Zenith angle dependence of pressure effect in GRAPES-3 muon telescope

Date Issued
2022-03-18
Author(s)
Zuberi, M.
Ahmad, S.
Chakraborty, M.
Chandra, A.
Dugad, S. R.
Goswami, U. D.
Gupta, S. K.
Hariharan, B.
Hayashi, Y.
Jagadeesan, P.
Jain, A.
Jain, P.
Kawakami, S.
Kojima, H.
Mahapatra, S.
Mohanty, P. K.
Moharana, R.
Muraki, Y.
Nayak, P. K.
Nonaka, T.
Oshima, A.
Pant, B. P.
Pattanaik, D.
Pradhan, G. S.
Rakshe, P. S.
Rameez, M.
Ramesh, K.
Reddy, L. V.
Sahoo, R.
Scaria, R.
Shibata, S.
Soni, J.
Tanaka, K.
Varsi, F.
Abstract
A large area (560 m2) muon telescope in the GRAPES-3 experiment at Ooty, India records muon intensity at high cutoff rigidities (Rc) varies from 14–32 GV along 169 independent directions spanning a field of view of 2.3 sr. The threshold energy of the recorded muons is sec(θ) GeV along a direction with a zenith angle (θ) and with the average angular accuracy of ∼4σ. The directional capabilities of the muon telescope are exploited for studying the effect of atmospheric pressure on the muon flux as a function of Rc. It is observed that the barometric coefficients relationship with logarithmic Rc can be well described by second-order polynomial function with a high Spearman Rank correlation coefficient of 0.99.