Measurement of the UHECR Energy Spectrum from Hybrid Data of the Pierre Auger Observatory

Three years of data collected with the fluorescence detector in coincidence with at least one station of the surface detector array ('hybrid data') are used to measure the flux and energy spectrum of cosmic rays above about 10^{18}eV. The hybrid measurement extends the spectrum measured with the surface detector data alone towards lower energies, and provides a cross-check in the overlap region with an independent analysis method. The determination of the aperture of the fluorescence detector and of the live-time, which are key features of this measurement, is illustrated in detail. Our estimates of the corresponding systematic uncertainties are given.

Note:

To appear in the proceedings of 30th International Cosmic Ray Conference (ICRC 2007), Merida, Yucatan, Mexico, 3-11 Jul 2007 - 4pp

References(2)

Figures(8)

Simulation of the fluorescence detector of the Pierre Auger Observatory

L. Prado
(
- Campinas State U. and
- Adelaide U. and
- INFN, Aquila and
- L'Aquila U. and
- Rio de Janeiro, CBPF and
- Niteroi, Fluminense U.
)
,
B.R. Dawson
(
- Campinas State U. and
- Adelaide U. and
- INFN, Aquila and
- L'Aquila U. and
- Rio de Janeiro, CBPF and
- Niteroi, Fluminense U.
)
,
S. Petrera
(
- Campinas State U. and
- Adelaide U. and
- INFN, Aquila and
- L'Aquila U. and
- Rio de Janeiro, CBPF and
- Niteroi, Fluminense U.
)
,
R.C. Shellard
(
- Campinas State U. and
- Adelaide U. and
- INFN, Aquila and
- L'Aquila U. and
- Rio de Janeiro, CBPF and
- Niteroi, Fluminense U.
)
,
M.G. do Amaral
(
- Campinas State U. and
- Adelaide U. and
- INFN, Aquila and
- L'Aquila U. and
- Rio de Janeiro, CBPF and
- Niteroi, Fluminense U.
)

et al.

- Nucl.Instrum.Meth.A 545 (2005) 632-642
•
DOI:
- 10.1016/j.nima.2005.01.346

An upper limit to the photon fraction in cosmic rays above $10^{19}$ -eV from the Pierre Auger Observatory

Pierre Auger

Collaboration

•

J. Abraham

et al.

- Astropart.Phys. 27 (2007) 155-168
•
e-Print:
- astro-ph/0606619
•
DOI:
- 10.1016/j.astropartphys.2006.10.004