14.2k citations
Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- Goddard Space Flight CenterUS361 papers
- Marshall Space Flight CenterUS357 papers
- Centre National de la Recherche ScientifiqueFR280 papers
- Max Planck Institute for Extraterrestrial PhysicsDE240 papers
- University of Maryland, College ParkUS239 papers
- Universities Space Research AssociationUS214 papers
- Stanford UniversityUS212 papers
- National Institute for AstrophysicsIT196 papers
- University of Rome Tor VergataIT184 papers
- Commissariat à l'Énergie Atomique et aux Énergies AlternativesFR179 papers
- University of PaduaIT178 papers
- Istituto Nazionale di Fisica Nucleare, Roma Tor VergataIT175 papers
21 papers · 2 filters
Chandra Observations of the Anomalous X-ray Pulsar 4U 0142+61
Sandeep K. Patel, Chryssa Kouveliotou, Peter M. Woods +7
We present X-ray imaging, timing, and phase resolved spectroscopy of the anomalous X-ray pulsar 4U 0142+61 using the Chandra X-ray Observatory. The spectrum is well described by a…
Distance Determination of Variable Galactic Sources
J. Hu, S. N. Zhang, T. P. Li
We have developed a timing analysis method to determine the distances of variable galactic X-ray sources based on the method advanced by Trümper and Schönfelder in 1973. The light-…
Relativistic Effects on the Appearance of a Clothed Black Hole
Xiaoling Zhang, S. Nan Zhang, Yuxin Feng +1
For an accretion disk around a black hole, the strong relativistic effects affect every aspect of the radiation from the disk, including its spectrum, light-curve, and image. This…
A massive warm baryonic halo in the Coma cluster
M. Bonamente, M. K. Joy, R. Lieu
Several deep PSPC observations of the Coma cluster reveal a very large-scale halo of soft X-ray emission, substantially in excess of the well known radiation from the hot intra-clu…
An accretion model for the growth of the central black hole associated with ionization instability in quasars
Y. Lu, K. S. Cheng, S. N. Zhang
A possible accretion model associated with the ionization instability of quasar disks is proposed to address the growth of the central black hole harbored in the host galaxy.The ma…
The Properties of Microjansky Radio Sources in the HDF-N, SSA13, and SSA22 Fields
S. C. Chapman, A. J. Barger, L. L. Cowie +9
(abridged) We present multiwavelength observations for a large sample of microjansky radio sources detected in ultradeep 1.4GHz maps centered on the Hubble Deep Field-North (HDF-N)…
XMM-Newton confirmation of Soft X-ray excess emission in clusters of galaxies - the discovery of O VII emission from an extended warm baryonic component
J. S. Kaastra, R. Lieu, T. Tamura +2
We investigate a sample of 14 clusters of galaxies observed with XMM-Newton in a search for soft X-ray excess emission. In five of these clusters a significant soft excess is evide…
The Faint Sky Variability Survey I: Goals and data reduction process
Paul J. Groot, Paul M. Vreeswijk, Mark E. Huber
The Faint Sky Variability Survey is aimed at finding photometric and/or astrometric variable objects in the brightness range between 16<V<24 on timescales between tens of minutes a…
Soft X-ray excess emission in clusters of galaxies observed with XMM-Newton
J. Nevalainen, R. Lieu, M. Bonamente +1
We present results on the spectroscopic analysis of XMM-Newton EPIC data of the central 0.5/h_50 Mpc regions of the clusters of galaxies Coma, A1795 and A3112. The temperature of t…
RHESSI as a Hard X-Ray Polarimeter
M. L. McConnell, J. M. Ryan, D. M. Smith +2
Polarization measurements of hard X-rays from solar flares can provide a direct handle on the extent to which the accelerated electrons are beamed, which, in turn, has important im…
How Sample Completeness Affects Gamma-Ray Burst Classification
Jon Hakkila, Timothy W. Giblin, Richard J. Roiger +3
Unsupervised pattern recognition algorithms support the existence of three gamma-ray burst classes; Class I (long, large fluence bursts of intermediate spectral hardness), Class II…
A Chandra Spectroscopic Survey of Persistent Black Hole Candidates
W. Cui, Y. X. Feng, S. N. Zhang +3
We present results from observations of persistent black hole candidates with the High Energy Transmission Gratings aboard the Chandra X-ray Observatory. The sources include LMC X-…
Low-energy X-ray emission from the Abell 2199 cluster of galaxies
Jelle S. Kaastra, Richard Lieu, Johan A. M. Bleeker +2
In a recent Letter, Berghoefer & Bowyer rediscussed the analysis of BeppoSAX LECS data of the cluster of galaxies Abell 2199 as presented by Kaastra et al., in particular the detec…
A Comprehensive Study of Pulse Profile Evolution in SGR 1806-20 & SGR 1900+14 with the RXTE PCA
Ersin Gogus, Chryssa Kouveliotou, Peter M. Woods +2
Soft Gamma Repeaters undergo pulse profile changes in connection with their burst activity. Here we present a comprehensive pulse profile history of SGR 1806-20 and SGR 1900+14 in…
The soft X-ray emission in a large sample of galaxy clusters with ROSAT PSPC
M. Bonamente, R. Lieu, M. K. Joy +1
The study of soft X-ray emission of 38 X-ray selected galaxy clusters observed by ROSAT PSPC indicates that the soft excess phenomenon may be a common occurrence in galaxy clusters…
The extreme ultraviolet excess emission in five clusters of galaxies revisited
Florence Durret, Eric Slezak, Richard Lieu +2
Evidence for excess extreme ultraviolet (EUV) emission over a tail of X-ray gas bremsstrahlung emission has been building up recently, but in some cases remains controversial, most…
XMM-Newton observation of the distant (z=0.6) galaxy cluster RX J1120.1+4318
M. Arnaud, S. Majerowicz, D. Lumb +12
We report on a 20 ksec XMM observation of the distant cluster RXJ1120.1+4318, discovered at z=0.6 in the SHARC survey. The cluster has a regular spherical morphology, suggesting it…
Understanding the long-term spectral variability of Cygnus X-1 with BATSE and ASM observations
Andrzej A. Zdziarski, Juri Poutanen, William S. Paciesas +1
We present an analysis of all observations of Cygnus X-1 by the BATSE (20-300 keV) and by ASM (1.5-12 keV) until 2002 June, including 1200 days of simultaneous data. We find a numb…
The effect of Planck scale space time fluctuations on Lorentz invariance at extreme speeds
Richard Lieu
The starting point of this work is the axiomatic existence of a smallest measurable interval, viz. the Planck time , set by quantum fluctuations in the vacuum metric tensor. B…
Extended Power-Law Decays in BATSE Gamma-Ray Bursts: Signatures of External Shocks?
T. W. Giblin, V. Connaughton, J. van Paradijs +5
The connection between Gamma-Ray Bursts (GRBs) and their afterglows is currently not well understood. Afterglow models of synchrotron emission generated by external shocks in the G…
The Micro-Jansky Sky at 8.4 GHz
E. B. Fomalont, K. I. Kellermann, R. B. Partridge +2
We present the results from two radio integrations at 8.4 GHz using the VLA. One of the fields, at 13h,+43d (SA13 field), has an rms noise level of 1.49 microJy and is the deepest…