Start year
1988
Organizational Unit
Organizing institutions
Grants related:
General
Description
The study of binary stars is essential to stellar astrophysics. A large number of stars form and evolve within binary systems. Therefore, their study is fundamental to understand stellar and galactic evolution. Particularly relevant is that binary systems are still the best source of precise stellar mass and radius measurements.
Research lines:
- Determination of absolute parameters of Algol-type eclipsing binaries. In 2006 we started a new project to derive accurate masses and radii of low-mass eclipsing binaries of spectral type M. These will be confronted with theoretical predictions for the lower main sequence.
- Study of the structure and evolution of cataclysmic variables (CVs). Among the main goals we highlight a fundamental test of the current evolution theory, which will observationally prove or discard several of its predictions. In doing so, population studies on both the observed minimum orbital period region (~ 80 min) and the upper boundary of the period gap (in the 3-4.5 hour orbital period range) are being performed. On the other hand, our research has demonstrated the existence of a huge pile-up of intrinsically very luminous CVs (with the highest mass transfer rates known), with orbital periods just above 3 hours, in apparent contradiction to theoretical expectations. The masses of these systems are being determined using ToO time in 8-m class telescopes as VLT and Gemini, and the 10.4-m GTC when a system falls into a low brightness state characterised by the quenching of the mass transfer from the donor star to the white dwarf.
- Study of central binary stars of planetary nebulae. One plausible effect leading to bipolar shapes in planetary nebulae is the presence of a progenitor binary star in their centres, containing at least one white dwarf. This project is aimed at finding a significant "bipolarity-binarity" correlation within bipolar planetary nebulae. Further, the history of the mass ejection episodes will give clues to the common-envelope stage, still poorly understood.
- In mid-2017 we started another research line in the field of white dwarfs: the study of post-planetary remnants around these stars, which can greatly benefit from our studies of accretion discs in cataclysmic variables.
Members
Principal investigator
Pablo
Rodríguez Gil
Project staff
Manuel Ángel
Pérez Torres
Tariq
Shahbaz
Dr.
Vikram Dhillon
Ignacio
González Martínez-Pais
Montserrat
Armas Padilla
Teodoro
Muñoz Darias
Jorge
Casares Velázquez
María Jesús
Arevalo Morales
Carlos
Lázaro Hernando
Collaborators
Dr.
B. T. Gänsicke
Dr.
T. R. Marsh
Dr.
R. Iglesias Marzoa
Dr.
M. López Morales
Dr.
P. Abraham
Dr.
D. Steeghs
Dr.
E. Breedt
Dr.
L. Schmidtobreick
Dr.
J. M. Corral Santana
Dr.
S. B. Potter
Dr.
W. Skidmore
Dr.
P. Hakala
Prof.
P. G. Jonker
Dr.
K. S. Long
Dr.
G. Sala
Dr.
Nancy Elías de la Rosa
Dr.
M. Hernanz
Results
- Many white dwarf stars show signs of having accreted smaller bodies, implying that they may host planetary systems. A small number of these systems contain gaseous debris discs, visible through emission lines. We found a stable 123.4-minute periodic variation in the strength and shape of the Ca II emission line profiles originating from the debris disc around the white dwarf SDSS J122859.93+104032.9. We interpret this short-period signal as the signature of a solid-body planetesimal held together by its internal strength. Results published in Science.
- Discovery of a giant bubble-like shell around M31N 2008–12a, the recurrent nova with the shortest eruption recurrence period (one year). Results published in Nature.
- A fast GTC/OSIRIS spectrophotometric study of the white dwarf WD 1145+017 has been published in Monthly Notices of the Royal Astronomical Society that reports confirmation of the evolution of the periodic transits that occur every 4.5 hours. The deepest transit detected to date has been modelled with six equally spaced fragments of the disrupting planetesimal.
- In 2018 an International Time Programme for follow-up of gravitational wave events was awarded (PI Jonker, SRON, The Netherlands). Several members of the projects are co-Is. Rodríguez-Gil will serve as chair on the Executive Committee.
Scientific activity
Related publications
-
Orbital periods of cataclysmic variables identified by the SDSS - III. Time-series photometry obtained during the 2004/5 International Time Project on La PalmaWe present time-resolved CCD photometry of 15 cataclysmic variables (CVs) identified by the Sloan Digital Sky Survey (SDSS). The data were obtained as part of the 2004/2005 International Time Programme on La Palma. We discuss the morphology of the light curves and the CV subtypes, and give accurate orbital periods for 11 systems. Nine systems areDillon, M. et al.
Advertised on:
52008 -
ETHOS 1: a high-latitude planetary nebula with jets forged by a post-common-envelope binary central starWe report on the discovery of ETHOS 1 (PN G068.1+11.0), the first spectroscopically confirmed planetary nebula (PN) from a survey of the SuperCOSMOS Science Archive for high-latitude PNe. ETHOS 1 stands out as one of the few PNe to have both polar outflows (jets) travelling at 120 ± 10 km s-1 and a close binary central star. The light curveMiszalski, B. et al.
Advertised on:
52011 -
Discovery of Hα satellite emission in a low state of the SW Sextantis star BB DoradusBB Dor was observed during its low state in 2009. Signatures of both binary components are revealed in the average optical spectrum; no signature of accretion is observed. Narrow emission lines of Hα, He I and Na D, as well as TiO absorption troughs, trace the motion of the irradiated secondary star. We detect two additional components in the HαSchmidtobreick, L. et al.
Advertised on:
52012 -
Discovery of close binary central stars in the planetary nebulae NGC 6326 and NGC 6778We present observations proving the close binary nature of the central stars belonging to the planetary nebulae (PNe) NGC 6326 and NGC 6778. Photometric monitoring reveals irradiated lightcurves with orbital periods of 0.372 and 0.1534 days, respectively, constituting firm evidence that they passed through a common-envelope (CE) phase. Unlike mostMiszalski, B. et al.
Advertised on:
72011 -
An evolved donor star in the long-period cataclysmic variable HS 0218+3229Context: We present time-resolved spectroscopy and photometry of HS 0218+3229, a new long-period cataclysmic variable discovered within the Hamburg Quasar Survey. It is one of the few systems that allow a dynamical measurement of the masses of the stellar components. Aims: We combine the analysis of time-resolved optical spectroscopy and R-bandRodríguez-Gil, P. et al.
Advertised on:
32009 -
A Planetary Nebula around Nova V458 Vulpeculae Undergoing Flash IonizationNova V458 Vul erupted on 2007 August 8 and reached a visual magnitude of 8.1 a few days later. Hα images obtained 6 weeks before the outburst as part of the IPHAS Galactic plane survey reveal an 18th magnitude progenitor surrounded by an extended nebula. Subsequent images and spectroscopy of the nebula reveal an inner nebular knot increasingWesson, R. et al.
Advertised on:
112008 -
Absolute parameters of the Algol binary Z VulSpectra in the wavelength range 4230-9150 Å and the first light curves of Z Vul in the infrared J, H and K bands are presented. Our infrared JHK light curves and radial velocities, together with published radial velocity and UBV data are analyzed in order to determine a new set of stellar parameters. This allows us to determine new absoluteLazaro, C. et al.
Advertised on:
82009 -
A photometric and spectroscopic study of the binary V1430 AqlWe present the first infrared light curves of the binary V1430 Aql, in the bands J and K, plus V, R and I light curves and spectra covering the ranges of Hβ, Hα and Ca II-IRT lines. Our VRIJK data, together with published radial velocity curves, are analyzed to determine the orbital and stellar parameters of the system. Both stellar componentsLázaro, C. et al.
Advertised on:
72012 -
Optical photometry and Halpha Spectroscopy of SWIFT J1910.2-0546/MAXI J1910-057We report on optical photometry and spectroscopy of the black hole X-ray transient Swift J1910.2-0546/MAXI J1910-057 (Krimm at al. ATel #4139, Usui et al. ATel #4140). R-band photometry (time resolution 27s) over an interval of 3.1 hr was obtained using ALFOSC on the 2.5m Nordic Optical Telescope (NOT) on the night of 21 July 2012. The light curveCasares, J. et al.
Advertised on:
82012 -
Near-IR brightening of the blazar CTA 102 (2230+114) observed by the GASPThe GLAST-AGILE Support Program (GASP) of the Whole Earth Blazar Telescope (WEBT) reports on the recent observation of a strong near-IR brightening of the gamma-loud quasar CTA 102. This is one of the 28 blazars for which the GASP performs a long-term, multiwavelength monitoring. Observations performed at the Teide Observatory on 2012 June 5.2 UTCarnerero, M. I. et al.
Advertised on:
62012 -
SDSS J123813.73 - 033933.0: A Cataclysmic Variable Evolved Beyond the Period MinimumWe present infrared JHK photometry of the cataclysmic variable (CV) SDSS J123813.73 - 033933.0 and analyze it along with optical spectroscopy, demonstrating that the binary system is most probably comprised of a massive white dwarf with T eff = 12000 ± 1000 K and a brown dwarf of spectral type L4. The inferred system parameters suggest that thisAviles, A. et al.
Advertised on:
32010 -
The magnetic SW Sextantis star RXJ1643.7+3402We present time-resolved spectroscopy and circular spectropolarimetry of the SW Sex star RXJ1643.7+3402. We find significant polarization levels exhibiting a variability at a period of 19.38 +/- 0.39 min. In addition, emission-line flaring is found predominantly at twice the polarimetric period. These two findings are strong evidences in favour ofRodríguez-Gil, P. et al.
Advertised on:
52009 -
Absolute parameters of the short-period binary HY Virginis from JHK light curves and spectroscopyWe present the first light curves in the infrared J, H and K filters of HY Vir. Based on HY Vir and template stars spectra in the region 8440 8870 Å, we classify as F0 both stellar components of the binary. Also, we obtain the first radial velocity curves of the system. The analysis of the JHK light curves is carried out using a code based in ATLASMartínez-País, I. G. et al.
Advertised on:
72008 -
IPHAS and the symbiotic stars . II. New discoveries and a sample of the most common mimicsContext. Knowledge of the total population of symbiotic stars in the Galaxy is important for understanding basic aspects of stellar evolution in interacting binaries and the relevance of this class of objects in the formation of supernovae of type Ia. Aims: In a previous paper, we presented the selection criteria needed to search for symbioticCorradi, R. L. M. et al.
Advertised on:
12010 -
Initial data release from the INT Photometric Hα Survey of the Northern Galactic Plane (IPHAS)The INT/WFC Photometric Hα Survey of the Northern Galactic Plane (IPHAS) is an imaging survey being carried out in Hα, r' and i' filters, with the Wide Field Camera (WFC) on the 2.5-m Isaac Newton Telescope (INT) to a depth of r' = 20 (10σ). The survey is aimed at revealing the large scale organization of the Milky Way and can be applied toGonzález-Solares, E. A. et al.
Advertised on:
72008 -
The pulsation modes of the pre-white dwarf PG 1159-035Context: PG 1159-035, a pre-white dwarf with Teff≃ 140 000 K, is the prototype of both two classes: the PG 1159 spectroscopic class and the DOV pulsating class. Previous studies of PG 1159-035 photometric data obtained with the Whole Earth Telescope (WET) showed a rich frequency spectrum allowing the identification of 122 pulsation modes. AnalyzingCosta, J. E. S. et al.
Advertised on:
12008 -
Transit timing analysis of CoRoT-1bContext. CoRoT, the pioneer space-based transit search, steadily provides thousands of high-precision light curves with continuous time sampling over periods of up to 5 months. The transits of a planet perturbed by an additional object are not strictly periodic. By studying the transit timing variations (TTVs), additional objects can be detected inCsizmadia, Sz. et al.
Advertised on:
22010 -
The UV-Excess survey of the northern Galactic planeThe UV-Excess survey of the northern Galactic plane images a 10° × 185° wide band, centred on the Galactic equator using the 2.5-m Isaac Newton Telescope in four bands (I5875) down to ~21-22 mag ( in I5875). The setup and data reduction procedures are described. Simulations of the colours of main-sequence stars, giant, supergiants, DA and DB whiteGroot, Paul J. et al.
Advertised on:
102009 -
The Necklace: equatorial and polar outflows from the binary central star of the new planetary nebula IPHASX J194359.5+170901IPHASX J194359.5+170901 is a new high-excitation planetary nebula with remarkable characteristics. It consists of a knotty ring expanding at a speed of 28 km s-1, and a fast collimated outflow in the form of faint lobes and caps along the direction perpendicular to the ring. The expansion speed of the polar caps is ˜100 km s-1, and theirCorradi, R. L. M. et al.
Advertised on:
12011 -
Searching for flickering statistics in T CrBWe analyse V-band photometry of the aperiodic variability in T CrB. By applying a simple idea of angular momentum transport in the accretion disc, we have developed a method to simulate the statistical distribution of flare durations with the assumption that the aperiodic variability is produced by turbulent elements in the disc. Both cumulativeDobrotka, A. et al.
Advertised on:
32010
