Upper limit on the cosmic-ray photon flux above 1019eV using the surface detector of the Pierre Auger Observatory

The research horizons of the Pierre Auger Cosmic-Ray Observatory widened when the collaboration found exotic (atmospheric) phenomena in both its Fluorescence Detector (FD) and Surface Detector (SD). The Cosmology and Geophysics task force of the Auger Collaboration focused some of its attention on these highly energetic events, which are correlated to some of the most intense convective thunderstorm systems in the world. In this proceeding, we compare the signal of these exotic events and the signal of cosmic rays, as seen in the FD and the SD. The FD has triggered on numerous transient luminous events, dubbed “elves" since their first observation in 2005. The SD observed peculiar events with radially expanding footprints, which are correlated with lightning strikes reconstructed by the World Wide Lightning Location Network (WWLLN). The traced signals of both of these atmospheric events last longer in time than cosmic ray signals. The footprints are much larger; typically more SD stations (or more FD pixels) contribute to the observations.

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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.

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Search for UHE neutrinos in coincidence with LIGO GW150914 event with the Pierre Auger Observatory

Proceedings of the International Astronomical Union ◽

10.1017/s1743921317001454 ◽

2016 ◽

Vol 12 (S324) ◽

pp. 295-298

Author(s):

Lili Yang ◽

Keyword(s):

Energy Range ◽

Gravitational Wave ◽

High Energy ◽

Universal Time ◽

Pierre Auger Observatory ◽

Ultra High Energy ◽

Upper Limit ◽

Surface Detector ◽

High Energy Regime

AbstractThe first gravitational wave transient GW150914 was observed by Advanced LIGO on September 14th, 2015 at 09:50:45 Universal Time. In addition to follow-up electromagnetic observations, the detection of neutrinos will probe deeply and more on the nature of astrophysical sources, especially in the ultra-high energy regime. Neutrinos in the EeV energy range were searched in data collected at the surface detector of the Pierre Auger Observatory within ± 500 s and 1 day after the GW150914 event. No neutrino candidates were found. Based on this non-observation, we derive the first and only neutrino fluence upper limit at EeV energies for this event at 90% CL, and report constraints on existence of accretion disk around mergers.

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Recent results from the Pierre Auger Observatory

EPJ Web of Conferences ◽

10.1051/epjconf/201920808001 ◽

2019 ◽

Vol 208 ◽

pp. 08001 ◽

Cited By ~ 2

Author(s):

Sergio Petrera

Keyword(s):

Energy Spectrum ◽

Cosmic Rays ◽

Large Scale ◽

Cosmic Ray ◽

Pierre Auger Observatory ◽

Mass Composition ◽

Arrival Direction ◽

Wide Range ◽

Surface Detector

In this paper some recent results from the Pierre Auger Collaboration are presented. These are the measurement of the energy spectrum of cosmic rays over a wide range of energies (1017.5 to above 1020 eV), studies of the cosmic-ray mass composition with the fluorescence and surface detector of the Observatory, the observation of a large-scale anisotropy in the arrival direction of cosmic rays above 8 × 1018 eV and indications of anisotropy at intermediate angular scales above 4 × 1019 eV. The astrophysical implications of the spectrum and composition results are also discussed. Finally the progress of the upgrade of the Observatory, AugerPrime is presented.

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Measurement of the cosmic ray spectrum with the Pierre Auger Observatory

EPJ Web of Conferences ◽

10.1051/epjconf/201920901029 ◽

2019 ◽

Vol 209 ◽

pp. 01029

Author(s):

Daniela Mockler

Keyword(s):

Cosmic Rays ◽

Cosmic Ray ◽

High Energy ◽

Pierre Auger Observatory ◽

Detector Array ◽

Data Sets ◽

Fluorescence Detector ◽

High Energy Cosmic Rays ◽

Systematic Uncertainties ◽

Surface Detector

The flux of ultra-high energy cosmic rays above 3×1017 eV has been measured with unprecedented precision at the Pierre Auger Observatory. The flux of the cosmic rays is determined by four different measurements. The surface detector array provides three data sets, two formed by dividing the data into two zenith angle ranges, and one obtained from a nested, denser detector array. The fourth measurement is obtained with the fluorescence detector. By combing all four data sets, the all-sky flux of cosmic rays is determined. The spectral features are discussed in detail and systematic uncertainties are addressed.

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The energy spectrum of cosmic rays beyond the turn-down around $$\varvec{10^{17}}$$ eV as measured with the surface detector of the Pierre Auger Observatory

The European Physical Journal C ◽

10.1140/epjc/s10052-021-09700-w ◽

2021 ◽

Vol 81 (11) ◽

Author(s):

P. Abreu ◽

M. Aglietta ◽

J. M. Albury ◽

I. Allekotte ◽

A. Almela ◽

...

Keyword(s):

Cosmic Rays ◽

Precise Measurement ◽

Spectral Feature ◽

Cosmic Ray ◽

Energy Scale ◽

Pierre Auger Observatory ◽

Single Measurement ◽

Surface Detector ◽

Single Detector ◽

Detector Type

AbstractWe present a measurement of the cosmic-ray spectrum above 100 PeV using the part of the surface detector of the Pierre Auger Observatory that has a spacing of 750 m. An inflection of the spectrum is observed, confirming the presence of the so-called second-knee feature. The spectrum is then combined with that of the 1500 m array to produce a single measurement of the flux, linking this spectral feature with the three additional breaks at the highest energies. The combined spectrum, with an energy scale set calorimetrically via fluorescence telescopes and using a single detector type, results in the most statistically and systematically precise measurement of spectral breaks yet obtained. These measurements are critical for furthering our understanding of the highest energy cosmic rays.

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Upper limit on the cosmic-ray photon fraction at EeV energies from the Pierre Auger Observatory

Astroparticle Physics ◽

10.1016/j.astropartphys.2009.04.003 ◽

2009 ◽

Vol 31 (6) ◽

pp. 399-406 ◽

Cited By ~ 94

Author(s):

J. Abraham ◽

P. Abreu ◽

M. Aglietta ◽

C. Aguirre ◽

E.J. Ahn ◽

...

Keyword(s):

Cosmic Ray ◽

Pierre Auger Observatory ◽

Upper Limit

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Measurements of Horizontal Air Showers with the Auger Engineering Radio Array

EPJ Web of Conferences ◽

10.1051/epjconf/201921602001 ◽

2019 ◽

Vol 216 ◽

pp. 02001 ◽

Cited By ~ 1

Author(s):

Marvin Gottowik

Keyword(s):

Cosmic Rays ◽

Antenna Array ◽

Radio Signal ◽

Cosmic Ray ◽

Pierre Auger Observatory ◽

Large Area ◽

Air Showers ◽

Radio Detection ◽

Surface Detector ◽

Electromagnetic Component

The Pierre Auger Observatory is the largest observatory for the detection of cosmic rays. With the Auger Engineering Radio Array (AERA) we measure the emitted radio signal of extensive air showers and reconstruct properties of the primary cosmic rays. For horizontal air showers (zenith angles larger than 60°) the signal is distributed over a large area of more than several km2. Therefore, detection of air showers using a sparse radio antenna array, compatible with the 1500 m distance between the 1600 surface detector stations, is possible. The radio technique is sensitive to the electromagnetic component of air showers. Combining radio detection with particle information from the surface detector of the Observatory, which at large zenith angles mostly detects muons, allows to study the cosmic ray composition for horizontal air showers.

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