Hidden57_rf
... of images using three different wavebands of light. Infrared data from the Spitzer Space Telescope are coloured red; visible data from the Hubble Space Telescope are yellow; and X-ray data from the Chandra X-ray Observatory are green and blue. Located 10,000 light-years away in the constellation Cas ...
... of images using three different wavebands of light. Infrared data from the Spitzer Space Telescope are coloured red; visible data from the Hubble Space Telescope are yellow; and X-ray data from the Chandra X-ray Observatory are green and blue. Located 10,000 light-years away in the constellation Cas ...
A Universe of Disks
... experiments to search for turbulence in flows that resemble accretion disks, but again the results have been debated. Although turbulence is sometimes seen in these experiments, it may arise from effects that would not be present in a real accretion disk. Nevertheless, astrophysicists have persisted ...
... experiments to search for turbulence in flows that resemble accretion disks, but again the results have been debated. Although turbulence is sometimes seen in these experiments, it may arise from effects that would not be present in a real accretion disk. Nevertheless, astrophysicists have persisted ...
Laboratory Title: The Glittery Milky Way
... entire celestial sphere and originating from stars and other material that lie within the galactic plane. The stellar disk of the Milky Way galaxy is approximately 100,000 light-years (9.5×1017 km) in diameter, and is believed to be, on average, about 1,000 light years (9.5×1015 km) thick. It is est ...
... entire celestial sphere and originating from stars and other material that lie within the galactic plane. The stellar disk of the Milky Way galaxy is approximately 100,000 light-years (9.5×1017 km) in diameter, and is believed to be, on average, about 1,000 light years (9.5×1015 km) thick. It is est ...
SOLAR HARD X-RAY AND GAMMA-RAY OBSERVATIONS FROM
... accelerated during solar flares. Since the beginning of 1990 the PHEBUS instrument and the SIGMA anticoincidence shield aboard GRANAT have provided hard X-ray and gamma-ray observations of solar bursts in the energy range 0.075-124 and 0.200-15 MeV, respectively. After a brief description of the exp ...
... accelerated during solar flares. Since the beginning of 1990 the PHEBUS instrument and the SIGMA anticoincidence shield aboard GRANAT have provided hard X-ray and gamma-ray observations of solar bursts in the energy range 0.075-124 and 0.200-15 MeV, respectively. After a brief description of the exp ...
Document
... β- and β+ decays may occur from excited isomeric states maintained in equilibrium with ground state by radiative transitions electron-capture rates are affected by temperature and density through population of the K electronic shell ...
... β- and β+ decays may occur from excited isomeric states maintained in equilibrium with ground state by radiative transitions electron-capture rates are affected by temperature and density through population of the K electronic shell ...
RAPID MASS ACCRETION IN THE SYMBIOTIC STAR AG DRA T
... The temperature of the hot component of AG Dra in the quiescent stage is about 150000 K which is derived from the intensities of He H 4686 and He 14471 relative to Hg obtained on August 5, 1980 (Blair et al., 1983) using the formula of Iijima (1982). The luminosity of the hot component in the ultrav ...
... The temperature of the hot component of AG Dra in the quiescent stage is about 150000 K which is derived from the intensities of He H 4686 and He 14471 relative to Hg obtained on August 5, 1980 (Blair et al., 1983) using the formula of Iijima (1982). The luminosity of the hot component in the ultrav ...
... per cubic light-year, are arranged in an elongated structure about 1000 light-years across • Some energetic event, perhaps a supernova explosion, violently disturbed the center in the not-to-distant past • Deep within the core lies an incredibly small (10 AU diameter) radio source known as Sgr A* • ...
Sample pages 1 PDF
... geometrically thick flow with the aspect ratio of H/R∼0.5–1. The soft (optically thick) and hard (optically thin) spectral components are formed in the accretion disk and the hot inner flow correspondingly. The value of the truncation radius can be inferred from the observations. Although their inte ...
... geometrically thick flow with the aspect ratio of H/R∼0.5–1. The soft (optically thick) and hard (optically thin) spectral components are formed in the accretion disk and the hot inner flow correspondingly. The value of the truncation radius can be inferred from the observations. Although their inte ...
Sterrenstelsels en Cosmologie Docent: M. Franx, kamer 425
... •Very good dynamic range Photometry −> Imaging galaxies and measuring their brightness distribution •Big technical problem: galaxies are really large, and have low surface brightness wings. See the beautiful image of M31 ...
... •Very good dynamic range Photometry −> Imaging galaxies and measuring their brightness distribution •Big technical problem: galaxies are really large, and have low surface brightness wings. See the beautiful image of M31 ...
Next Generation VLA Science White Paper
... The last decades have seen enormous advances in our knowledge of interstellar medium structure in the Milky Way and other galaxies, and with it a better understanding of how stars are born and galaxies grow and die. However, these have come largely from bulk tracers of interstellar gas — tools like ...
... The last decades have seen enormous advances in our knowledge of interstellar medium structure in the Milky Way and other galaxies, and with it a better understanding of how stars are born and galaxies grow and die. However, these have come largely from bulk tracers of interstellar gas — tools like ...
A Study of the Nature and Representative Features of Supernova
... closely related (Moore D. 2001). A brief description of each type follows. Type Ia Exhibit no hydrogen or helium lines but show a prominent silicon (Si II) line. Believed to be caused by runaway carbon burning in a white dwarf with a binary companion, from which the required matter to cause the expl ...
... closely related (Moore D. 2001). A brief description of each type follows. Type Ia Exhibit no hydrogen or helium lines but show a prominent silicon (Si II) line. Believed to be caused by runaway carbon burning in a white dwarf with a binary companion, from which the required matter to cause the expl ...
ISOCAM 4 m imaging of the nuclear starburst in M83
... the dust thermal emission; c) near- and mid-IR radiations give complementary information on the stellar photospheric emission and on the nebular emission from the ionized gas. Imaging at a good angular resolution is needed to establish the potential link between the different components that may be ...
... the dust thermal emission; c) near- and mid-IR radiations give complementary information on the stellar photospheric emission and on the nebular emission from the ionized gas. Imaging at a good angular resolution is needed to establish the potential link between the different components that may be ...
The X-ray/radio and UV luminosity expected from symbiotic systems
... Context. Symbiotic systems (i.e. a white dwarf + red giant star, WD + RG), which experience mass loss and form circumstellar material (CSM), have been suggested as being a possible progenitor system of type Ia supernovae (SNe Ia). After a supernova explosion, the supernova ejecta may interact with t ...
... Context. Symbiotic systems (i.e. a white dwarf + red giant star, WD + RG), which experience mass loss and form circumstellar material (CSM), have been suggested as being a possible progenitor system of type Ia supernovae (SNe Ia). After a supernova explosion, the supernova ejecta may interact with t ...
5 Report of the Panel on Stars and Stellar Evolution
... The science frontier for stars and stellar evolution is as close as the Sun and as distant as exploding stars at redshift 8.3. It includes understanding processes of exquisite complexity that connect the rotation of stars with their magnetic fields and areas of nearly total ignorance about phenomena ...
... The science frontier for stars and stellar evolution is as close as the Sun and as distant as exploding stars at redshift 8.3. It includes understanding processes of exquisite complexity that connect the rotation of stars with their magnetic fields and areas of nearly total ignorance about phenomena ...
Subatomic particle processes within neutron stars
... density would be 6.65 * 1014 gcm-3, which is higher than the typical density of an atomic nucleus. In an attempt to trivially exemplify this tremendous density, subjected to its value all the 5.5 billion inhabitants of the Earth could be crowded into a cube of 1 cm side length. [2] The gravity compr ...
... density would be 6.65 * 1014 gcm-3, which is higher than the typical density of an atomic nucleus. In an attempt to trivially exemplify this tremendous density, subjected to its value all the 5.5 billion inhabitants of the Earth could be crowded into a cube of 1 cm side length. [2] The gravity compr ...
Synthetic Stellar Populations Encyclopedia of Astronomy & Astrophysics eaa.iop.org Guy Worthey
... after a substantial red giant branch develops, a bit shy of a billion years of age. This is because almost all the light comes from stars near the main sequence turnoff or from post-main-sequence stars. All of these stars have nearly the same mass (because post-main-sequence lifetimes are relatively ...
... after a substantial red giant branch develops, a bit shy of a billion years of age. This is because almost all the light comes from stars near the main sequence turnoff or from post-main-sequence stars. All of these stars have nearly the same mass (because post-main-sequence lifetimes are relatively ...
The formation and evolution of galaxies
... • Overcooling leads to the formation of hundreds more small galaxies than are observed. ...
... • Overcooling leads to the formation of hundreds more small galaxies than are observed. ...
Ch17_lecture
... • A group of galaxy clusters may gravitationally attract each other into a larger structure called a supercluster – a cluster of clusters – A supercluster contains a half dozen to several dozen galaxy clusters spread over tens to hundreds of millions of light-years (The Local group belongs to the Lo ...
... • A group of galaxy clusters may gravitationally attract each other into a larger structure called a supercluster – a cluster of clusters – A supercluster contains a half dozen to several dozen galaxy clusters spread over tens to hundreds of millions of light-years (The Local group belongs to the Lo ...
Chapter 17 Galaxies Galaxies Early Observations
... • A group of galaxy clusters may gravitationally attract each other into a larger structure called a supercluster – a cluster of clusters – A supercluster contains a half dozen to several dozen galaxy clusters spread over tens to hundreds of millions of light-years (The Local group belongs to the Lo ...
... • A group of galaxy clusters may gravitationally attract each other into a larger structure called a supercluster – a cluster of clusters – A supercluster contains a half dozen to several dozen galaxy clusters spread over tens to hundreds of millions of light-years (The Local group belongs to the Lo ...
Neutron Stars
... A neutron star is the collapsed core of a massive star left behind after a supernova explosion. The original massive star contained between 8 and 25 M . (More massive stars collapse into black holes.) The remnant neutron star compresses at least 1.4M into a sphere only about 10-16 km across. This ...
... A neutron star is the collapsed core of a massive star left behind after a supernova explosion. The original massive star contained between 8 and 25 M . (More massive stars collapse into black holes.) The remnant neutron star compresses at least 1.4M into a sphere only about 10-16 km across. This ...
Galaxies
... spectrum of the star, they found something completely unexpected: the spectrum was flat with several unexpected, and totally unexplainable, emission lines. The object remained a mystery until similar but brighter object, 3C 273, was discovered in 1963. Astronomers noticed that 3C 273 had a normal sp ...
... spectrum of the star, they found something completely unexpected: the spectrum was flat with several unexpected, and totally unexplainable, emission lines. The object remained a mystery until similar but brighter object, 3C 273, was discovered in 1963. Astronomers noticed that 3C 273 had a normal sp ...
Astronomy Astrophysics The accretion environment in Vela X-1 during a flaring period using
... with a phenomenological model formed by three absorbed power laws plus three emission lines. After analysing the variations with orbital phase of the column density of each component, as well as those in the Fe and Ni fluorescence lines, we provide a physical interpretation for each spectral compone ...
... with a phenomenological model formed by three absorbed power laws plus three emission lines. After analysing the variations with orbital phase of the column density of each component, as well as those in the Fe and Ni fluorescence lines, we provide a physical interpretation for each spectral compone ...
ASPEN WORKSHOP 2003
... interaction, as in half of ULIRGS [as long as they are identified as “single galaxy”!] Simulations show that AI stays above 0.35 for about 700 Myears, but NOT for face-on HDF application: rest frame B morphologies, NICMOS extends out to z=3 Correcting for selection effects by simulating 38 nearer ga ...
... interaction, as in half of ULIRGS [as long as they are identified as “single galaxy”!] Simulations show that AI stays above 0.35 for about 700 Myears, but NOT for face-on HDF application: rest frame B morphologies, NICMOS extends out to z=3 Correcting for selection effects by simulating 38 nearer ga ...
High-Energy Emission from the PSR B1259
... ∼ 4 mCrab, corresponding to a luminosity of a few x 1034 erg/s at the distance of 2 kpc. The hard X-ray flux and spectrum detected by CGRO agrees with the X-ray emission measured by simultaneous ASCA observations. EGRET upper limits are significant, and exclude strong inverse Compton cooling in the ...
... ∼ 4 mCrab, corresponding to a luminosity of a few x 1034 erg/s at the distance of 2 kpc. The hard X-ray flux and spectrum detected by CGRO agrees with the X-ray emission measured by simultaneous ASCA observations. EGRET upper limits are significant, and exclude strong inverse Compton cooling in the ...
Galaxy Notes
... However, when slow-moving galaxies collide, they can merge into a single galaxy that is bigger than either of the original galaxies. Such mergers can produce spiral filaments of stars that can extend more than 100,000 light-years into space. All galaxies emit (give off) energy as waves of visible l ...
... However, when slow-moving galaxies collide, they can merge into a single galaxy that is bigger than either of the original galaxies. Such mergers can produce spiral filaments of stars that can extend more than 100,000 light-years into space. All galaxies emit (give off) energy as waves of visible l ...
Astrophysical X-ray source
Astrophysical X-ray sources are astronomical objects with physical properties which result in the emission of X-rays.There are a number of types of astrophysical objects which emit X-rays, from galaxy clusters, through black holes in active galactic nuclei (AGN) to galactic objects such as supernova remnants, stars, and binary stars containing a white dwarf (cataclysmic variable stars and super soft X-ray sources), neutron star or black hole (X-ray binaries). Some solar system bodies emit X-rays, the most notable being the Moon, although most of the X-ray brightness of the Moon arises from reflected solar X-rays. A combination of many unresolved X-ray sources is thought to produce the observed X-ray background. The X-ray continuum can arise from bremsstrahlung, either magnetic or ordinary Coulomb, black-body radiation, synchrotron radiation, inverse Compton scattering of lower-energy photons be relativistic electrons, knock-on collisions of fast protons with atomic electrons, and atomic recombination, with or without additional electron transitions.Furthermore, celestial entities in space are discussed as celestial X-ray sources. The origin of all observed astronomical X-ray sources is in, near to, or associated with a coronal cloud or gas at coronal cloud temperatures for however long or brief a period.