M. R. Schreiber
A5054096266- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astrophysical Phenomena and Observations
- Gamma-ray bursts and supernovae
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Pulsars and Gravitational Waves Research
- Molecular Spectroscopy and Structure
- High-pressure geophysics and materials
- Granular flow and fluidized beds
- Solar and Space Plasma Dynamics
- Galaxies: Formation, Evolution, Phenomena
- Renal Transplantation Outcomes and Treatments
- Astrophysics and Cosmic Phenomena
- Particle Accelerators and Free-Electron Lasers
- Congenital gastrointestinal and neural anomalies
- Cyclone Separators and Fluid Dynamics
- Soil Mechanics and Vehicle Dynamics
- Phase Equilibria and Thermodynamics
- Fluid Dynamics and Heat Transfer
- Digestive system and related health
- Calibration and Measurement Techniques
- Infective Endocarditis Diagnosis and Management
- Coronary Interventions and Diagnostics
Federico Santa María Technical University
2020-2024
Millenium Nucleus for Planet Formation
2013-2024
Zentralklinik Bad Berka
2010-2023
University of Valparaíso
2012-2021
European Southern Observatory
2010-2020
Centro Científico Tecnológico de Valparaíso
2020
Valparaiso University
2009-2019
Saarland University
2018
Leiber (Germany)
2007-2018
Millennium Science Initiative
2018
The Sloan Extension for Galactic Understanding and Exploration (SEGUE) Survey obtained ≈240,000 moderate-resolution (R ∼ 1800) spectra from 3900 Å to 9000 of fainter Milky Way stars (14.0 < g 20.3) a wide variety spectral types, both main-sequence evolved objects, with the goal studying kinematics populations our Galaxy its halo. are clustered in 212 regions spaced over three quarters sky. Radial velocity accuracies at 18, degrading 20. For signal-to-noise ratio >10 per resolution element,...
Context. The ESO public survey VISTA variables in the Vía Láctea (VVV) started 2010. VVV targets 562 sq. deg Galactic bulge and an adjacent plane region is expected to run for about five years.
We have known for a long time that many of the measured white dwarf (WD) masses in cataclysmic variables (CVs) significantly exceed mean mass single WDs. This was thought to be related observational biases, but recent high-precision measurements WD great number CVs are challenging this interpretation. review CVs, determine WD-mass distribution an extensive sample post-common-envelope binaries (PCEBs) representative progenitors current CV population (pre-CVs) and compare both distributions....
We introduce the Ophiuchus DIsc Survey Employing ALMA (ODISEA), a project aiming to study entire population of Spitzer-selected protoplanetary discs in Molecular Cloud (~300 objects) from both millimeter continuum and CO isotopologues data. Here we present 1.3 mm/230 GHz images 147 targets at 0.2" (28 au) resolution typical rms 0.15 mJy. detect total 133 discs, including individual components 11 binary systems 1 triple system. Fifty-three these are spatially resolved. find clear...
We discuss the properties of 137 cataclysmic variables (CVs) which are included in Sloan Digital Sky Survey (SDSS) spectroscopic data base, and for accurate orbital periods have been measured. 92 these systems new discoveries from SDSS were followed-up more detail over past few years. 45 previously identified as CVs because detection optical outbursts and/or X-ray emission, subsequently re-identified spectroscopy. The period distribution differs dramatically that all known CVs, particular it...
Reconstructing the evolution of post-common-envelope binaries (PCEBs) can constrain current prescriptions common-envelope (CE) evolution. Analyzing a new sample PCEBs we derive constraints on one most important parameters in field close compact binary formation, i.e. CE efficiency alpha. After reconstructing post-CE and based fits to stellar calculations as well parametrized energy equation for that incorporates realistic approximations binding parameter lambda, determine possible...
Planets orbiting post-common envelope binaries provide fundamental information on planet formation and evolution. We searched for such planets in NN Ser ab, an eclipsing short-period binary that shows long-term eclipse time variations. Using published, reanalysed, new mid-eclipse times of ab obtained between 1988 2010, we find excellent agreement with the light-travel-time effect produced by two additional bodies superposed linear ephemeris binary. Our multi-parameter fits accompanied...
Apparent period variations detected in several eclipsing, close-compact binaries are frequently interpreted as being caused by circumbinary giant planets. This interpretation raises the question of origin potential planets that must have either formed primordial disk, together with host binary star, and survived its evolution into a or post-common-envelope disk remained bound to (PCEB). Here we combine current knowledge planet formation statistics around evolved stars theory star aiming...
We present the first volume-limited sample of cataclysmic variables (CVs), selected using accurate parallaxes provided by second data release (DR2) ESA $\mathit{Gaia}$ space mission. The is composed 42 CVs within $150\,$pc, including two new systems discovered data, and $(77 \pm 10)\,$per cent complete. use this to study intrinsic properties Galactic CV population. In particular, density we derive, $\rho=(4.8^{+0.6}_{-0.8}) \times10^{-6}\,\mathrm{pc}^{-3}$, lower than predicted most binary...
We have obtained millimeter-wavelength photometry, high-resolution optical spectroscopy, and adaptive optics near-infrared imaging for a sample of 26 Spitzer-selected transition circumstellar disks. All our targets are located in the Ophiuchus molecular cloud (d ∼ 125 pc) spectral energy distributions (SEDs) suggesting presence inner opacity holes. use these ground-based data to estimate disk mass, multiplicity, accretion rate each object order investigate mechanisms potentially responsible...
Abstract The average white dwarf (WD) masses in cataclysmic variables (CVs) have been measured to significantly exceed those of single WDs, which is the opposite what theoretically expected. We present results binary population synthesis models taking into account consequential angular momentum loss (CAML) that assumed increase with decreasing WD mass. This approach cannot only solve mass problem but also brings agreement theoretical predictions and observations orbital period distribution...
We present 25 new eclipse times of the white dwarf binary NN Ser taken with high-speed camera ULTRACAM on WHT and NTT, RISE Liverpool Telescope, HAWK-I VLT to test two-planet model proposed explain variations in its measured over last years. The planetary survives flying colours, correctly predicting a progressive lag 36 seconds that has set since 2010 compared previous 8 years precise times. Allowing both orbits be eccentric, we find orbital periods 7.9 +/- 0.5 yr 15.3 0.3 yr, masses 2.3...
M dwarfs are prime targets in the hunt for habitable worlds around other stars. This is due to their abundance as well small radii and low masses temperatures, which facilitate detection of temperate, rocky planets orbit them. However, fundamental properties difficult constrain, often limiting our ability characterise they host. Here we test several theoretical relationships by measuring 23 high precision, model-independent binaries with white dwarfs. We find a large scatter these low-mass...
Context. Detached white dwarf + main sequence (WD+MS) systems represent the simplest population of post-common envelope binaries (PCEBs). Since ensemble properties this carries important information about characteristics common-envelope (CE) phase, it deserves close scrutiny. However, most synthesis studies do not fully consider effects observational selection biases samples used to compare with theoretical simulations.
We present high precision, model independent, mass and radius measurements for 16 white dwarfs in detached eclipsing binaries combine these with previously published data to test the theoretical dwarf mass-radius relationship. reach a mean precision of 2.4 per cent 2.7 radius, our best reaching 0.3 0.5 radius. find excellent agreement between measured predicted radii across wide range masses temperatures. also all less than 0.48M$_\odot$ be fully consistent helium core models, but they are...
A low-mass planet around a white dwarf Numerous exoplanets have been detected Sun-like stars. These stars end their lives as dwarfs, which should inherit any surviving planetary systems. Manser et al. found periodic shifts in emission lines from disc of gas orbiting (see the Perspective by Fossati). They used numerical simulations to show that most likely explanation for spectral is within disc. The must be unusually small and dense avoid being ripped apart tidal forces. authors speculate it...
We report on the masses ($M_\mathrm{WD}$), effective temperatures ($T_\mathrm{eff}$) and secular mean accretion rates ($\langle \dot{M} \rangle$) of 43 cataclysmic variable (CV) white dwarfs, 42 which were obtained from combined analysis their $\mathit{Hubble~Space~Telescope}$ ultraviolet data with parallaxes provided by Early Third Data Release $\mathit{Gaia}$ space mission, one dwarf gravitational redshift. Our results double number CV dwarfs an accurate mass measurement, bringing total...