Phone: +44 (0) 113 2333888
Email: a.a.watsonleeds.ac.uk
WWW: Web Site

I have interests in all aspects of high energy astroparticle physics, with special interest in the very highest energy cosmic rays. I was head of the Haverah Park extensive air shower project from 1976 until its closure in the early 1990s. This project produced the first evidence for the absence of the celebrated Greisen-Kuzmin-Zatsepin cut-off in the cosmic ray energy spectrum above 4.10¹⁹ eV, in addition to providing key data relating to the arrival distribution and mass composition of cosmic rays.
The Haverh Park group was also involved in searches for gamma ray sources at energies around 1 PeV. More recently research interests of broadened to embrace work at the South Pole aimed at elucidating the mass composition of cosmicr rays in the region of the knee at 1 PeV using a shower array and the AMANDA neutrino detector.
Interest in the highest energy cosmic rays continues through collaboration with the Auger project, a world wide effort to construct detectors of 3000 sqkm in Argentina and the USA to push knowledge of the highest energy cosmic rays still further.

Ongoing Scientific Projects:

• Pierre Auger Observatory (AUGER)

• Observatory aims to find the origin of cosmic rays, Chicago Tribune

• Workshop, Astroparticle Physics Symposium: "The High Energy Frontier" (organizer)
• KICP Workshop, CroninFest: James Cronin Symposium
• KICP Seminar, The mass composition of cosmic rays above 10^17eV
• KICP Seminar, The Highest Energy Particles in Nature
• KICP Seminar, The Energy Spectrum and Mass Composition of Cosmic Rays at High Energy

2013 | 2012 | 2011 | 2010 | 2009 | 2008 | 2007 | 2005 | 2004


Latest Journal Publications

1. "Constraints on the Origin of Cosmic Rays above 1018 eV from Large-scale Anisotropy Searches in Data of the Pierre Auger Observatory", The Astrophysical Journal Letters, Volume 762, Issue 1, article id. L13, 8 pp. (2013) (Jan 2013)
2. "Constraints on the Origin of Cosmic Rays above 1018 eV from Large-scale Anisotropy Searches in Data of the Pierre Auger Observatory", The Astrophysical Journal Letters, Volume 762, Issue 1, article id. L13, 8 pp. (2013) (Jan 2013)
3. "A Search for Point Sources of EeV Neutrons", The Astrophysical Journal, Volume 760, Issue 2, article id. 148, 11 pp. (2012) (Dec 2012)
4. "Large-scale Distribution of Arrival Directions of Cosmic Rays Detected Above 1018 eV at the Pierre Auger Observatory", The Astrophysical Journal Supplement, Volume 203, Issue 2, article id. 34, 20 pp. (2012) (Dec 2012)
5. "A Search for Point Sources of EeV Neutrons", The Astrophysical Journal, Volume 760, Issue 2, article id. 148, 11 pp. (2012) (Dec 2012)
6. "Results of a self-triggered prototype system for radio-detection of extensive air showers at the Pierre Auger Observatory", Journal of Instrumentation, Volume 7, Issue 11, pp. P11023 (2012) (Nov 2012)
7. "Antennas for the detection of radio emission pulses from cosmic-ray induced air showers at the Pierre Auger Observatory", Journal of Instrumentation, Volume 7, Issue 10, pp. P10011 (2012) (Oct 2012)
8. "Search for Point-like Sources of Ultra-high Energy Neutrinos at the Pierre Auger Observatory and Improved Limit on the Diffuse Flux of Tau Neutrinos", The Astrophysical Journal Letters, Volume 755, Issue 1, article id. L4, 7 pp. (2012) (Aug 2012)
9. "Measurement of the Proton-Air Cross Section at s=57TeV with the Pierre Auger Observatory", Physical Review Letters, vol. 109, Issue 6, id. 062002 (Aug 2012)
10. "Erratum to "The Lateral Trigger Probability function for the Ultra-High Energy Cosmic Ray Showers detected by the Pierre Auger Observatory" [Astroparticle Physics 35 (2011) 266-276]", Astroparticle Physics, Volume 35, Issue 10, p. 681-684 (May 2012)
11. "Erratum to "The Lateral Trigger Probability function for the Ultra-High Energy Cosmic Ray Showers detected by the Pierre Auger Observatory" [Astroparticle Physics 35 (2011) 266-276]", Astroparticle Physics, Volume 35, Issue 10, p. 681-684 (May 2012)
12. "Description of atmospheric conditions at the Pierre Auger Observatory using the Global Data Assimilation System (GDAS)", Astroparticle Physics, Volume 35, Issue 9, p. 591-607 (Apr 2012)
13. "Description of atmospheric conditions at the Pierre Auger Observatory using the Global Data Assimilation System (GDAS)", Astroparticle Physics, Volume 35, Issue 9, p. 591-607 (Apr 2012)
14. "A search for anisotropy in the arrival directions of ultra high energy cosmic rays recorded at the Pierre Auger Observatory", Journal of Cosmology and Astroparticle Physics, Issue 04, id. 040 (2012) (Apr 2012)
15. "Publisher's Note: Search for ultrahigh energy neutrinos in highly inclined events at the Pierre Auger Observatory [Phys. Rev. D 84, 122005 (2011)]", Physical Review D, vol. 85, Issue 2, id. 029902 (Jan 2012)
16. "Search for signatures of magnetically-induced alignment in the arrival directions measured by the Pierre Auger Observatory", Astroparticle Physics, Volume 35, Issue 6, p. 354-361 (Jan 2012)
17. "Search for signatures of magnetically-induced alignment in the arrival directions measured by the Pierre Auger Observatory", Astroparticle Physics, Volume 35, Issue 6, p. 354-361 (Jan 2012)
18. "The Lateral Trigger Probability function for the Ultra-High Energy Cosmic Ray showers detected by the Pierre Auger Observatory", Astroparticle Physics, Volume 35, Issue 5, p. 266-276 (Dec 2011)
19. "The Lateral Trigger Probability function for the Ultra-High Energy Cosmic Ray showers detected by the Pierre Auger Observatory", Astroparticle Physics, Volume 35, Issue 5, p. 266-276 (Dec 2011)
20. "Search for ultrahigh energy neutrinos in highly inclined events at the Pierre Auger Observatory", Physical Review D, vol. 84, Issue 12, id. 122005 (Dec 2011)