TY  - CONF
AU  - Meyer, Manuel
AU  - Horns, Dieter
TI  - Indications for a suppression of pair production at very high energies
IS  - DESY-PROC-2011-04
CY  - Hamburg
PB  - Deutsches Elektronen-Synchrotron, DESY
M1  - PUBDB-2016-01117
M1  - DESY-PROC-2011-04
SP  - 151-157
PY  - 2011
AB  - The transparency of the universe for very high energy (VHE) photons is limited due to pair-production with low energy photons of the extra galactic background light (EBL) in the ultra-violet to infrared wavelength band. Here, we use 58 energy spectra from VHE emitting active galactic nuclei (AGN) from redshift 0.004 to 0.536 to search for signatures of deviations from the minimum expected opacity. A statistical study of the individual measurements reveals indications for an overcorrection of AGN spectra with current EBL models. Axion like particles are discussed as a possible explanation of the result.
T2  - 7th Patras Workshop on Axions, WIMPs and WISPs
CY  - 27 Jun 2011 - 1 Jul 2011, Mykonos (Greece)
Y2  - 27 Jun 2011 - 1 Jul 2011
M2  - Mykonos, Greece
LB  - PUB:(DE-HGF)8 ; PUB:(DE-HGF)15
DO  - DOI:10.3204/DESY-PROC-2011-04/meyer_manuel
UR  - https://bib-pubdb1.desy.de/record/295201
ER  -