Now showing items 1-20 of 72

• #### The 2010 very high energy γ-ray flare and 10 years of multi-wavelength observations of M 87 ﻿

(IOP Publishing, 2012)
The giant radio galaxy M 87 with its proximity (16 Mpc), famous jet, and very massive black hole ((3 – 6) × 109 M☉) provides a unique opportunity to investigate the origin of very high energy (VHE; E > 100 GeV) γ-ray ...
• #### Accelerating high-energy pulsar radiation codes ﻿

(IOP Publishing, 2010)
Curvature radiation (CR) is believed to be a dominant mechanism for creating gamma-ray emission from pulsars and is emitted by relativistic particles that are constrained to move along curved magnetic field lines. Additionally, ...
• #### Constraining a general-relativistic frame-dragging model for pulsed radiation from a population of millisecond pulsars in 47 Tucanae using GLAST LAT ﻿

(IOP Publications, 2008)
Although only 22 millisecond pulsars (MSPs) are currently known to exist in the globular cluster (GC) 47 Tucanae, this cluster may harbor 30-60 MSPs, or even up to ∼200. In this Letter, we model the pulsed curvature radiation ...
• #### Constraints on injection parameters of cosmic rays in the Galactic center from resolved HESS observations ﻿

(Elsevier Ltd., 2008)
• #### Constraints on the multi-TeV particle population in the Coma galaxy cluster with HESS observations ﻿

(EDP Sciences, 2009)
• #### Contributions from nearby pulsars to the local cosmic ray electron spectrum ﻿

(Elsevier, 2008)
PSR J0437-4715 is one of the closest millisecond pulsars (MSPs) to Earth, lying at a distance of _140 pc. This pulsar has a characteristic age of 4.9 Gyr and a relatively low spindown power of _1034 ergs/s. During its ...
• #### Contributions from nearby pulsars to the local cosmic ray electron spectrum ﻿

(Elsevier, 2008)
PSR J0437-4715 is one of the closest millisecond pulsars (MSPs) to Earth, lying at a distance of ∼140 pc. This pulsar has a characteristic age of 4.9 Gyr and a relatively low spindown power of ∼1034 ergs/s. During its ...
• #### A cosmic-ray positron anisotropy due to two middle-aged, nearby pulsars? ﻿

(IOP Publishing, 2008)
Geminga and B0656+14 are the closest pulsars with characteristic ages in the range of 100 kyr to 1 Myr. They both have spin-down powers of the order 3 × 1034 ergs s–1 at present. The winds of these pulsars had most probably ...
• #### Detection of gamma rays from a starburst galaxy ﻿

(AAAS, 2009)
Starburst galaxies exhibit in their central regions a highly increased rate of supernovae, the remnants of which are thought to accelerate energetic cosmic rays up to energies of ~1015 electron volts. We report the detection ...
• #### Detection of very high energy radiation from HESS J1908+063 confirms the Milagro unidentified source MGRO J1908+06 ﻿

(EDP Sciences, 2009)
Aims. Detection of a $\gamma$-ray source above 300 GeV is reported, confirming the unidentified source MGRO J1908+06, discovered by the Milagro collaboration at a median energy of 20 TeV. Methods. The source was observed ...
• #### Detection of very-high-energy y-ray emission from the vicinity of PSR B1706-44 and G 343.1-2.3 with H.E.S.S.  ﻿

(EDP Sciences, 2011)
The γ-ray pulsar PSRB1706−44 and the adjacent supernova remnant (SNR) candidate G343.1−2.3 were observed by H.E.S.S. during a dedicated observation campaign in 2007. As a result of this observation campaign, a new source ...
• #### Discovery and follow-up studies of the extended, off-plane, VHE gamma-ray source HESS J1507-622 ﻿

(EDP Sciences, 2011)
Context. The detection of gamma-rays in the very-high-energy (VHE) range (100 GeV−100 TeV) offers the possibility of studying the parent population of ultrarelativistic particles found in astrophysical sources, so it is ...
• #### Discovery of a VHE gamma-ray source coincident with the supernova remnant CTB 37A ﻿

(EDP Sciences, 2008)
Aims. The supernova remnant (SNR) complex CTB 37 is an interesting candidate for observations with very high energy (VHE) γ-ray telescopes such as HESS. In this region, three SNRs are seen. One of them is potentially ...
• #### Discovery of extended VHE Y-ray emission from the vicinity of the young massive stellar cluster Westerlund 1 ﻿

(EDP Sciences, 2012)
Aims. Results obtained in very-high-energy (VHE; E≥100GeV) γ-ray observations performed with the H.E.S.S. telescope array are used to investigate particle acceleration processes in the vicinity of the young massive stellar ...
• #### Discovery of gamma-ray emission from the extragalactic pulsar wind nebula N 157B with H.E.S.S ﻿

(EDP Sciences, 2012)
We present the significant detection of the first extragalactic pulsar wind nebula (PWN) detected in gamma rays, N 157B, located in the large Magellanic Cloud (LMC). Pulsars with high spin-down luminosity are found to power ...
• #### Discovery of gamma-ray emission from the shell-type supernova remnant RCW 86 with HESS ﻿

(IOP Publishing, 2009)
The shell-type supernova remnant (SNR) RCW 86, possibly associated with the historical supernova SN 185, with its relatively large size (about 40' in diameter) and the presence of nonthermal X-rays is a promising target ...
• #### Discovery of hard-spectrum y-ray emission from the BL Lacertae object 1ES0414+009 ﻿

(EDP Sciences, 2012)
Context. 1ES 0414 + 009 (z = 0.287) is a distant high-frequency-peaked BL Lac object, and has long been considered a likely emitter of very-high-energy (VHE, E > 100 GeV) γ-rays due to its high X-ray and radio flux. Aims. ...
• #### Discovery of the source HESS J1356-645 associated with the young and energetic PSR J1357-6429 ﻿

(EDP Sciences, 2011)
Context. Several newly discovered very-high-energy (VHE; E > 100 GeV) γ-ray sources in the Galaxy are thought to be associated with energetic pulsars. Among them, middle-aged (≳104 yr) systems exhibit large centre-filled ...
• #### Discovery of very high energy gamma-ray emission coincident with molecular clouds in the W 28 (G6.4-0.1) field ﻿

(EDP Sciences, 2008)
Aims. Observations of shell-type supernova remnants (SNRs) in the GeV to multi-TeV γ-ray band, coupled with those at millimetre radio wavelengths, are motivated by the search for cosmic-ray accelerators in our Galaxy. The ...
• #### Discovery of very high energy y-ray emission from Centaurus A with HESS. ﻿

(IOP Publishing, 2009)
We report the discovery of faint very high energy (VHE; E > 100 GeV) γ-ray emission from the radio galaxy Centaurus A in observations performed with the High Energy Stereoscopic System (H.E.S.S.) experiment, an imaging ...

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