A5082218022- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- Adaptive optics and wavefront sensing
- Scientific Research and Discoveries
- History and Developments in Astronomy
- Geophysics and Gravity Measurements
- Galaxies: Formation, Evolution, Phenomena
- Spectroscopy and Laser Applications
- Distributed and Parallel Computing Systems
- Calibration and Measurement Techniques
- Geomagnetism and Paleomagnetism Studies
- Cosmology and Gravitation Theories
- Astronomical and nuclear sciences
- Space Exploration and Technology
- Solar and Space Plasma Dynamics
- Historical Astronomy and Related Studies
- Atmospheric Ozone and Climate
- Mechanics and Biomechanics Studies
- Spectroscopy and Chemometric Analyses
Tel Aviv University
2016-2025
Max Planck Society
2018
Max Planck Institute for Astronomy
2018
University of California, Santa Barbara
2015
Instituto de Astrofísica de Canarias
2015
EarthTech International (United States)
2010
Harvard University Press
2010
Institute for Advanced Study
2009
Astronomical Institute of the Slovak Academy of Sciences
2007
Argentine National Observatory
2007
We study the statistical characteristics of a box-fitting algorithm to analyze stellar photometric time series in search for periodic transits by extrasolar planets. The searches signals characterized alternation between two discrete levels, with much less spent at lower level. present numerical as well analytical results predict possible detection significance various signal parameters. It is shown that crucial parameter effective signal-to-noise ratio – expected depth transit divided...
We analyzed 3 years of data from the Kepler space mission to derive rotation periods main-sequence stars below 6500 K. Our automated autocorrelation-based method detected between 0.2 and 70 days for 34,030 (25.6%) 133,030 targets (excluding known eclipsing binaries Objects Interest), making this largest sample stellar date. In paper we consider detailed features now well-populated period-temperature distribution demonstrate that period bimodality, first seen by McQuillan, Aigrain & Mazeh...
We suggest a new algorithm to remove systematic effects in large set of lightcurves obtained by photometric survey. The can effects, like the ones associated with atmospheric extinction, detector efficiency, or PSF changes over detector. works without any prior knowledge as long they linearly appear many stars sample. approach, which was originally developed extinction is based on lower rank approximation matrices, an approach already suggested and used chemometrics, for example. proposed...
view Abstract Citations (424) References (14) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Study of Spectroscopic Binaries with TODCOR. I. A New Two-dimensional Correlation Algorithm to Derive the Radial Velocities Two Components Zucker, S. ; Mazeh, T. We propose a generalization cross-correlation technique, obtain simultaneously Doppler shift two components composite spectra. The technique-TODCOR-computes correlation an observed spectrum against...
ABSTRACT The primary Kepler Mission provided nearly continuous monitoring of ∼200,000 objects with unprecedented photometric precision. We present the final catalog eclipsing binary systems within 105 deg 2 field view. This release incorporates full extent data from mission (Q0-Q17 Data Release). As a result, new have been added, additional false positives removed, ephemerides and principal parameters recomputed, classifications revised to rely on analytical models, eclipse timing variations...
view Abstract Citations (502) References (43) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Steps toward Determination of the Size and Structure Broad-Line Region in Active Galactic Nuclei. I. an 8 Month Campaign Monitoring NGC 5548 with IUE Clavel, J. ; Reichert, G. A. Alloin, D. Crenshaw, M. Kriss, Krolik, H. Malkan, Netzer, Peterson, B. Wamsteker, W. Altamore, Baribaud, T. Barr, P. Beck, S. Binette, L. Bromage, E. Brosch, N. Diaz, Filippenko, V. Fricke,...
We report the detection of Kepler-47, a system consisting two planets orbiting around an eclipsing pair stars. The inner and outer have radii 3.0 4.6 times that Earth, respectively. binary star consists Sun-like companion roughly one-third its size, each other every 7.45 days. With orbital period 49.5 days, eighteen transits planet been observed, allowing detailed characterization orbit those planet's is 303.2 although not Earth-like, it resides within classical "habitable zone", where...
We present a large sample of stellar rotation periods for Kepler Objects Interest (KOIs), based on three years public data. These were measured by detecting periodic photometric modulation caused star spots, using an algorithm the autocorrelation function (ACF) light curve, developed recently McQuillan, Aigrain & Mazeh (2013). Of 1919 main-sequence exoplanet hosts analyzed, robust detected 737. Comparing to orbital innermost planet in each system reveals notable lack close-in planets around...
Eighty planetary systems of two or more planets are known to orbit stars other than the Sun. For most, data can be sufficiently explained by non-interacting Keplerian orbits, so dynamical interactions these have not been observed. Here we present 4 sets lightcurves from Kepler spacecraft, which each show multiple transiting same star. Departure timing transits strict periodicity indicates perturbing other: observed variations match forcing frequency planet. This confirms that objects in...
ABSTRACT We infer dynamical masses in eight multiplanet systems using transit times measured from Kepler 's complete data set, including short-cadence where available. Of the 18 that we infer, 10 pass multiple tests for robustness. These are Kepler-26 (KOI-250), Kepler-29 (KOI-738), Kepler-60 (KOI-2086), Kepler-105 (KOI-115), and Kepler-307 (KOI-1576). c has a radius of 1.3 R ⊕ density consistent with an Earth-like composition. Strong timing variation (TTV) signals were detected additional...
Context. The HARPS spectrograph provides state-of-the-art stellar radial velocity (RV) measurements with a precision down to 1 m/s. spectra are extracted dedicated data-reduction software (DRS) and the RVs computed by CCF numerical mask. Aims. aim of this study is three-fold: (i) Create easy access public RV data set. (ii) Apply new SERVAL pipeline spectra, produce more precise (iii) Check whether can be further improved correcting for small nightly systematic effects. Methods. For each star...
The Gaia DR3 Catalogue contains for the first time about eight hundred thousand solutions with either orbital elements or trend parameters astrometric, spectroscopic and eclipsing binaries, combinations of them. This paper aims to illustrate huge potential this large non-single star catalogue. Using together models a catalogue tens thousands stellar masses, lower limits, partly consistent flux ratios, has been built. Properties concerning completeness binary catalogues are discussed,...
ABSTRACT We report discovery of a bright, nearby ($G = 13.8;\, \, d 480\, \rm pc$) Sun-like star orbiting dark object. identified the system as black hole candidate via its astrometric orbital solution from Gaia mission. Radial velocities validated and refined solution, spectroscopy ruled out significant light contributions another star. Joint modelling radial astrometry constrains companion mass $M_2 9.62\pm 0.18\, \mathrm{M}_{\odot }$. The spectroscopic orbit alone sets minimum $M_2\gt 5\,...
We report spectroscopic and photometric follow-up of a dormant black hole (BH) candidate from Gaia DR3. The system, which we call BH2, contains $\sim 1M_{\odot}$ red giant dark companion with mass $M_2 = 8.9\pm 0.3\,M_{\odot}$ that is very likely BH. orbital period, $P_{\rm orb} 1277$ days, much longer than any previously studied BH binary. Our radial velocity (RV) over 7-month period spans more 90% the orbit's dynamic range in RV excellent agreement predictions solution. UV imaging...
Context. Gaia has been in operations since 2014. The third data release expands from the early (EDR3) 2020 by providing 34 months of multi-epoch observations that allowed us to probe, characterise and classify systematically celestial variable phenomena. Aims. We present a summary variability processing analysis photometric spectroscopic time series 1.8 billion sources done for DR3. Methods. used statistical Machine Learning methods sources. Training sets were built global revision major...
Gaia DR3 contains 1.8 billion sources with G-band photometry, 1.5 of which BP and RP complemented by positions on the sky, parallax, proper motion. The median number field-of-view transits in three photometric bands is between 40 44 measurements per source covers 34 months data collection. We pursue a classification Galactic extra-galactic objects that are detected as variable across whole sky. Supervised machine learning (eXtreme Gradient Boosting Random Forest) was employed to generate...
Abstract The Ultraviolet Transient Astronomy Satellite (ULTRASAT) is scheduled to be launched geostationary orbit in 2027. It will carry a telescope with an unprecedentedly large field of view (204 deg 2 ) and near-ultraviolet (NUV; 230–290 nm) sensitivity (22.5 mag, 5 σ , at 900 s). ULTRASAT conduct the first wide-field survey transient variable NUV sources revolutionize our ability study hot Universe. explore new parameter space energy timescale (months-long light curves minutes cadence),...
Gravitational waves from black-hole merging events have revealed a population of extra-galactic BHs residing in short-period binaries with masses that are higher than expected based on most stellar evolution models - and also known stellar-origin black holes our Galaxy. It has been proposed those high-mass the remnants massive metal-poor stars. Gaia astrometry is to uncover many Galactic wide-binary systems containing dormant BHs, which may not detected before. The study this will provide...
ABSTRACT The third data release of Gaia was the first to include orbital solutions assuming non-single stars. Here, we apply astrometric triage technique Shahaf et al. identify binary star systems with companions that are not single main-sequence Gaia’s synthetic photometry these binaries is used distinguish between likely have white-dwarf and those may be hierarchical triples. study uncovered a population nearly $3\, 200$ binaries, characterized by separations on order an astronomical unit,...
We report 25,563 radial velocity measurements for 1359 single-lined stars in the Carney-Latham sample of 1464 selected high proper motion. For 171 these, we present spectroscopic orbital solutions. find no obvious difference between binary characteristics halo and disk populations. The observed frequency is same, period distributions are consistent with hypothesis that two sets binaries were drawn from same parent population. This suggests metallicity general, radiative opacities particular,...
We report a spectroscopic orbit with period P=3.52433+/-0.00027 days for the planetary companion that transits solar-type star HD 209458. For metallicity, mass, and radius of star, we derive [Fe/H&sqbr0;=0.00+/-0.02, M*=1.1+/-0.1 M middle dot in circle, R*=1.2+/-0.1 R circle. This is based on new analysis iron lines our HIRES template spectrum also absolute magnitude, effective temperature, color it uses isochrones from four different sets stellar evolution models. Using these values...
We report rotation periods for 254 stars in an area 40' × 80' centered on the Orion Nebula. show that these are likely members of young (∼106 yr) OBIc/d association. The period distribution we determine, which is sensitive to 0.1 < P 8 days, shows a sharp cutoff 0.5 corresponding breakup velocity stars. Above days consistent with uniform distribution; do not find evidence "gap" at 4–5 days. signatures active accretion among all periods; does occur preferentially slow rotators our sample. no...