TY  - GEN
A1  - Angüner, Ekrem Oǧuzhan
A1  - Aharonian, Felix A.
A1  - Bordas, Pol
A1  - Casanova, Sabrina
A1  - Hoischen, Clemens
A1  - Oya, I.
A1  - Ziegler, A.
T1  - HESS J1826-130
BT  - a very hard gamma-Ray spectrum source in the Galactic Plane
T2  - AIP conference proceedings / American Institute of Physics
N2  - HESS J1826-130 is an unidentified hard spectrum source discovered by H.E.S.S. along the Galactic plane, the spectral index being Gamma = 1.6 with an exponential cut-off at about 12 TeV. While the source does not have a clear counterpart at longer wavelengths, the very hard spectrum emission at TeV energies implies that electrons or protons accelerated up to several hundreds of TeV are responsible for the emission. In the hadronic case, the VHE emission can be produced by runaway cosmic-rays colliding with the dense molecular clouds spatially coincident with the H.E.S.S. source.
Y1  - 2017
SN  - 978-0-7354-1456-3
U6  - https://doi.org/10.1063/1.4968928
SN  - 0094-243X
SN  - 1551-7616
VL  - 1792
IS  - 1
PB  - American Institute of Physics
CY  - Melville
ER  - 
TY  - CHAP
A1  - Reimer, O.
A1  - Aharonian, Felix A.
A1  - Hinton, J.
A1  - Hofmann, W.
A1  - Hoppe, S.
A1  - Raue, M.
A1  - Reimer, A.
T1  - VHE gamma-rays from Westerlund 2 and implications for the inferred energetics
N2  - The H.E.S.S. collaboration recently reported the discovery of VHE γ-ray emission coincident with the young stellar cluster Westerlund 2. This system is known to host a population of hot, massive stars, and, most particularly, the WR binary WR 20a. Particle acceleration to TeV energies in Westerlund 2 can be accomplished in several alternative scenarios, therefore we only discuss energetic constraints based on the total available kinetic energy in the system, the actual mass loss rates of respective cluster members, and implied gamma-ray production from processes such as inverse Compton scattering or neutral pion decay. From the inferred gammaray luminosity of the order of 1035erg/s, implications for the efficiency of converting available kinetic energy into non-thermal radiation associated with stellar winds in the Westerlund 2 cluster are discussed under consideration of either the presence or absence of wind clumping.
Y1  - 2007
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-18172
ER  - 
TY  - JOUR
A1  - Abdalla, Hassan E.
A1  - Adam, Remi
A1  - Aharonian, Felix A.
A1  - Benkhali, Faical Ait
A1  - Angüner, Ekrem Oǧuzhan
A1  - Arakawa, Masanori
A1  - Arcaro, C
A1  - Armand, Catherine
A1  - Armstrong, T.
A1  - Egberts, Kathrin
T1  - Very high energy γ-ray emission from two blazars of unknown redshift and upper limits on their distance
JF  - Monthly Notices of the Royal Astronomical Society
N2  - We report on the detection of very high energy (VHE; E > 100 GeV) gamma-ray emission from the BL Lac objects KUV 00311-1938 and PKS 1440-389 with the High Energy Stereoscopic System (H.E.S.S.). H.E.S.S. observations were accompanied or preceded by multiwavelength observations with Fermi/LAT, XRT and UVOT onboard the Swift satellite, and ATOM. Based on an extrapolation of the Fermi/LAT spectrum towards the VHE gamma-ray regime, we deduce a 95 per cent confidence level upper limit on the unknown redshift of KUV 00311-1938 of z < 0.98 and of PKS 1440-389 of z < 0.53. When combined with previous spectroscopy results, the redshift of KUV 00311-1938 is constrained to 0.51 <= z < 0.98 and of PKS 1440-389 to 0.14 (sic) z < 0.53.
KW  - BL Lacertae objects: individual
KW  - galaxies: high-redshift
KW  - gamma-rays: general
KW  - Resolved and unresolved sources as a function of wavelength
Y1  - 2020
VL  - 494
IS  - 4
PB  - Wiley-Blackwell
CY  - Oxford
ER  - 
TY  - GEN
A1  - Abdalla, Hassan E.
A1  - Adam, Remi
A1  - Aharonian, Felix A.
A1  - Benkhali, Faical Ait
A1  - Angüner, Ekrem Oǧuzhan
A1  - Arakawa, Masanori
A1  - Arcaro, C
A1  - Armand, Catherine
A1  - Armstrong, T.
A1  - Egberts, Kathrin
T1  - Very high energy γ-ray emission from two blazars of unknown redshift and upper limits on their distance
T2  - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - We report on the detection of very high energy (VHE; E > 100 GeV) gamma-ray emission from the BL Lac objects KUV 00311-1938 and PKS 1440-389 with the High Energy Stereoscopic System (H.E.S.S.). H.E.S.S. observations were accompanied or preceded by multiwavelength observations with Fermi/LAT, XRT and UVOT onboard the Swift satellite, and ATOM. Based on an extrapolation of the Fermi/LAT spectrum towards the VHE gamma-ray regime, we deduce a 95 per cent confidence level upper limit on the unknown redshift of KUV 00311-1938 of z < 0.98 and of PKS 1440-389 of z < 0.53. When combined with previous spectroscopy results, the redshift of KUV 00311-1938 is constrained to 0.51 <= z < 0.98 and of PKS 1440-389 to 0.14 (sic) z < 0.53.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1202 
KW  - BL Lacertae objects: individual
KW  - galaxies: high-redshift
KW  - gamma-rays: general
KW  - Resolved and unresolved sources as a function of wavelength
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-526000
SN  - 1866-8372
IS  - 4
ER  -