Cross-correlating 2MASS Redshift Survey galaxies with the ultrahigh energy cosmic ray flux from Pierre Auger Observatory

The Pierre Auger Observatory is the largest ultrahigh-energy cosmic ray observatory in the world. The huge amount of high quality data collected since 2004 up to now led to great improvements in our knowledge of the ultra-energetic cosmic rays. The suppression of the cosmic-ray flux at highest energies was clearly established, and the extra-galactic origin of these particles was confirmed. On the other hand, measurements of the depth of shower maximum indicate a puzzling trend in the mass composition of cosmic rays at energy around the ankle up to the highest energy. The just started upgrade of the Observatory, dubbed AugerPrime, will improve the identification of the mass of primaries allowing us to disentangle models of origin and propagation of cosmic rays.

Download Full-text

Atmospheric Monitoring at a Cosmic Ray Observatory - a long-lasting endeavour

EPJ Web of Conferences ◽

10.1051/epjconf/201919702001 ◽

2019 ◽

Vol 197 ◽

pp. 02001

Author(s):

Bianca Keilhauer

Keyword(s):

Cosmic Rays ◽

Cosmic Ray ◽

Extensive Air Showers ◽

Pierre Auger Observatory ◽

Ultrahigh Energy ◽

Atmospheric Conditions ◽

Air Showers ◽

Atmospheric Monitoring ◽

Surface Detector ◽

Planning And Construction

The Pierre Auger Observatory for detecting ultrahigh energy cosmic rays has been founded in 1999. After a main planning and construction phase of about five years, the regular data taking started in 2004, but it took another four years until the full surface detector array was deployed. In parallel to the main detectors of the Observatory, a comprehensive set of instruments for monitoring the atmospheric conditions above the array was developed and installed as varying atmospheric conditions influence the development and detection of extensive air showers. The multitude of atmospheric monitoring installations at the Pierre Auger Observatory will be presented as well as the challenges and efforts to run such instruments for several decades.

Download Full-text

Comparison of the ultrahigh energy cosmic ray flux observed by AGASA, HiRes, and Auger

Physical Review D ◽

10.1103/physrevd.74.043001 ◽

2006 ◽

Vol 74 (4) ◽

Cited By ~ 8

Author(s):

B. M. Connolly ◽

S. Y. BenZvi ◽

C. B. Finley ◽

A. C. O’Neill ◽

S. Westerhoff

Keyword(s):

Cosmic Ray ◽

Ultrahigh Energy ◽

Cosmic Ray Flux

Download Full-text

Cosmic ray acceleration to ultrahigh energy in radio galaxies

EPJ Web of Conferences ◽

10.1051/epjconf/201921004002 ◽

2019 ◽

Vol 210 ◽

pp. 04002

Author(s):

James H. Matthews ◽

Anthony R. Bell ◽

Anabella T. Araudo ◽

Katherine M. Blundell

Keyword(s):

Cosmic Rays ◽

Cosmic Ray ◽

Radio Galaxies ◽

Pierre Auger Observatory ◽

Ultrahigh Energy ◽

Cosmic Ray Acceleration ◽

Ultrahigh Energy Cosmic Rays ◽

General Physical ◽

Open Question ◽

Centaurus A

The origin of ultrahigh energy cosmic rays (UHECRs) is an open question. In this proceeding, we first review the general physical requirements that a source must meet for acceleration to 10-100 EeV, including the consideration that the shock is not highly relativistic. We show that shocks in the backflows of radio galaxies can meet these requirements. We discuss a model in which giant-lobed radio galaxies such as Centaurus A and Fornax A act as slowly-leaking UHECR reservoirs, with the UHECRs being accelerated during a more powerful past episode. We also show that Centaurus A, Fornax A and other radio galaxies may explain the observed anisotropies in data from the Pierre Auger Observatory, before examining some of the difficulties in associating UHECR anisotropies with astrophysical sources.

Download Full-text

PeV Emission of the Crab Nebula: Constraints on the Proton Content in Pulsar Wind and Implications

The Astrophysical Journal ◽

10.3847/1538-4357/ac2ba0 ◽

2021 ◽

Vol 922 (2) ◽

pp. 221

Author(s):

Ruo-Yu Liu ◽

Xiang-Yu Wang

Keyword(s):

Energy Content ◽

Crab Nebula ◽

Cosmic Ray ◽

Ultrahigh Energy ◽

Pulsar Wind Nebulae ◽

Air Shower ◽

Pulsar Wind ◽

The Crab Nebula ◽

Pulsar Winds ◽

Cosmic Ray Flux

Abstract Recently, two photons from the Crab Nebula with energy of approximately 1 PeV were detected by the Large High Altitude Air Shower Observatory (LHAASO), opening an ultrahigh-energy window for studying pulsar wind nebulae (PWNe). Remarkably, the LHAASO spectrum at the highest-energy end shows a possible hardening, which could indicate the presence of a new component. A two-component scenario with a main electron component and a secondary proton component has been proposed to explain the whole spectrum of the Crab Nebula, requiring a proton energy of 1046–1047 erg remaining in the present Crab Nebula. In this paper, we study the energy content of relativistic protons in pulsar winds using the LHAASO data of the Crab Nebula, considering the effect of diffusive escape of relativistic protons. Depending on the extent of the escape of relativistic protons, the total energy of protons lost in the pulsar wind could be 10–100 times larger than that remaining in the nebula presently. We find that the current LHAASO data allow up to (10–50)% of the spindown energy of pulsars being converted into relativistic protons. The escaping protons from PWNe could make a considerable contribution to the cosmic-ray flux of 10–100 PeV. We also discuss the leptonic scenario for the possible spectral hardening at PeV energies.

Download Full-text

RECENT RESULTS FROM THE PIERRE AUGER OBSERVATORY

International Journal of Modern Physics E ◽

10.1142/s0218301311040153 ◽

2011 ◽

Vol 20 (supp01) ◽

pp. 118-131

Author(s):

◽

CAROLA DOBRIGKEIT

Keyword(s):

Energy Spectrum ◽

Cosmic Rays ◽

Cosmic Ray ◽

Pierre Auger Observatory ◽

Detector Array ◽

Average Depth ◽

Ultrahigh Energy ◽

Arrival Direction ◽

Baseline Design ◽

Shower Maximum

The Pierre Auger Observatory in Argentina is the largest cosmic ray detector array ever built. Its main goal is to measure cosmic rays of energy above 1018 eV with unprecedented statistics and precision. Although the construction of its baseline design was completed in mid-2008, the Observatory has been taking data continuously since January 2004. The main results obtained with the Pierre Auger Observatory are presented, with emphasis on the energy spectrum and studies of composition and arrival directions of the ultrahigh energy cosmic rays. Features observed in the energy spectrum are discussed. Results about cosmic ray composition inferred from systematic studies of the average depth of shower maximum and its fluctuations are reviewed. Recent results of studies of arrival direction distributions and correlations with nearby extragalactic objects are presented.

Download Full-text

The Askaryan Radio Array

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312016754 ◽

2012 ◽

Vol 8 (S288) ◽

pp. 115-122

Author(s):

Kara D. Hoffman

Keyword(s):

Neutrino Flux ◽

Austral Summer ◽

Cosmic Ray ◽

High Energy ◽

Pierre Auger Observatory ◽

Ultra High Energy ◽

Performance Requirements ◽

Transparent Media ◽

Order Of Magnitude ◽

Cosmic Ray Flux

AbstractUltra high energy cosmogenic neutrinos could be most efficiently detected in dense, radio frequency (RF) transparent media via the Askaryan effect. Building on the expertise gained by RICE, ANITA and IceCube's radio extension in the use of the Askaryan effect in cold Antarctic ice, we are currently developing an antenna array known as ARA (The Askaryan Radio Array) to be installed in boreholes extending 200 m below the surface of the ice near the geographic South Pole. The unprecedented scale of ARA, which will cover a fiducial area of ≈ 100 square kilometers, was chosen to ensure the detection of the flux of neutrinos suggested by the observation of a drop in high energy cosmic ray flux consistent with the GZK cutoff by HiRes and the Pierre Auger Observatory. Funding to develop the instrumentation and install the first prototypes has been granted, and the first components of ARA were installed during the austral summer of 2010–2011. Within 3 years of commencing operation, the full ARA will exceed the sensitivity of any other instrument in the 0.1-10 EeV energy range by an order of magnitude. The primary goal of the ARA array is to establish the absolute cosmogenic neutrino flux through a modest number of events. This information would frame the performance requirements needed to expand the array in the future to measure a larger number of neutrinos with greater angular precision in order to study their spectrum and origins.

Download Full-text

Measurement of the Cosmic Ray Flux near the Second Knee with the Pierre Auger Observatory

10.22323/1.358.0225 ◽

2019 ◽

Author(s):

Alan Coleman ◽

Keyword(s):

Cosmic Ray ◽

Pierre Auger Observatory ◽

Cosmic Ray Flux

Download Full-text

Superheavy dark matter and ultrahigh-energy cosmic rays

Canadian Journal of Physics ◽

10.1139/p06-035 ◽

2006 ◽

Vol 84 (6-7) ◽

pp. 537-543

Author(s):

R Dick ◽

K M Hopp ◽

K E Wunderle

Keyword(s):

Dark Matter ◽

Cosmic Rays ◽

Early Universe ◽

Cosmic Ray ◽

Pierre Auger Observatory ◽

Ultrahigh Energy ◽

Mass Window ◽

Ultrahigh Energy Cosmic Rays ◽

Superheavy Dark Matter ◽

Arrival Directions

The phase of inflationary expansion in the early Universe produces superheavy relics in a mass window between 1012 and 1014 GeV. Decay or annihilation of these superheavy relics an explain the observed ultrahigh-energy cosmic rays beyond the Greisen–Zatsepin–Kuzmin cutoff. We emphasize that the pattern of cosmic-ray arrival directions seen by the Pierre Auger observatory will decide between the different proposals for the origin of ultrahigh-energy cosmic rays.PACS Nos.: 98.70.Sa, 98.70.–f, 95.35.+d, 14.80.–j

Download Full-text