SciPost Submission Page
Highlights from the GRAPES-3 Experiment
by Mohamed Rameez for the GRAPES-3 Collaboration
Submission summary
| Authors (as registered SciPost users): | Mohamed Rameez |
| Submission information | |
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| Preprint Link: | scipost_202411_00063v1 (pdf) |
| Date submitted: | 2024-11-30 10:49 |
| Submitted by: | Rameez, Mohamed |
| Submitted to: | SciPost Physics Proceedings |
| Proceedings issue: | 22nd International Symposium on Very High Energy Cosmic Ray Interactions (ISVHECRI 2024) |
| Ontological classification | |
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| Academic field: | Physics |
| Specialties: |
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| Approaches: | Experimental, Observational |
Abstract
GRAPES-3 is an air shower array in the Nilgiri mountains in Southern India, consist- ing of a 560 m2 muon telescope (G3MT) made up of proportional counters as well as a 25000 m2 array of 400 plastic scintillator detectors. In operation since 2000, the muon telescope has proven itself to be a sensitive probe of cosmic, solar, heliospheric and at- mospheric phenomena. Recently the observatory has validated its pointing by character- izing the shadow of the moon in data gathered over multiple years. Small angular scale anisotropies have been measured in the arrival directions of cosmic rays, confirming the existence of features reported previously by HAWC and Argo-YBJ. The multiplicity distri- bution of muons measured by G3MT allows the relative composition of proton primaries to be extracted from the all-particle air shower data. The extracted proton spectrum indicates a spectral hardening at ∼ 166 TeV, disfavoring a single power law description of the proton spectrum up to the knee. These emerging capabilities of GRAPES-3 as an astroparticle physics observatory are expected to be further enhanced by the completion of a new muon telescope, presently under construction. This will double the effective area over which the muon component of air showers can be measured.