تقرير
Evidence for quiescent synchrotron emission in the black hole X-ray transient Swift J1357.2-0933
| العنوان: | Evidence for quiescent synchrotron emission in the black hole X-ray transient Swift J1357.2-0933 |
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| المؤلفون: | Shahbaz, T., Russell, D. M., Zurita, C., Casares, J., Corral-Santana, J. M., Dhillon, V. S., Marsh, T. R. |
| سنة النشر: | 2013 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics - High Energy Astrophysical Phenomena |
| الوصف: | We present high time-resolution ULTRACAM optical and NOTCam infrared observations of the edge-on black hole X-ray transient Swift J1357.2-0933. Our data taken in 2012 and 2013 show the system to be at its pre-outburst magnitude and so the system is in quiescence. In contrast to other X-ray transients, the quiescent light curves of Swift J1357.2-0933 do not show the secondary star's ellipsoidal modulation. The optical light curve is dominated by variability with an optical fractional rms of ~35 per cent, a factor of >3 larger than what is observed in other systems at similar time-resolution. Optical flare events lasting 2-10min with amplitudes of up to ~1.5 mag are seen as well as numerous rapid ~0.8 mag dip events which are similar to the optical dips seen in outburst. Similarly the infrared J-band light curve is dominated by variability with a fractional rms of ~21 per cent and flare events lasting 10--30 min with amplitudes of up to ~1.5 mag are observed. The quiescent optical to mid-infrared spectral energy distribution in quiescence is dominated by a non-thermal component with a power--law index of -1.4, (the broad-band rms SED has a similar index) which arises from optically thin synchrotron emission most likely originating in a weak jet; the lack of a peak in the spectral energy distribution rules out advection-dominated models. Using the outburst amplitude--period relation for X-ray transients we estimate the quiescent magnitude of the secondary star to lie in the range V_min=22.7 to 25.6, which when combined with the absolute magnitude of the expected M4.5 V secondary star allows us to constrain to the distance to lie in the range 0.5 to 6.3 kpc. (Abridged) Comment: 12 pages, 7 figures, 2 tables, accepted for publication in MNRAS |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1093/mnras/stt1212 |
| URL الوصول: | http://arxiv.org/abs/1307.0659 |
| رقم الأكسشن: | edsarx.1307.0659 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1093/mnras/stt1212 |
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