Observation of a Very Energetic Cosmic Ray Well Beyond the Predicted 2.7 K Cutoff in the Primary Energy Spectrum

Hayashida, N.; Honda, K.; Honda, M.; Imaizumi, S.; Inoue, N.; Kadota, K.; Kakimoto, F.; Kamata, K.; Kawaguchi, S.; Kawasumi, N.; Matsubara, Y.; Murakami, Kazuaki; Nagano, M.; Ohoka, H.; Takeda, M.; Teshima, M.; Tsushima, I.; Yoshida, Shigeru; Yoshii, H.

doi:10.1103/physrevlett.73.3491

Cited by 282 publications

(175 citation statements)

References 12 publications

Supporting

Mentioning

167

Contrasting

Order By: Relevance

“…This event, together with an event recorded by the Yakutsk air shower array in May 1989 [5], of estimated energy ∼ 2 × 10 8 TeV, are the two highest energy cosmic rays ever seen. More recent papers [6] report that the Akeno Giant Air Shower Array, an instrument of over 100 scintillation detectors spread over a 100 km 2 area, recorded 2 events in the same energy range.…”

Section: The Highest Energy Cosmic Rays: a Paradoxmentioning

confidence: 99%

The highest energy cosmic rays and new particle physics

Burdman¹,

Halzen²,

Gandhi³

1998

Physics Letters B

View full text Add to dashboard Cite

It has been argued that the observations of cosmic particles with energies in excess of 10 8 TeV represent a puzzle. Its solution requires new astrophysics or new particle physics. We show that the latter is unlikely given that the scale associated with a new particle physics threshold must be of order 1 GeV, not TeV and above, in order to resolve the problem. In most cases such new physics should have been revealed by accelerator experiments. We examine the possibility that the highest energy cosmic rays are initiated by non-standard interactions of neutrinos in the atmosphere. We show that proposals in this direction either violate s-wave unitarity or fall short of producing a sizeable effect by several orders of magnitude.

show abstract

Section: The Highest Energy Cosmic Rays: a Paradoxmentioning

confidence: 99%

The highest energy cosmic rays and new particle physics

Burdman¹,

Halzen²,

Gandhi³

1998

Physics Letters B

View full text Add to dashboard Cite

show abstract

“…In order to provide better coverage of the northern celestial hemisphere, we add a 210 EeV event from the AGASA array [50] and the previously mentioned 320 EeV event from the Fly's Eye detector [46], both with reasonably accurate arrival directions. The observed energies and directions of these 29 events can now be used to sharpen bound (14) in terms of the square of the number a given by (12b).…”

Section: Note Added In Proofmentioning

confidence: 99%

Ultrahigh-energy cosmic-ray bounds on nonbirefringent modified Maxwell theory

2008

View full text Add to dashboard Cite

A particularly simple Lorentz-violating modification of the Maxwell theory of photons maintains gauge invariance, CPT, and renormalization. This modified-Maxwell theory, coupled to standard Dirac particles, involves nineteen dimensionless "deformation parameters." Ten of these parameters lead to birefringence and are already tightly constrained by astrophysics. New bounds on the remaining nine nonbirefringent parameters can be obtained from the absence of vacuum Cherenkov radiation for ultrahigh-energy cosmic rays (UHECRs). Using selected UHECR events recorded at the Pierre Auger Observatory and assigning pseudo-random directions (i.e., assuming large-scale isotropy), Cherenkov bounds are found at the 10 −18 level, which improve considerably upon current laboratory bounds. Future UHECR observations may reduce these Cherenkov bounds to the 10 −23level.An Addendum with two-sided bounds has been published separately [Phys. Rev. D 77, 117901 (2008), arXiv:0806.4351].

show abstract

“…The energy spectrum of the primary cosmic rays is remarkable, in that, it can be described by a simple power law over nearly 10 decades in energy, with only two significant changes in the exponent at ~ 3 x 10 15 termed the knee and ~ 3x10 18 eV termed the ankle. Despite a great deal of progress being made in recent times, a comprehensive understanding of the nature of the sources and the acceleration mechanism(s) responsible for the primary cosmic rays continues to elude us.…”

Section: Energy Spectrum and Compositionmentioning

confidence: 99%

“…The study of the highest energy cosmic radiation has been vigorously pursued, by using several large area extensive air shower (EAS) arrays with collection areas exceeding hundreds of km 2 , to directly detect the extremely low fluxes of < 1 km -2 sr -1 century -1 expected of these particles [14,15]. Recently, two new giant experiments, namely, the Pierre Auger Observatory (PAO) [16] and the Telescope Array (TA) [17] have been set up with effective collection areas in excess of 1000 km 2 for the study of the highest energy cosmic rays.…”

Section: Diffuse γ γ γ γ γ-Ray Flux ~ 100 Tevmentioning

confidence: 99%

High Energy Astroparticle Physics at Ooty and the GRAPES-3 Experiment

Gupta¹

2014

Proceedings of the Indian National Science Academy

View full text Add to dashboard Cite

The astroparticle studies at Ooty have their roots going way back into the fifties, when studies using cosmic rays were initiated with cloud chambers of progressively larger sizes as the primary detector and measuring device to obtain properties of hadrons at high energies. This study was subsequently strengthened with the installation of a total absorption calorimeter and a modest extensive air shower array to probe the composition of the primary cosmic rays to very high energies. The discovery of pulsars provided a thrust for the exploration of these compact objects as the sources of γ-rays at TeV energies with the aid of atmospheric Cerenkov detectors in the seventies. With the rapid technological advances occurring during the subsequent years in detectors, electronics and computers, physicists world-wide were able to set up very large and remarkably sensitive experiments that were hard to imagine a decade earlier. With the increasing sophistication and complexity the modern experiments require participation of very large teams of scientists. This development has made the formation of collaboration of large number of physicists both experimental and theoretical, engineers, technicians etc., from a number of institutions and universities, a prerequisite for setting up any major experimental facility. The GRAPES-3 experiment is a collaboration of 34 scientists from 13 institutions, including 8 from India and 5 from Japan. The GRAPES-3 experiment contains a dense extensive air shower array operating with ~ 400 scintillator detectors and a 560 m 2 tracking muon detector (Em > 1 GeV), at Ooty in India. 25 % of scintillator detectors are instrumented with two fast photomultiplier tubes (PMTs) for extending the dynamic range to ~ 5x10 3 particles m -2. The scintillators, signal processing electronics and data recording systems were fabricated in-house to cut costs and optimize performance. The muon multiplicity distribution of the EAS is used to probe the composition of primary cosmic rays below the 'knee', with an overlap with direct measurements. Search for multi-TeV γ-rays from point sources is done with the aid of the muon detector. A good angular resolution of 0.7 o at 30 TeV, is measured from shadow of the Moon on the isotropic flux of cosmic rays. Sensitive limit on the diffuse flux of 100 TeV γ-rays is placed by using muon detector to filter out the charged cosmic ray background. The tracking muon detector allows sensitive measurements on the coronal mass ejections and solar flares through Forbush decrease events. We have major expansion plans to enhance the sensitivity of the GRAPES-3 experiment in the areas listed above. PACS

show abstract

Observation of a Very Energetic Cosmic Ray Well Beyond the Predicted 2.7 K Cutoff in the Primary Energy Spectrum

Cited by 282 publications

References 12 publications

The highest energy cosmic rays and new particle physics

The highest energy cosmic rays and new particle physics

Ultrahigh-energy cosmic-ray bounds on nonbirefringent modified Maxwell theory

High Energy Astroparticle Physics at Ooty and the GRAPES-3 Experiment

Contact Info

Product

Resources

About