Contribution Oral presentation
Study of focusing aerogels with electron beam
Recent results from the beam test of the FARICH detector prototypes at the BINP electron beam line are reported. We studied several samples of focusing aerogel using multichannel SiPM photodetectors with a high position resolution. One of photodetectors was based on novel digital SiPM technology - Digital Photon Counter produced by Philips. Particle track was measured by gaseous strip detectors based on GEMs that have 70 μm resolution. That allowed us to precisely measure the radius distribution of Cherenkov photons from aerogel and compare with a prediction based on aerogel refractive index profile obtained by a digital radiography. In 2012, the first aerogel blocks with a continuous density gradient along thickness were produced. This technology can dramatically reduce the contribution from the radiator thickness to the resolution of the measured Cherenkov angle in the FARICH detector. A special automatic setup was used to control reagents ratio during the synthesis process. The first few samples were tested using a digital radiography and the electron beam.