Discovery of a 552 Hz burst oscillation in the low-mass X-ray binary EXO 0748-676 (2009)
Galloway, Duncan K., Lin, Jinrong, Chakrabarty, Deepto, Hartman, Jacob M.
We report the detection of pulsations at 552 Hz in the rising phase of two type-I (thermonuclear) X-ray bursts observed from the accreting neutron star EXO 0748-676 in 2007 January and December, by...
A Further Drop into Quiescence by the Eclipsing Neutron Star 4U 2129+47 (2009)
Lin, Jinrong, Nowak, Michael A., Chakrabarty, Deepto
The low mass X-ray binary 4U 2129+47 was discovered during a previous X-ray outburst phase and was classified as an accretion disk corona source. A 1% delay between two mid-eclipse epochs measured...
A Mid-Infrared Counterpart to the Magnetar 1E 2259+586 (2009)
Kaplan, David L., Chakrabarty, Deepto, Wang, Zhongxiang, Wachter, Stefanie
We report the discovery of a 4.5μm counterpart to the anomalous X-ray pulsar (magnetar) 1E 2259+586 with the Spitzer Space Telescope. The mid-infrared flux density is 6.3 ± 1.0μJy at 4.5μm and
Discovery of a 692.5 s period in the X-ray Binary 4U 1820-30: an indication of a superhumper? (2009)
Wang, Zhongxiang, Chakrabarty, Deepto
The X-ray source 4U 1820-30 in the globular cluster NGC 6624 is known as the most compact binary among the identified X-ray binaries. Having an orbital period of 685.0 s, the source consists of a...
A Mid-Infrared Counterpart to the Magnetar 1E 2259+586 (2009)
Kaplan, David L., Chakrabarty, Deepto, Wang, Zhongxiang, Wachter, Stefanie
We report the discovery of a 4.5 um counterpart to the anomalous X-ray pulsar (magnetar) 1E 2259+586 with the Spitzer Space Telescope. The mid-infrared flux density is 6.3+/-1.0 uJy at 4.5 um and
Patruno, Alessandro, Hartman, Jacob M., Wijnands, R., Chakrabarty, Deepto, Van Der Klis, Michiel
We present a coherent timing analysis of the 2003 outburst of the accreting millisecond pulsar XTE J1807-294. We find an upper limit for the spin frequency derivative of 5E-14 Hz/s. The sinusoidal...
Thermonuclear (Type I) X-Ray Bursts Observed by the Rossi X-Ray Timing Explorer (2008)
Galloway, Duncan K., Muno, Michael P., Hartman, Jacob M., Psaltis, Dimitrios, Chakrabarty, Deepto
We have assembled a sample of 1187 thermonuclear (type I) X-ray bursts from observations of 48 accreting neutron stars by the Rossi X-ray Timing Explorer, spanning more than 10 years. The sample...
Breaking the AMSP mould: the increasingly strange case of HETE J1900.1-2455 (2008)
Galloway, Duncan K., Morgan, Edward H., Chakrabarty, Deepto
We present ongoing Rossi X-ray Timing Explorer (RXTE) monitoring observations of the 377.3 Hz accretion-powered pulsar, HETE J1900.1-2455 Activity continues in this system more than 3 years after...
The Advanced X-ray Timing Array (AXTAR) (2008)
Chakrabarty, Deepto, Ray, Paul S., Strohmayer, Tod E., Collaboration, For The AXTAR
AXTAR is an X-ray observatory mission concept, currently under study in the U.S., that combines very large collecting area, broadband spectral coverage, high time resolution, highly flexible...
The Spin Distribution of Millisecond X-ray Pulsars (2008)
The spin frequency distribution of accreting millisecond X-ray pulsars cuts off sharply above 730 Hz, well below the breakup spin rate for most neutron star equations of state. I review several...
Hartman, Jacob M., Watts, Anna L., Chakrabarty, Deepto
Soft phase lags, in which X-ray pulses in lower energy bands arrive later than pulses in higher energy bands, have been observed in nearly all accretion-powered millisecond pulsars, but their origin...
Hard X-ray detection and timing of accretion-powered pulsars with BATSE (2008)
NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document. The BATSE all-sky monitor on the Compton Gamma Ray Observatory is a superb tool for...
A Bursting Radio Transient in the Direction of the Galactic Center (2008)
Ray, Paul S., Hyman, Scott D., Lazio, T. Joseph, Kassim, Namir E., Roy, Subhashis, Kaplan, David L., ...
The radio sky is poorly sampled for rapidly varying transients because of the narrow field-of-view of most imaging radio telescopes at cm and shorter wavelengths. The emergence of sensitive long...
Timing and spectral properties of the accreting millisecond pulsar SWIFT J1756.9-2508 (2008)
Linares, Manuel, Wijnands, Rudy, Van Der Klis, Michiel, Krimm, Hans, Markwardt, Craig, Chakrabarty, Deepto
SWIFT J1756.9-2508 is one of the few accreting millisecond pulsars (AMPs) discovered to date. We report here the results of our analysis of its aperiodic X-ray variability, as measured with the Rossi...
Neutron Star Mass Measurements. I. Radio Pulsars (2007)
Thorsett Joseph Henry, Deepto Chakrabarty
There are now about fifty known radio pulsars in binary systems, including at least five in double neutron star binaries. In some cases, the stellar masses can be directly determined from...
Lars Bildsten, Deepto Chakrabarty, John Chiu, Mark H. Finger, Danny T. Koh, Mark Stollberg, ...
We summarize 5 years of continuous monitoring of accretion-powered pulsars with the Burst and Transient Source Experiment (BATSE) on the Compton Gamma Ray Observatory. Our 20È70 keV observations...
Robert W. Nelson, Lars Bildsten, Deepto Chakrabarty, Mark H. Finger, Danny T. Koh, Thomas A. Prince, ...
Dramatic torque reversals between spin-up and spin-down have been observed in half of the persistent X-ray pulsars monitored by the BATSE all-sky monitor on the Compton Gamma Ray Observatory....
Deepto Chakrabarty, Lars Bildsten, Mark H. Finger, Robert W. Nelson, Thomas A. Prince, Brian A. Vaughan, ...
To appear in The Astrophysical Journal Letters Over five years of daily hard X-ray (?20 keV) monitoring of the 2 min accretion-powered pulsar GX 1+4 with the Compton Gamma Ray Observatory /BATSE...
Danny T. Koh, Lars Bildsten, Deepto Chakrabarty, Robert W. Nelson, Thomas A. Prince, Brian A. Vaughan, ...
The accreting pulsar GX 301--2 (P = 680 s) has been observed continuously by the large area detectors of the Burst and Transient Source Experiment (BATSE) instrument on the Compton Gamma Ray...
Deepto Chakrabarty, Towsian Koh, Lars Bildsten, Thomas A. Prince, Mark H. Finger, Robert B. Wilson, ...
We have detected an 18.7 s accreting X-ray pulsar in the Cygnus region, using the BATSE large-area detectors on the Compton Gamma Ray Observatory. GRO J1948+32 has been localized to within 10 deg 2...
OBSERVATIONS OF ACCRETING PULSARS (2007)
Thomas A. Prince, Lars Bildsten, Deepto Chakrabarty, Robert B. Wilson, Mark H. Finger
We discuss recent observations of accreting binary pulsars with the allsky BATSE instrument on the Compton Gamma Ray Observatory. BATSE has detected and studied nearly half of the known accreting...
Deepto Chakrabarty, Lars Bildsten, John M. Grunsfeld, Danny T. Koh, Thomas A. Prince, Brian A. Vaughan, ...
Over five years of hard X-ray (20--60 keV) monitoring of the 7.66 s accretionpowered pulsar 4U 1626--67 with the Compton/BATSE large-area detectors have revealed that the neutron star is now steadily...
Mark H. Finger, Lars Bildsten, Deepto Chakrabarty, Thomas A. Prince, D. Matthew Scott, Colleen A. Wilson, ...
We present observations of a series of 10 outbursts of pulsed hard X-ray Ñux from the transient 10.6 mHz accreting pulsar GS 1843[02, using the Burst and Transient Source Experiment on the Compton...
Danny T. Koh, Lars Bildsten, Deepto Chakrabarty, Robert W. Nelson, Thomas A. Prince, ...
The accreting pulsar GX 301[2 (P\680 s) has been observed continuously by the large-area detectors of the Burst and Transient Source Experiment (BATSE) instrument on the Compton Gamma Ray Observatory...
OBSERVATIONS OF ACCRETING PULSARS (2007)
Lars Bildsten, Deepto Chakrabarty, John Chiu, Mark H. Finger, Danny T. Koh, Robert W. Nelson, ...
We summarize ve years of continuous monitoring of accretion-powered pulsars with the Burst and Transient Source Experiment (BATSE) on the Compton Gamma Ray Observatory. Our 20{70 keV observations...
bildsten @ re.berkeley.edu (2007)
Colleen A. Wilson, Mark H. Finger, B. Alan Harmon, D. Matthew Scott, Robert B. Wilson, Lars Bildsten, ...
GS 0834{430, a 12.3 second accretion-powered pulsar, has been observed in seven outbursts with the BATSE large area detectors on the Compton Gamma Ray Observatory. The rst 5 outbursts observed by...
Hartman, Jacob M., Patruno, Alessandro, Chakrabarty, Deepto, Kaplan, David L., Markwardt, Craig B., Morgan, Edward H., ...
We present a 7 yr timing study of the 2.5 ms X-ray pulsar SAX J1808.4-3658, an X-ray transient with a recurrence time of ~2 yr, using data from the Rossi X-ray Timing Explorer covering 4 transient...
The cold neutron star in the soft X-ray transient 1H 1905+000 (2007)
Jonker, Peter G., Steeghs, Daniel, Chakrabarty, Deepto, Juett, Adrienne M.
We report on our analysis of 300 ks of Chandra observations of the neutron star soft X-ray transient 1H1905+000 in quiescence. We do not detect the source down to a 95% confidence unabsorbed flux...
High-resolution X-ray spectroscopy of the ultracompact LMXB pulsar 4U 1626-67 (2006)
Krauss, Miriam I., Schulz, Norbert S., Chakrabarty, Deepto, Juett, Adrienne M., Cottam, Jean
[abridged] We report results from four recent observations of the ultracompact LMXB pulsar 4U 1626-67. All the observations obtained high-resolution X-ray spectra of the system, two from the Chandra...
Intermittent pulsations in an accretion-powered millisecond pulsar (2006)
Galloway, Duncan K., Morgan, Edward H., Krauss, Miriam I., Kaaret, Philip, Chakrabarty, Deepto
We describe observations of the seventh accretion-powered millisecond pulsar, HETE J1900.1-2455 made with the Rossi X-ray Timing Explorer during the year of activity that followed its discovery in...
Thermonuclear (type-I) X-ray bursts observed by the Rossi X-ray Timing Explorer (2006)
Galloway, Duncan K., Muno, Michael P., Hartman, Jacob M., Psaltis, Dimitrios, Chakrabarty, Deepto
We have assembled a sample of 1187 thermonuclear (type-I) X-ray bursts from 48 accreting neutron stars by the Rossi X-ray Timing Explorer, spanning more than ten years. The sample contains examples...
A Search for Fallback Disks in Four Young Supernova Remnants (2006)
Wang, Zhongxiang, Kaplan, David L., Chakrabarty, Deepto
We report on our search for the optical/infrared counterparts to the central compact objects in four young supernova remnants: Pup A, PKS 1209-52, RCW 103, and Cas A. The X-ray point sources in these...
Juett, Adrienne M., Schulz, Norbert S., Chakrabarty, Deepto, Gorczyca, Thomas W.
We present high-resolution spectroscopy of the neon K-shell and iron L-shell interstellar absorption edges in nine X-ray binaries using the High Energy Transmission Grating Spectrometer (HETGS)...
A Debris Disk Around An Isolated Young Neutron Star (2006)
Wang, Zhongxiang, Chakrabarty, Deepto, Kaplan, David L.
Pulsars are rotating, magnetized neutron stars that are born in supernova explosions following the collapse of the cores of massive stars. If some of the explosion ejecta fails to escape, it may fall...
Juett, Adrienne M., Chakrabarty, Deepto
We present the high-resolution Chandra X-ray Observatory persistent (non-dip) spectrum of 4U 1916-05 which revealed narrow absorption lines from hydrogenic neon, magnesium, silicon, and sulfur, in...
8.012 Physics I: Classical Mechanics, Fall 2005 (2005)
Elementary mechanics, presented at greater depth than in 8.01. Newton's laws, concepts of momentum, energy, angular momentum, rigid body motion, and non-inertial systems. Uses elementary calculus...
Galloway, Duncan, Psaltis, Dimitrios, Muno, Michael P., Chakrabarty, Deepto
We analyzed 123 thermonuclear (type-I) X-ray bursts observed by the Rossi X-ray Timing Explorer from the low-mass X-ray binary 4U 1636-536. All but two of the 40 radius-exansion bursts in this sample...
Krauss, Miriam I., Wang, Zhongxiang, Dullighan, Allyn, Juett, Adrienne M., Kaplan, David L., Chakrabarty, Deepto, ...
We report the precise optical and X-ray localization of the 3.2 ms accretion-powered X-ray pulsar XTE J1814-338 with data from the Chandra X-Ray Observatory as well as optical observations conducted...
X-ray Spectroscopy of Candidate Ultracompact X-ray Binaries (2005)
Juett, Adrienne M., Chakrabarty, Deepto
We present high-resolution spectroscopy of the neutron star/low-mass X-ray binaries (LMXBs) 4U 1850-087 and 4U 0513-40 as part of our continuing study of known and candidate ultracompact binaries....
Millisecond Pulsars in X-Ray Binaries (2004)
Despite considerable evidence verifying that millisecond pulsars are spun up through sustained accretion in low-mass X-ray binaries (LMXBs), it has proven surprisingly difficult to actually detect...
Juett, Adrienne M., Schulz, Norbert S., Chakrabarty, Deepto
(Abbrev.) We present high-resolution spectroscopy of the oxygen K-shell interstellar absorption edge in 7 X-ray binaries using the HETGS onboard Chandra. Using the brightest sources as templates, we...
The Effect of Neutron Star Rotation on the Properties of Thermonuclear X-ray Bursts (2003)
Muno, Michael P., Galloway, Duncan K., Chakrabarty, Deepto
Previously, observations with the Rossi X-ray Timing Explorer showed that millisecond oscillations occur preferentially in thermonuclear X-ray bursts with photospheric radius expansion from sources...
Quasi-periodic X-ray brightness fluctuations in an accreting millisecond pulsar (2003)
Wijnands, Rudy, Van Der Klis, Michiel, Homan, Jeroen, Chakrabarty, Deepto, Markwardt, Craig B., Morgan, Ed H.
The relativistic plasma flows onto neutron stars that are accreting material from stellar companions can be used to probe strong-field gravity as well as the physical conditions in the...
Nuclear-Powered Millisecond Pulsars and the Maximum Spin Frequency of Neutron Stars (2003)
Chakrabarty, Deepto, Morgan, Edward H., Muno, Michael P., Galloway, Duncan K., Wijnands, Rudy, Van Der Klis, Michiel, ...
Millisecond pulsars are neutron stars (NSs) that are thought to have been spun-up by mass accretion from a stellar companion. It is unknown whether there is a natural brake for this process, or if it...
The Energy Dependence of Millisecond Oscillations in Thermonuclear X-ray Bursts (2003)
Muno, Michael P., Ozel, Feryal, Chakrabarty, Deepto
We examine the energy-resolved pulse profiles of 51 flux oscillations observed during the decline of thermonuclear X-ray bursts from accreting weakly- magnetized neutron stars with the Rossi X-ray...
X-ray Spectroscopy of the Accreting Millisecond Pulsar XTE J0929-314 in Outburst (2002)
Juett, Adrienne M., Galloway, Duncan K., Chakrabarty, Deepto
We present the high-resolution spectrum of the accretion-powered millisecond pulsar XTE J0929-314 during its 2002 outburst, measured using the Low Energy Transmission Grating Spectrometer onboard the...
Galloway, Duncan K., Psaltis, Dimitrios, Chakrabarty, Deepto, Muno, Michael P.
We investigate the limitations of thermonuclear X-ray bursts as a distance indicator for the weakly-magnetized accreting neutron star 4U 1728-34. We measured the unabsorbed peak flux of 81 bursts in...
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...
The Likely Near-Infrared Counterpart to the Anomalous X-Ray Pulsar 1E 1048.1-5937 (2002)
Wang, Zhongxiang, Chakrabarty, Deepto
We report our discovery of the likely near-infrared counterpart to the anomalous X-ray pulsar (AXP) 1E1048.1-5937, using observations from the 6.5-m Baade (Magellan-I) telescope in Chile. We derived...
Discovery of a High-Latitude Accreting Millisecond Pulsar in an Ultracompact Binary (2002)
Galloway, Duncan, Chakrabarty, Deepto, Morgan, Edward, Remillard, Ronald
We have identified the third known accretion-powered millisecond pulsar, XTE J0929-314, with the Rossi X-Ray Timing Explorer. The source is a faint, high-Galactic-latitude X-ray transient (d >~ 5...
Juett, Adrienne, Chakrabarty, Deepto
We present high-resolution spectroscopy of the neutron-star/low-mass X-ray binaries 2S 0918-549 and 4U 1543-624 with the High Energy Transmission Grating Spectrometer onboard the Chandra X-ray...
Muno, Michael P., Ozel, Feryal, Chakrabarty, Deepto
We present a comprehensive observational and theoretical analysis of the amplitudes and profiles of oscillations that occur during thermonuclear X-ray bursts from weakly-magnetized neutron stars in...
The Frequency Stability of Millisecond Oscillations in Thermonuclear X-Ray Bursts (2002)
Muno, Michael P., Chakrabarty, Deepto, Galloway, Duncan K., Psaltis, Dimitrios
We analyze the frequency evolution of millisecond oscillations observed during type I X-ray bursts with the Rossi X-ray Timing Explorer in order to establish the stability of the mechanism underlying...
The X-Ray Position and Infrared Counterpart of the Eclipsing X-Ray Pulsar OAO 1657-415 (2002)
Chakrabarty, Deepto, Wang, Zhongxiang, Juett, Adrienne M., Lee, Julia C., Roche, Paul
We have measured the precise position of the 38-s eclipsing X-ray pulsar OAO 1657-415 with the Chandra X-Ray Observatory: RA = 17h00m48.90s, Dec = -41d39m21.6s, equninox J2000, error radius = 0.5...
Chandra High-Resolution Spectrum of the Anomalous X-ray Pulsar 4U 0142+61 (2002)
Juett, Adrienne M., Marshall, Herman L., Chakrabarty, Deepto, Schulz, Norbert S.
We report on a 25 ks observation of the 8.7 s anomalous X-ray pulsar 4U~0142+61 with the High Energy Transmission Grating Spectrometer (HETGS) on the Chandra X-ray Observatory. The continuum spectrum...
Wang, Zhongxiang, Chakrabarty, Deepto
We report on our search for the optical counterparts of the Southern Hemisphere anomalous X-ray pulsar 1E1048.1-5937 and the radio-quiet neutron stars in supernova remnants Puppis A, RCW 103, and PKS...
15 Years Going Steady - Timing the Magnetar 1E 1841-045 (2001)
Gotthelf, E. V., Gavriil, F. P., Kaspi, V. M., Vasisht, G., Chakrabarty, Deepto
We report on a long-term monitoring campaign of 1E 1841-045, the 12-s anomalous X-ray pulsar and magnetar candidate at the center of the supernova remnant Kes 73. We have obtained approximately...
Long-Term Monitoring of Anomalous X-ray Pulsars (2001)
Gavriil, Fotis P., Kaspi, Victoria M., Chakrabarty, Deepto
We report on long-term monitoring of anomalous X-ray pulsars (AXPs) using the Rossi X-ray Timing Explorer. Using phase-coherent timing, we find a wide variety of behaviors among the sources, ranging...
Chandra/HETGS Spectroscopy of the Anomalous X-ray Pulsar 4U 0142+61 (2001)
Juett, Adrienne M., Marshall, Herman L., Chakrabarty, Deepto, Canizares, Claude R., Schulz, Norbert S.
We report on a 25 ks observation of the anomalous X-ray pulsar 4U 0142+61 with the High Energy Transmission Grating Spectrometer (HETGS) on the Chandra X-ray Observatory. The continuum spectrum is...
How Do Z and Atoll X-ray Binaries Differ? (2001)
Muno, Michael P., Remillard, Ronald A., Chakrabarty, Deepto
Low-mass X-ray binaries containing weakly magnetized neutron stars may be divided into two classes, Z and atoll sources, based in large part upon the patterns which they trace in plots of two X-ray...
Wang, Zhongxiang, Chakrabarty, Deepto, Roche, Paul, Charles, Philip A., Kuulkers, Erik, Shahbaz, Tariq, ...
We present multiband optical/infrared photometry of V4580 Sgr, the optical counterpart of the accretion-powered millisecond pulsar SAX J1808.4-3658, taken during the 1998 X-ray outburst of the...
Double-Peaked X-Ray Lines from the Oxygen/Neon-Rich Accretion Disk in 4U1626-67 (2001)
Schulz, Norbert S., Chakrabarty, Deepto, Marshall, Herman L., Canizares, Claude R., Lee, Julia C., Houck, John
We report on a 39 ks observation of the 7.7-s low-mass X-ray binary pulsar 4U1626-67 with the High Energy Transmission Grating Spectrometer (HETGS) on the Chandra X-Ray Observatory. This ultracompact...
Ultracompact X-Ray Binaries with Neon-Rich Degenerate Donors (2001)
Juett, Adrienne M., Psaltis, Dimitrios, Chakrabarty, Deepto
There are three low-mass X-ray binaries (4U 0614+091, 2S 0918-549, and 4U 1543-624) for which broad line emission near 0.7 keV was previously reported. A recent high-resolution observation of 4U...
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...
Millihertz Optical/UV Oscillations in 4U 1626-67: Evidence for a Warped Accretion Disk (2001)
Chakrabarty, Deepto, Homer, Lee, Charles, Philip A., O'Donoghue, Darragh
We have detected large-amplitude 0.3-1.2 mHz quasi-periodic oscillations (QPOs) from the low-mass X-ray binary pulsar 4U 1626-67/KZ TrA, using UV photometry from HST and ground-based optical...
The erratic luminosity behavior of SAX J1808.4-3658 during its 2000 outburst (2001)
Wijnands, Rudy, Mendez, Mariano, Markwardt, Craig, Van Der Klis, Michiel, Chakrabarty, Deepto, Morgan, Ed
We report on the highly variable and erratic long-term X-ray luminosity behavior of the only known accretion-driven millisecond X-ray pulsar SAX J1808.4-3658 during its 2000 outburst, as observed...
Millisecond Oscillations and Photospheric Radius Expansion in Thermonuclear X-Ray Bursts (2001)
Muno, Michael P., Chakrabarty, Deepto, Galloway, Duncan K., Savov, Pavlin
We use archival data from the Rossi X-Ray Timing Explorer to examine 125 type I X-ray bursts from the 9 weakly magnetic accreting neutron stars where millisecond oscillations have been detected...
A Brown Dwarf Companion for the Accreting Millisecond Pulsar SAX J1808.4-3658 (2001)
Bildsten, Lars, Chakrabarty, Deepto
BeppoSAX has revealed a population of faint neutron star X-ray transients in the Galactic bulge. King conjectured that these neutron stars are accreting from brown dwarfs (BD) with a time-averaged...
Anomalous X-ray Pulsars and Soft gamma-ray Repeaters: Spectral Fits and the Magnetar Model (2001)
Perna, Rosalba, Heyl, Jeremy, Hernquist, Lars, Juett, Adrienne, Chakrabarty, Deepto
The energy source powering the X-ray emission from anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs) is still uncertain. In one scenario, the presence of an ultramagnetized neutron...
Wang, Zhongxiang, Chakrabarty, Deepto, Roche, Paul, Charles, Philip A., Kuulkers, Erik, Shahbaz, Tariq, ...
We present multiband optical/IR photometry of V4580 Sgr, the optical counterpart of the accretion-powered millisecond pulsar SAX J1808.4-3658, taken during the 1998 X-ray outburst of the system. The...
Wang, Zhongxiang, Chakrabarty, Deepto, Roche, Paul, Charles, Philip A., Kuulkers, Erik, Shahbaz, Tariq, ...
We present multiband optical/IR photometry of V4580 Sgr, the optical counterpart of the accretion-powered millisecond pulsar SAX J1808.4-3658, taken during the 1998 X-ray outburst of the system. The...
Wang, Zhongxiang, Chakrabarty, Deepto, Roche, Paul, Charles, Philip A., Kuulkers, Erik, Shahbaz, Tariq, ...
We present multiband optical/IR photometry of V4580 Sgr, the optical counterpart of the accretion-powered millisecond pulsar SAX J1808.4-3658, taken during the 1998 X-ray outburst of the system. The...
Wang, Zhongxiang, Chakrabarty, Deepto, Roche, Paul, Charles, Philip A., Kuulkers, Erik, Shahbaz, Tariq, ...
We present multiband optical/IR photometry of V4580 Sgr, the optical counterpart of the accretion-powered millisecond pulsar SAX J1808.4-3658, taken during the 1998 X-ray outburst of the system. The...
Wang, Zhongxiang, Chakrabarty, Deepto, Roche, Paul, Charles, Philip A., Kuulkers, Erik, Shahbaz, Tariq, ...
We present multiband optical/IR photometry of V4580 Sgr, the optical counterpart of the accretion-powered millisecond pulsar SAX J1808.4-3658, taken during the 1998 X-ray outburst of the system. The...
Long-Term RXTE Monitoring of the Anomalous X-ray Pulsar 1E 1048.1-5937 (2000)
Kaspi, Victoria M., Gavriil, Fotis P., Chakrabarty, Deepto, Lackey, Jessica R., Muno, Michael P.
We report on long-term monitoring of the anomalous X-ray pulsar (AXP) 1E 1048.1-5937 using the Rossi X-ray Timing Explorer (RXTE). The timing behavior of this pulsar is different from that of other...
Discovery of a 270 Hz X-Ray Burst Oscillation in the X-Ray Dipper 4U 1916-053 (2000)
Galloway, Duncan K., Chakrabarty, Deepto, Muno, Michael P., Savov, Pavlin
We report the discovery of a highly coherent oscillation in a type-I X-ray burst observed from 4U 1916-053 by the Rossi X-ray Timing Explorer (RXTE). The oscillation was most strongly detected...
Yokogawa, Jun, Paul, Biswajit, Ozaki, Masanobu, Nagase, Fumiaki, Chakrabarty, Deepto, Takeshima, Toshiaki
The new transient X-ray pulsar XTE J0111.2-7317 was observed with Advanced Satellite for Cosmology and Astrophysics (ASCA) on 1998 November 18, a few days after its discovery with the Proportional...
The Central X-Ray Point Source in Cassiopeia A (2000)
Chakrabarty, Deepto, Pivovaroff, Michael J., Hernquist, Lars E., Heyl, Jeremy S., Narayan, Ramesh
The spectacular first light observation by the Chandra X-Ray Observatory revealed an X-ray point source near the center of the 300 yr old Cas A supernova remnant. We present an analysis of the public...
Precision Timing of Two Anomalous X-Ray Pulsars (1999)
Kaspi, Victoria M., Chakrabarty, Deepto, Steinberger, Julia
We report on long-term X-ray timing of two anomalous X-ray pulsars, 1RXS J170849.0-400910 and 1E 2259+586, using the Rossi X-ray Timing Explorer. In monthly observations made over 1.4 yr and 2.6 yr...
The Outbursts and Orbit of the Accreting Pulsar GS 1843-02 = 2S 1845-024 (1998)
Finger, Mark H., Bildsten, Lars, Chakrabarty, Deepto, Prince, Thomas A., Scott, D. Matthew, Wilson, Colleen A., ...
We present observations of a series of 10 outbursts of pulsed hard X-ray flux from the transient 10.6 mHz accreting pulsar GS 1843-02, using the Burst and Transient Source Experiment on the Compton...
Psaltis, Dimitrios, Chakrabarty, Deepto
The recent discovery of the first known accretion-powered millisecond pulsar with the Rossi X-Ray Timing Explorer provides the first direct probe of the interaction of an accretion disk with the...
The two-hour orbit of a binary millisecond X-ray pulsar (1998)
Chakrabarty, Deepto, Morgan, Edward H.
Typical radio pulsars are magnetized neutron stars that are born rapidly rotating and slow down as they age on time scales of 10 to 100 million years. However, millisecond radio pulsars spin very...
Neutron Star Mass Measurements. I. Radio Pulsars (1998)
Thorsett, S. E., Chakrabarty, Deepto
There are now about fifty known radio pulsars in binary systems, including at least five in double neutron star binaries. In some cases, the stellar masses can be directly determined from...
Discovery of the 198 s X-ray Pulsar GRO J2058+42 (1998)
Wilson, Colleen A., Finger, Mark H., Harmon, B. Alan, Chakrabarty, Deepto, Strohmayer, Tod
GRO J2058+42, a transient 198 second x-ray pulsar, was discovered by the Burst and Transient Source Experiment (BATSE) on the Compton Gamma-Ray Observatory (CGRO), during a "giant" outburst in 1995...
Warped Disks as a Possible Origin of Torque Reversals in Accretion-Powered Pulsars (1998)
Van Kerkwijk, M. H., Chakrabarty, Deepto, Pringle, J. E.
Enigmatic transitions between spin-up and spin-down have been observed in several X-ray pulsars accreting matter via an accretion disk. In these transitions, the torque changes sign but remains at...
Infrared Spectroscopy of GX 1+4/V2116 Oph: Evidence for a Fast Red Giant Wind? (1998)
Chakrabarty, Deepto, Van Kerkwijk, Marten H., Larkin, James E.
We present infrared spectroscopy of the low-mass X-ray binary GX 1+4/V2116 Oph. This symbiotic binary consists of a 2-min accretion-powered pulsar and an M5 III red giant. A strong He I 1.083 micron...
A Search for Optical Pulsations from Two Young Southern Pulsars (1998)
Chakrabarty, Deepto, Kaspi, Victoria M.
We report on high-speed optical photometry of the radio positions of two young rotation-powered pulsars. No pulsations were detected from the optical counterpart proposed by Caraveo et al. (1994) for...
On the Dramatic Spin-up/Spin-down Torque Reversals in Accreting Pulsars (1997)
Nelson, Robert W., Bildsten, Lars, Chakrabarty, Deepto, Finger, Mark H., Koh, Danny T., Prince, Thomas A., ...
Dramatic torque reversals between spin up and spin down have been observed in half of the persistent X-ray pulsars monitored by the BATSE all-sky monitor on CGRO. Theoretical models developed to...
Observations of Accreting Pulsars (1997)
Bildsten, Lars, Chakrabarty, Deepto, Chiu, John, Finger, Mark H., Koh, Danny T., Nelson, Robert W., ...
We summarize five years of continuous monitoring of accretion-powered pulsars with the Burst and Transient Source Experiment (BATSE) on the Compton Gamma Ray Observatory. Our 20-70 keV observations...
The Symbiotic Neutron Star Binary GX 1+4/V2116 Ophiuchi (1997)
Chakrabarty, Deepto, Roche, Paul
We present multiwavelength observations of this S-type symbiotic LMXB which consists of a 2-min X-ray pulsar accreting from an M6 III giant. This is the only symbiotic system definitely known to...
High-Speed Optical Photometry of the Ultracompact X-ray Binary 4U 1626-67 (1997)
Rapid UBVRI photometry of this ultracompact LMXB pulsar has detected 7.67 s optical pulsations in all five bands. The optical pulsations, which are at the same frequency as the X-ray pulsations, are...
On the Correlation of Torque and Luminosity in GX 1+4 (1997)
Chakrabarty, Deepto, Bildsten, Lars, Finger, Mark H., Grunsfeld, John M., Koh, Danny T., Nelson, Robert W., ...
Over five years of daily hard X-ray (>20 keV) monitoring of the 2-min accretion-powered pulsar GX 1+4 with the Compton Gamma Ray Observatory/BATSE large-area detectors has found nearly continuous...
Hard X-Ray Detection and Timing of Accretion-Powered Pulsars with BATSE (1996)
The BATSE all-sky monitor on the Compton Gamma Ray Observatory is a superb tool for the study of accretion-powered pulsars. In the #rst part of this thesis, I describe its capabilities for hard X-ray...
Hard X-ray detection and timing of accretion-powered pulsars with BATSE (1995)
NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document. The BATSE all-sky monitor on the Compton Gamma Ray Observatory is a superb tool for...