Speaker
Julien Aublin
(urn:Google)
Description
We present the results of a search for small scale anisotropies in the distribution of arrival directions of ultra-high energy cosmic rays recorded at the Pierre Auger Observatory. The data set, gathered in ten years of operation, includes arrival directions with zenith angles up to $80^\circ$, and is about three times larger than that used in earlier studies. We update the test based on correlations with active galactic nuclei (AGNs) from the V\'eron-Cetty and V\'eron catalog, which does not yield a significant indication of anisotropy with the present data set. We perform a blind search for localized excess fluxes and for self-clustering of arrival directions at angular scales up to $30^\circ$ and for different energy thresholds between 40 EeV and 80 EeV. We search for correlations with the Galactic Center, the Galactic Plane and the Super-Galactic Plane. We also examine the correlation of arrival directions with relatively nearby galaxies in the 2MRS catalog, AGNs detected by Swift-BAT, a sample of radio galaxies with jets and with the Centaurus A galaxy. None of the searches shows a statistically significant evidence of anisotropy. The two largest departures from isotropy that were found have a post-trial probability $\approx 1.4$\%. One is for cosmic rays with energy above 58 EeV that arrive within $15^\circ$ of the direction toward Centaurus A. The other is for arrival directions within $18^\circ$ of Swift-BAT AGNs closer than 130 Mpc and brighter than $10^{44}$ erg/s, with the same energy threshold.
| Registration number following "ICRC2015-I/" | 0570 |
|---|---|
| Collaboration | Pierre Auger |
Primary author
Julien Aublin
(urn:Google)
