The quiescent spectral energy distribution of V404 Cyg

Hynes, R. I.; Bradley, Charles K.; Rupen, M. P.; Gallo, Elena; Fender, R. P.; Casares, J.; Zurita, C.

doi:10.1111/j.1365-2966.2009.15419.x

Cited by 72 publications

(122 citation statements)

References 39 publications

Supporting

Mentioning

102

Contrasting

Order By: Relevance

“…An outer disk is likely present, but decomposing its emission from other radiative processes in quiescence likely requires an even better sampled SED with higher S/N , and/or high-resolution spectroscopy. For example, excess UV emission over the expected contribution from the companion star is often detected from quiescent BHXBs (see Hynes & Robinson 2012 and references therein; although also see Hynes et al 2009 who did not find a significant UV excess in the relatively luminous quiescent SED of V404 Cyg). Some of this UV excess is likely thermal radiation from the outer disk, as UV spectroscopy often reveals broad emission lines (including for both J1118 and A0620-00; McClintock et al 2003;Froning et al 2011).…”

Section: Discussionmentioning

confidence: 99%

“…Here, we focus on the spectral modeling of these data, and we discuss these data in the context of radio/X-ray luminosity correlations in a companion paper (Gallo et al 2014). In Section 2 we describe our observations and data reduction, where we add nearly simultaneous NIR, optical, and UV observations to the VLA radio and 2 We note that the SED of V404 Cyg has also been well sampled in quiescence (Hynes et al 2009), but its quiescent X-ray luminosity is approximately two orders of magnitude higher than A0620-00.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Constraints on relativistic jets in quiescent black hole X-ray binaries from broad-band spectral modelling

Plotkin

Gallo

Markoff

et al. 2014

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

The nature of black hole jets at the lowest detectable luminosities remains an open question, largely due to a dearth of observational constraints. Here, we present a new, nearly-simultaneous broadband spectrum of the black hole X-ray binary (BHXB) XTE J1118+480 at an extremely low Eddington ratio (L X ∼ 10 −8.5 L Edd ). Our new spectral energy distribution (SED) includes the radio, near-infrared, optical, ultraviolet, and X-ray wavebands. XTE J1118+480 is now the second BHXB at such a low Eddington ratio with a well-sampled SED, thereby providing new constraints on highly sub-Eddington accretion flows and jets, and opening the door to begin comparison studies between systems. We apply a multi-zone jet model to the new broadband SED, and we compare our results to previous fits to the same source using the same model at 4-5 decades higher luminosity. We find that after a BHXB transitions to the so-called quiescent spectral state, the jet base becomes more compact (by up to an order of magnitude) and slightly cooler (by at least a factor of two). Our preferred model fit indicates that jet particle acceleration is much weaker after the transition into quiescence. That is, accelerated non-thermal particles no longer reach high enough Lorentz factors to contribute significant amounts of synchrotron X-ray emission. Instead, the X-ray waveband is dominated by synchrotron self-Compton emission from a population of mildly relativistic electrons with a quasi-thermal velocity distribution that are associated with the jet base. The corresponding (thermal) synchrotron component from the jet base emits primarily in the infrared through ultraviolet wavebands. Our results on XTE J1118+480 are consistent with broadband modeling for A0620-00 (the only other comparably low Eddington ratio BHXB with a well-sampled SED) and for Sgr A* (the quiescent supermassive black hole at the Galactic center). The above could therefore represent a canonical baseline geometry for accreting black holes in quiescence. We conclude with suggestions for future studies to further investigate the above scenario.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Constraints on relativistic jets in quiescent black hole X-ray binaries from broad-band spectral modelling

Plotkin

Gallo

Markoff

et al. 2014

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

show abstract

“…It is worth noting though that distance uncertainties can not be modelled as uncorrelated errors, as they have the effect of shifting data points for a specific system along the LX∝Lr plane, rather than randomizing the measurements. All considered, 0.3 dex, or a factor ∼2 in luminosity seems to be a fair representation of the observed short-term radio and X-ray luminosity variability for hard and quiescent state black hole X-ray binaries (Garcia et al 2001;Gallo et al 2006;Gallo et al 2007;Hynes et al 2003aHynes et al , 2004Hynes et al , 2006Hynes et al , 2009Bradley et al 2007;Miller-Jones et al 2008;Bernardini & Cackett 2014; notice that σ 0.15 dex was adopted in previous works, e.g. Corbel et al 2013), and it also accounts for the uncertainties in the slope of the partially self-absorbed radio jet (often assumed as flat; please see § 5 for a quantitative discussion).…”

Section: Xte J1118+480 In the Radio/x-ray Domainmentioning

confidence: 99%

The radio/X-ray domain of black hole X-ray binaries at the lowest radio luminosities

Gallo¹,

Miller-Jones²,

Russell³

et al. 2014

Monthly Notices of the Royal Astronomical Society

Self Cite

153

200

View full text Add to dashboard Cite

We report on deep, coordinated radio and X-ray observations of the black hole X-ray binary XTE J1118+480 in quiescence. The source was observed with the Karl G. Jansky Very Large Array for a total of 17.5 hrs at 5.3 GHz, yielding a 4.8±1.4 µJy radio source at a position consistent with the binary system. At a distance of 1.7 kpc, this corresponds to an integrated radio luminosity between 4-8 ×10 25 erg s −1 , depending on the spectral index. This is the lowest radio luminosity measured for any accreting black hole to date. Simultaneous observations with the Chandra X-ray Telescope detected XTE J1118+480 at 1.2 × 10 −14 erg s −1 cm −2 (1-10 keV), corresponding to an Eddington ratio of ∼4 × 10 −9 for a 7.5 M black hole. Combining these new measurements with data from the 2005 and 2000 outbursts available in the literature, we find evidence for a relationship of the form r =α+β X (where denotes logarithmic luminosities), with β = 0.72 ± 0.09. XTE J1118+480 is thus the third system -together with GX339-4 and V404 Cyg -for which a tight, non-linear radio/X-ray correlation has been reported over more than 5 dex in X . Confirming previous results, we find no evidence for a dependence of the correlation normalisation of an individual system on orbital parameters, relativistic boosting, reported black hole spin and/or black hole mass. We then perform a clustering and linear regression analysis on what is arguably the most up-to-date collection of coordinated radio and X-ray luminosity measurements from quiescent and hard state black hole X-ray binaries, including 24 systems. At variance with previous results, a two-cluster description is statistically preferred only for random errors < ∼ 0.3 dex in both r and X , a level which we argue can be easily reached when the known spectral shape/distance uncertainties and intrinsic variability are accounted for. A linear regression analysis performed on the whole data set returns a best-fitting slope β = 0.61 ± 0.03 and intrinsic scatter σ 0 = 0.31 ± 0.03 dex.

show abstract

“…There are currently only three lowmass BHXB systems (with a confirmed black hole accretor) that have meaningful, simultaneous radio and X-ray constraints on their jets in quiescence, V404 Cyg (LX /L Edd ≈ 10 −6 ; Hjellming et al 2000;Gallo, Fender & Hynes 2005;Hynes et al 2009), A0620−00 (LX /L Edd ≈ 10 −8.5 ; Gallo et al 2006), and XTE J1118+480 (LX /L Edd ≈ 10 −8.5 ; Gallo et al 2014). The (high-mass) Be/black hole X-ray binary system MWC 656 also has non-simultaneous radio and X-ray detections in quiescence (LX /L Edd ≈ 10 −8 ; Munar-Adrover et al 2014;Dzib, Massi & Jaron 2015).…”

Section: Introductionmentioning

confidence: 99%

A clean sightline to quiescence: multiwavelength observations of the high Galactic latitude black hole X-ray binary Swift J1357.2−0933

Plotkin

Gallo

Jonker

et al. 2015

Mon. Not. R. Astron. Soc.

View full text Add to dashboard Cite

We present coordinated multiwavelength observations of the high Galactic latitude (b=+50 • ) black hole X-ray binary (BHXB) Swift J1357.2−0933 in quiescence. Our broadband spectrum includes strictly simultaneous radio and X-ray observations, and near-infrared, optical, and ultraviolet data taken 1-2 days later. We detect Swift J1357.2−0933 at all wavebands except for the radio (f 5GHz <3.9 µJy beam −1 ; 3σ rms ). Given current constraints on the distance (2.3-6.3 kpc), its 0.5-10 keV X-ray flux corresponds to an Eddington ratio L X /L Edd = 4 × 10 −9 − 3 × 10 −8 (assuming a black hole mass of 10M ⊙ ). The broadband spectrum is dominated by synchrotron radiation from a relativistic population of outflowing thermal electrons, which we argue to be a common signature of short-period quiescent BHXBs. Furthermore, we identify the frequency where the synchrotron radiation transitions from optically thick-to-thin (ν b ≈ 2 − 5 × 10 14 Hz, which is the most robust determination of a 'jet break' for a quiescent BHXB to date. Our interpretation relies on the presence of steep curvature in the ultraviolet spectrum, a frequency window made observable by the low amount of interstellar absorption along the line of sight. High Galactic latitude systems like Swift J1357.2−0933 with clean ultraviolet sightlines are crucial for understanding black hole accretion at low luminosities.

show abstract

The quiescent spectral energy distribution of V404 Cyg

Cited by 72 publications

References 39 publications

Constraints on relativistic jets in quiescent black hole X-ray binaries from broad-band spectral modelling

Constraints on relativistic jets in quiescent black hole X-ray binaries from broad-band spectral modelling

The radio/X-ray domain of black hole X-ray binaries at the lowest radio luminosities

A clean sightline to quiescence: multiwavelength observations of the high Galactic latitude black hole X-ray binary Swift J1357.2−0933

Contact Info

Product

Resources

About