Search Publications
TANAMI blazars in the IceCube PeV-neutrino fields
Gehrels, N.; Thompson, D. J.; Wilms, J. +39 more
The IceCube Collaboration has announced the discovery of a neutrino flux in excess of the atmospheric background. Owing to the steeply falling atmospheric background spectrum, events at PeV energies most likely have an extraterrestrial origin. We present the multiwavelength properties of the six radio-brightest blazars that are positionally coinci…
The 100-month Swift catalogue of supergiant fast X-ray transients. I. BAT on-board and transient monitor flares
Gehrels, N.; Esposito, P.; Ducci, L. +10 more
Context. Supergiant fast X-ray transients (SFXTs) are high mass X-ray binaries (HMXBs) that are defined by their hard X-ray flaring behaviour. During these flares they reach peak luminosities of 1036-1037 erg s-1 for a few hours (in the hard X-ray), which are much shorter timescales than those characterizing Be/X-r…
Long-term change in the cyclotron line energy in Hercules X-1
Harrison, F. A.; Klochkov, D.; Wilms, J. +5 more
Aims: We investigate the long-term evolution of the cyclotron resonance scattering feature (CRSF) in the spectrum of the binary X-ray pulsar
Metho…
Monte Carlo modelling of the propagation and annihilation of nucleosynthesis positrons in the Galaxy
Jean, P.; Ferrière, K.; Alexis, A. +1 more
Aims: We want to estimate whether the positrons produced by the β+-decay of 26Al, 44Ti, and 56Ni synthesised in massive stars and supernovae are sufficient to explain the 511 keV annihilation emission observed in our Galaxy. Such a possibility has often been put forward in the past. In a previous st…
Coronal origin of the polarization of the high-energy emission of Cygnus X-1
Chaty, S.; Romero, G. E.; Vieyro, F. L.
Context. Cygnus X-1 is the candidate with the highest probability of containing a black hole among the X-ray binary systems in the Galaxy. It is also by far the most often studied of these objects. Recently, the International Gamma-Ray Astrophysics Laboratory Imager on board the Integral satellite (INTEGRAL/IBIS) detected strong polarization in th…
PKS 1510-089: a rare example of a flat spectrum radio quasar with a very high-energy emission
Barnacka, Anna; Moderski, Rafal; Behera, Bagmeet +2 more
Context. The blazar
GRB 120711A: an intense INTEGRAL burst with long-lasting soft γ-ray emission and a powerful optical flash
Covino, S.; Fugazza, D.; Greiner, J. +20 more
A long and intense γ-ray burst (GRB) was detected by INTEGRAL on 11 July 2012 with a duration of ~115 s and fluence of 2.8 × 10-4 erg cm-2 in the 20 keV-8 MeV energy range. GRB 120711A was at z ~ 1.405 and produced soft γ-ray emission (>20 keV) for at least ~10 ks after the trigger. The GRB was observed by several ground-b…
GROND coverage of the main peak of gamma-ray burst 130925A
van Eerten, H.; Greiner, J.; Hurley, K. +23 more
Aims: Prompt or early optical emission in gamma-ray bursts (GRBs) is notoriously difficult to measure, and observations of the dozen cases show a large variety of properties. Yet, such early emission promises to help us achieve a better understanding of the GRB emission process(es).
Methods: We performed dedicated observations of the ult…
The spectral catalogue of INTEGRAL gamma-ray bursts. results of the joint IBIS/SPI spectral analysis
Götz, D.; Bošnjak, Ž.; Bouchet, L. +2 more
We present the updated INTEGRAL catalogue of gamma-ray bursts (GRBs) observed between December 2002 and February 2012. The catalogue contains the spectral parameters for 59 GRBs localized by the INTEGRAL Burst Alert System (IBAS). We used the data from the two main instruments on board the INTEGRAL satellite: the spectrometer SPI (SPectrometer on …
Multiwavelength campaign on Mrk 509. XIII. Testing ionized-reflection models on Mrk 509
Kaastra, J. S.; Kriss, G. A.; Arav, N. +12 more
Active galactic nuclei (AGN) are the most luminous persistent objects in the universe. The X-ray domain is particularly important because the X-ray flux represents a significant fraction of the bolometric emission from such objects and probes the innermost regions of accretion disks, where most of this power is generated. An excess of X-ray emissi…