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Discovery of hard-spectrum y-ray emission from the BL Lacertae object 1ES 0414+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 VHE y-ray emission and multi-wavelength observations of the BL Lacertae object 1RXS J101015.9-311909
(EDP Science, 2012)
1RXS J101015.9 − 311909 is a galaxy located at a redshift of z = 0.14 hosting an active nucleus (called AGN) belonging to the class of bright BL Lac objects. Observations at high (HE, E > 100 MeV) and very high (VHE, E > ...
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 ...
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 ...
Multi-wavelength modeling of globular clusters: the millisecond pulsar scenario
(IOP Publishing, 2013)
The potentially large number of millisecond pulsars (MSPs) in globular cluster (GC) cores makes these parent objects ideal laboratories for studying the collective properties of an ensemble of MSPs. Such a population is ...
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 ...
HESS upper limit on the very high energy γ-ray emission from the globular cluster 47 Tucanae
(EDP Sciences, 2009)
Observations of the globular cluster 47 Tucanae (NGC 104), which contains at least 23 ms pulsars, were performed with the HESS telescope system. The observations lead to an upper limit of F(E > 800 GeV) < 6.7 × 10−13 cm−2 ...
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 ...
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 ...