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Swift Follow-up Observations of Candidate Gravitational-wave Transient Events
Liu, Y.; Lee, H. M.; Foley, S. +815 more
We present the first multi-wavelength follow-up observations of two candidate gravitational-wave (GW) transient events recorded by LIGO and Virgo in their 2009-2010 science run. The events were selected with low latency by the network of GW detectors (within less than 10 minutes) and their candidate sky locations were observed by the Swift observa…
A Remarkable Long-term Light Curve and Deep, Low-state Spectroscopy: Swift and XMM-Newton Monitoring of the NLS1 Galaxy Mkn 335
Fabian, Andrew C.; Komossa, S.; Gallo, Luigi C. +5 more
The narrow-line Seyfert 1 galaxy (NLS1) Mkn 335 is remarkable because it has repeatedly shown deep, long X-ray low states that show pronounced spectral structure. It has become one of the prototype active galactic nuclei (AGNs) in deep minimum X-ray states. Here we report on the continuation of our ongoing monitoring campaign with Swift and the ex…
An XMM-Newton Survey of the Soft X-Ray Background. II. An All-Sky Catalog of Diffuse O VII and O VIII Emission Intensities
Henley, David B.; Shelton, Robin L.
We present an all-sky catalog of diffuse O VII and O VIII line intensities, extracted from archival XMM-Newton observations. This catalog supersedes our previous catalog, which covered the sky between l = 120° and l = 240°. We attempted to reduce the contamination from near-Earth solar wind charge exchange (SWCX) emission by excluding times of hig…
The Deep Look at the Hard X-Ray Sky: The Swift-INTEGRAL X-Ray (SIX) Survey
Greiner, Jochen; Ajello, Marco; Bottacini, Eugenio
The supermassive black holes at the center of active galactic nuclei (AGNs) are surrounded by obscuring matter that can block nuclear radiation. Depending on the amount of blocked radiation, the flux from the AGN can be too faint to be detected by currently flying hard X-ray (above 15 keV) missions. At these energies only ~1% of the intensity of t…