Start year
1997
Organizational Unit
Organizing institutions
Grants related:
General
Description
Accreting black-holes and neutron stars in X-ray binaries provide an ideal laboratory for exploring the physics of compact objects, yielding not only confirmation of the existence of stellar mass black holes via dynamical mass measurements, but also the best opportunity for probing high-gravity environments and the physics of accretion; the most efficient form of energy production known. The latter is an essential physical process to understand the universe, playing a crucial role in galactic and extra-galactic astronomy.
This project has the following scientific goals:
- X-ray binaries offer the opportunity to study accretion as its best, since their relevant changes occur on convenient time-scales for human beings. This project focuses on the universal relation between black-hole accretion and ejection processes in the form of collimated jets and wide-angle winds. We will focus on the general properties and astrophysical impact of the cold optical accretion disc wind that our group has discovered. We want to understand how frequent these winds are, which is their impact in the black-hole accretion process, and what is their relation with jets and hot X-ray winds. Likewise, we carry out very detailed X-ray spectral studies on the different accretion states and geometries and their evolution with luminosity.
- We want to define the mass distribution of black-holes and neutron stars. Thus, we continue our contribution to one of the fundamental experiments in modern astrophysics by measuring dynamical masses in X-ray binaries. We expect to significantly improve the observed mass distribution of compact objects. This will allow testing models of supernovae explosions and close binary evolution as well as setting constraints on the equation of state of nuclear matter. We will measure masses in newly discovered or known transient X-ray binaries. In addition, we will also search for the large number of dormant X-ray binaries expected in the Galaxy and suitable for dynamical studies.
- To study the structure of accretion discs in different energy bands (optical-X rays). The high energy spectral distribution and time variability during outburst is important to constrain the eruption models and accretion disc properties (e.g. radius of advective disc) as well as to constrain the contribution of the jet to the optical and infrared emission of the system.
see group web page: https://research.iac.es/proyecto/compactos/pages/en/introduction.php
Members
Principal investigator
Montserrat
Armas Padilla
Project staff
Jorge
Casares Velázquez
Tariq
Shahbaz
Teodoro
Muñoz Darias
Manuel Ángel
Pérez Torres
Virginia Anahi
Cúneo
María Guayente
Panizo Espinar
Ignacio
González Martínez-Pais
Pablo
Rodríguez Gil
Jonay Isai
González Hernández
Collaborators
Prof.
P. Charles
Prof.
R. Fender
Prof.
P. Jonker -
Prof.
T. Marsh
Dr.
D. Steeghs
Dr.
S. Motta
Prof.
T. Belloni
Dr.
K. O'Brien
Dr.
B. Gaensicke
Prof.
J.M. Paredes
Dr.
M. Ribó
Dr.
J. Marti
Prof.
S. Campana
Dr.
P. D’Avanzo
Dr.
I. Negueruela
Dr.
J.M. Corral-Santana
Dr.
D. Russell
Prof.
Rudy Wijnands
Dr.
N. Degenaar
Dr.
A. de Ugarte
Dr.
Y. Ueda
Dr.
R.I. Hynes
María Jesús
Arevalo Morales
Josefa
Becerra González
Artemio
Herrero Davo
Garik
Israelian
Results
- Our team has led the multi-wavelength study of the two 2015 outbursts of the Black-hole transient V404 Cyg. In 2018, we published a global paper which include all the spectroscopy taken during the 1989 and 2015 campaigns.
- We have presented solid evidence for the presence of very similar wind to that found in V404 Cyg in another black hole transient, V4641 Sgr.
- We published the final paper as well as a pilot study on a novel method developed by the group. It aims at discovering and measuring masses of black hole transient in quiescence. This method has the potential of increasing the known population of these systems by a factor of three.
- We measured the mass of the neutron star in PSR J2215+5135 and found it is one of the heaviest known to date.
- We presented the first detailed study on the ultra-compact system SLX 1737-282.
Scientific activity
Related publications
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The spotty donor star in the X-ray transient Cen X-4We accurately determine the fundamental system parameters of the neutron star X-ray transient Cen X-4 solely using phase-resolved high-resolution UV-Visual Echelle Spectrograph spectroscopy. We first determine the radial-velocity curve of the secondary star and then model the shape of the phase-resolved absorption line profiles using an X-rayShahbaz, T. et al.
Advertised on:
32014 -
The accretion-ejection coupling in the black hole candidate X-ray binary MAXI J1836-194We present the results of our quasi-simultaneous radio, submm, infrared, optical and X-ray study of the Galactic black hole candidate X-ray binary MAXI J1836-194 during its 2011 outburst. We consider the full multiwavelength spectral evolution of the outburst, investigating whether the evolution of the jet spectral break (the transition betweenRussell, T. D. et al.
Advertised on:
22014 -
Unveiling recurrent jets of the ULX Holmberg II X-1: evidence for a massive stellar-mass black hole?We report on the discovery of an apparent triple radio structure hidden inside the radio bubble of the ultraluminous X-ray source Holmberg II X-1. The morphology is consistent with a collimated jet structure, which is observed to emit optically thin synchrotron radiation. The central component has a steep radio spectrum and is brighter than theCseh, D. et al.
Advertised on:
32014 -
The multiwavelength polarization of Cygnus X-1Polarization measurements of the microquasar Cygnus X-1 exist at γ-ray, X-ray, ultraviolet, optical and radio frequencies. The γ-ray emission has been shown to be highly linearly polarized. Here, we present new infrared polarimetric data of Cygnus X-1 taken with the 10.4 m Gran Telescopio Canarias and the 4.2 m William Herschel Telescope. We showShahbaz, T. et al.
Advertised on:
32014 -
A Be-type star with a black-hole companionStellar-mass black holes have all been discovered through X-ray emission, which arises from the accretion of gas from their binary companions (this gas is either stripped from low-mass stars or supplied as winds from massive ones). Binary evolution models also predict the existence of black holes accreting from the equatorial envelope of rapidlySimón-Díaz, S. et al.
Advertised on:
12014 -
Ultraviolet-excess sources with a red/infrared counterpart: low-mass companions, debris discs and QSO selectionWe present the result of the cross-matching between ultraviolet (UV)-excess sources selected from the UV-Excess Survey of the Northern Galactic Plane (UVEX) and several infrared (IR) surveys (2MASS, UKIDSS and WISE). From the position in the (J - H) versus (H - K) colour-colour diagram, we select UV-excess candidate white dwarfs with an M-dwarfZijlstra, Albert et al.
Advertised on:
22014 -
The neutron star transient and millisecond pulsar in M28: from sub-luminous accretion to rotation-powered quiescenceThe X-ray transient IGR J18245-2452 in the globular cluster M28 contains the first neutron star (NS) seen to switch between rotation-powered and accretion-powered pulsations. We analyse its 2013 March-April 25 d long outburst as observed by Swift, which had a peak bolometric luminosity of ˜6 per cent of the Eddington limit (LEdd), and give detailedPooley, David et al.
Advertised on:
22014 -
Fast orbital decays of black hole X-ray binaries: XTE J1118+480 and A0620-00★We present new 10.4 m-GTC/OSIRIS spectroscopic observations of the black hole X-ray binary XTE J1118+480 that confirm the orbital period decay at dot{P}=-1.90± 0.57 ms yr-1. This corresponds to a period change of -0.88 ± 0.27 μs per orbital cycle. We have also collected observations of the black hole X-ray binary A0620-00 to derive an orbitalCasares, J. et al.
Advertised on:
22014 -
The evolving polarized jet of black hole candidate Swift J1745-26Swift J1745-26 is an X-ray binary towards the Galactic Centre that was detected when it went into outburst in 2012 September. This source is thought to be one of a growing number of sources that display `failed outbursts', in which the self-absorbed radio jets of the transient source are never fully quenched and the thermal emission from theCurran, P. A. et al.
Advertised on:
22014 -
Discovery of the Third Transient X-Ray Binary in the Galactic Globular Cluster Terzan 5We report and study the outburst of a new transient X-ray binary (XRB) in Terzan 5, the third detected in this globular cluster, Swift J174805.3-244637 or Terzan 5 X-3. We find clear spectral hardening in Swift/XRT data during the outburst rise to the hard state, thanks to our early coverage (starting at LX ~ 4 × 1034 erg s–1) of the outburst. ThisWijnands, Rudy et al.
Advertised on:
12014 -
Broad-band monitoring tracing the evolution of the jet and disc in the black hole candidate X-ray binary MAXI J1659-152MAXI J1659-152 was discovered on 2010 September 25 as a new X-ray transient, initially identified as a gamma-ray burst, but was later shown to be a new X-ray binary with a black hole as the most likely compact object. Dips in the X-ray light curves have revealed that MAXI J1659-152 is the shortest period black hole candidate identified to datevan der Horst, A. J. et al.
Advertised on:
122013 -
The origin of the tilted disc in the low-mass X-ray binary GR Mus (XB 1254-690)We present photometric and spectroscopic observations of the low-mass X-ray binary GR Mus (XB 1254-690), and find strong evidence for the presence of a negative superhump with a period that is 2.4 ± 0.3 per cent shorter than the orbital. This provides further support that GR Mus indeed harbours a precessing accretion disc (with a period of 6.74 ± 0Cornelisse, R. et al.
Advertised on:
112013 -
Towards a dynamical mass of the ultraluminous X-ray source NGC 5408 X-1We obtained multi-epoch Very Large Telescope optical spectroscopic data in 2011 and 2012 on the ultraluminous X-ray source NGC 5408 X-1. We confirm that the He II λ4686 line has a broad component with an average full width at half-maximum of v = 780 ± 64 km s-1 with a variation of ˜13 per cent during observations spanning over four years, and isGrisé, F. et al.
Advertised on:
112013 -
A determination of the space density and birth rate of hydrogen-line (DA) white dwarfs in the Galactic plane, based on the UVEX surveyWe present a determination of the average space density and birth rate of hydrogen-line (DA) white dwarfs within a radius of 1 kpc around the Sun, based on an observational sample of 360 candidate white dwarfs with g 19.5 and (g - r) 0.4, selected from the UV-Excess (UVEX) survey of the northern Galactic plane, in combination with a theoreticalVerbeek, K. et al.
Advertised on:
102013 -
The X-Ray Properties of the Black Hole Transient MAXI J1659-152 in QuiescenceWe present new Chandra X-ray observations of the transient black hole X-ray binary MAXI J1659-152 in quiescence. These observations were made more than one year after the end of the source's 2010-2011 outburst. We detect the source at a 0.5-10 keV flux of 2.8(8) × 10–15 erg s–1 cm–2, which corresponds to a luminosity of ~1.2 × 1031 (d/6 kpc)2 erg sHoman, J. et al.
Advertised on:
92013 -
Evidence for quiescent synchrotron emission in the black hole X-ray transient Swift J1357.2-0933We 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 J1357.2Shahbaz, T. et al.
Advertised on:
92013 -
A return to strong radio flaring by Circinus X-1 observed with the Karoo Array Telescope test array KAT-7Circinus X-1 is a bright and highly variable X-ray binary which displays strong and rapid evolution in all wavebands. Radio flaring, associated with the production of a relativistic jet, occurs periodically on a ˜17-d time-scale. A longer term envelope modulates the peak radio fluxes in flares, ranging from peaks in excess of a Jansky in the 1970sArmstrong, R. P. et al.
Advertised on:
82013 -
Discovery of twin kHz quasi-periodic oscillations in the low-mass X-ray binary XTE J1701-407We report the discovery of kHz quasi-periodic oscillations (QPOs) in three Rossi X-ray Timing Explorer observations of the low-mass X-ray binary XTE J1701-407. In one of the observations we detect a kHz QPO with a characteristic frequency of 1153 ± 5 Hz, while in the other two observations we detect twin QPOs at characteristic frequencies of 740 ±Strohmayer, Tod et al.
Advertised on:
82013 -
A long-term X-ray monitoring of the ultraluminous X-ray source NGC 5408 X-1 with Swift reveals the presence of dips but no orbital periodNGC 5408 X-1 is a well-studied ultraluminous X-ray source (ULX) that has been seen to emit in X-rays persistently above the Eddington limit of a stellar mass black hole for years. In this paper we report on the most extensive X-ray monitoring of a ULX, using more than 4 yr of observations from the Swift satellite. We find that the 115 d periodicityGrisé, F. et al.
Advertised on:
82013 -
A 420-day X-ray/optical modulation and extended X-ray dips in the short-period transient Swift J1753.5-0127We have discovered a ˜420-d modulation, with associated X-ray dips, in Rossi X-Ray Timing Explorer-All Sky Monitor/Monitor of All-Sky X-ray Image/Swift-Burst Alert Telescope archival light curves of the short-period (3.2 h) black hole X-ray transient, Swift J1753.5-0127. This modulation only appeared at the end of a gradual re-brighteningCasares, J. et al.
Advertised on:
72013
