PDF only - at www.arxiv.org.
... the current techniques for X-ray focusing (to date, adopted only below 10 keV) to the hard (E > 10 keV) X-ray band by adopting very shallow incidence angles (0.1 ÷ 0.4 deg) and graded multilayer coatings5,6. For example, the SIMBOL-X sensitivity band is 0.5 ÷ 80 keV, with a required angular resoluti ...
... the current techniques for X-ray focusing (to date, adopted only below 10 keV) to the hard (E > 10 keV) X-ray band by adopting very shallow incidence angles (0.1 ÷ 0.4 deg) and graded multilayer coatings5,6. For example, the SIMBOL-X sensitivity band is 0.5 ÷ 80 keV, with a required angular resoluti ...
On the nature of the stellar-mass black-hole candidate X
... 1.1 X-ray binary star systems X-ray binary systems are binary star systems that are very luminous in the X-ray part of the spectrum. They emit in the X-ray region because it is believed that one of the components is a compact object accreting matter from the other star. The compact object can either ...
... 1.1 X-ray binary star systems X-ray binary systems are binary star systems that are very luminous in the X-ray part of the spectrum. They emit in the X-ray region because it is believed that one of the components is a compact object accreting matter from the other star. The compact object can either ...
PDF document
... Another proposed signature of a NS-NS/NS-BH binary merger is the production of a socalled “kilonova” (sometimes also termed a “macronova” or ”mini-supernova”) due to the decay of radioactive species produced and initially ejected during the merger process – in other words, an event similar to a fain ...
... Another proposed signature of a NS-NS/NS-BH binary merger is the production of a socalled “kilonova” (sometimes also termed a “macronova” or ”mini-supernova”) due to the decay of radioactive species produced and initially ejected during the merger process – in other words, an event similar to a fain ...
Radio-loud ROSAT sources near the North Ecliptic Pole
... (CalTech). The catalog was created through a collaboration between the Naval Research Laboratory (NRL) and the Royal Observatory, Edinburgh (ROE) in support of the ROSAT mission (Yentis et al. 1992). Three blue (IIIa-J and GG395 filter) plates (PSIIJ071, PSIIJ102, and PSIIJ103) and two red (IIIa-F a ...
... (CalTech). The catalog was created through a collaboration between the Naval Research Laboratory (NRL) and the Royal Observatory, Edinburgh (ROE) in support of the ROSAT mission (Yentis et al. 1992). Three blue (IIIa-J and GG395 filter) plates (PSIIJ071, PSIIJ102, and PSIIJ103) and two red (IIIa-F a ...
X-ray telescopes
... rocket flight ushered in the era of solar x-ray research. The first x-ray picture of the Sun was obtained in 1960 with a pinhole camera experiment, again on a sounding rocket flight (Chubb et a1 1961). In 1960 Giacconi and Rossi pointed out that future x-ray astronomy would greatly benefit from the ...
... rocket flight ushered in the era of solar x-ray research. The first x-ray picture of the Sun was obtained in 1960 with a pinhole camera experiment, again on a sounding rocket flight (Chubb et a1 1961). In 1960 Giacconi and Rossi pointed out that future x-ray astronomy would greatly benefit from the ...
CORONAL EVOLUTION OF THE SUN IN TIME: HIGH
... this picture, the flare rate is responsible both for bringing dense material into the corona and for heating it to high temperatures, analogous to the behavior of individual flares observed on the Sun. A large flare rate in younger stars with a higher magnetic filling factor could thus produce X-ray ...
... this picture, the flare rate is responsible both for bringing dense material into the corona and for heating it to high temperatures, analogous to the behavior of individual flares observed on the Sun. A large flare rate in younger stars with a higher magnetic filling factor could thus produce X-ray ...
3011800000360
... both models, as the irradiation has no significant effect on the disk midplane temperatures. In the hydrogen disk models employed to account for the observed outbursts of dwarf novae and soft X-ray transients, the disk has two states. The viscosity parameter is large (small) when the effective tem ...
... both models, as the irradiation has no significant effect on the disk midplane temperatures. In the hydrogen disk models employed to account for the observed outbursts of dwarf novae and soft X-ray transients, the disk has two states. The viscosity parameter is large (small) when the effective tem ...
The extreme ultraviolet and X-ray Sun in Time: High
... in the first 20 Myr. This might cause us to underestimate the age by a few Myr when stars on the 10th percentile track come out of saturation. Figure 2b shows predicted tracks for LX and LEUV together with observed LX for stars in the 0.9−1.1 M range for each cluster listed in Sect. 3. Because of t ...
... in the first 20 Myr. This might cause us to underestimate the age by a few Myr when stars on the 10th percentile track come out of saturation. Figure 2b shows predicted tracks for LX and LEUV together with observed LX for stars in the 0.9−1.1 M range for each cluster listed in Sect. 3. Because of t ...
The Be/X-ray transient 4U 0115+ 63/V635 Cassiopeiae
... The peak separation corresponds to ∆vpeak ≈ 600 km s−1 , well above what would be seen in the case of angular momentum conservation. The strong narrow features are interstellar diffuse bands. The spectra were divided by a spline fit to the continuum for normalisation ...
... The peak separation corresponds to ∆vpeak ≈ 600 km s−1 , well above what would be seen in the case of angular momentum conservation. The strong narrow features are interstellar diffuse bands. The spectra were divided by a spline fit to the continuum for normalisation ...
THE MYSTERIOUS SICKLE OBJECT IN THE CARINA NEBULA: A
... Optical and near-infrared images of the Carina Nebula show a peculiar arc-shaped feature, which we call the ”Sickle”, next to the B-type star Trumpler 14 MJ 218. We use multi-wavelength observations to explore and constrain the nature and origin of the nebulosity. Using sub-mm data from APEX/LABOCA ...
... Optical and near-infrared images of the Carina Nebula show a peculiar arc-shaped feature, which we call the ”Sickle”, next to the B-type star Trumpler 14 MJ 218. We use multi-wavelength observations to explore and constrain the nature and origin of the nebulosity. Using sub-mm data from APEX/LABOCA ...
Optical Variability of Hercules X-1/HZ Herculis
... present some earlier results on X-ray and optical variabilities (35d and 1.7d cycle). In section IV results obtained from the optical observations at McDonald Observatory in June, 2001 are presented. We will use Fourier methods to study the power spectral density (PSD) of the recorded light curves a ...
... present some earlier results on X-ray and optical variabilities (35d and 1.7d cycle). In section IV results obtained from the optical observations at McDonald Observatory in June, 2001 are presented. We will use Fourier methods to study the power spectral density (PSD) of the recorded light curves a ...
Present Carbon and Oxygen data with efficiency numbers
... The Constellation-X mission will provide an instrument with large effective collecting area and high spectral resolution relative to past and current x-ray observatories. An overview of the mission and science goals is given by Tananbaum, et al.1, and can be found on the web at http://constellation. ...
... The Constellation-X mission will provide an instrument with large effective collecting area and high spectral resolution relative to past and current x-ray observatories. An overview of the mission and science goals is given by Tananbaum, et al.1, and can be found on the web at http://constellation. ...
Massive close binaries, observational characteristics - UvA-DARE
... from mass-exchange binaries in which the original primary star has exploded as a supemova. Many of them might well have an unseen compact companion star (see especially also Stone, 1991). Alternatively if large asymmetries in the SN mass ejection occur (see next section), it is also possible that a ...
... from mass-exchange binaries in which the original primary star has exploded as a supemova. Many of them might well have an unseen compact companion star (see especially also Stone, 1991). Alternatively if large asymmetries in the SN mass ejection occur (see next section), it is also possible that a ...
Demonstration of multilayer reflective optics at photon energies
... The specular reflectivity data at 0.51 MeV and 0.65 MeV are shown in Figure 3. The reflectivity was modeled using the IDL software package IMD [23]. IMD implements the Fresnel equations, including Névot-Croce factors to account for interface imperfections. Additional custom software was written to ...
... The specular reflectivity data at 0.51 MeV and 0.65 MeV are shown in Figure 3. The reflectivity was modeled using the IDL software package IMD [23]. IMD implements the Fresnel equations, including Névot-Croce factors to account for interface imperfections. Additional custom software was written to ...
ABSTRACT XMM-Newton X-Ray Spectroscopy of the B2 Bright Giant
... to thousands of kilometers per second, within a few stellar radii of the surface. The wind of a lORe,) star can be accelerated to its terminal velocity of 2000 km s-l in 10 4 seconds, with about 10 7 photons scattering off each ion per second (Lamers & Cassinelli 1999). It is possible for the wind t ...
... to thousands of kilometers per second, within a few stellar radii of the surface. The wind of a lORe,) star can be accelerated to its terminal velocity of 2000 km s-l in 10 4 seconds, with about 10 7 photons scattering off each ion per second (Lamers & Cassinelli 1999). It is possible for the wind t ...
eROSITA Mission Definition Document
... Most of the light created after the «dark ages» in the Universe comes from active centres of galaxies, emitted either by vigorous star formation processes or by prodigious supermassive black holes residing in the centre of almost every galaxy, swallowing stars and gas. It was only realized in recent ...
... Most of the light created after the «dark ages» in the Universe comes from active centres of galaxies, emitted either by vigorous star formation processes or by prodigious supermassive black holes residing in the centre of almost every galaxy, swallowing stars and gas. It was only realized in recent ...
ppt - chris.engelbrecht.nithep.ac.za
... radius of 22 arcseconds at the 60 kpc distance of the SMC. The spectrum of the blast wave yields a temperature of kTx 0.8 keV and an ionization timescale n e t ~ 11011 cm3s . 1. Based on the temperature, what is the shock velocity? Assuming the SNR is calculate the age. How does this compare ...
... radius of 22 arcseconds at the 60 kpc distance of the SMC. The spectrum of the blast wave yields a temperature of kTx 0.8 keV and an ionization timescale n e t ~ 11011 cm3s . 1. Based on the temperature, what is the shock velocity? Assuming the SNR is calculate the age. How does this compare ...
X-ray Binaries
... of the neutron star mass distribution in HMXBs are found to agree with theoretical expectations of core-collapse supernovae [60]. Constraints on neutron star forming supernovae do seem to be provided by two distinct populations of X-ray pulsars in Be/X-ray binaries; short Pspin pulsars with short or ...
... of the neutron star mass distribution in HMXBs are found to agree with theoretical expectations of core-collapse supernovae [60]. Constraints on neutron star forming supernovae do seem to be provided by two distinct populations of X-ray pulsars in Be/X-ray binaries; short Pspin pulsars with short or ...
Conceptual Design of the International Axion Observatory (IAXO)
... A third-generation experiment, the CERN Axion Solar Telescope (CAST), began data collection in 2003. The experiment uses a Large Hadron Collider (LHC) dipole prototype magnet with a magnetic field of up to 9 T over a length of 9.3 m [25]. Like Sumico, CAST is able to follow the Sun for several hours ...
... A third-generation experiment, the CERN Axion Solar Telescope (CAST), began data collection in 2003. The experiment uses a Large Hadron Collider (LHC) dipole prototype magnet with a magnetic field of up to 9 T over a length of 9.3 m [25]. Like Sumico, CAST is able to follow the Sun for several hours ...
Neutron Stars - Lick Observatory
... increase with accretion but with almost constant frequency difference. The pair is most likely the orbital frequency of accreting matter in Keplerian orbits around the neutron star and its beat frequency with the neutron star spin. In the case of 4U 1820-30 the accretion may have been tracked to its ...
... increase with accretion but with almost constant frequency difference. The pair is most likely the orbital frequency of accreting matter in Keplerian orbits around the neutron star and its beat frequency with the neutron star spin. In the case of 4U 1820-30 the accretion may have been tracked to its ...
ppt - SLAC
... 1. Black-body temperature sets the star's color and determines its surface brightness: 2. Atmospheric pressure depends on the star's surface gravity and so, roughly, on its size —a giant, dwarf, or in between. The size and surface brightness yield the star's luminosity and often its evolutionary sta ...
... 1. Black-body temperature sets the star's color and determines its surface brightness: 2. Atmospheric pressure depends on the star's surface gravity and so, roughly, on its size —a giant, dwarf, or in between. The size and surface brightness yield the star's luminosity and often its evolutionary sta ...
GRB 130603B: No Compelling Evidence for Neutron Star Merger
... [30, 31], and a late-time flare produced by collision of the SHB jet with an ISM density bump [8, 18]. SHBs plus a minisupernova/macronova/kilonova, however, are not unique to the neutron star merger scenario. They can be produced also in a phase transition/collapse of single compact stars (neutron ...
... [30, 31], and a late-time flare produced by collision of the SHB jet with an ISM density bump [8, 18]. SHBs plus a minisupernova/macronova/kilonova, however, are not unique to the neutron star merger scenario. They can be produced also in a phase transition/collapse of single compact stars (neutron ...
High energy processes in young stellar objects and high-mass X
... 4.2 Fermi observational data . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 Fermi /LAT data analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.5 Discussion . . . . . . . . . . . . . . . ...
... 4.2 Fermi observational data . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 Fermi /LAT data analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.5 Discussion . . . . . . . . . . . . . . . ...
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.