Sciences and Exploration Directorate

Tod E Strohmayer


Tod E Strohmayer's Contact Card & Information.
Phone: 301.286.1256
Org Code: 662
Mail Code 662
Greenbelt, MD 20771

Brief Bio

Tod was born and raised in New York (Long Island to be precise), where during his formative years he developed a keen interest in science and hockey, but not necessarily in that order. In 1985 he graduated with a degree in Physics (BS) from Rensselaer Polytechnic Institute (RPI) and then moved West to the University of Rochester (NY) to do graduate work in astrophysics. Under the supervision of Hugh van Horn his PhD, "On Observing Neutron Star Oscillations", was completed in 1992. After that he continued to drift westward, landing at Los Alamos National Lab, where he worked with Ed Fenimore on coded mask imaging, gamma-ray burst science and assorted neutron star physics. He came back East to Goddard in Summer 1994 to work on the Rossi X-ray Timing Explorer (RXTE) Proportional Counter Array (PCA) science team led by Jean Swank. He carries out a diverse research program focused primarily on the physics of compact stellar remnants, and tries to play a game of soccer now and again.

Research Interests

Physics of Compact Stellar Remnants

Astrophysics: X-ray Binaries & CVs

Tod's research focuses on the physics of compact stellar remnants: neutron stars, black holes and white dwarfs. Specific areas of study include, X-ray Binaries; Neutron Stars; Black Holes; Compact White Dwarf Binaries; Ultra-luminous X-ray sources; Soft Gamma Repeaters; Gamma-Ray Bursts. Tod's research uses high energy observations of these objects, particularly in the X-ray band, to understand their basic properties and reveal the extreme physics that governs their structure and dynamics. 

Current Projects

NICER (Neutron Star Interior Composition Explorer)


Tod is a Co-Investigator on the NICER project and member of the NICER Science Team. NICER is an X-ray observatory attached to the International Space Station, optimized for high throughput observations of dynamic phenomena associated with compact stars and other cosmic X-ray sources, especially neutron stars. He is involved with a diverse range of science projects utilizing NICER data for both neutron stars and black holes, and also supports the NICER Guest Observer Facility (GOF).

NuSTAR (Nuclear Spectroscopic Telescope Array)

NuSTAR is a NASA Small Explorer mission launched in 2012, and is the first focusing high-energy X-ray mission, enabling the hard X-ray sky above 10 keV to be studied sensitively for the first time. Tod supports NuSTAR as the Mission Scientist, and provides support and oversight to the NuSTAR Guest Investigator program.

Rossi X-ray Timing Explorer (RXTE)

X-ray Binaries & CVs

Tod was the Project Scientist for RXTE for the final three years of the project, and the Deputy Project Scientist for the three years prior to that. The mission completed a remarkable 16 years of science operations in 2012 and is now in a close-out and archival phase. Tod continues to support RXTE by answering questions submitted to the HEASARC help-desk regarding RXTE and its archival data.

X-ray Polarimetry

Black Holes

Tod was a GEMS (Gravity and Extreme Magnetism SMEX) Co-Investigator and a member of the science team. When completed, GEMS would have carried out the first sensitive survey of the X-ray polarization properties of many classes of X-ray sources, including accreting black holes, neutron stars, pulsars and AGN. However, the project was not confirmed for development beyond phase B. Tod remains involved with ongoing efforts in the X-ray branch to realize an X-ray polarimetry mission, and was also a Co-Investigator of the PRAXYS Small Explorer proposal. His work in this area is primarily in data analysis, calibration and science interpretation.


Senior Astrophysicist

NASA/GSFC - NASA's Goddard Space Flight Center, Greenbelt, MD

May 1998 - Present

Fellow, Goddard Space Flight Center/University of Maryland Joint Space-Science Institute (JSI)

GSFC - Goddard Space Flight Center and the University of Maryland, College Park

May 2011 - Present

Tod is a Fellow of the Joint Space-Science Institute (JSI), a collaborative partnership between Goddard Space Flight Center and the University of Maryland. JSI brings together scientists from the UMD Departments of Physics and Astronomy, and the GSFC Astrophysics Science Division, and is dedicated to fostering new areas of research at the interface of physics and space astronomy. Tod collaborates with scientists in the UMD Department of Astronomy, and has collaborated with the nuclear theory group in the UMD Department of Physics.


  • 1992 - PhD (physics), "On Observing Neutron Star Oscillations", University of Rochester (NY), Rochester, NY
  • 1988 - MA physics, University of Rochester (NY), Rochester, NY
  • 1985 - BS Physics, Rensselaer Polytechnic Institute, Troy, NY

Professional Societies

American Astronomical Society (AAS)

Tod is a full member of the American Astronomical Society (AAS) and is also a member of the High Energy Astrophysics Division (HEAD) of the Society.

1992 - Present

American Physical Society (APS)

Tod is a full member of the APS, and a member of the Division of Astrophysics (DAP).

2012 - Present

Professional Service

Tod does a good deal of refereeing for the major journals of physics and astrophysics, including, The Astrophysical Journal, The Monthly Notices of the Royal Astronomical Society, Astronomy & Astrophysics, Science, Nature, and Physical Review Letters.


2019: Fellow of the American Astronomical Society (AAS) Tod was selected in the inaugural round of AAS Fellows appointments in 2019.

2015: NASA Exceptional Scientific Achievement Medal Awarded for X-ray timing studies of Ultraluminous X-ray sources (ULXs).

2015: Robert H. Goddard Award, Exceptional Achievement for Science Awarded for X-ray timing studies of Ultraluminous X-ray sources (ULXs).

2008 Astrophysics Science Division Peer Award For dedication to high quality science output of missions, and service to both the scientific and NASA communities.

2006 Bruno Rossi Prize of the High Energy Astrophysics Division (HEAD) of the American Astronomical Society (AAS) For X-ray studies with RXTE that revealed the millisecond spin periods of accreting neutron stars.

2006 NASA Exceptional Scientific Achievement Medal For development of probes of fundamental physics using X-ray studies of compact stars.

2005 NASA/GSFC Space Science Achievement Award Awarded for X-ray studies to probe the structure of matter at extreme densities.

2002 NASA Exceptional Achievement Medal Awarded for X-ray Timing studies of Black Holes.

2001 NASA/GSFC Honor Award Awarded for the discovery of 450 Hz QPO in black hole transient and microquasar GRO J1655-40, and its implications for black hole spin.

2000 NASA/GSFC John C. Lindsay Memorial Award Awarded for the discovery of the spin periods of bursting neutron stars and new methods to study the masses and radii of neutron stars.

1997 USRA High Energy Astrophysics Program Excellence in Research Award Awarded for recent studies of X-ray bursts with RXTE.

Selected Publications


2021. "Long-term Coherent Timing of the Accreting Millisecond Pulsar IGR J17062–6143." The Astrophysical Journal 912 (2): 120 [10.3847/1538-4357/abf13f] [Journal Article/Letter]

2021. "A Real-time View of Orbital Evolution in HM Cancri." The Astrophysical Journal Letters 912 (1): L8 [10.3847/2041-8213/abf3cc] [Journal Article/Letter]

2021. "NICER Discovery of Millisecond X-Ray Pulsations and an Ultracompact Orbit in IGR J17494-3030." The Astrophysical Journal 908 (1): L15 [10.3847/2041-8213/abe1b4] [Journal Article/Letter]

2020. "Timing the Pulsations of the Accreting Millisecond Pulsar SAX J1808.4–3658 during Its 2019 Outburst." The Astrophysical Journal 898 (1): 38 [10.3847/1538-4357/ab9827] [Journal Article/Letter]

2020. "NICER–NuSTAR Observations of the Neutron Star Low-mass X-Ray Binary 4U 1735–44." The Astrophysical Journal 895 (1): 45 [10.3847/1538-4357/ab89a6] [Journal Article/Letter]

2020. "The 2019 super-Eddington outburst of RX J0209.6−7427: detection of pulsations and constraints on the magnetic field strength." Monthly Notices of the Royal Astronomical Society 494 (4): 5350-5359 [10.1093/mnras/staa991] [Journal Article/Letter]

2019. "A NICER View of PSR J0030+0451: Millisecond Pulsar Parameter Estimation." The Astrophysical Journal 887 (1): L21 [10.3847/2041-8213/ab481c] [Journal Article/Letter]

2019. "PSR J0030+0451 Mass and Radius from NICER Data and Implications for the Properties of Neutron Star Matter." The Astrophysical Journal 887 (1): L24 [10.3847/2041-8213/ab50c5] [Journal Article/Letter]

2019. "Constraining the Neutron Star Mass–Radius Relation and Dense Matter Equation of State with NICER. I. The Millisecond Pulsar X-Ray Data Set." The Astrophysical Journal 887 (1): L25 [10.3847/2041-8213/ab53eb] [Journal Article/Letter]

2019. "Constraining the Neutron Star Mass–Radius Relation and Dense Matter Equation of State with NICER. II. Emission from Hot Spots on a Rapidly Rotating Neutron Star." The Astrophysical Journal 887 (1): L26 [10.3847/2041-8213/ab5968] [Journal Article/Letter]

2019. "A NICER Thermonuclear Burst from the Millisecond X-Ray Pulsar SAX J1808.4–3658." The Astrophysical Journal 885 (1): L1 [10.3847/2041-8213/ab4ae1] [Journal Article/Letter]

2019. "Searching for Hypermassive Neutron Stars with Short Gamma-Ray Bursts." The Astrophysical Journal 884 (1): L16 [10.3847/2041-8213/ab43e0] [Journal Article/Letter]

2019. "NICER Observes a Secondary Peak in the Decay of a Thermonuclear Burst from 4U 1608–52." The Astrophysical Journal 883 (1): 61 [10.3847/1538-4357/ab3a37] [Journal Article/Letter]

2019. "Observations of the Ultra-compact X-Ray Binary 4U 1543-624 in Outburst with NICER, INTEGRAL, Swift, and ATCA." The Astrophysical Journal 883 (1): 39 [10.3847/1538-4357/ab3806] [Journal Article/Letter]

2019. "Anti-glitches in the Ultraluminous Accreting Pulsar NGC 300 ULX-1 Observed with NICER." The Astrophysical Journal 879 (2): 130 [10.3847/1538-4357/ab24d8] [Journal Article/Letter]

2019. "NICER Observation of Unusual Burst Oscillations in 4U 1728-34." The Astrophysical Journal 878 (2): 145 [10.3847/1538-4357/ab20c4] [Journal Article/Letter]

2019. "NICER Discovers Spectral Lines during Photospheric Radius Expansion Bursts from 4U 1820−30: Evidence for Burst-driven Winds." The Astrophysical Journal 878 (2): L27 [10.3847/2041-8213/ab25eb] [Journal Article/Letter]

2019. "On the Curious Pulsation Properties of the Accreting Millisecond Pulsar IGR J17379–3747." The Astrophysical Journal 877 (2): 70 [10.3847/1538-4357/ab1b26] [Journal Article/Letter]

2019. "On the Persistence of QPOs during the SGR 1806−20 Giant Flare." The Astrophysical Journal 871 (1): 95 [10.3847/1538-4357/aaf5ce] [Journal Article/Letter]

2018. "NICER Discovers mHz Oscillations in the “Clocked” Burster GS 1826−238." The Astrophysical Journal 865 (1): 63 [10.3847/1538-4357/aada14] [Journal Article/Letter]

2018. "NuSTAR and NICER reveal IGR J17591–2342 as a new accreting millisecond X-ray pulsar." Astronomy & Astrophysics 617 L8 [10.1051/0004-6361/201834160] [Journal Article/Letter]

2018. "On the 2018 Outburst of the Accreting Millisecond X-Ray Pulsar Swift J1756.9–2508 As Seen with NICER." The Astrophysical Journal 864 (1): 14 [10.3847/1538-4357/aad5e5] [Journal Article/Letter]

2018. "NICER and Fermi GBM Observations of the First Galactic Ultraluminous X-Ray Pulsar Swift J0243.6+6124." The Astrophysical Journal 863 (1): 9 [10.3847/1538-4357/aace60] [Journal Article/Letter]

2018. "NICER Detects a Soft X-Ray Kilohertz Quasi-periodic Oscillation in 4U 0614+09." The Astrophysical Journal 860 (1): L9 [10.3847/2041-8213/aac893] [Journal Article/Letter]

2018. "A NICER Look at the Aql X-1 Hard State." The Astrophysical Journal 859 (1): L1 [10.3847/2041-8213/aac2e2] [Journal Article/Letter]

2018. "NICER Discovers the Ultracompact Orbit of the Accreting Millisecond Pulsar IGR J17062–6143." The Astrophysical Journal 858 (2): L13 [10.3847/2041-8213/aabf44] [Journal Article/Letter]

2018. "Detection of Reflection Features in the Neutron Star Low-mass X-Ray Binary Serpens X-1 with NICER." The Astrophysical Journal 858 (1): L5 [10.3847/2041-8213/aabee6] [Journal Article/Letter]

2018. "NICER Detection of Strong Photospheric Expansion during a Thermonuclear X-Ray Burst from 4U 1820–30." The Astrophysical Journal 856 (2): L37 [10.3847/2041-8213/aab904] [Journal Article/Letter]

2018. "NICER Observes the Effects of an X-Ray Burst on the Accretion Environment in Aql X-1." The Astrophysical Journal 855 (1): L4 [10.3847/2041-8213/aab104] [Journal Article/Letter]

2017. "Where Are the r-modes? Chandra Observations of Millisecond Pulsars." The Astrophysical Journal 840 (2): 94 [10.3847/1538-4357/aa6d62] [Journal Article/Letter]

2017. "X-Ray Spectro-polarimetry with Photoelectric Polarimeters." The Astrophysical Journal 838 (1): 72 [10.3847/1538-4357/aa643d] [Journal Article/Letter]

2017. "IGR J17062–6143 Is an Accreting Millisecond X-Ray Pulsar." The Astrophysical Journal 836 (2): L23 [10.3847/2041-8213/aa5e51] [Journal Article/Letter]

2017. "X-Ray Reflection and an Exceptionally Long Thermonuclear Helium Burst from IGR J17062-6143." The Astrophysical Journal 836 (1): 111 [10.3847/1538-4357/836/1/111] [Journal Article/Letter]

2016. "X-RAY BURST OSCILLATIONS: FROM FLAME SPREADING TO THE COOLING WAKE." The Astrophysical Journal 818 (1): 93 [10.3847/0004-637x/818/1/93] [Journal Article/Letter]

2016. "FIRST SEARCH FOR AN X-RAY–OPTICAL REVERBERATION SIGNAL IN AN ULTRALUMINOUS X-RAY SOURCE." The Astrophysical Journal 818 (1): 85 [10.3847/0004-637x/818/1/85] [Journal Article/Letter]

2014. "A Non-radial Oscillation Mode in an Accreting Millisecond Pulsar?." The Astrophysical Journal 784 (1): 72-83 [10.1088/0004-637X/784/1/72] [Journal Article/Letter]

2014. "Characterizing the Evolving X-Ray Spectral Features during a Superburst from 4U 1636-536." The Astrophysical Journal 789 121 [Full Text] [10.1088/0004-637X/789/2/121] [Journal Article/Letter]

2013. "Upper bounds on r-mode amplitudes from observations of LMXB neutron stars ." The Astrophysical Journal 773 (2): 140-149 [10.1088/0004-637X/773/2/140] [Journal Article/Letter]

2013. "On the Statistical Analysis of X-ray Polarization Measurements." The Astrophysical Journal 772 (2): 103--112 [10.1088/0004-637X/773/2/103] [Journal Article/Letter]

2013. "On the Nature of the mHz X-Ray Quasi-periodic Oscillations from Ultraluminous X-Ray Source M82 X-1: Search for Timing-Spectral Correlations." The Astrophysical Journal 771 (2): 10 [10.1088/0004-637X/771/2/101] [Journal Article/Letter]

2013. "Discovery of a 7 mHz X-Ray Quasi-periodic Oscillation from the most Massive Stellar-mass Black Hole IC 10 X-1." The Astrophysical Journal Letters 771 (2): 7 [10.1088/2041-8205/771/2/L44] [Journal Article/Letter]

2013. "Evidence for Quasi-periodic X-Ray Dips from an Ultraluminous X-Ray Source: Implications for the Binary Motion." The Astrophysical Journal 764 (1): 13 [10.1088/0004-637X/764/1/93] [Journal Article/Letter]

2012. "ADVANCES IN THE RXTE PROPORTIONAL COUNTER ARRAY CALIBRATION: NEARING THE STATISTICAL LIMIT." Astrophysical Journal 757 159 [10.1088/0004-637X/757/2/159] [Journal Article/Letter]

2012. "Low-frequency (11 mHz) Oscillations in H1743-322: A New Class of Black Hole Quasi-periodic Oscillations?." The Astrophysical Journal Letters 754 (2): 6 [10.1088/2041-8205/754/2/L23] [Journal Article/Letter]

2012. "A Multi-epoch Timing and Spectral Study of the Ultraluminous X-Ray Source NGC 5408 X-1 with XMM-Newton." The Astrophysical Journal 753 (2): 16 [10.1088/0004-637X/753/2/139] [Journal Article/Letter]

2010. "Discovery of a Second Transient Low-Mass X-ray Binary in the Globular Cluster Ngc 6440." The Astrophysical Journal 714 894 [Full Text] [10.1088/0004-637X/714/1/894] [Journal Article/Letter]

2010. "Discovery of a 20589 Hz Accreting Millisecond X-ray Pulsar in the Globular Cluster NGC 6440." The Astrophysical Journal Letters 712 L58 [Full Text] [10.1088/2041-8205/712/1/L58] [Journal Article/Letter]

2010. "Discovery of Eclipses from the Accreting Millisecond X-ray Pulsar SWIFT J17494-2807." The Astrophysical Journal Letters 717 L149 [Full Text] [10.1088/2041-8205/717/2/L149] [Journal Article/Letter]

2010. "What ignites on the neutron star of 4U 0614+091?." Astronomy and Astrophysics 514 65 [Full Text] [10.1051/0004-6361/200913210] [Journal Article/Letter]

2010. "On Relativistic Disk Spectroscopy in Compact Objects with X-ray CCD Cameras." The Astrophysical Journal 724 1441 [Full Text] [10.1088/0004-637X/724/2/1441] [Journal Article/Letter]

2010. "Relativistic Lines and Reflection from the Inner Accretion Disks Around Neutron Stars." The Astrophysical Journal 720 205 [Full Text] [10.1088/0004-637X/720/1/205] [Journal Article/Letter]

2010. "Discovery of a New Soft Gamma Repeater, SGR J1833-0832." The Astrophysical Journal 718 331 [Full Text] [10.1088/0004-637X/718/1/331] [Journal Article/Letter]

2010. "Type I X-ray bursts and burst oscillations in the accreting millisecond X-ray pulsar IGR J17511-3057." Monthly Notices of the Royal Astronomical Society 409 1136 [Full Text] [10.1111/j.1365-2966.2010.17369.x] [Journal Article/Letter]

2009. "Discovery of a 115 Day Orbital Period in the Ultraluminous X-Ray Source NGC 5408 X-1." The Astrophysical Journal Letters 706 L210 [Full Text] [10.1088/0004-637X/706/2/L210] [Journal Article/Letter]

2009. "Evidence for an Intermediate-mass Black Hole in NGC 5408 X-1." The Astrophysical Journal 703 1386 [Full Text] [10.1088/0004-637X/703/2/1386] [Journal Article/Letter]

2009. "A Smoking Gun in the Carina Nebula." The Astrophysical Journal Letters 695 L4 [Full Text] [10.1088/0004-637X/695/1/L4] [Journal Article/Letter]

2008. "Discovery of the Spin Frequency of 4U 0614+09 with the Swift Burst Alert Telescope." The Astrophysical Journal 672 L37 [Full Text] [10.1086/526546] [Journal Article/Letter]

2008. "High-Resolution X-Ray Spectroscopy of RX J08063+1527 with Chandra." The Astrophysical Journal 679 L109 [Full Text] [10.1086/589439] [Journal Article/Letter]

2008. "Relativistic Iron Emission Lines in Neutron Star Low-Mass X-Ray Binaries as Probes of Neutron Star Radii." The Astrophysical Journal 674 415 [Full Text] [10.1086/524936] [Journal Article/Letter]

2007. "Discovery of 442 Hz Pulsations from an X-Ray Source in the Globular Cluster NGC 6440." The Astrophysical Journal 669 L29 [Full Text] [10.1086/523758] [Journal Article/Letter]

2007. "Thermonuclear Flame Spreading on Rapidly Spinning Neutron Stars: Indications of the Coriolis Force?." The Astrophysical Journal 666 L85 [Full Text] [10.1086/521790] [Journal Article/Letter]

2007. "Evidence of a Broad Relativistic Iron Line from the Neutron Star Low-Mass X-Ray Binary Serpens X-1." The Astrophysical Journal 664 L103 [Full Text] [10.1086/520844] [Journal Article/Letter]

2007. "Quasi-periodic Variability in NGC 5408 X-1." The Astrophysical Journal 660 580 [Full Text] [10.1086/512723] [Journal Article/Letter]

2007. "High frequency oscillations during magnetar flares." Astrophysics and Space Science 308 625 [Full Text] [10.1007/s10509-007-9296-z] [Journal Article/Letter]

2007. "An Unusual Precursor Burst with Oscillations from SAX J18084-3658." The Astrophysical Journal 656 414 [Full Text] [10.1086/510359] [Journal Article/Letter]

2007. "Neutron star oscillations and QPOs during magnetar flares." Advances in Space Research 40 1446 [Full Text] [10.1016/j.asr.2006.12.021] [Journal Article/Letter]

2006. "Calibration of the Rossi X-Ray Timing Explorer Proportional Counter Array." The Astrophysical Journal Supplement Series 163 401 [Full Text] [10.1086/500659] [Journal Article/Letter]

2006. "RXTE Observations of 1A 1744-361: Correlated Spectral and Timing Behavior." The Astrophysical Journal 652 603 [Full Text] [10.1086/507786] [Journal Article/Letter]

2006. "The Discovery of a Neutron Star with a Spin Frequency of 530 Hz in A1744-361." The Astrophysical Journal 639 L31 [Full Text] [10.1086/501438] [Journal Article/Letter]

2006. "Understanding high-density matter through analysis of surface spectral lines and burst oscillations from accreting neutron stars." Advances in Space Research 38 2765 [Full Text] [10.1016/j.asr.2005.10.049] [Journal Article/Letter]

2006. "Detection of the irradiated donor in the LMXBs 4U 1636-536 (=V801 Ara) and 4U 1735-444 (=V926 Sco)." Monthly Notices of the Royal Astronomical Society 373 1235 [Full Text] [10.1111/j.1365-2966.2006.11106.x] [Journal Article/Letter]

2006. "The energy dependence of burst oscillations from the accreting millisecond pulsar XTE J1814-338." Monthly Notices of the Royal Astronomical Society 373 769 [Full Text] [10.1111/j.1365-2966.2006.11072.x] [Journal Article/Letter]

2006. "The 2004 Hyperflare from SGR 1806-20: Further Evidence for Global Torsional Vibrations." The Astrophysical Journal 653 593 [Full Text] [10.1086/508703] [Journal Article/Letter]

2006. "Spreading of Thermonuclear Flames on the Neutron Star in SAX J18084-3658: An Observational Tool." The Astrophysical Journal 642 L161 [Full Text] [10.1086/504841] [Journal Article/Letter]

2006. "Signature of Temporary Burning Front Stalling from a Non-Photospheric Radius Expansion Double-peaked Burst." The Astrophysical Journal 641 L53 [Full Text] [10.1086/503768] [Journal Article/Letter]

2006. "Detection with RHESSI of High-Frequency X-Ray Oscillations in the Tailof the 2004 Hyperflare from SGR 1806-20." The Astrophysical Journal 637 L117 [Full Text] [10.1086/500735] [Journal Article/Letter]

2006. "A Non-PRE Double-peaked Burst from 4U 1636-536: Evidence of Burning Front Propagation." The Astrophysical Journal 636 L121 [Full Text] [10.1086/500199] [Journal Article/Letter]

2005. "Analysis of Variability in the Burst Oscillations of the Accreting Millisecond Pulsar XTE J1814-338." The Astrophysical Journal 634 547 [Full Text] [10.1086/496953] [Journal Article/Letter]

2005. "Discovery of the Accretion-powered Millisecond X-Ray Pulsar IGR J00291+5934." The Astrophysical Journal 622 L45 [Full Text] [10.1086/429563] [Journal Article/Letter]

2005. "Constraints on Neutron Star Parameters from Burst Oscillation Light Curves of the Accreting Millisecond Pulsar XTE J1814-338." The Astrophysical Journal 619 483 [Full Text] [10.1086/426383] [Journal Article/Letter]

2005. "Evidence for Harmonic Content and Frequency Evolution of Oscillations during the Rising Phase of X-Ray Bursts from 4U 1636-536." The Astrophysical Journal 634 L157 [Full Text] [10.1086/499100] [Journal Article/Letter]

2005. "Discovery of Fast X-Ray Oscillations during the 1998 Giant Flare from SGR 1900+14." The Astrophysical Journal 632 L111 [Full Text] [10.1086/497911] [Journal Article/Letter]

2005. "Light curves of oscillating neutron stars." Monthly Notices of the Royal Astronomical Society 361 659 [Full Text] [10.1111/j.1365-2966.2005.09198.x] [Journal Article/Letter]

2005. "Precision X-Ray Timing of RX J08063+1527 with Chandra: Evidence for Gravitational Radiation from an Ultracompact Binary." The Astrophysical Journal 627 920 [Full Text] [10.1086/430439] [Journal Article/Letter]

2004. "Discovery of the Neutron Star Spin Frequency in EXO 0748-676." The Astrophysical Journal 614 L121 [Full Text] [10.1086/425737] [Journal Article/Letter]

2004. "Chandra Detection of the AM Canum Venaticorum Binary ES Ceti (KUV 01584-0939)." The Astrophysical Journal 614 358 [Full Text] [10.1086/423615] [Journal Article/Letter]

2004. "Chandra Observations of V407 Vulpeculae: Confirmation of the Spin-up." The Astrophysical Journal 610 416 [Full Text] [10.1086/421384] [Journal Article/Letter]

2004. "Detection of Nitrogen and Neon in the X-Ray Spectrum of GP Comae Berenices with XMM/Newton." The Astrophysical Journal 608 L53 [Full Text] [10.1086/422192] [Journal Article/Letter]

2004. "The Evolution of the Accretion Disk around 4U 1820-30 during a Superburst." The Astrophysical Journal 602 L105 [Full Text] [10.1086/382703] [Journal Article/Letter]

2003. "X-Ray Bursts from the Accreting Millisecond Pulsar XTE J1814-338." The Astrophysical Journal 596 L67 [Full Text] [10.1086/379158] [Journal Article/Letter]

2003. "A peculiar type-I X-ray burst from GRS 1747-312." Astronomy and Astrophysics, v409, p659-663 (2003) 409 659 [Full Text] [10.1051/0004-6361:20031042] [Journal Article/Letter]

2003. "Bursts, eclipses, dips and a refined position for the luminous low-mass X-ray binary in the globular cluster Terzan 6." Astronomy and Astrophysics, v406, p233-243 (2003) 406 233 [Full Text] [10.1051/0004-6361:20030681] [Journal Article/Letter]

2003. "Phase Coherent Timing of RX J08063+1527 with ROSAT and Chandra." The Astrophysical Journal 593 L39 [Full Text] [10.1086/378061] [Journal Article/Letter]

2003. "Discovery of X-Ray Quasi-periodic Oscillations from an Ultraluminous X-Ray Source in M82: Evidence against Beaming." The Astrophysical Journal 586 L61 [Full Text] [10.1086/374732] [Journal Article/Letter]

2002. "Discovery of a Second Millisecond Accreting Pulsar: XTE J1751-305." The Astrophysical Journal 575 L21 [Full Text] [10.1086/342612] [Journal Article/Letter]

2002. "Evidence for a Millisecond Pulsar in 4U 1636-53 during a Superburst." The Astrophysical Journal 577 337 [Full Text] [10.1086/342152] [Journal Article/Letter]

2002. "Bounds on Compactness for Low-Mass X-Ray Binary Neutron Stars from X-Ray Burst Oscillations." The Astrophysical Journal 564 353 [Full Text] [10.1086/324132] [Journal Article/Letter]

2002. "Evidence for Orbital Decay of RX J19144+2456: Gravitational Radiation and the Nature of the X-Ray Emission." The Astrophysical Journal 581 577 [Full Text] [10.1086/344101] [Journal Article/Letter]

2002. "Gravitational waves from rotating neutron stars and evaluation of fast chirp transform techniques." Classical and Quantum Gravity 19 1321 [Full Text] [10.1088/0264-9381/19/7/313] [Journal Article/Letter]

2002. "Burst Oscillation Periods from 4U 1636-53: A Constraint on the Binary Doppler Modulation." The Astrophysical Journal 568 279 [Full Text] [10.1086/338890] [Journal Article/Letter]

2002. "The Burst Behavior of the Eclipsing Low-Mass X-Ray Binary MXB 1659-298." The Astrophysical Journal 566 1060 [Full Text] [10.1086/338140] [Journal Article/Letter]

2002. "A Remarkable 3 Hour Thermonuclear Burst from 4U 1820-30." The Astrophysical Journal 566 1045 [Full Text] [10.1086/338337] [Journal Article/Letter]

2001. "An Unusual Burst from Soft Gamma Repeater SGR 1900+14: Comparisons with Giant Flares and Implications for the Magnetar Model." The Astrophysical Journal 558 237 [Full Text] [10.1086/322248] [Journal Article/Letter]

2001. "Oscillations during thermonuclear X-ray bursts: A new probe of neutron stars." X-RAY ASTRONOMY: Stellar Endpoints,AGN, and the Diffuse X-ray Background Edited by Nicholas E White, Giuseppe Malaguti, and Giorgio GC Palumbo Melville, NY: American Institute of Physics, 2001 AIP Conference Proceedings 599 377 [Full Text] [10.1063/1.1434650] [Journal Article/Letter]

2001. "The steady spin-down rate of 4U 1907+09." Monthly Notices of the Royal Astronomical Society 327 1269 [Full Text] [10.1046/j.1365-8711.2001.04804.x] [Journal Article/Letter]

2001. "Discovery of a Second High-Frequency Quasi-periodic Oscillation from the Microquasar GRS 1915+105." The Astrophysical Journal 554 L169 [Full Text] [10.1086/321720] [Journal Article/Letter]

2001. "Discovery of a 450 HZ Quasi-periodic Oscillation from the Microquasar GRO J1655-40 with the Rossi X-Ray Timing Explorer." The Astrophysical Journal 552 L49 [Full Text] [10.1086/320258] [Journal Article/Letter]

2001. "Discovery of Nearly Coherent Oscillations with a Frequency of ~567 HZ during Type I X-Ray Bursts of the X-Ray Transient and Eclipsing Binary X1658-298." The Astrophysical Journal 549 L71 [Full Text] [10.1086/319128] [Journal Article/Letter]

2001. "Oscillations during thermonuclear x-ray bursts." Advances in Space Research 28 511 [Full Text] [10.1016/S0273-1177(01)00422-7] [Journal Article/Letter]

2000. "Differences between the two anomalous X-ray pulsars: variations in the spin-down rate of 1E 10481-5937 and an extended interval of quiet spin-down in 1E 2259+586." Monthly Notices of the Royal Astronomical Society 319 205 [Full Text] [10.1046/j.1365-8711.2000.03845.x] [Journal Article/Letter]

2000. "Timing Noise in SGR 1806-20." The Astrophysical Journal 535 L55 [Full Text] [10.1086/312698] [Journal Article/Letter]

2000. "The orbital period of the recurrent X-ray transient in Terzan 6." Astronomy and Astrophysics, v355, p145-154 (2000) 355 145 [Full Text] [Journal Article/Letter]

2000. "Discovery of a 64 KEV Emission Line in a Burst from SGR 1900+14." The Astrophysical Journal 537 L111 [Full Text] [10.1086/312769] [Journal Article/Letter]

2000. "Post-glitch RXTE-PCA observations of the Vela pulsar." Astronomy and Astrophysics, v356, p1136-1140 (2000) 356 1136 [Full Text] [Journal Article/Letter]

1998. "On the Amplitude of Burst Oscillations in 4U 1636-54: Evidence for Nuclear-powered Pulsars." ApJ 498 L135 [10.1086/311322] [Journal Article/Letter]

1996. "Kilohertz X-ray variability from an accreting neutron star system." ApJL 469 L9. [Journal Article/Letter]