Search results for "Astrophysical"

showing 10 items of 4966 documents

Spectra of high-mass X-ray binaries

2016

High-mass X-ray binaries are bright X-ray sources. The high-energy emission is caused by the accretion of matter from the massive companion onto a neutron star. The accreting material comes from either the strong stellar wind in binaries with supergiant companions or the circumstellar disk in Be/X-ray binaries. In either case, the H{alpha} line stands out as the main source of information about the state of the accreting material. We present the results of our monitoring program to study the long-term variability of the H{alpha} line in high-mass X-ray binaries. Our aim is to characterise the optical variability timescales and study the interaction between the neutron star and the accreting…

observational astronomyAstrophysics and AstronomyStellar AstronomyX-ray binary starsAstrophysics::High Energy Astrophysical PhenomenaPhysicsAstrophysics::Solar and Stellar AstrophysicsAstrophysics::Earth and Planetary AstrophysicsX ray binary starsNatural SciencesAstrophysics::Galaxy AstrophysicsSpectroscopy
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INTEGRAL observations of GRB 070311

2008

We present prompt {gamma}-ray, early NIR/optical, late optical and X-ray observations of the peculiar GRB 070311 discovered by INTEGRAL, in order to gain clues on the mechanisms responsible for the prompt {gamma}-ray pulse as well as for the early and late multi-band afterglow of GRB 070311. We fitted with empirical functions the gamma-ray and optical light curves and scaled the result to the late time X-rays.

observational astronomyAstrophysics and AstronomyX ray sourcesGamma-ray astronomyAstrophysics::High Energy Astrophysical PhenomenaPhysicsGamma ray astronomyNatural SciencesX-ray sourcescosmology
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XMM observations of IC 2391 stars

2006

We present X-ray spectral and timing analysis of members of the young open cluster IC 2391 observed with the XMM-Newton observatory. We detected 99 X-ray sources by analysing the summed data obtained from MOS1, MOS2 and pn detectors of the EPIC camera; 24 of them are members, or probable members, of the cluster. Stars of all spectral types have been detected, from the early-types to the late-M dwarfs. Cone search capability for table J/A+A/430/287/table1 (XMM-Newton sources in the IC 2391 region, as detected in the combined EPIC image.) Cone search capability for table J/A+A/430/287/table2 (X-ray and optical properties of IC 2391 members, and upper limits in the combined EPIC image.)

observational astronomyOpen star clustersPhotometryAstrophysics and AstronomyX ray sourcesStellar AstronomyAstrophysics::High Energy Astrophysical PhenomenaPhysicsAstrophysics::Solar and Stellar AstrophysicsNatural SciencesX-ray sourcescosmology
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TANAMI monitoring of Centaurus A.

2015

Centaurus A (Cen A) is the closest radio-loud active galactic nucleus. Very Long Baseline Interferometry (VLBI) enables us to study the spectral and kinematic behavior of the radio jet-counterjet system on milliarcsecond scales, providing essential information for jet emission and propagation models. In the framework of the TANAMI monitoring, we investigate the kinematics and complex structure of Cen A on subparsec scales. We have been studying the evolution of the central parsec jet structure of Cen A for over 3.5-years. The proper motion analysis of individual jet components allows us to constrain jet formation and propagation and to test the proposed correlation of increased high-energy …

observational astronomygalactic and extragalactic astronomyAstrophysics and AstronomyActive galactic nucleihigh energy astrophysicsAstrophysics::High Energy Astrophysical PhenomenaPhysicsRadio galaxiesAstrophysics::Cosmology and Extragalactic AstrophysicsNatural SciencesGalaxiesAstrophysics::Galaxy AstrophysicsVery long baseline interferometry
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The gNLS1 galaxy PKS 2004-447. VLBI images

2016

Gamma-ray-detected radio-loud narrow-line Seyfert 1 (g-NLS1) galaxies constitute a small but interesting sample of the g-ray-loud AGN. The radio-loudest g-NLS1 known, PKS 2004-447, is located in the southern hemisphere and is monitored in the radio regime by the multiwavelength monitoring programme TANAMI. We aim for the first detailed study of the radio morphology and long-term radio spectral evolution of PKS 2004-447, which are essential for understanding the diversity of the radio properties of g-NLS1s. The TANAMI VLBI monitoring program uses the Australian Long Baseline Array (LBA) and telescopes in Antarctica, Chile, New Zealand, and South Africa to monitor the jets of radio-loud activ…

observational astronomygalactic and extragalactic astronomyAstrophysics and AstronomyActive galactic nucleihigh energy astrophysicsAstrophysics::High Energy Astrophysical PhenomenaPhysicsRadio galaxiesAstrophysics::Cosmology and Extragalactic AstrophysicsNatural SciencesGalaxiesAstrophysics::Galaxy AstrophysicsVery long baseline interferometry
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3C 279 Event Horizon Telescope imaging

2020

3C 279 is an archetypal blazar with a prominent radio jet that show broadband flux density variability across the entire electromagnetic spectrum. We use an ultra-high angular resolution technique - global Very Long Baseline Interferometry (VLBI) at 1.3mm (230GHz) - to resolve the innermost jet of 3C 279 in order to study its fine-scale morphology close to the jet base where highly variable gamma-ray emission is thought to originate, according to various models. The source was observed during four days in April 2017 with the Event Horizon Telescope (EHT) at 230 GHz, including the phased Atacama Large Millimeter/submillimeter Array (ALMA), at an angular resolution of ~20uarcsec (at a redshif…

observational astronomygalactic and extragalactic astronomyAstrophysics and AstronomyInterferometryAstrophysics::High Energy Astrophysical PhenomenaRadio galaxiesPhysicsGalaxiesNatural Sciences
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"Table 2" of "Investigations of anisotropic flow using multi-particle azimuthal correlations in pp, p-Pb, Xe-Xe, and Pb-Pb collisions at the LHC"

2019

$v_3\{2\}$ with $|\Delta \eta| > 1.0$ in pp collisions at $\sqrt{s} = 13$ TeV.

p p --> CHARGED X13000.0Astrophysics::High Energy Astrophysical PhenomenaHigh Energy Physics::Experimentv32Gap10Nuclear Experiment
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"Table 7" of "Investigations of anisotropic flow using multi-particle azimuthal correlations in pp, p-Pb, Xe-Xe, and Pb-Pb collisions at the LHC"

2019

SC$(3,2)$ with 3-subevent method in pp collisions at $\sqrt{s} = 13$ TeV.

p p --> CHARGED X13000.0Astrophysics::High Energy Astrophysical PhenomenaHigh Energy Physics::PhenomenologyHigh Energy Physics::ExperimentNuclear Experimentsc32_3sub
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"Table 4" of "Investigations of anisotropic flow using multi-particle azimuthal correlations in pp, p-Pb, Xe-Xe, and Pb-Pb collisions at the LHC"

2019

$v_2\{4\}$ with 3-subevent method in pp collisions at $\sqrt{s} = 13$ TeV.

p p --> CHARGED X13000.0Astrophysics::High Energy Astrophysical PhenomenaHigh Energy Physics::PhenomenologyHigh Energy Physics::ExperimentNuclear Experimentv24_3sub
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"Table 6" of "Investigations of anisotropic flow using multi-particle azimuthal correlations in pp, p-Pb, Xe-Xe, and Pb-Pb collisions at the LHC"

2019

SC$(4,2)$ with 3-subevent method in pp collisions at $\sqrt{s} = 13$ TeV.

p p --> CHARGED X13000.0Astrophysics::High Energy Astrophysical PhenomenaHigh Energy Physics::PhenomenologyHigh Energy Physics::Experimentsc42_3subNuclear Experiment
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