Measurement of optical parameters of aerogel Buzykaev, A.R.; Danilyuk, A.F.; Ganzhur, S.F. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/1999, Volume:
433, Issue:
1
Journal Article
Peer reviewed
The work is devoted to the measurement of optical parameters of aerogel which can be used as Cherenkov light radiator. The refractive index, the light scattering and absorption lengths, the variation ...of the refractive index inside an aerogel block were measured for the aerogel produced conjointly by the Institute of Catalysis and Institute of Nuclear Physics (Novosibirsk). Atomic and nuclear properties of the aerogel are presented.
Aerogels with high optical parameters for Cherenkov counters Buzykaev, A; Danilyuk, A; Ganzhur, S ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/1996, Volume:
379, Issue:
3
Journal Article
Peer reviewed
Using a two-stage sol-gel method and high temperature supercritical solvent removal, blocks of SiO
2 with a refractive index
n = 1.01−1.05 have been prepared. Measurements show that these aerogels ...have high values of scattering and absorption lengths.
Aerogel Cherenkov counters for the KEDR detector Barnyakov, M.Yu; Bobrovnikov, V.S; Buzykaev, A.R ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2000, Volume:
453, Issue:
1
Journal Article
Peer reviewed
The project of Cherenkov counters based on Aerogel, wavelength SHIfter, and PHotomultiplier (ASHIPH) for the KEDR detector is described. The Monte Carlo simulation of number of photoelectrons was ...carried out. The first counters have been produced. Measurements with cosmic particles were performed. As compared with the direct light collection on PMT, the ASHIPH method allows the diminishment of the number of PMTs essentially. The optical properties of aerogels produced at KEK and at Novosibirsk are presented.
Observation of Upsilon(4S) decays to pi(+)pi(-)C and pi(+)pi(-)Upsilon(2S)We present the first measurement of Upsilon(4S) decays to pi(+)pi(-)Upsilon(1S) based on a sample of 230 x 106(4S) mesons ...collected with the BABAR detector. We measure the product branching fractions Beta(Upsilon(4S) --> pi(+)pi(-)Upsilon(1S)) x BetaUpsilon(1S) --> mu(+)mu(-) = (2.23 +/- 0.25(stat) +/- 0.27(syst))x 10(-6) and Beta(Upsilon(4S) --> pi(+)pi(-)Upsilon(2S) x Beta(Upsilon(2S) --> mu(+)mu(-))=(1.69 +/-0.26(stat) +/- 0.20(syst)) x 10(-)6, from which we derive the partial widths Gamma(Upsilon(4S) --> pi(+)pi(-)Upsilon(1S))=(1.8 +/-0.4) keV and Gamma(Upsilon(4S) --> pi(+)pi(-)Upsilon(2S))=(2.7 +/- 0.8) keV.
The paper deals with the development of Cherenkov counters based on Aerogel, wavelength SHIfters and PHototubes (ASHIPH). Microchannel plate photomultipliers with multialkali photocathodes are used. ...Data on the PMT multiplication gain in the magnetic field and noise are presented. The main parameters of the wavelength shifters, aerogel SAN-96, and the PTFE reflector are measured. The project of the ASHIPH system is developed for the KEDR detector. The counters will operate in a 1.8T magnetic field and will separate π- and K-mesons in the momentum region of 0.6 – 1.5GeV/c. Compared to the option of the direct light collection on the photomultiplier, this method offers a possibility to diminish the number of PMTs essentially. The possibility to increase light collection in the ASHIPH detector using a combination of ‘blue’ and ‘green’ shifters is discussed.
Project of aerogel Cherenkov counters for KEDR Buzykaev, A; Cherepanov, C; Danilyuk, A ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/1996, Volume:
379, Issue:
3
Journal Article
Peer reviewed
An aerogel Cherenkov counter system for the KEDR detector is developed. Light collection on photomultipliers by WaveLength Shifters (WLS) is used. The shifter KN-18 was developed. The reflection ...coefficients of light in PTFE teflon and Millipore paper were measured. A prototype of the counter was tested using a relativistic particle beam at CERN. The experimental and Monte Carlo simulation results are in good agreement.
Four-layer aerogel Cherenkov counter Arisaka, K.; Borsato, E.; Boutigny, D. ...
Journal of non-crystalline solids,
1998, Volume:
225
Journal Article
Peer reviewed
Open access
A 4-layer design of aerogel threshold counters using two refractive indices was suggested for the particle identification in the forward region of the BaBar detector. Three prototypes filled with the ...high quality aerogel produced in Novosibirsk were tested at T10 beam at CERN. Monte Carlo code was developed for the simulation of the light collection in aerogel counters. Monte Carlo results based on measured PTFE reflection coefficient and aerogel absorption and scattering lengths are in agreement with experiment.
A system of aerogel Cherenkov counters with light collection on wavelength shifters is suggested for particle identification in the KEDR detector. This system will be able to work in 1.8 T magnetic ...field and will provide pion/kaon identification in the momentum region of 0.6 1.5 GeV/c (1.05 refractive index aerogel). A distinctive feature of these counters is the use of wavelength shifters of two types – `blue' and `green', and the use of micro-channel plate photo-tubes with multi-alcali photocathode. Owing to this, it is possible to reduce essentially the photocathode surface comparing with the direct light collection. Results of Monte Carlo calculations are presented.
The recent development of new processes has led to the fabrication of small density silica aerogel with high optical quality. The BaBar experiment, in order to achieve its physics program, requires a ...good pion/kaon identification capability up to 4.3 GeV/
c able to work inside a 1.5 T magnetic field. An aerogel threshold counter using the combination of two refractive indices (1.055 and 1.007) can be used to complete the angular coverage of the particle identification system in the forward region. Different detector geometries read out by two photodetector types (fine mesh phototubes and hybryd photodiodes) have been considered and tested in a CERN beam test.