; the frame rate is increased from 10 MFr/s up to 50 MFr/s and spatial resolution is improved from 250 um to about 70 microns. The new full-size detector prototype for the studies of tungsten deformations under pulse heat load in a microsecond scale is recently developed. It has significantly better spatial resolution and sensitivity compared to the gaseous DIMEX detector that was used for these studies before.
The High Energy Photon Source (HEPS), which will be the first high-energy synchrotron radiation light source in China, is currently being built in Beijing. The hard X-ray with photon energy up to 300 keV will be provided and no less than 90 high performance beamlines and end-stations will be built around the storage ring. However, even the state-of-the-art detectors cannot satisfy the requirement of various experiments.
BPIX is a hybrid pixel detector that was designed dedicatedly for the beamlines of HEPS. It works in single photon counting mode for X-ray applications. With 1.4M pixel cells sized 150μm×150μm, the full detector can operate with a frame rate as high as 1.2kHz. This paper will introduce the system design, including the newly developed detector that utilizes the TSV (Through Silicon Via) technology for fine module assembly gaps. Several new detector prototypes with new concepts will also be introduced.
The electron-positron collider VEPP-2000 is operating now at Budker Institute of Nuclear Physics. Two detectors CMD-3 and SND are installed in the interaction
regions of the collider. From 2010 until now the total collected luminosity integral is about 2 X 300 pb−1. CMD-3 is a general purpose detector designed to study e+e− annihilation into hadrons in the whole energy range of the collider - Ec.m.s = 0.3 ÷ 2 GeV. The barrel calorimetry subsystem of the CMD3 detector is represented by combined LXe/Crystal calorimeter. The design of the calorimeter, the methodic of calibration, its current possibility of particle identification and also positive and negative experience of calorimeter operating are presented.
Taiwan Applied Crystal Co., LTD develops a series process to produce high light yield and fast timing scintillator. Patented recipes from NSYSU and
unique crystal growth to meet those requirements.
The Compact Muon Solenoid (CMS) detector at the European Council for Nuclear Research (CERN) Large Hadron Collider (LHC) is undergoing an extensive Phase II upgrade program to prepare for the challenging conditions of the high-luminosity LHC (HL-LHC). In particular, a new timing layer will measure minimum ionizing particles (MIPs) with a time resolution of ∼30–40 ps and hermetic coverage up to a pseudorapidity of |η| = 3. The precision time information from this detector will reduce the effects of the high levels of pileup expected at the HL-LHC and will bring new and unique capabilities to the CMS detector. This MIP Timing Detector (MTD) will consist of a central barrel timing layer (BTL) based on L(Y)SO:Ce crystals read out with silicon photomultipliers (SiPMs) and two end-caps layer (ETL) instrumented with radiation-tolerant low-gain avalanche detectors (LGADs). We present the current status and ongoing R&D of the ETL, including recent test beam results in this talk.
The dual-readout method is a state of the art calorimetry technique enables high-quality energy measurement for both electromagnetic and hadronic particles, which has been developed during last two decades. The dual-readout calorimeter detector mainly designed by Korean team has been included in the conceptual design reports of both FCC-ee and CEPC projects published in 2018. As a next step, Korean team has a plan to build a prototype detector and demonstrate all necessary requirements of the detector toward TDRs of the FCC-ee and CEPC projects. Recent progress and plan of the dual-readout calorimeter R&D in Korea will be presented in this talk.
Geant4 is a simulation toolkit for radiophysics related to HEP experiments. International collaboration among KEK, CERN, and the other research institutes associated with HEP experiments have developed Geant4 for more than 20 years. Currently, Geant4 has widely been used in various research fields other than HEP experiments. Geant4-Japan group has been focusing on Geant4 application studies for medicine and radiobiology for over a decade. In this presentation, I will share our current activities.
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Both 3D quasi-static PIC code and the quasi-3D PIC code using azimuthal decomposition method can obtain 100-1000 times speedup than the normal PIC code when modeling the plasma wake field accelerator. However, when pursuing higher energy and finer physics in the PWFA problems, a code that can cost less computing resources is required. Therefore, we apply the azimuthal decomposition method in the quasi-static PIC algorithm and develop a new code. The code is based on the open source 3D quasi-static PIC code QuickPIC, and it is called QPAD that stands for QuickPic with Azimuthal Decompostion. In this work, we present the basic algorithm in QPAD and some comparisons between QPAD, QuickPIC and a fully 3D PIC code OSIRIS.
We review the activity of four research groups:
- theoretical group that develops a quasi-static code LCODE for simulations of plasma wakefield acceleration and makes numerical and theoretical studies of plasma based accelerators;
- theoretical group that studies collective relaxation of electron beams and THz radiation from plasmas;
- group that develops novel W-band accelerating structures;
- experimental group that prepares laser-plasma experiments with a two channel multiterawatt laser system based on OPCPA.
Studies of plasma-based acceleration techniques rely heavily on numerical simulations. The development of computationally simple models is an important part of researches. Quasistatic approximation is the fastest one but it does not take into account the self-trapping of plasma electrons in bubble regimes. The fraction of such particles is small compared to all plasma electrons. We calculate fast plasma electrons with full equations of motion when their Lorentz gamma factor exceeds trapping threshold. We implement this algorithm in code LCODE and optimize the interaction of 300 mJ laser pulse with plasma to obtain accelerated electron beam after gas jet target. Simulations of FBPic code that does not include the quasistatic approximation shows similar results.
We will present the recent results which include: relativistic self-trapping regime of laser pulse propagation in the near critical density plasma, betatron wakefield radiation of record brightness and hardness, effective laser production of gammas, positrons, and photonuclear particles from optimized electron acceleration in low-density targets, shielded radiography with gamma rays from laser-accelerated electrons in a self-trapping regime, ultrafast target charging due to polarization triggered by laser-accelerated electrons, short laser pulse heating of microstructured targets and clusters, radiation source from THz to soft x-ray range based on the laser accelerated recirculating electrons at thin foils, and new methods of extreme light diagnostics. These studies have been performed with support of the State Assignment for Lebedev Physics Institute, Russian Science Foundation (Grant No. 17-12-01283), Russian Foundation for Basic Research (Grant No. 18-02-00452), and Foundation for Basic Research and ROSATOM (Grant No. 20-21-00023).
Institute of Applied Physics of the Russian Academy of Sciences (IAP RAS) is the leading Russian center on high power laser-plasma interaction. It includes 0.5 PW OPCPA laser facility PEARL. The report will provide an overview of the most significant areas of research carried out at the facility, which includes research in the field of laboratory astrophysics, particle acceleration, and photon generation in hard-to-reach parts of the electromagnetic spectrum.
Based on the research experience of CLAPA [1,2] (Compact Laser Plasma Accelerator), a new laser accelerator used for proton therapy facility named CLAPA-II [3] is proposed and under design by PKU. This facility will for the first time adopt the near critical density target, consisted of the self-sustained foil material and the carbon nanotube, as the key technology in laser-driven ion accelerators. The laser accelerator is able to repeatedly generate proton beams with high peak flux and short temporal duration in the energy level of multi hundreds MeV. The resulting beam can meet most of the therapeutic needs.
It is always an important step that how to design a beam transport line suitable for the beam accelerated by CLAPA-II. Through the design and construction of the transmission line for the laser-accelerated ion beam, the beam with 100 MeV and 0~±5% energy spread can be accurately transmitted. Science design process, the achromat lattice is designed for control the envelope growth caused by dispersion and large energy spread. Superconducting solenoids and magnets with mixed magnetic field are used to make the beam line more compact.
High energy ion acceleration beyond 10 MeV is driven by high intensity lasers in the Target Normal Sheath Acceleration (TNSA) regime.
However, contaminants on a solid target surface degrade the performance of heavy ion acceleration.
We proposed the tape target with heating to supply contamination-free targets with long term operation.
In this presentation, laser-driven ion acceleration using a 5 µm Ti with CW laser heating was demonstrated for oxygen ion source.
A Thomson parabola spectrometer provided evidence that oxygen ions were preferentially accelerated compared to the case without the heating.
The results indicate stable thin oxide layers on the surface of the Titanium foil can be accelerated when we apply the heating.
In the Budker Institute of Nuclear Physics an accelerator based epithermal neutron source was proposed and designed [1] to the development of the perspective cancer treatment, which is the Boron Neutron Capture Therapy. The principal unit of the facility is the neutron producing target. The target was irradiated by the proton beam with various energy values from dozens of keV to 2 MeV. Moreover, the current of the proton beam was gradually changed from dozens of µm to 2.5 mA. With the proton beam hitting the target surface the luminescence was detected. The luminescence was visually seen with the use of Smart IP-camera (Hikvision, China), mounted on the BaF2 window. The observed wavelengths were measured using spectrometers (HR2000+ (Ocean Optics, UK), CCS100 Compact Spectrometer (Thorlabs, USA)). The spectrum measurement was carried out through the window with the fused quartz glass. The distinctly distinguished spectral lines of lithium (670.67 nm and 610.4 nm) were detected. Furthermore, hydrogen lines were detected, which correspond to the proton beam presence, and lines suspected to be caused by an argon presence.
It is very important to be sure that the proton beam is on the target during the experiments. The luminescence allows online watching for the proton beam footprint on the target in the process of neutron generation. In this way, it helps to control the location of the proton beam.
Acknowledgments
The reported study was funded by RFBR, project number 19-32-90119.
References
1. S.Yu. Taskaev. Accelerator Based Epithermal Neutron Source. Physics of Particles and Nuclei, vol. 46, No. 6, page 956–990 (2015).
A high-intensity proton accelerator facility requires a high current pulsed negative hydrogen ion source. A Cs-free, negative hydrogen ion source has been developed using inductively coupled discharge technique in pulsed mode by 2 MHz RF external antenna. The RF power coupling to the plasma is enhanced by introducing C-shaped ferrite core around the RF antenna. No external multi-cusp magnetic field is used for plasma confinement, since the magnetic field generated by RF antenna current itself confines the plasma. For high duty factor operation efficient water cooling arrangement is implemented for plasma chamber, RF antenna, ferrite core, plasma electrode, ignitor etc. The presentation will cover, full power testing of solid state RF source, RF antenna and ferrites, cooling arrangement of plasma chamber and biased faraday cup, remote control operation and beam spot measurements. This source is operated at 10 Hz repetition rate, 2 ms pulse duration and 50 keV beam energy and extracted negative hydrogen ion beam current of 20 mA. The key experimental results will be reported in the presentation.
To achieve high intensity, high power or high luminosity, next-generation hadron accelerators like HIAF (High Intensity heavy ion Facility) and EicC (Electron ion collider in China) employ a lot of entirely new beam dynamics and new technology. The development of a simulation code CISP (Simulation Platform for Collective Instabilities) and a control system PACS (Physics-oriented Accelerator Control System) is underway in IMP (Institute of Modern Physics), China, which aims at building an advanced accelerator software platform for the design and operation of these facilities. CISP is a scalable multi-macroparticle simulation code that can simulate basic beam dynamics, acceleration, barrier bucket bunch merging, space charge effects, collective instabilities, feedback systems, etc. and their combining effects in a single simulation. After performing benchmarks with theory results and results of other simulation codes, CISP has been applied to research special beam dynamics in HIAF-BRing successfully. PACS is an advanced accelerator high-level control system which concentrates on transforming beam dynamics studies into online control models perfectly and quickly. After about 10-month development, a version of PACS has been deployed to HIRFL (Heavy Ion Research Facility in Lanzhou). The first beam commissioning with PACS in August 2020 was quite successful. PACS is in operation in HIRFL now and will be deployed to SESRI (Space Environment Simulation and Research Infrastructure) which is also a national facility in China. In the future, CISP and PACS will be integrated into a unified software platform that can significantly improve the design and operation in the next-generation research and application accelerator facilities.
KREONET (Korea Research Environment Open Network), National Science and Research Network, has provided high performance networking for data-intensive science and multi-disciplinary research in Korea. Practically, the infrastructure and service of KREONET/KREONet2 and several activities for the HEP community such as LHCOPN/LHCONE will be introduced in this talk.
High-energy physics (HEP) has traditionally been studied with experimental, theoretical, and computational simulations combined with e-Science so that it can be studied anytime and anyplace. The recent production of big data needs high-speed data processing and artificial intelligence. As artificial intelligence evolves into machine learning and deep learning, high-energy physics requires a huge amount of evolving computing. Let me introduce the evolving computing architecture for HEP researches in Korea.
3W1 SC wiggler with the pole gap of 68 mm have been successfully tested and installed in the BEPC II storage ring in November 2019. The goal of zero liquid helium consumption is achieved, and the residual cooling capacity of cryogenic system is about 0.69 Watt @4.2 K, equivalent to 12% of total cooling capacity of cryogenic system. The 2.6 Tesla magnetic field has been achieved and 3W1-SCW will be operating at 2.49 Tesla, which is acceptable for beam load work, and now experiments are carried out. 3W1-SCW has been operated for more than 6 month and the cryogenic system has been subjected to the impact of magnet quench for three times. The automatic pressure relief valve is opened immediately to discharge the pressure of the helium vessel when the pressure of the helium vessel is higher than set point, and the released helium gas will be automatically stored in helium gas bag.
SHINE project is under the key technology R&D, the main facility engineering design, and the building construction period. Some prototypes, including e-gun, superconducting RF cavity, superconducting undulator, as well as beam diagnostic devices are manufactured. For the superconducting RF cryomodule, the key components prototype fabrication, the cryomodule integration and test, as well as the infrastructure construction are carried out in parallel. This talk will give a general introduction on the construction status of SHINE and the progress of cryomodule R&D.
After the construction, PAL-XFEL was open to the public in 2017 as the third Hard X-ray FEL machine on the globe and it has been operated successfully for the user service up to now. In this talk, the operation status of PAL-XFEL will be presented including the recent progress for better performance.
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