Latest findings on large-scale cosmic ray anisotropy from the GRAPES-3 experiment
Cosmic ray anisotropy at various scales has been observed over the past decade by multiple experiments in both the Northern and Southern Hemispheres. The GRAPES-3 experiment, located at 11.4 degrees North, is well positioned to study a significant portion of both hemispheres, covering nearly 70 percent of the sky at TeV energies. Observing large-scale anisotropy is particularly challenging since the effect is extremely small, measuring less than 0.1%, while detector and atmospheric influences can reach up to 5% and must be carefully mitigated. Using one year of data collected by GRAPES-3 between January 1, 2013, and December 31, 2013, we apply the iterative maximum likelihood method to extract the large-scale anisotropy. The detection significance reaches 6 standard deviations. The results, along with a comparison to findings from other experiments, are described in this proceeding.
Authors
- K. Ramesh
- Y. Hayashi
- Fahim Varsi (ORCID: https://orcid.org/0000-0001-7795-0467)
- Medha Chakraborty (ORCID: https://orcid.org/0000-0003-2211-6912)
- B. Hariharan (ORCID: https://orcid.org/0000-0002-4496-7163)
- D. Pattanaik (ORCID: https://orcid.org/0000-0002-1380-1187)
- M. Rameez (ORCID: https://orcid.org/0000-0001-5023-5631)
- P. K. Mohanty (ORCID: https://orcid.org/0000-0002-3435-7492)
- P.K. Nayak (ORCID: https://orcid.org/0000-0002-6223-4385)
- Manish Talwar (ORCID: https://orcid.org/0000-0002-7266-3300)
- Amit Kumar Jain (ORCID: https://orcid.org/0000-0001-8498-8375)
- S. R. Dugad
- S. Kawakami
- S. K. Gupta
- A. Oshima
- P. Jagadeesan
Publication Details
- Published
- 2025-09-23
- DOI
- https://doi.org/10.22323/1.501.0216
- Primary Topic
- Astrophysics and Cosmic Phenomena
- Type
- article
- Field-Weighted Citation Impact
- 0.00