Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- Centre National de la Recherche ScientifiqueFR1.6k papers
- Institut National de Physique Nucléaire et de Physique des ParticulesFR1.4k papers
- Heidelberg UniversityDE1.3k papers
- Max Planck SocietyDE1.1k papers
- University of ZurichCH1.1k papers
- European Organization for Nuclear ResearchCH1k papers
- Laboratoire de Physique Nucléaire et de Hautes ÉnergiesFR990 papers
- Institute of Nuclear Physics, Polish Academy of SciencesPL973 papers
- University of Maryland, College ParkUS940 papers
- Rutherford Appleton LaboratoryGB939 papers
- Institute for Nuclear ResearchRU922 papers
- Istituto Nazionale di Fisica Nucleare, Sezione di BolognaIT912 papers
39 papers · 2 filters
Search for a TeV gamma-ray halo of Mkn 501
HEGRA Collaboration, F. Aharonian
For distant extragalactic sources of gamma-rays in the PeV energy range, interactions of the gamma rays with intergalactic diffuse radiation fields will initiate a pair cascade. De…
Gamma Rays from Molecular Clouds
F. A. Aharonian
I discuss the spectral features of pi-0 decay gamma-radiation from clouds/targets located in proximity of relatively young proton accelerators, and speculate that such ``accelerato…
Cosmic Dust: The Ulysses perspective
Eberhard Grün, Harald Krüger, Markus Landgraf
The Ulysses spacecraft, launched in October 1990, orbits the Sun on a polar trajectory. The spacecraft is equipped with a highly sensitive impact- ionization dust detector which ca…
Reanalysis of the high energy cutoff of the 1997 Mkn 501 TeV energy spectrum
HEGRA Collaboration, F. Aharonian
Data taken with the HEGRA system of imaging atmospheric Cherenkov telescopes during the 1997 flares of Mkn 501 are reanalyzed using an algorithm providing improved energy resolutio…
Stereo Imaging of the VHE Gamma-Rays with HEGRA and H.E.S.S
Alexander K Konopelko
At present, the ground-based astronomy of very high energy (VHE) (E>100 GeV) gamma-rays experiences the challenging transition phase caused by the substantial upgrading of its obse…
Reconnection in a striped pulsar wind
Y. Lyubarsky, J. G. Kirk
It is generally thought that most of the spin-down power of a pulsar is carried away in an MHD wind dominated by Poynting flux. In the case of an oblique rotator, a significant par…
Broad-band diffuse gamma ray emission of the Galactic Disk
F. A. Aharonian, A. M. Atoyan
The contributions of different radiation mechanisms to the diffuse gamma-ray emission of the galactic disk are studied in a broad energy region from X-rays to very high energy gamm…
Complex Spectral Variability from Intensive Multi-wavelength Monitoring of Mrk421 in 1998
T. Takahashi, J. Kataoka, G. Madejski +20
We conducted a multi-frequency campaign for the TeV blazar Mrk~421 in 1998 April. The campaign started from a pronounced high amplitude flare recorded by SAX and Whipple; ASCA obse…
Blue Quasars and Blazar Unification Schemes
Markos Georganopoulos
Blue quasars (BQs) are sources with strong broad emission lines and flat hard X-ray spectra, properties that resemble classical flat spectrum radio quasars (FSRQs), and high peak f…
First Results from the Heidelberg Dark Matter Search Experiment
L. Baudis, A. Dietz, B. Majorovits +3
The Heidelberg Dark Matter Search Experiment (HDMS) is a new ionization Germanium experiment in a special design. Two concentric Ge crystals are housed by one cryostat system, the…
Neutron Stars and Quantum Billiards
Aurel Bulgac, Piotr Magierski
Homogeneous neutron matter at subnuclear densities becomes unstable towards the formation of inhomogeneities. Depending on the average value of the neutron density one can observe…
The TeV Energy Spectrum of Mkn 501 Measured with the Stereoscopic Telescope System of HEGRA during 1998 and 1999
The HEGRA Collaboration, F. Aharonian, A. Akhperjanian +1
During 1997, the BL Lac object Mkn 501 went into an extraordinary state of high X-ray and TeV gamma-ray activity, lasting more than 6 months. In this paper we report on the TeV emi…
Modelling the spectral energy distribution of galaxies. I. Radiation fields and grain heating in the edge-on spiral NGC891
Cristina C. Popescu, Angelos Misiriotis, Nikolaos D. Kylafis +2
We describe a new tool for the analysis of the UV to the sub-millimeter (sub-mm) spectral energy distribution (SED) of spiral galaxies. We use a consistent treatment of grain heati…
1.65 micron (H-band) surface photometry of galaxies. V: Profile decomposition of 1157 galaxies
G. Gavazzi, P. Franzetti, M. Scodeggio +2
We present near-infrared H-band (1.65 micron) surface brightness profile decomposition for 1157 galaxies in five nearby clusters of galaxies: Coma, A1367, Virgo, A262 and Cancer, a…
Optimizing the angular resolution of the HEGRA telescope system to study the emission region of VHE gamma rays in the Crab Nebula
HEGRA Collaboration, F. Aharonian
The HEGRA system of imaging atmospheric Cherenkov telescopes provides for specially selected classes of events an angular resolution of better than 3'. By comparing the measured an…
A Dust Cloud of Ganymede Maintained by Hypervelocity Impacts of Interplanetary Micrometeoroids
Harald Krüger, Alexander V. Krivov, Eberhard Grün
A dust cloud of Ganymede has been detected by in-situ measurements with the dust detector onboard the Galileo spacecraft. The dust grains have been sensed at altitudes below five G…
5@5 - a 5 GeV energy threshold array of imaging atmospheric Cherenkov telescopes at 5 km altitude
F. A. Aharonian, A. K. Konopelko, H. J. Voelk +1
We discuss the concept and the performance of a powerful future ground-based astronomical instrument - a stereoscopic array of several large imaging atmospheric Cherenkov telescope…
Rejection of the hypothesis that Markarian 501 TeV photons are pure Bose-Einstein condensates
The HEGRA Collaboration, F. Aharonian, A. Akhperjanian +1
The energy spectrum of the Blazar type galaxy Markarian 501 (Mrk 501) as measured by the High-Energy-Gamma-Ray Astronomy (HEGRA) air Cerenkov telescopes extends beyond 16 TeV and c…
Hot and Cold Dark Matter Search with GENIUS
Laura Baudis, Alexander Dietz, Gerd Heusser +3
GENIUS is a proposal for a large volume detector to search for rare events. An array of 40-400 'naked' HPGe detectors will be operated in a tank filled with ultra-pure liquid nitro…
On the nonthermal X-ray emission in blazar jets
F. M. Rieger, J. G. Kirk, A. Mastichiadis
We consider particle acceleration to high energy via diffusive shock acceleration in a simple, self-consistent shock in jet model for blazars. Electrons are assumed to be accelerat…
Early Starbursts and Magnetic Field Generation in Galaxy Clusters
Heinrich J. Voelk, A. M. Atoyan
We propose a mechanism for the early generation of the mean Intracluster magnetic field in terms of magnetized galactic winds. These winds are the result of starburst phases of the…
Particle acceleration at ultrarelativistic shocks: an eigenfunction method
J. G. Kirk, A. W. Guthmann, Y. A. Gallant +1
We extend the eigenfunction method of computing the power-law spectrum of particles accelerated at a relativistic shock fronts to apply to shocks of arbitrarily high Lorentz factor…
Mapping IR Enhancements in Closely Interacting Spiral-Spiral Pairs. I. ISO~CAM and ISO~SWS Observations
Cong Xu, Yu Gao, Joseph Mazzarella +3
Mid-infrared (MIR) imaging and spectroscopic observations are presented for a well defined sample of eight closely interacting (CLO) pairs of spiral galaxies that have overlapping…
Constraints on the Cosmic Infra-Red Background based on BeppoSAX and CAT spectra of Mkn 501
J. Guy, C. Renault, F. A. Aharonian +2
The TeV and X-ray data obtained by the imaging Cherenkov telescope CAT and X-ray satellite BeppoSAX during the remarkable flare of Mkn 501 in April 16, 1997 are used to constrain t…