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We present the results from a multiwavelength campaign conducted in 2006 August of the powerful -ray quasar PKS 1510À089 (z ¼ 0:361). This campaign commenced with a deep Suzaku observation lasting 3 days for a total exposure time of 120 ks and continued with Swift monitoring over 18 days. Besides Swift observations, the campaign included ground-based optical and radio data and yielded a quasi-simultaneous broadband spectrum from 10 9 to 10 19 Hz. The Suzaku observation provided a high signal-to-noise ratio X-ray spectrum, which is well represented by an extremely hard power law with a photon index of À ' 1:2, augmented by a soft component apparent below 1 keV, which is well described by a blackbody model with a temperature of kT ' 0:2 keV. Monitoring by Suzaku revealed temporal variability that differs between the low-and high-energy bands, again suggesting the presence of a second, variable component in addition to the primary power-law emission. We model the broadband spectrum, assuming that the high-energy spectral component results from Comptonization of infrared radiation produced by hot dust located in the surrounding molecular torus. The adopted internal shock scenario implies that the power of the jet is dominated by protons, but with a number of electrons and/or positrons that exceeds the number of protons by a factor of $10. We also find that inhomogeneities responsible for the shock formation prior to the collision may produce bulk Compton radiation, which can explain the observed soft X-ray excess and possible excess at $18 keV. We note, however, that the bulk Compton interpretation is not unique, as discussed briefly in the text.

High-resolution X-ray spectroscopy with Hitomi was expected to resolve the origin of the faint unidentified » E 3.5 keV emission line reported in several low-resolution studies of various massive systems, such as galaxies and clusters, including the Perseus cluster. We have analyzed the Hitomi first-light observation of the Perseus cluster. The emission line expected for Perseus based on the XMM-Newton signal from the large cluster sample under the dark matter decay scenario is too faint to be detectable in the Hitomi data. However, the previously reported 3.5 keV flux from Perseus was anomalously high compared to the sample-based prediction. We find no unidentified line at the reported high flux level. Taking into account the XMM measurement uncertainties for this region, the inconsistency with Hitomi is at a 99% significance for a broad dark matter line and at 99.7% for a narrow line from the gas. We do not find anomalously high fluxes of the nearby faint K line or the Ar satellite line that were proposed as explanations for the earlier 3.5 keV detections. We do find a hint of a broad excess near the energies of high-n transitions of S XVI (  E 3.44 keV rest-frame)-a possible signature of charge exchange in the molecular nebula and another proposed explanation for the unidentified line. While its energy is consistent with XMM pn detections, it is unlikely to explain the MOS signal. A confirmation of this interesting feature has to wait for a more sensitive observation with a future calorimeter experiment.

We present the results from the Chandra ACIS CC mode observation of an anomalous X-ray pulsar (AXP) 1E 1841-045. This is the first observation in which the pulsar spectrum in wide energy range is spatially discriminated from the surrounding SNR, Kes 73. Like other AXPs, the phase-integrated spectrum is fitted well with power-law plus blackbody model. The spectral parameters are Γ = 2.0 ± 0.3, kT BB = 0.44 ± 0.02 keV, and N H = 2.54 +0.15 −0.13 × 10 22 cm −2 . This photon index is significantly flatter than the other AXPs, and resemble to soft gamma-ray repeaters (SGRs) in the quiescent state. The pulse profile is double-peaked, and we found that the second peak has significantly hard spectrum. The spectra of all phases are consistent with power-law plus blackbody model with constant temperature and photon index. When fitted with two blackbody model, we obtained similarly good fit. These results can be interpreted that there are two emission regions with different energy spectra.