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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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2017-01-01
Tetarenko, Alexandra Jean, Sivakoff, Gregory Robert, Miller-Jones, James C. A., Rosolowsky, E. W., Petitpas, G., Gurwell, M., Wouterloot, J., Fender, Rob P., Heinz, S., Maitra, D., Markoff, Sera B., Migliari, Simone, Rupen, Michael P., Rushton, Anthony P., Russell, D. M., Russell, Thomas D., Sarazin, Craig L.
We present simultaneous radio through sub-mm observations of the black hole X-ray binary (BHXB) V404 Cygni during the most active phase of its June 2015 outburst. Our 4 h long set of overlapping observations with the Very Large Array, the Sub-millimeter Array and the James Clerk Maxwell Telescope...
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Extreme quiescent variability of the transient neutron star low-mass X-ray binary EXO 1745-248 in Terzan 5
Download2018-01-01
Rivera Sandoval, L. E., Wijnands, Rudy, Denegaar, Nathalie, Cavecchi, Y., Heinke, Craig O., Cackett, Edward M., Homan, Jeroen, Altamirano, Diego, Bahramian, Arash, Sivakoff, Gregory Robert, Miller, Jon M., Parikh, Aastha S.
EXO 1745−248 is a transient neutron star low-mass X-ray binary that resides in the globular cluster Terzan 5. We studied the transient during its quiescent state using 18 Chandra observations of the cluster acquired between 2003 and 2016. We found an extremely variable source, with a luminosity...
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2009-01-01
Croston, Judith H., Kraft, Ralph P., Hardcastle, Martin J., Birkinshaw, Mark, Worrall, Diana M., Nulsen, P. E. J., Penna, R. F., Sivakoff, Gregory Robert, Jordán, Andrés, Brassington, Nicola J., Evans, Daniel A., Forman, William R., Gilfanov, Marat, Goodger, Joanna L., Harris, Wayne E., Jones, Christine, Juett, Adrienne M., Murray, Stephen S., Raychaudhury, Somak, Sarazin, Craig L., Voss, Rasmus, Woodley, Kristin A.
We present new results on the shock around the south-west radio lobe of Centaurus A using data from the Chandra Very Large Programme observations (740 ks total observing time). The X-ray spectrum of the emission around the outer south-western edge of the lobe is well described by a single...
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2018-01-01
Tudor, Vlad, Miller-Jones, James C. A., Knigge, C., Maccarone, Thomas J., Tauris, T. M., Bahramian, Arash, Chomiuk, Laura, Heinke, Craig O., Sivakoff, Gregory Robert, Strader, Jay, Plotkin, Richard M., Soria, Roberto, Albrow, M. D., Anderson, G. E., van den Berg, Maureen, Bernardini, Federico, Bogdanov, Slavko, Britt, Christopher. T., Russell, D. M., Zurek, David R.
To confirm the nature of the donor star in the ultracompact X-ray binary candidate 47 Tuc X9, we obtained optical spectra (3000–10 000 Å) with the Hubble Space Telescope / Space Telescope Imaging Spectrograph. We find no strong emission or absorption features in the spectrum of X9. In particular,...
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2015-01-01
Corbel, Stephane, Miller-Jones, James C. A., Fender, Rob P., Gallo, Elena, Maccarone, Thomas J., O'Brien, Tim, Paragi, Zsolt, Rupen, Michael P., Rushton, Anthony, Sabatini, Sabina, Sivakoff, Gregory Robert, Strader, Jay, Woudt, Patrick Alan
The universal link between the processes of accretion and ejection leads to the formation of jets and outflows around accreting compact objects. Incoherent synchrotron emission from these outflows can be observed from a wide range of accreting binaries, including black holes, neutron stars, and...
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Lord of the Rings - Return of the King: Swift-XRT observations of dust scattering rings around V404 Cygni
Download2016-01-01
Beardmore, A. P., Willingale, R., Kuulkers, E., Altamirano, Diego, Motta, S. E., Osborne, J. P., Page, Kim L., Sivakoff, Gregory Robert
On 2015 June 15, the black hole X-ray binary V404 Cygni went into outburst, exhibiting extreme X-ray variability which culminated in a final flare on June 26. Over the following days, the Swift-X-ray Telescope detected a series of bright rings, comprising five main components that expanded and...
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2011-01-01
Zhang, Zhongli, Gilfanov, Marat, Voss, Rasmus, Sivakoff, Gregory Robert, Kraft, Ralph P., Brassington, Nicola J., Kundu, Arunav, Jordán, Andrés Jordán, Sarazin, Craig, L.
Aims. Based on the archival data from the Chandra observations of nearby galaxies, we study different sub populations of low-mass X-ray binaries (LMXBs) – dynamically formed systems in globular clusters (GCs) and in the nucleus of M 31 and (presumably primordial) X-ray binaries in the fields of...
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2018-01-01
Tetarenko, Alexandra Jean, Freeman, P., Rosolowsky, E. W., Miller-Jones, James C. A., Sivakoff, Gregory Robert
We present Atacama Large Millimetre/Sub-Millimetre Array (ALMA) observations of IRAS 19132+1035, a candidate jet–interstellar medium (ISM) interaction zone near the black hole X-ray binary (BHXB) GRS 1915+105. With these ALMA observations (combining data from the 12 m array and the Atacama...
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2018-01-01
Shaw, A. W., Heinke, Craig O., Mukai, K., Sivakoff, Gregory Robert, Tomsick, John A., Rana, Vikram
The X-ray spectra of intermediate polars can be modelled to give a direct measurement of white dwarf mass. Here, we fit accretion column models to NuSTAR spectra of three intermediate polars; V709 Cas, NY Lup, and V1223 Sgr in order to determine their masses. From fits to 3–78 keV spectra, we...
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2015-01-01
Degenaar, Nathalie, Wijnands, Rudy, Bahramian, Arash, Sivakoff, Gregory Robert, Heinke, Craig O., Brown, E. F., Fridriksson, Joel K., Homan, Jeroen, Cackett, Edward M., Cumming, A., Miller, Jon M., Altamirano, Diego, Pooley, David
When neutron stars reside in transient X-ray binaries, their crustal layers become heated during accretion outbursts and subsequently cool in quiescence. Observing and modelling this thermal response has yielded valuable insight into the physics of neutron star crusts. However, one unresolved...