R - Institut d`Astrophysique de Paris
... SVOM = Space-based multiband astronomical Variable Objects Monitor ...
... SVOM = Space-based multiband astronomical Variable Objects Monitor ...
The Lagoon Nebula and its Vicinity
... BS 1–3: The most prominent (BS 1) corresponds to the inner core of the H II region, centred on the Hourglass (clump HG and surroundings in Fig. 6); BS 2 (SC 8 and surroundings in Fig. 6) lies at the southern edge of the nebula, coincident with the ‘South Eastern Bright Rim’ (an ionisation front erod ...
... BS 1–3: The most prominent (BS 1) corresponds to the inner core of the H II region, centred on the Hourglass (clump HG and surroundings in Fig. 6); BS 2 (SC 8 and surroundings in Fig. 6) lies at the southern edge of the nebula, coincident with the ‘South Eastern Bright Rim’ (an ionisation front erod ...
burrows_liverpool2012
... and cast of thousands report on behalf of the Swift Team: At 13:40:41 UT, the Swift Burst Alert Telescope (BAT) re-triggered on what we are tentatively calling GRB 110328A (trigger=450161). The BAT on-board calculated location is consistent with the coordinates reported for GRB 110328A (GCN Circ 118 ...
... and cast of thousands report on behalf of the Swift Team: At 13:40:41 UT, the Swift Burst Alert Telescope (BAT) re-triggered on what we are tentatively calling GRB 110328A (trigger=450161). The BAT on-board calculated location is consistent with the coordinates reported for GRB 110328A (GCN Circ 118 ...
Fundamental properties of Ana González Galán
... The aim of this thesis is to characterise a sample of High Mass X-ray Binaries (HMXBs) formed by: IGR J00370+6122, XTE J1855-026, AX J1841.0-0535 and AX J1845.0-0433. These objects are composed of pulsars (rotating neutron stars) accreting material from the wind of their supergiant companions. The X ...
... The aim of this thesis is to characterise a sample of High Mass X-ray Binaries (HMXBs) formed by: IGR J00370+6122, XTE J1855-026, AX J1841.0-0535 and AX J1845.0-0433. These objects are composed of pulsars (rotating neutron stars) accreting material from the wind of their supergiant companions. The X ...
Y.Ueda_Future_HE_Mission2006 - X
... Observations of Obscured Black Holes Yoshihiro Ueda (Department of Astronomy, Kyoto University) ...
... Observations of Obscured Black Holes Yoshihiro Ueda (Department of Astronomy, Kyoto University) ...
Hint of a transiting extended atmosphere on 55 Cancri b⋆
... (2007) called attention to the possible flux variations on the detector along the y-axis, which represent – according to this author – an incompressible uncertainty of 5% on the flux level of extended sources. We mapped the air glow along the y-axis for each HST orbit and found that systematic varia ...
... (2007) called attention to the possible flux variations on the detector along the y-axis, which represent – according to this author – an incompressible uncertainty of 5% on the flux level of extended sources. We mapped the air glow along the y-axis for each HST orbit and found that systematic varia ...
High-resolution radio emission from RCW 49/Westerlund 2
... pinpoint protostellar objects and star-forming regions. Very recently, the capabilities of the main radio interferometers have been considerably extended. The receiver bandwiths, inversely proportional to the square root of the attainable noise, have been enlarged by a factor of ten and more. We hav ...
... pinpoint protostellar objects and star-forming regions. Very recently, the capabilities of the main radio interferometers have been considerably extended. The receiver bandwiths, inversely proportional to the square root of the attainable noise, have been enlarged by a factor of ten and more. We hav ...
Neutron Stars and the Determination of the Dense Matter Equation
... A physical understanding of the behaviour of cold ultra-dense matter – at and above nuclear density – can only be achieved by the study of neutron stars. The surface thermal emission from neutron stars in quiescent low-mass X-ray binaries (qLMXBs) inside globular clusters has proven useful for that ...
... A physical understanding of the behaviour of cold ultra-dense matter – at and above nuclear density – can only be achieved by the study of neutron stars. The surface thermal emission from neutron stars in quiescent low-mass X-ray binaries (qLMXBs) inside globular clusters has proven useful for that ...
Annual Report 2006/2007
... supernova remnant Cassiopeia A (Cas A). This object is the brightest radio source in the sky, and has been created by a supernova explosion about 330 year ago. The star itself had a mass of around 20 times the mass of the sun, but by the time it exploded it must have lost most of the outer layers. T ...
... supernova remnant Cassiopeia A (Cas A). This object is the brightest radio source in the sky, and has been created by a supernova explosion about 330 year ago. The star itself had a mass of around 20 times the mass of the sun, but by the time it exploded it must have lost most of the outer layers. T ...
Astronomy 305/Frontiers in Astronomy - Fermi Gamma
... NS spin period seen in bursts ~5-10 sec, shows evidence of rapid spin down No orbital periods – not in binaries! 4 well studied systems + several other candidate systems Several SGRs are located in or near SNRs Soft gamma ray bursts are from magnetic reconnection/flaring like giant solar flares Lx = ...
... NS spin period seen in bursts ~5-10 sec, shows evidence of rapid spin down No orbital periods – not in binaries! 4 well studied systems + several other candidate systems Several SGRs are located in or near SNRs Soft gamma ray bursts are from magnetic reconnection/flaring like giant solar flares Lx = ...
H.E.S.S. observations of the binary system PSR B1259
... part of an extended multiwavelength (MWL) campaign, which included also radio, optical, X-ray and, for the first time, highenergy (HE; E > 100 MeV) observations. This paper is dedicated to the study of the H.E.S.S. results in the context of the HE observations. The detailed study of the MWL emission ...
... part of an extended multiwavelength (MWL) campaign, which included also radio, optical, X-ray and, for the first time, highenergy (HE; E > 100 MeV) observations. This paper is dedicated to the study of the H.E.S.S. results in the context of the HE observations. The detailed study of the MWL emission ...
Star Formation in the Rosette Complex
... The pioneering observations by Gosachinskii & Khersonskii (1982) of the HI emission at 21 cm made with the RATAN-600 telescope revealed that the Rosette Complex and the Monoceros Loop were enclosed in a thin HI envelope 130 pc in diameter, possibly expanding at 20 km·s−1 , suggesting that the supern ...
... The pioneering observations by Gosachinskii & Khersonskii (1982) of the HI emission at 21 cm made with the RATAN-600 telescope revealed that the Rosette Complex and the Monoceros Loop were enclosed in a thin HI envelope 130 pc in diameter, possibly expanding at 20 km·s−1 , suggesting that the supern ...
AGN surveys to study galaxy evolution along cosmic times
... “The observed line intensities [....] in NGC1068 and 4151 closely resemble the line intensities of the planetary nebula NGC7027” and “The hydrogen lines in NGC4151 and 7469 are of unusual interest, being composed of relatively narrow cores (1100 km/sec wide) superposed on very wide wings (7500 km/se ...
... “The observed line intensities [....] in NGC1068 and 4151 closely resemble the line intensities of the planetary nebula NGC7027” and “The hydrogen lines in NGC4151 and 7469 are of unusual interest, being composed of relatively narrow cores (1100 km/sec wide) superposed on very wide wings (7500 km/se ...
On the possibility of a helium white dwarf donor in the presumed
... Abstract. 2S 0918–549 is a low-mass X-ray binary (LMXB) with a low optical to X-ray flux ratio. Probably it is an ultracompact binary with an orbital period shorter than 60 min. Such binaries cannot harbor hydrogen rich donor stars. As with other (sometimes confirmed) ultracompact LMXBs, 2S 0918–549 ...
... Abstract. 2S 0918–549 is a low-mass X-ray binary (LMXB) with a low optical to X-ray flux ratio. Probably it is an ultracompact binary with an orbital period shorter than 60 min. Such binaries cannot harbor hydrogen rich donor stars. As with other (sometimes confirmed) ultracompact LMXBs, 2S 0918–549 ...
Section IV High-Energy Astrophysics and Cosmology
... presents the main basis for modern science of the polarized emission of cosmic objects including X-rays and gamma-rays. The accreting supermassive black holes (SMBH) in active galactic nuclei (AGN) are found in the center of modern astrophysics. The main problem is connected with determining the mas ...
... presents the main basis for modern science of the polarized emission of cosmic objects including X-rays and gamma-rays. The accreting supermassive black holes (SMBH) in active galactic nuclei (AGN) are found in the center of modern astrophysics. The main problem is connected with determining the mas ...
THE SOFT STATE OF CYGNUS X-1 OBSERVED WITH
... considerations. For the reflected emission, we use the XILLVER reflection model because it incorporates the effects of viewing angle (i.e., the disk inclination, i) on the observed reflection spectrum. We use the combination of XILLVER and RELCONV to remain consistent with the approach of Tomsick et al ...
... considerations. For the reflected emission, we use the XILLVER reflection model because it incorporates the effects of viewing angle (i.e., the disk inclination, i) on the observed reflection spectrum. We use the combination of XILLVER and RELCONV to remain consistent with the approach of Tomsick et al ...
POSTERS SESSION I: Atmospheres of Massive Stars
... Massive stars have strong stellar winds that exhibit variability on timescales ranging from hours to years. Many classes of these stars are also seen, via photometric or line-profile variability, to pulsate radially or nonradially. It has been suspected for some time that these oscillations can indu ...
... Massive stars have strong stellar winds that exhibit variability on timescales ranging from hours to years. Many classes of these stars are also seen, via photometric or line-profile variability, to pulsate radially or nonradially. It has been suspected for some time that these oscillations can indu ...
Neutron stars: the densest state of condensed matter
... In 1967, Iosif Shklovsky correctly proposed that Scorpius X-1 (found in 1962) is a neutron star accreting matter from a normal star. But its work attracted little attention among astrophysicists. ...
... In 1967, Iosif Shklovsky correctly proposed that Scorpius X-1 (found in 1962) is a neutron star accreting matter from a normal star. But its work attracted little attention among astrophysicists. ...
Chapter 4 On the possibility of a helium white dwarf donor in the
... in the flash fuel. The question is: where does the hydrogen and helium come from if not from the donor star? The problem is more severe for hydrogen than for helium because in an evolved donor star like in an ultracompact system the hydrogen can reside only in the outer layers that were lost being o ...
... in the flash fuel. The question is: where does the hydrogen and helium come from if not from the donor star? The problem is more severe for hydrogen than for helium because in an evolved donor star like in an ultracompact system the hydrogen can reside only in the outer layers that were lost being o ...
SKA and VLBI synergies
... VLBI observations have remarkably strong impact in the Stellar physics studies. We can mention the study of Gamma Ray Bursts (GRBs), Radio Supernovae (RSNe) and Supernova Remnants (SNRs), Microquasars or Pulsars, among others. Moreover, VLBI astrometry is a unique tool providing stellar parallax mea ...
... VLBI observations have remarkably strong impact in the Stellar physics studies. We can mention the study of Gamma Ray Bursts (GRBs), Radio Supernovae (RSNe) and Supernova Remnants (SNRs), Microquasars or Pulsars, among others. Moreover, VLBI astrometry is a unique tool providing stellar parallax mea ...
Symbiotic Stars as Laboratories for the Study of
... Abstract Symbiotic binary stars typically consist of a white dwarf (WD) that accretes material from the wind of a companion red giant. Orbital periods for these binaries are on the order of years, and their relatively small optical outbursts tend to occur every few years to decades. In some symbioti ...
... Abstract Symbiotic binary stars typically consist of a white dwarf (WD) that accretes material from the wind of a companion red giant. Orbital periods for these binaries are on the order of years, and their relatively small optical outbursts tend to occur every few years to decades. In some symbioti ...
X-ray narrow emission lines from the nuclear region of NGC 1365
... analyse and characterise in a uniform way the soft X-ray narrow-line emitting gas in the nucleus. Aims. We characterise the narrow-line emitting gas visible by XMM-Newton RGS and make comparisons between the 2012–13 spectra and those from 2004–07, already published. Methods. This source is usually a ...
... analyse and characterise in a uniform way the soft X-ray narrow-line emitting gas in the nucleus. Aims. We characterise the narrow-line emitting gas visible by XMM-Newton RGS and make comparisons between the 2012–13 spectra and those from 2004–07, already published. Methods. This source is usually a ...
GRB – The Afterglow
... Both progenitor types result in the formation of a few solar mass BH, surrounded by a torus whose accretion can provide a sudden release of energy, sufficient to power a burst. But different natural timescales imply different burst durations: LONG: death of massive stars free-fall time of the ma ...
... Both progenitor types result in the formation of a few solar mass BH, surrounded by a torus whose accretion can provide a sudden release of energy, sufficient to power a burst. But different natural timescales imply different burst durations: LONG: death of massive stars free-fall time of the ma ...
The X-ray emission from shock cooling zones in O star winds
... Hillier et al. achieved a reasonable fit to the observations with the assumption that all shocks were characterized by a single temperature of log T [K] ≈ 6.60 (see their Fig. 2). But the flux deficiency in the calculated spectrum for energies below 0.45 keV indicated that a cooler shock component o ...
... Hillier et al. achieved a reasonable fit to the observations with the assumption that all shocks were characterized by a single temperature of log T [K] ≈ 6.60 (see their Fig. 2). But the flux deficiency in the calculated spectrum for energies below 0.45 keV indicated that a cooler shock component o ...
X-ray astronomy
X-ray astronomy is an observational branch of astronomy which deals with the study of X-ray observation and detection from astronomical objects. X-radiation is absorbed by the Earth's atmosphere, so instruments to detect X-rays must be taken to high altitude by balloons, sounding rockets, and satellites. X-ray astronomy is the space science related to a type of space telescope that can see farther than standard light-absorption telescopes, such as the Mauna Kea Observatories, via x-ray radiation.X-ray emission is expected from astronomical objects that contain extremely hot gasses at temperatures from about a million kelvin (K) to hundreds of millions of kelvin (MK). Although X-rays have been observed emanating from the Sun since the 1940s, the discovery in 1962 of the first cosmic X-ray source was a surprise. This source is called Scorpius X-1 (Sco X-1), the first X-ray source found in the constellation Scorpius. The X-ray emission of Scorpius X-1 is 10,000 times greater than its visual emission, whereas that of the Sun is about a million times less. In addition, the energy output in X-rays is 100,000 times greater than the total emission of the Sun in all wavelengths. Based on discoveries in this new field of X-ray astronomy, starting with Scorpius X-1, Riccardo Giacconi received the Nobel Prize in Physics in 2002. It is now known that such X-ray sources as Sco X-1 are compact stars, such as neutron stars or black holes. Material falling into a black hole may emit X-rays, but the black hole itself does not. The energy source for the X-ray emission is gravity. Infalling gas and dust is heated by the strong gravitational fields of these and other celestial objects.Many thousands of X-ray sources are known. In addition, the space between galaxies in galaxy clusters is filled with a very hot, but very dilute gas at a temperature between 10 and 100 megakelvins (MK). The total amount of hot gas is five to ten times the total mass in the visible galaxies.