Taking the Measure of the Universe : precision astrometry with SIM PlanetQuest (2008)
Unwin, Stephen C., Shao, Michael, Tanner, Angelle M., Allen, Ronald J., Beichman, Charles A., Boboltz, David, ...
Precision astrometry at microarcsecond accuracy has application to a wide range of astrophysical problems. This paper is a study of the science questions that can be addressed using an instrument...
Chandra Localizations and Spectra of INTEGRAL Sources in the Galactic Plane (2008)
Tomsick, John A., Chaty, Sylvain, Rodriguez, Jerome, Walter, Roland, Kaaret, Philip
We report on the results of observations of hard X-ray sources in the Galactic plane with the Chandra X-ray Observatory. The hard X-ray IGR sources were discovered by the INTEGRAL satellite, and the...
Tomsick, John A., Kalemci, Emrah, Kaaret, Philip, Markoff, Sera, Corbel, Stephane, Migliari, Simone, ...
A major question in the study of black hole binaries involves our understanding of the accretion geometry when the sources are in the hard state. In this state, the X-ray energy spectrum is dominated...
Chaty, Sylvain, Rahoui, Farid, Foellmi, Cédric, Tomsick, John A., Rodriguez, Jérôme, Walter, Roland
Context: The INTEGRAL hard X-ray observatory has revealed an emerging population of highly obscured X-ray binary systems through multi-wavelength observations. Previous studies have shown that many...
Taking the Measure of the Universe: Precision Astrometry with SIM PlanetQuest (2007)
Unwin, Stephen C., Shao, Michael, Tanner, Angelle M., Allen, Ronald J., Beichman, Charles A., Boboltz, David, ...
Precision astrometry at microarcsecond accuracy has application to a wide range of astrophysical problems. This paper is a study of the science questions that can be addressed using an instrument...
Tomsick, John A., Gelino, Dawn M., Kaaret, Philip
The X-ray transient, 4U 1730-22, has not been detected in outburst since 1972, when a single outburst was detected by the Uhuru satellite. This neutron star or black hole X-ray binary is presumably...
The discovery outburst of the X-ray transient IGR J17497-2821 observed with RXTE and ATCA (2006)
Rodriguez, Jerome, Bel, Marion Cadolle, Tomsick, John A., Corbel, Stephane, Brocksopp, Catherine, Paizis, Ada, ...
We report the results of a series of RXTE and ATCA observations of the recently-discovered X-ray transient IGR J17497-2821. Our 3-200 keV PCA+HEXTE spectral analysis shows very little variations over...
The Orbit of the Eclipsing X-ray Pulsar EXO 1722-363 (2006)
Thompson, Thomas W. J., Tomsick, John A., Rothschild, Richard E., Walter, Roland
With recent and archival Rossi X-Ray Timing Explorer (RXTE) X-ray measurements of the heavily obscured X-ray pulsar EXO 1722-363 (IGR J17252-3616), we carried out a pulse timing analysis to determine...
Geometrical Distance Determination using Type I X-ray Bursts (2006)
Thompson, Thomas W. J., Rothschild, Richard E., Tomsick, John A.
With the excellent angular resolution of the Chandra X-ray Observatory, it is possible to geometrically determine the distance to variable Galactic sources, based on the phenomenon that scattered...
Identifications of Four INTEGRAL Sources in the Galactic Plane via Chandra Localizations (2006)
Tomsick, John A., Chaty, Sylvain, Rodriguez, Jerome, Foschini, Luigi, Walter, Roland, Kaaret, Philip
Hard X-ray imaging of the Galactic plane by the INTEGRAL satellite is uncovering large numbers of 20-100 keV "IGR" sources. We present results from Chandra, INTEGRAL, optical, and IR observations of...
The Inclination Angle of and Mass of the Black Hole in XTE J1118+480 (2006)
Gelino, Dawn M., Balman, Solen, Kizilouglu, Umit, Yilmaz, Arda, Kalemci, Emrah, Tomsick, John A.
We have obtained optical and infrared photometry of the quiescent soft X-ray transient XTE J1118+480. In addition to optical and J-band variations, we present the first observed H- and K_s-band...
The Low Quiescent X-Ray Luminosity of the Transient X-Ray Burster EXO 1747-214 (2005)
Tomsick, John A., Gelino, Dawn M., Kaaret, Philip
We report on X-ray and optical observations of the X-ray burster EXO 1747-214. This source is an X-ray transient, and its only known outburst was observed in 1984-1985 by the EXOSAT satellite. We...
Black Hole Spectral States and Physical Connections (2005)
The dramatic changes seen in the X-ray spectral and timing properties of accreting black hole candidates (BHCs) provide important clues about the accretion and jet formation processes that occur in...
Tomsick, John A., Lingenfelter, Richard, Corbel, Stephane, Goldwurm, Andrea, Kaaret, Philip
We report on results from a 2003 February INTEGRAL observation of the black hole candidate (BHC) 4U 1630-47 and the high energy sources in the Norma Region of the Galaxy and on RXTE and radio...
The Low Quiescent X-Ray Luminosity of the Neutron Star Transient XTE J2123-058 (2004)
Tomsick, John A., Gelino, Dawn M., Halpern, Jules P., Kaaret, Philip
We report on the first X-ray observations of the neutron star soft X-ray transient (SXT) XTE J2123-058 in quiescence, made by Chandra and BeppoSAX, as well as contemporaneous optical observations. In...
The Evolution of Accreting Black Holes in Outburst (2004)
Black hole binaries exhibit dramatic changes in their X-ray spectral and timing properties over time, providing important clues about the physical processes that occur in these systems. Black holes...
Chandra Detections of Two Quiescent Black Hole X-Ray Transients (2003)
Tomsick, John A., Corbel, Stephane, Fender, Rob, Miller, Jon M., Orosz, Jerome A., Rupen, Michael P., ...
Using the Chandra X-ray Observatory, we have detected the black hole transients V4641 Sgr and XTE J1859+226 in their low luminosity, quiescent states. The 0.3-8 keV luminosities are...
Tomsick, John A., Kalemci, Emrah, Kaaret, Philip
Using the Chandra X-ray Observatory and the Rossi X-ray Timing Explorer, we have studied the black hole candidate (BHC) X-ray transient XTE J1650-500 near the end of its 2001-2002 outburst after its...
Tomsick, John A., Kalemci, Emrah, Corbel, Stephane, Kaaret, Philip
We report on X-ray observations made with the Rossi X-ray Timing Explorer of the black hole candidate (BHC) transient XTE J1650-500 at the end of its first, and currently only, outburst. By...
X-Ray Jet Emission from the Black Hole X-Ray Binary XTE J1550-564 with Chandra in 2000 (2002)
Tomsick, John A., Corbel, Stephane, Fender, Rob, Miller, Jon M., Orosz, Jerome A., Tzioumis, Tasso, ...
We have discovered an X-ray jet due to material ejected from the black hole X-ray transient XTE J1550-564. The discovery was first reported by Corbel et al. (Science, 298, 196 and astro-ph/0210224),...
Rotational Broadening Measurement for the Neutron Star X-Ray Transient XTE J2123-058 (2002)
Tomsick, John A., Heindl, William A., Chakrabarty, Deepto, Kaaret, Philip
We used optical spectroscopy of the neutron star X-ray transient XTE J2123-058 to measure the rotational broadening of the binary companion's stellar absorption lines and determined that the...
Keck Measurement of the XTE J2123-058 Radial Velocity Curve (2001)
Tomsick, John A., Heindl, William A., Chakrabarty, Deepto, Halpern, Jules P., Kaaret, Philip
We measured the radial velocity curve of the companion of the neutron star X-ray transient XTE J2123-058. Its semi-amplitude (K_2) of 298.5 +/- 6.9 km/s is the highest value that has been measured...
Tomsick, John A., Corbel, Stephane, Kaaret, Philip
We report on the evolution of the X-ray energy spectrum for the black hole candidate (BHC) X-ray transient XTE J1550-564 during the decay of the 2000 outburst. The Rossi X-ray Timing Explorer (RXTE)...
X-Ray Observations of XTE J1550-564 During the Decay of the 2000 Outburst - II. Timing (2001)
Kalemci, Emrah, Tomsick, John A., Rothschild, R. E., Pottschmidt, Katja, Kaaret, Philip
We investigate the timing behavior of XTE J1550-564 with the Rossi X-ray Timing Explorer (RXTE) as the source made a transition to the hard state during the decay of the 2000 outburst. We detect a...
Tomsick, John A., Kaaret, Philip
We present a study of the properties of strong 0.8-3.0 Hz quasi-periodic oscillations (QPOs) that occurred during 1997 RXTE observations of the microquasar GRS 1915+105 in the low-hard state. The...
Tomsick, John A., Kaaret, Philip
We report on the X-ray spectral and timing behavior of the recurrent X-ray transient 4U 1630-47 for 51 RXTE observations made during the decay of its 1998 outburst. The observations began when the...
XTE J2123-058: A New Neutron Star X-Ray Transient (1999)
Tomsick, John A., Halpern, Jules P., Kemp, Jonathan, Kaaret, Philip
We report on optical and RXTE observations of a new high-latitude bursting X-ray transient, XTE J2123-058. We identified the optical counterpart, measured the 5.9573 hr orbital period and constrained...
Broad-band X-Ray Spectra of the Black Hole Candidate GRO J1655-40 (1998)
Tomsick, John A., Kaaret, Philip, Kroeger, Richard A., Remillard, Ronald A.
We present broad-band (2 keV to 2 MeV) X-ray spectra of GRO J1655-40, a luminous X-ray transient and occasional source of relativistic radio jets, obtained with RXTE and OSSE. In one observation, the...