Estimates of multipolar coefficients to search for cosmic ray anisotropies with non-uniform or partial sky coverage - IN2P3 - Institut national de physique nucléaire et de physique des particules Access content directly
Journal Articles Journal of Cosmology and Astroparticle Physics Year : 2008

Estimates of multipolar coefficients to search for cosmic ray anisotropies with non-uniform or partial sky coverage

Abstract

We study the possibility to extract the multipolar moments of an underlying distribution from a set of cosmic rays observed with non-uniform or even partial sky coverage. We show that if the degree is assumed to be upper bounded by $L$, each multipolar moment can be recovered whatever the coverage, but with a variance increasing exponentially with the bound $L$ if the coverage is zero somewhere. Despite this limitation, we show the possibility to test predictions of a model without any assumption on $L$ by building an estimate of the covariance matrix seen through the exposure function.

Dates and versions

in2p3-00178861 , version 1 (12-10-2007)

Identifiers

Cite

P. Billoir, O. Deligny. Estimates of multipolar coefficients to search for cosmic ray anisotropies with non-uniform or partial sky coverage. Journal of Cosmology and Astroparticle Physics, 2008, 02, pp.009. ⟨10.1088/1475-7516/2008/02/009⟩. ⟨in2p3-00178861⟩
10 View
0 Download

Altmetric

Share

Gmail Mastodon Facebook X LinkedIn More