186 research outputs found
An Isolated Stellar-Mass Black Hole Detected Through Astrometric Microlensing
We report the first unambiguous detection and mass measurement of an isolated stellar-mass black hole (BH). We used the Hubble Space Telescope (HST) to carry out precise astrometry of the source star of the long-duration (t_E ~ 270 days), high-magnification microlensing event MOA-2011-BLG-191/OGLE-2011-BLG-0462, in the direction of the Galactic bulge. HST imaging, conducted at eight epochs over an interval of six years, reveals a clear relativistic astrometric deflection of the background star's apparent position. Ground-based photometry shows a parallactic signature of the effect of the Earth's motion on the microlensing light curve. Combining the HST astrometry with the ground-based light curve and the derived parallax, we obtain a lens mass of 7.1 +/- 1.3 M_Sun and a distance of 1.58 +/- 0.18 kpc. We show that the lens emits no detectable light, which, along with having a mass higher than is possible for a white dwarf or neutron star, confirms its BH nature. Our analysis also provides an absolute proper motion for the BH. The proper motion is offset from the mean motion of Galactic-disk stars at similar distances by an amount corresponding to a transverse space velocity of ~45 km/s, suggesting that the BH received a modest natal 'kick' from its supernova explosion. Previous mass determinations for stellar-mass BHs have come from radial-velocity measurements of Galactic X-ray binaries, and from gravitational radiation emitted by merging BHs in binary systems in external galaxies. Our mass measurement is the first ever for an isolated stellar-mass BH using any technique
Realisation d'un systeme de collection electrostatique de noyaux. Application a la production d'isotopes et aux reactions nucleaires induites par des faiseaux de C a 86 MeV/nucleon
SIGLEAvailable from CEN Saclay, Service de Documentation, 91191 Gif-sur-Yvette Cedex (France) / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
Etude de la radioactivite des isotopes Na, Cl, Cl, Ar et Sc
SIGLEAvailable from CEN Saclay, Service de Documentation, 91191 Gif-sur-Yvette Cedex (France) / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
Etude par spectrometrie X des mecanismes de production de lacunes K, L lors des interactions induites par des particules chargees de quelques MeV/A
SIGLEAvailable from CEN Saclay, Service de Documentation, 91191 Gif-sur-Yvette Cedex (France) / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
Laboratoire d'evaluation des materiels implantables (LEMI)
SIGLEAvailable from INIST (FR), Document Supply Service, under shelf-number : AR 16302 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueMinistere de la Recherche et de la Technologie (MRT), 75 - Paris (France)FRFranc
Les arbitrages entre la communication-produit et la communication institutionnelle au sein des 'strategies environnementales' Le cas des firmes nationales du petrole et de l'energie nucleaire
Available at INIST (FR), Document Supply Service, under shelf-number : DO 2976 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueSIGLEFRFranc
Atomic X-rays associated with the compound nucleus
Published in summary form onlySIGLEAvailable from CEN Saclay, Service de Documentation, 91191 Gif-sur-Yvette Cedex (France) / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
La methode GRAI : une approche efficace de management au service des banques
SIGLEAvailable at INIST (FR), Document Supply Service, under shelf-number : RP 13735 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
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