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Skip to Search Results- 32Sivakoff, Gregory Robert
- 13Altamirano, Diego
- 13Miller-Jones, James C. A.
- 12Heinke, Craig O.
- 10Fender, Rob P.
- 9Russell, D. M.
- 23X-Rays: Binaries
- 11Accretion
- 11Radio Continuum: Stars
- 10Accretion Discs
- 8Ism: Jets And Outflows
- 7Stars: Neutron
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2014-01-01
Forestell, Lindsay M., Heinke, Craig O., Cohn, Haldan N., Lugger, P. M., Sivakoff, Gregory Robert, Bogdanov, Slavko, Cool, A. M., Anderson, J.
We combine new and archival Chandra observations of the globular cluster NGC 6752 to create a deeper X-ray source list, and study the faint radio millisecond pulsars (MSPs) of this cluster. We detect four of the five MSPs in NGC 6752, and present evidence for emission from the fifth. The X-rays...
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2017-01-01
Joseph, Tana D., Maccarone, Thomas J., Kraft, Ralph P., Sivakoff, Gregory Robert
In this paper we discuss the X-ray point source population of NGC 4472, an elliptical galaxy in the Virgo cluster. We used recent deep Chandra data combined with archival Chandra data to obtain a 380 ks exposure time. We find 238 X-ray point sources within 3.7 arcmin of the galaxy centre, with a...
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2012-01-01
Altamirano, Diego, Keek, L., Cumming, A., Sivakoff, Gregory Robert, Heinke, Craig O., Wijnands, Rudy, Degenaar, Nathalie, Homan, Jeroen, Pooley, David
We report on Chandra, Rossi X-ray Timing Explorer (RXTE), Swift/Burst Alert Telescope (BAT) and MAXI observations of an X-ray flare of ∼1 d and subsequent outburst of a transient X-ray source observed in 2011 October–November in the globular cluster Terzan 5. We show that the source is the same...
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Deep Chandra observations of the NGC 4472 globular cluster black hole XMMU 1229397+075333: short-term variability from the first globular cluster black hole binary
Download2015-01-01
Joseph, Tana D., Maccarone, Thomas J., Kraft, Ralph P., Sivakoff, Gregory Robert
In this paper, we discuss the luminosity modulations and spectral analysis results of the recent deep observations of XMMU 122939.7+075333, the first black hole discovered in a globular cluster. The source has been detected many times, typically with LX > 1039 erg s−1, but in a 2010 observation...
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Deep radio imaging of 47 Tuc identifies the peculiar X-ray source X9 as a new black hole candidate
Download2015-01-01
Miller-Jones, James C. A., Strader, Jay, Heinke, Craig O., Maccarone, Thomas J., van den Berg, Maureen, Knigge, C., Chomiuk, Laura, Noyola, Eva, Russell, Thomas D., Seth, Anil C., Sivakoff, Gregory Robert
We report the detection of steady radio emission from the known X-ray source X9 in the globular cluster 47 Tuc. With a double-peaked C IV emission line in its ultraviolet spectrum providing a clear signature of accretion, this source had been previously classified as a cataclysmic variable. In...
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2012-01-01
Miller-Jones, James. C. A., Sivakoff, Gregory Robert, Altamirano, Diego, Coriat, Mickael, Corbel, Stephane, Dhawan, Vasudha, Krimm, H. A., Remillard, Ronald Alan, Rupen, Michael. P., Russell, D. M., Fender, Rob P., Heinz, S., Körding, Elmar. G., Maitra, D., Markoff, Sera, Migliari, Simone, Sarazin, Craig. L., Tudose, Valeriu
We present an intensive radio and X-ray monitoring campaign on the 2009 outburst of the Galactic black hole candidate X-ray binary H1743−322. With the high angular resolution of the Very Long Baseline Array, we resolve the jet ejection event and measure the proper motions of the jet ejecta...
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2016-01-01
Bahramian, Arash, Sivakoff, Gregory Robert, Tremou, Evangelia, Linares, Manuel, Tudor, Vlad, Miller-Jones, James. C. A., Heinke, Craig O., Chomiuk, Laura, Strader, Jay, Altamirano, Diego, Degenaar, Nathalie, Maccarone, Thomas J., Patruno, A., Sanna, Andrea, Wijnands, Rudy, Tetarenko, Alexandra Jean
We present the results of Very Large Array, Australia Telescope Compact Array, and Swift X-ray Telescope observations of the 2015 outburst of the transient neutron star X-ray binary (NSXB), EXO 1745−248, located in the globular cluster Terzan 5. Combining (near-) simultaneous radio and X-ray...
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2018-01-01
Sanna, Andrea, Bahramian, Arash, Bozzo, E., Heinke, Craig O., Wijnands, Rudy, Degenaar, Nathalie, Maccarone, T., Riggio, Alessandro, Di Salvo, Tiziana, Iaria, Rosario, Burgay, M., Possenti, Andrea, Ferrigno, C., Papitto, A., Sivakoff, Gregory Robert, D'Amico, Nicolo, Burderi, Luciano, Altamirano, Diego
We report the discovery of X-ray pulsations at 105.2 Hz (9.5 ms) from the transient X-ray binary IGR J16597–3704 using NuSTAR and Swift. The source was discovered by INTEGRAL in the globular cluster NGC 6256 at a distance of 9.1 kpc. The X-ray pulsations show a clear Doppler modulation that...
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2016-01-01
Coppejans, Deanne L., Körding, Elmar G., Miller-Jones, James. C. A., Rupen, Michael P., Sivakoff, Gregory Robert, Knigge, C., Groot, Paul J., Woudt, Patrick Alan, Waagen, Elizabeth O., Templeton, Matthew
We present 8–12 GHz radio light curves of five dwarf nova (DN) type cataclysmic variable stars (CVs) in outburst (RX And, U Gem, and Z Cam), or superoutburst (SU UMa and YZ Cnc), increasing the number of radio-detected DN by a factor of 2. The observed radio emission was variable on time-scales...
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2016-01-01
Bahramian, Arash, Tetarenko, Alexandra Jean, Sivakoff, Gregory Robert, Tremou, Evangelia, Linares, Manuel, Tudor, Vlad, Miller-Jones, James C. A., Heinke, Craig O., Chomiuk, Laura, Strader, Jay, Altamirano, Diego, Degenaar, Nathalie, Maccarone, Thomas J., Patruno, A., Sanna, Andrea, Wijnands, Rudy
The paper “Disc-Jet Coupling in the Terzan 5 Neutron Star X-ray Binary EXO 1745−248” was published as Tetarenko et al. 2016, MNRAS, 460, 345–355. In Section 3.3 of the paper there is a minor error in equation (1). The correct equation is as follows, (logLR−logLR,c)=logξ+β(logLX−logLX,c). (1) The...