Michael P. Muno

Near-Infrared Counterparts to Chandra X-ray Sources toward the Galactic Center. I. Statistics and a Catalog of Candidates (2009)

Mauerhan, Jon C., Muno, Michael P., Morris, Mark R., Bauer, Franz E., Nishiyama, Shogo, Nagata, Tetsuya

We present a catalog of 5184 candidate infrared counterparts to X-ray sources detected towards the Galactic center. The X-ray sample contains 9017 point sources detected in this region by the Chandra...

Discovery and interpretation of an X-ray period in the galactic center source CXOGC J174536.1–285638 (2008)

Mikles, Valerie J., Eikenberry, Stephen S., Bandyopadhyay, Reba M., Muno, Michael P.

We present X-ray and infrared observations of the X-ray source CXOGC J174536.1-285638. Previous observations suggest that this source may be an accreting binary with a high-mass donor (HMXB) or a...

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...

Exploring a New Population of Compact Objects: X-ray and IR Observations of the Galactic Centre (2008)

Bandyopadhyay, Reba M., Gosling, Andrew J., Eikenberry, Stephen E., Muno, Michael P., Blundell, Katherine M., Podsiadlowski, Philipp, ...

I describe the IR and X-ray observational campaign we have undertaken for the purpose of determining the nature of the faint discrete X-ray source population discovered by Chandra in the Galactic...

Exploring a New Population of Compact Objects: X-ray and IR Observations of the Galactic Centre (2008)

Bandyopadhyay, Reba M., Gosling, Andrew J., Eikenberry, Stephen E., Muno, Michael P., Blundell, Katherine M., Podsiadlowski, Philipp, ...

I describe the IR and X-ray observational campaign we have undertaken for the purpose of determining the nature of the faint discrete X-ray source population discovered by Chandra in the Galactic...

Discovery and Interpretation of an X-ray Period in the Galactic Center Source CXOGC J174536.1-285638 (2008)

Mikles, Valerie J., Eikenberry, Stephen S., Bandyopadhyay, Reba M., Muno, Michael P.

We present X-ray and infrared observations of the X-ray source CXOGC J174536.1-285638. Previous observations suggest that this source may be an accreting binary with a high-mass donor (HMXB) or a...

Cataclysmic variables in globular clusters, the galactic center, and local space (2008)

Heinke, Craig O., Ruiter, Ashley J., Muno, Michael P., Belczynski, Krzysztof

We compare the X-ray spectra and luminosities, in the 2-8 keV band, of known and suspected cataclysmic variables (CVs) in different environments, assessing the nature of thesesource populations....

The path to buried treasure : paving the way to the FLAMINGOS-2 galactic center survey with IR and X-ray observations (2008)

Bandyopadhyay, Reba M., Eikenberry, Stephen S., Dewitt, Curtis, Gosling, Andrew J., Muno, Michael P.

I describe the IR and X-ray campaign we have undertaken to determine the nature of the faint discrete X-ray source population discovered by Chandra in the Galactic Center. These results will provide...

Discovery and interpretation of an X-ray period in the galactic center source CXOGC J174536.1-285638 (2008)

Mikles, Valerie J., Eikenberry, Stephen S., Muno, Michael P., Bandyopadhyay, Reba M.

We present X-ray and infrared observations of the X-ray source CXOGC J174536.1-285638 (hereafter, Edd-1). The spectrum of the X-ray source has a very prominent Fe 6.7 keV emission feature and the...

Massive stellar X-ray sources in the galactic center (2008)

Mauerhan, Jon C., Muno, Michael P., Bauer, Franz E., Morris, Mark R.

We present results of a spectroscopic survey of bright near-infrared counterparts to X-ray point sources from a deep Chandra survey of the Galactic nuclear bulge. K-band spectroscopy has revealed 13...

The Path to Buried Treasure: Paving the Way to the FLAMINGOS-2 Galactic Center Survey with IR and X-ray Observations (2008)

Bandyopadhyay, Reba M., Eikenberry, Stephen S., Dewitt, Curtis, Gosling, Andrew J., Muno, Michael P.

I describe the IR and X-ray campaign we have undertaken to determine the nature of the faint discrete X-ray source population discovered by Chandra in the Galactic Center. These results will provide...

Cataclysmic Variables in Globular Clusters, the Galactic Center, and Local Space (2008)

Heinke, Craig O., Ruiter, Ashley J., Muno, Michael P., Belczynski, Krzysztof

We compare the X-ray spectra and luminosities, in the 2-8 keV band, of known and suspected cataclysmic variables (CVs) in different environments, assessing the nature of these source populations....

Which Stars Form Black Holes and Neutron Stars? (2007)

Muno, Michael P.

I describe the current state of our knowledge of the mapping between the initial masses of stars and the compact objects — particularly neutron stars and black holes — that they produce. Most of...

Discovery of hot supergiant stars near the galactic center (2007)

Mauerhan, Jon C., Muno, Michael P., Morris, Mark

We report new results of a campaign to find Wolf-Rayet and O (WR/O) stars and high-mass X-ray binaries (HMXBs) in the Galactic center. We searched for candidates by cross-correlating the Two Micron...

Discovery of hot supergiant stars near the Galactic center (2007)

Mauerhan, Jon C., Muno, Michael P., Morris, Mark

We report new results of a campaign to find Wolf-Rayet and O (WR/O) stars and high-mass X-ray binaries (HMXBs) in the Galactic center. We searched for candidates by cross-correlating the 2MASS...

Which Stars Form Black Holes and Neutron Stars? (2006)

Muno, Michael P.

I describe the current state of our knowledge of the mapping between the initial masses of stars and the compact objects -- particularly neutron stars and black holes -- that they produce. Most of...

Mid-infrared emission from dust around quiescent low-mass X-ray binaries (2006)

Muno, Michael P., Mauerhan, Jon

We report the discovery of excess 4.5 and 8 μm emission from three quiescent black hole low-mass X-ray binaries, A0620−00, GS 2023+338, and XTE J1118+480, and the lack of similar excess emission...

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...

Diffuse, Non-Thermal X-ray Emission from the Galactic Star Cluster Westerlund 1 (2006)

Muno, Michael P., Law, Casey, Clark, J. Simon, Dougherty, Sean M., De Grijs, Richard, Zwart, Simon Portegies, ...

We present the diffuse X-ray emission identified in Chandra observations of the young, massive Galactic star cluster Westerlund 1. After removing point-like X-ray sources down to a completeness limit...

Eddington-limited X-ray Bursts as Distance Indicators. II. Possible Compositional Effects in Bursts from 4U 1636-536 (2005)

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...

A Candidate Neutron Star Associated with Galactic Center Supernova Remnant Sagittarius A East (2005)

Park, Sangwook, Muno, Michael P., Baganoff, Frederick K., Maeda, Yoshitomo, Morris, Mark, Chartas, George, ...

We present imaging and spectral studies of the supernova remnant (SNR) Sagittarius (Sgr) A East from deep observations with the {\it Chandra X-Ray Observatory}. The spatially-resolved spectral...

A Lack of Radio Emission from Neutron Star Low Mass X-ray Binaries (2004)

Muno, Michael P., Belloni, Tomaso, Dhawan, Vivek, Morgan, Edward H., Remillard, Ronald A., Rupen, Michael P.

We report strict upper limits to the radio luminosities of three neutron star low-mass X-ray binaries obtained with the Very Large Array while they were in hard X-ray states as observed with the...

Millisecond Oscillations During Thermonuclear X-ray Bursts (2004)

Muno, Michael P.

I review the basic phenomenology and theory of the millisecond brightness oscillations observed during thermonuclear X-ray bursts from 13 of approximately 70 accreting neutron stars in low-mass X-ray...

Characteristics of Diffuse X-Ray Line Emission within 20 pc of the Galactic Center (2003)

Park, Sangwook, Muno, Michael P., Baganoff, Frederick K., Maeda, Yoshitomo, Morris, Mark, Howard, Christian, ...

Over the last 3 yrs, the Galactic center (GC) region has been monitored with the Chandra X-Ray Observatory. With 11 Chandra observations through 2002 June, the total effective exposure reaches ~590...

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...

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...

Eddington-limited X-ray Bursts as Distance Indicators. I. Systematic Trends and Spherical Symmetry in Bursts from 4U 1728-34 (2002)

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...

X-ray QPOs in Black-Hole Binary Systems (2002)

Remillard, Ronald A., Muno, Michael P., McClintock, Jeffrey E., Orosz, Jerome A.

We briefly review the properties and physical consequences of quasiperiodic oscillations (QPOs) seen on many occasions in the X-ray emission from black-hole binary systems. We also report on the...

The Amplitude Evolution and Harmonic Content of Millisecond Oscillations in Thermonuclear X-ray Bursts (2002)

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...

Evidence for Harmonic Relationships in the High Frequency QPOs of XTE J1550-564 and GRO J1655-40 (2002)

Remillard, Ronald A., Muno, Michael P., McClintock, Jeffrey E., Orosz, Jerome A.

We continue to investigate the X-ray timing and spectral properties of the black hole binary, XTE J1550-564. For three different groups of observations, we show evidence that two high-frequency QPOs...

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...

Modeling the low-state spectrum of the X-Ray nova XTE J1118+480 (2001)

Esin, Ann A., McClintock, Jeffrey E., Drake, Jeremy J., Garcia, Michael R., Haswell, Carole A., Hynes, Robert I., ...

Based on recent multiwavelength observations of the new X-ray nova XTE J1118+480, we can place strong constraints on the geometry of the accretion flow in which a low/hard-state spectrum,...

Characterizing the QPO Behavior of the X-ray Nova XTE J1550--564 (2001)

Remillard, Ronald A., Sobczak, Gregory J., Muno, Michael P., McClintock, Jeffrey E.

For all 209 RXTE observations of the X-ray nova XTE J1550-564 during its major outburst of 1998-1999, we have analyzed the X-ray power spectra, phase lags, and coherence functions. The phase lags and...

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...

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...

Characterizing the Low-Frequency QPO behavior of the X-ray Nova XTE J1550-564 (2000)

Sobczak, Gregory J., Remillard, Ronald A., Muno, Michael P., McClintock, Jeffrey E.

For all 209 RXTE observations of the 7-Crab X-ray nova XTE J1550-564, we analyzed the X-ray power spectra, phase lags, and coherence functions. These observations cover the entire 250 day outburst...

Nearly Coherent Oscillations in Type I X-Ray Bursts from KS 1731-260 (2000)

Muno, Michael P., Fox, Derek W., Morgan, Edward H., Bildsten, Lars

We present an analysis of the nine type I X-ray bursts that were observed from KS 1731-260 with RXTE. We find that the bursts divide naturally into two populations: ``fast bursts'' occur on the...

QPOs and Spectral States in GRS 1915+105 (1999)

Muno, Michael P., Morgan, Edward H., Remillard, Ronald A.

We present results from the analysis of X-ray energy spectra and quasi- periodic oscillations (QPOs) from a set of observations which samples a broad range of time variability in GRS 1915+105. We...