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The magnificent seven: magnetic fields and surface temperature distributions
Haberl, Frank
Presently seven nearby radio-quiet isolated neutron stars discovered in ROSAT data and characterized by thermal X-ray spectra are known. They exhibit very similar properties and despite intensive searches their number remained constant since 2001 which led to their name "The Magnificent Seven". Five of the stars exhibit pulsations in their X-ray f…
X-ray observations of ultraluminous X-ray sources
Roberts, Timothy P.
Ultraluminous X-ray sources (ULXs) are amongst the most intriguing of X-ray source classes. Their extreme luminosities—greater than 1039 erg s‑1 in the 0.3–10 keV band alone—suggest either the presence of black holes larger than those regularly encountered in our own Galaxy (the Galactic centre excepted), or sources apparentl…
The anatomy of a magnetar: XMM monitoring of the transient anomalous X-ray pulsar XTE J1810–197
Gotthelf, E. V.; Halpern, J. P.
We present the latest results from a multi-epoch timing and spectral study of the Transient Anomalous X-ray Pulsar XTE J1810–197. We have acquired seven observations of this pulsar with the Newton X-ray Multi-mirror Mission (XMM-Newton) over the course of two and a half years, to follow the spectral evolution as the source fades from outburst. The…
The Magnificent Seven in the dusty prairie: The role of interstellar absorption on the observed neutron star population
Haberl, F.; Neuhäuser, R.; Turolla, R. +3 more
The Magnificent Seven have all been discovered by their exceptional soft X-ray spectra and high ratios of X-ray to optical flux. They all are considered to be nearby sources. Searching for similar objects with larger distances, one expects larger interstellar absorption resulting in harder X-ray counterparts. Current interstellar absorption treatm…
The complex X-ray spectrum of the isolated neutron star RBS1223
Haberl, Frank; Schwope, Axel D.; Motch, Christian +1 more
We present a first analysis of a deep X-ray spectrum of the isolated neutron star RBS1223 obtained with XMM-Newton. Spectral data from four new monitoring observations in 2005/2006 were combined with archival observations obtained in 2003 and 2004 to form a spin-phase averaged spectrum containing 290 000 EPIC-pn photons. This spectrum shows higher…
X-ray intensity-hardness correlation and deep IR observations of the anomalous X-ray pulsar 1RXS J170849-400910
Campana, S.; Stella, L.; Rea, N. +6 more
We report here on X-ray and IR observations of the Anomalous X-ray Pulsar (AXP) 1RXS J170849-400910. First, we report on new XMM-Newton, Swift-XRT and Chandra observations of this AXP, which confirm the intensity–hardness correlation observed in the long term X-ray monitoring of this source. These new X-ray observations show that the AXP flux is r…
XMM–Newton observations of soft gamma-ray repeaters
Mereghetti, Sandro; Esposito, Paolo; Tiengo, Andrea
All the confirmed Soft Gamma-ray Repeaters have been observed with the EPIC instrument on the XMM–Newton satellite. We review the results obtained in these observations, providing the most accurate spectra on the persistent X-ray emission in the 1–10 keV range for these objects, and discuss them in the context of the magnetar interpretation.
Our distorted view of magnetars: application of the resonant cyclotron scattering model
Turolla, Roberto; Rea, Nanda; Lyutikov, Maxim +1 more
The X-ray spectra of the magnetar candidates are customarily fitted with an empirical, two component model: an absorbed blackbody and a power-law. However, the physical interpretation of these two spectral components is rarely discussed. It has been recently proposed that the presence of a hot plasma in the magnetosphere of highly magnetized neutr…
Status of identification of VHE γ-ray sources
Funk, Stefan
With the recent advances made by Cherenkov telescopes such as H.E.S.S. the field of very high-energy (VHE) γ-ray astronomy has recently entered a new era in which for the first time populations of Galactic sources such as e.g. Pulsar wind nebulae (PWNe) or Supernova remnants (SNRs) can be studied. However, while some of the new sources can be asso…
Evidence for a binary companion to the central compact object 1E 1207.4-5209
Pavlov, George G.; Zavlin, Vyacheslav E.; Woods, Peter M.
Unique among neutron stars, 1E 1207.4-5209 is an X-ray pulsar with a spin period of 424 ms that contains at least two strong absorption features in its energy spectrum. This neutron star is positionally coincident with the supernova remnant PKS 1209-51/52 and has been identified as a member of the growing class of radio-quiet compact central objec…