338 citations · 1.9k across the 27 of their papers we have counts for
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Testing the inverse-Compton catastrophe scenario in the intra-day variable blazar S5 0716+71, III. Rapid and correlated flux density variability from radio to sub-mm bands
L. Fuhrmann, T. P. Krichbaum, A. Witzel +22
The BL Lac object S5 0716+71 was observed in a global multi-frequency campaign to search for rapid and correlated flux density variability and signatures of an inverse-Compton (IC)…
H.E.S.S. observations of the Galactic Center region and their possible dark matter interpretation
H. E. S. S. collaboration, :, F. A. Aharonian
The detection of gamma-rays from the source HESS J1745-290 in the Galactic Center (GC) region with the H.E.S.S. array of Cherenkov telescopes in 2004 is presented. After subtractio…
Absorption of Nuclear Gamma-rays on the Starlight Radiation in FR I Sources: the Case of Centaurus A
L. Stawarz, F. Aharonian, S. Wagner +1
Several BL Lac objects are confirmed sources of variable and strongly Doppler-boosted TeV emission produced in the nuclear portions of their relativistic jets. It is more than prob…
Testing the inverse-Compton catastrophe scenario in the intra-day variable blazar S5 0716+71. I. Simultaneous broadband observations during November 2003
L. Ostorero, S. J. Wagner, J. Gracia +6
Some intra-day variable, compact extra-galactic radio sources show brightness temperatures severely exceeding 10^{12} K, the limit set by catastrophic inverse-Compton (IC) cooling…
Discovery of very high energy gamma-rays associated with an X-ray binary
H. E. S. S. Collaboration, :, F. Aharonian
X-ray binaries are composed of a normal star in orbit around a neutron star or stellar-mass black hole. Radio and X-ray observations have led to the presumption that some X-ray bin…
Multi-wavelength observations of PKS 2155-304 with H.E.S.S
H. E. S. S. Collaboration, :, Aharonian
The High Energy Stereoscopic System (H.E.S.S.) has observed the high-frequency peaked BL Lac object PKS2155-304 in 2003 between October 19 and November 26 in Very High Energy (VHE)…
Observations of Mkn 421 in 2004 with H.E.S.S. at large zenith angles
H. E. S. S. Collaboration, :, F. Aharonian
Mkn 421 was observed during a high flux state for nine nights in April and May 2004 with the fully operational High Energy Stereoscopic System (H.E.S.S.) in Namibia. The observatio…
Serendipitous discovery of the unidentified extended TeV gamma-ray source HESS J1303-631
H. E. S. S. Collaboration, :, F. Aharonian
The serendipitous discovery of an unidentified extended TeVgamma-ray source close to the galactic plane named HESS J1303-631 at a significance of 21 standard deviations is reported…
Discovery of extended VHE gamma-ray emission from the asymmetric pulsar wind nebula in MSH 15-52 with H.E.S.S
H. E. S. S. Collaboration, :, F. Aharonian
The Supernova Remnant MSH 15-52 has been observed in very high energy (VHE) gamma-rays using the H.E.S.S. 4-telescope array located in Namibia. A gamma-ray signal is detected at th…
Upper limits to the SN1006 multi-TeV gamma-ray flux from H.E.S.S. observations
F. Aharonian
Observations of the shell-type supernova remnant SN1006 have been carried out with the H.E.S.S. system of Cherenkov telescopes during 2003 (18.2h with two operating telescopes) and…
Search for TeV emission from the region around PSR B1706-44 with the H.E.S.S. experiment
H. E. S. S. Collaboration, :, F. Aharonian
The region around PSR B1706-44 has been observed with the H.E.S.S. imaging atmospheric Cherenkov telescopes in 2003. No evidence for gamma-ray emission in the TeV range was found a…
Very high energy gamma rays from the composite SNR G0.9+0.1
H. E. S. S. Collaboration, :, F. Aharonian
Very high energy (> 100 GeV) gamma-ray emission has been detected for the first time from the composite supernova remnant G0.9+0.1 using the H.E.S.S. instrument. The source is dete…
H.E.S.S. Observations of PKS 2155-304
The H. E. S. S. Collaboration, :, F. Aharonian
The high-frequency peaked BL Lac PKS 2155-304 at redshift z=0.117 has been detected with high significance (~45 sigma) at energies greater than 160 GeV, using the H.E.S.S. stereosc…
Quasar Elemental Abundances at High Redshifts
M. Dietrich, F. Hamann, J. C. Shields +5
We examine rest-frame ultraviolet spectra of 70 high redshift quasars (z>3.5) to study the chemical enrichment history of the gas closely related to the quasars, and thereby estima…
High Redshift Quasars and Star Formation in the Early Universe
M. Dietrich, I. Appenzeller, M. Vestergaard +1
In order to derive information on the star formation history in the early universe we observed 6 high-redshift (z=3.4) quasars in the near-infrared to measure the relative iron and…
A search for broad infrared recombination lines in NGC 1068
D. Lutz, R. Genzel, E. Sturm +12
We report infrared spectroscopy of the prototypical Seyfert 2 galaxy NGC 1068, aiming at detection of broad components of hydrogen recombination lines that originate in the obscure…