THE VATLY CHERENKOV DETECTOR AND ITS RESPONSE TO ELECTRONS AND MUONS

NGUYEN THI THAO1, PHAM TUAN ANH1, PIERRE DARRIULAT1, PHAM NGOC DIEP1, PHAM NGOC DONG1, NGUYEN VAN HIEP1, DO THI HOAI1, PHAM THI TUYET NHUNG1
1 Institute for Nuclear Science and Technology, 179 Hoang Quoc Viet, Cau Giay, Hanoi

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Abstract

A replica of one of the 1660 Cherenkov detectors used in the ground array of the Pierre Auger Cosmic Ray Observatory in Argentina has been constructed on the roof of the VATLY astrophysics laboratory in Ha Noi (Viet Nam). I report on cosmic ray measurements made using this detector, including its response to relativistic feed-through muons. Particular emphasis is on event pairs occurring within a small time window. Data include time autocorrelation and charge spectra of the detected signals. They are analyzed in terms of muon decays in the water volume of the Cherenkov tank and of the probability to detect two secondaries of a same shower. The former provide useful information on the response of the detector to small signals. The latter measure the width of the lateral distribution functions of extensive air showers in the TeV region.

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References

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