Search Publications
The Fast UV Variability of the Active Galactic Nucleus in Fairall 9
Reynolds, Christopher S.; Mushotzky, Richard F.; Lohfink, Anne M. +2 more
We present the results from a new optical/UV/X-ray monitoring campaign of the luminous Seyfert galaxy Fairall 9 using the Swift satellite. Using the UV-Optical Telescope on Swift, we find correlated optical/UV variability on all timescales ranging from the sampling time (4 days) to the length of the campaign (2.5 months). In one noteworthy event, …
Constraining the True Nature of an Exotic Binary in the Core of NGC 6624
Pallanca, Cristina; Dalessandro, Emanuele; Ferraro, Francesco R. +4 more
We report on the identification of the optical counterpart to Star1, the exotic object serendipitously discovered by Deutsch et al. in the core of the Galactic globular cluster NGC 6624. Star1 has been classified by Deutsch et al. as either a quiescent cataclysmic variable or a low-mass X-ray binary. Deutsch et al. proposed StarA as a possible opt…
The Discovery of a Radio Halo in PLCK G147.3-16.6 at z = 0.65
van Weeren, R. J.; Forman, W. R.; Röttgering, H. J. A. +9 more
Recent X-ray and Sunyaev-Zel'dovich (SZ) observations have dramatically increased the number of known distant galaxy clusters. In some merging, low-redshift (z < 0.4) clusters, centrally located, diffuse, extended radio emission (radio halos) has been found. Using the Giant Metrewave Radio Telescope (GMRT), we report the detection of diffuse ra…
Tracking the Complex Absorption in NGC 2110 with Two Suzaku Observations
Okajima, Takashi; Fukazawa, Yasushi; Ueda, Yoshihiro +6 more
We present spectral analysis of two Suzaku observations of the Seyfert 2 galaxy, NGC 2110. This source has been known to show complex, variable absorption which we study in depth by analyzing these two observations set 7 yr apart and by comparing them to previously analyzed observations with the XMM-Newton and Chandra observatories. We find that t…
The Norma Arm Region Chandra Survey Catalog: X-Ray Populations in the Spiral Arms
An, Hongjun; Bauer, Franz E.; Stern, Daniel +6 more
We present a catalog of 1415 X-ray sources identified in the Norma Arm Region Chandra Survey (NARCS), which covers a 2° × 0.°8 region in the direction of the Norma spiral arm to a depth of ≈20 ks. Of these sources, 1130 are point-like sources detected with >=3σ confidence in at least one of three energy bands (0.5-10, 0.5-2, and 2-10 keV), five…
Measurements of Coronal Faraday Rotation at 4.6 R ⊙
Kooi, Jason E.; Fischer, Patrick D.; Buffo, Jacob J. +1 more
Many competing models for the coronal heating and acceleration mechanisms of the high-speed solar wind depend on the solar magnetic field and plasma structure in the corona within heliocentric distances of 5 R ⊙. We report on sensitive Very Large Array (VLA) full-polarization observations made in 2011 August, at 5.0 and 6.1 GHz (each wi…
Discovery of X-Ray Pulsations from the Next Geminga, PSR J1836+5925
Takata, J.; Kong, A. K. H.; Hui, C. Y. +5 more
We report recent XMM-Newton investigations of PSR J1836+5925, the "next Geminga," which determined an X-ray pulsation of ~173.3 ms. Its X-ray periodicity is consistent with the γ-ray ephemeris at the same epoch. The X-ray folded light curve has a sinusoidal structure that is different from the double-peaked γ-ray pulse profile. We have also analyz…
Discovery of X-Ray Pulsations from the INTEGRAL Source IGR J11014-6103
Camilo, F.; Chaty, S.; Rahoui, F. +6 more
We report the discovery of PSR J1101-6101, a 62.8 ms pulsar in IGR J11014-6103, a hard X-ray source with a jet and a cometary tail that strongly suggests it is moving away from the center of the supernova remnant (SNR) MSH 11-61A at v > 1000 km s-1. Two XMM-Newton observations were obtained with the EPIC pn in small window mode, resu…
On the Interaction of the PKS B1358-113 Radio Galaxy with the A1836 Cluster
Simionescu, A.; Cheung, C. C.; Stawarz, Ł. +9 more
Here we present the analysis of multifrequency data gathered for the Fanaroff-Riley type-II (FR II) radio galaxy PKS B1358-113, hosted in the brightest cluster galaxy in the center of A1836. The galaxy harbors one of the most massive black holes known to date, and our analysis of the acquired optical data reveals that this black hole is only weakl…
Intermediate-age Globular Clusters in Four Galaxy Merger Remnants
Schweizer, François; Miller, Bryan W.; Trancho, Gelys +2 more
We present the results of combining Hubble Space Telescope optical photometry with ground-based Ks -band photometry from the Gemini imagers NIRI and FLAMINGOS-I to study the globular cluster (GC) populations in four early-type galaxies that are candidate remnants of recent mergers (NGC 1700, NGC 2865, NGC 4382, and NGC 7727). These gala…