X‐Ray States and Radio Emission in the Black Hole Candidate XTE J1550−564
Open Access
- 10 June 2001
- journal article
- research article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 554 (1), 43-48
- https://doi.org/10.1086/321364
Abstract
We report on radio and X-ray observations of the black hole candidate (BHC) XTE J1550-564 performed during its 2000 X-ray outburst. Observations were conducted with the Australia Telescope Compact Array and allowed us to sample the radio behavior of XTE J1550-564 in the X-ray low hard and intermediate/very high states. We observed optically thin radio emission from XTE J1550-564 5 days after a transition to an intermediate/very high state, but we observed no radio emission 6 days later, while XTE J1550-564 was still in the intermediate/very high state. In the low hard state, XTE J1550-564 is detected with an inverted radio spectrum. The radio emission in the low hard state most likely originates from a compact jet; optical observations suggest that the synchrotron emission from this jet may extend up to the optical range. The total power of the compact jet might therefore be a significant fraction of the total luminosity of the system. We suggest that the optically thin radio emission detected 5 days after the transition to the intermediate/very high state is due to a discrete ejection of relativistic plasma during the state transition. Subsequent to the decay of the optically thin radio emission associated with the state transition, it seems that in the intermediate/very high state the radio emission is quenched by a factor greater than 50, implying a suppression of the outflow. We discuss the properties of radio emission in the X-ray states of BHCs.This publication has 32 references indexed in Scilit:
- The 1997 hard-state outburst of the X-ray transient GS 1354-64/BW CirMonthly Notices of the Royal Astronomical Society, 2001
- Spectral evidence for a powerful compact jet from XTE J1118+480Monthly Notices of the Royal Astronomical Society, 2001
- Powerful jets from black hole X-ray binaries in low/hard X-ray statesMonthly Notices of the Royal Astronomical Society, 2001
- Orbital, precessional and flaring variability of Cygnus X-1Monthly Notices of the Royal Astronomical Society, 1999
- Quenching of the Radio Jet during the X-Ray High State of GX 339−4The Astrophysical Journal, 1999
- A State Transition of GX 339−4 Observed with the [ITAL]Rossi X-Ray Timing Explorer[/ITAL]The Astrophysical Journal, 1999
- Magnetic flares in accretion disc coronae and the spectral states of black hole candidates: the case of GX339-4Monthly Notices of the Royal Astronomical Society, 1999
- Strong Aperiodic X-Ray Variability and Quasi-Periodic Oscillationin X-Ray Nova XTE J1550−564The Astrophysical Journal, 1999
- Plasma Ejection from Magnetic Flares and the X-Ray Spectrum of Cygnus X-1The Astrophysical Journal, 1999
- Dynamical evidence for a black hole in the eclipsing X-ray nova GRO J1655 – 40Nature, 1995