Maximum likelihood method for cross-correlations with astrophysical sources

Ronnie Jansson, Glennys R. Farrar

    Research output: Contribution to journalArticle

    Abstract

    We generalize the maximum likelihood-type method used to study cross-correlations between a catalog of candidate astrophysical sources and ultrahigh energy cosmic rays (UHECRs), to allow for differing source luminosities. The new method is applicable to any sparse dataset such as UHE gamma rays or astrophysical neutrinos. Performance of the original and generalized techniques is evaluated in simulations of various scenarios. Applying the new technique to data, we find an excess correlation of about nine events between HiRes UHECRs and known BLLacs, with a 6 × 10 -5 probability of such a correlation arising by chance.

    Original languageEnglish (US)
    Article number017
    JournalJournal of Cosmology and Astroparticle Physics
    Volume2008
    Issue number6
    DOIs
    StatePublished - Jun 1 2008

    Fingerprint

    cross correlation
    cosmic rays
    astrophysics
    catalogs
    neutrinos
    luminosity
    gamma rays
    energy
    simulation

    Keywords

    • High energy photons
    • Ultra high energy cosmic rays
    • Ultra high energy photons and neutrinos

    ASJC Scopus subject areas

    • Physics and Astronomy(all)

    Cite this

    Maximum likelihood method for cross-correlations with astrophysical sources. / Jansson, Ronnie; Farrar, Glennys R.

    In: Journal of Cosmology and Astroparticle Physics, Vol. 2008, No. 6, 017, 01.06.2008.

    Research output: Contribution to journalArticle

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