SIMBAD references

2021A&A...650A..69C - Astronomy and Astrophysics, volume 650A, 69-69 (2021/6-1)

Multi-band observations of Swift J0840.7-3516: A new transient ultra-compact X-ray binary candidate.

COTI ZELATI F., DE UGARTE POSTIGO A., RUSSELL T.D., BORGHESE A., REA N., ESPOSITO P., ISRAEL G.L. and CAMPANA S.

Abstract (from CDS):

We report on multi-band observations of the transient source Swift J0840.7-3516, which was detected in outburst in 2020 February by the Neil Gehrels Swift Observatory. The outburst episode lasted just ∼5 days, during which the X-ray luminosity quickly decreased from LX≃3x1037d102erg/s at peak down to LX≃5x1033d102erg/s in quiescence (0.3-10keV; d10 is the distance to the source in units of 10kpc). Such a marked and rapid decrease in the flux was also registered at UV and optical wavelengths. In outburst, the source showed considerable aperiodic variability in the X-rays on timescales as short as a few seconds. The spectrum of the source in the energy range 0.3-20keV was well described by a thermal, blackbody-like, component plus a non-thermal, power law-like, component and it softened considerably as the source returned to quiescence. The spectrum of the optical counterpart in quiescence showed broad emission features mainly associated with ionised carbon and oxygen, superposed on a blue continuum. No evidence for bright continuum radio emission was found in quiescence. We discuss possible scenarios for the nature of this source and show that the observed phenomenology points to a transient ultra-compact X-ray binary system.

Abstract Copyright: © ESO 2021

Journal keyword(s): methods: data analysis - methods: observational - techniques: spectroscopic - X-rays: binaries - X-rays: individuals: Swift J0840.7-3516

Simbad objects: 11

goto Full paper

goto View the references in ADS

To bookmark this query, right click on this link: simbad:2021A&A...650A..69C and select 'bookmark this link' or equivalent in the popup menu


2021.11.28-22:47:00

© Université de Strasbourg/CNRS

    • Contact