Supermassive black hole activity in local field early
... Investigate highly sub-Eddington (Lx/Ledd<1e-5) activity in local super-massive BHs Quantify active fraction as a function of BH/host mass, corrected for ‘Eddington incompleteness’ Constrain the local BH occupation fraction Control for environmental effects on the nuclear activity (cluster m ...
... Investigate highly sub-Eddington (Lx/Ledd<1e-5) activity in local super-massive BHs Quantify active fraction as a function of BH/host mass, corrected for ‘Eddington incompleteness’ Constrain the local BH occupation fraction Control for environmental effects on the nuclear activity (cluster m ...
Today in Astronomy 102: observations of stellar
... of the principal signatures of a black hole because it is hard for ordinary astronomical objects to emit X rays. Search for such objects near visible stars. Most stars have stellar companions; if such a companion became a black hole, and the two were close enough together, material from the visibl ...
... of the principal signatures of a black hole because it is hard for ordinary astronomical objects to emit X rays. Search for such objects near visible stars. Most stars have stellar companions; if such a companion became a black hole, and the two were close enough together, material from the visibl ...
Blowing Bubbles in Space: The Birth and Death of Practically
... • Planetary nebulae are the final stages in the lives of low-mass stars, such as our Sun. As they reach the ends of their lives, their late RGB superwinds send off large amounts of material into space. Although the nebulae can look like a fireworks display, the process of developing a nebula is (usu ...
... • Planetary nebulae are the final stages in the lives of low-mass stars, such as our Sun. As they reach the ends of their lives, their late RGB superwinds send off large amounts of material into space. Although the nebulae can look like a fireworks display, the process of developing a nebula is (usu ...
Strongly Interacting Supernovae - The National Centre for Radio
... Column density is a factor 50 smaller (1.3E21) than needed to produce the X-ray luminosity (4E22). ...
... Column density is a factor 50 smaller (1.3E21) than needed to produce the X-ray luminosity (4E22). ...
JOINT DISCUSSION mirror which reflects the light of the primary
... United States. The institutions now involved are the U.S. Naval Research Laboratory, the Air Force Cambridge Research Center, and the University of Colorado. The overall program has many objectives. From the point of view of astrophysics the objective is to uncover the solar spectrum to the very sho ...
... United States. The institutions now involved are the U.S. Naval Research Laboratory, the Air Force Cambridge Research Center, and the University of Colorado. The overall program has many objectives. From the point of view of astrophysics the objective is to uncover the solar spectrum to the very sho ...
Letter to the Editor - Max-Planck
... emission. In Cygnus X-1, strong reflection features indicate coronal emission in the X-ray band, but the jet emission may emerge in the gamma-ray band. The absence of reflection features in the spectra of the ultraluminous compact X-ray sources in nearby galaxies suggests that they are dominated by ...
... emission. In Cygnus X-1, strong reflection features indicate coronal emission in the X-ray band, but the jet emission may emerge in the gamma-ray band. The absence of reflection features in the spectra of the ultraluminous compact X-ray sources in nearby galaxies suggests that they are dominated by ...
Brown Dwarfs and M Dwarfs
... • BDs have cool neutral atmospheres → magnetic fields have little free energy in the photosphere → low heating rate for the corona. • Coronae are cooler with small pressure scale heights and low densities. Coronal magnetic field reconnections likely occur where density very low. (Extremely low β.) • ...
... • BDs have cool neutral atmospheres → magnetic fields have little free energy in the photosphere → low heating rate for the corona. • Coronae are cooler with small pressure scale heights and low densities. Coronal magnetic field reconnections likely occur where density very low. (Extremely low β.) • ...
Lecture 2. Isolated Neutron Stars – I.
... The satellite was launched on December 12, 1970. The program was ended in March 1973. The other name SAS-1 2-20 keV The first full sky survey. 339 sources. ...
... The satellite was launched on December 12, 1970. The program was ended in March 1973. The other name SAS-1 2-20 keV The first full sky survey. 339 sources. ...
High energy universe – Satellite missions
... Associated with acceleration of charged particles is the emission of radiation. The standard radiation processes are the bremsstrahlung, synchrotron and the inverse Compton and the Raman scattering. Often a combination of these processes is used to account for the observed radiation spectrum as for ...
... Associated with acceleration of charged particles is the emission of radiation. The standard radiation processes are the bremsstrahlung, synchrotron and the inverse Compton and the Raman scattering. Often a combination of these processes is used to account for the observed radiation spectrum as for ...
First generation stars
... • Two density scales where primordial gas collapse may slow down. • 1) n_h~10^4 cc where LTE level population are achieved. Fragmentation mass scale ~100 solar masses. • 2) n_h>10^12 cc where gas become optical to H2 lines. Fragmentation mass scale <= 1-2 solar masses. ...
... • Two density scales where primordial gas collapse may slow down. • 1) n_h~10^4 cc where LTE level population are achieved. Fragmentation mass scale ~100 solar masses. • 2) n_h>10^12 cc where gas become optical to H2 lines. Fragmentation mass scale <= 1-2 solar masses. ...
Activity: Multiwavelength Bingo - Chandra X
... objects in the Universe comes from studying the light that is emitted or reflected by them. The entire range of energies of light is called the electromagnetic spectrum. Our eyes are sensitive only to a narrow band of electromagnetic radiation called visible light, but luckily NASAʼs great observato ...
... objects in the Universe comes from studying the light that is emitted or reflected by them. The entire range of energies of light is called the electromagnetic spectrum. Our eyes are sensitive only to a narrow band of electromagnetic radiation called visible light, but luckily NASAʼs great observato ...
AMUSE-Virgo on the survival of super
... AMUSE-Virgo: latest results 26/100 nuclear super-massive Point-like nuclearX-ray X-raysources source likley detected in 32p/100 black objectsholes ...
... AMUSE-Virgo: latest results 26/100 nuclear super-massive Point-like nuclearX-ray X-raysources source likley detected in 32p/100 black objectsholes ...
The Milky Way at Different Wavelengths
... images are in Galactic coordinates with the direction of the Galactic center in the center of each. For scale, the vertical dimension of each image is forty times the angular diameter of the full moon on the sky; the areas shown represent about one-sixth of the entire sky. Radio Continuum (ν = 408 M ...
... images are in Galactic coordinates with the direction of the Galactic center in the center of each. For scale, the vertical dimension of each image is forty times the angular diameter of the full moon on the sky; the areas shown represent about one-sixth of the entire sky. Radio Continuum (ν = 408 M ...
Cosmic Feedback from Supermassive Black Holes
... Mechanical feedback dominates in galaxies, groups, and clusters at late times, as shown by X-ray observations of gas in the bulges of massive galaxies and the cores of galaxy clusters (eg., Fig. 1). The energy transfer process is surprisingly subtle. The radiative cooling time of the hot gas in thes ...
... Mechanical feedback dominates in galaxies, groups, and clusters at late times, as shown by X-ray observations of gas in the bulges of massive galaxies and the cores of galaxy clusters (eg., Fig. 1). The energy transfer process is surprisingly subtle. The radiative cooling time of the hot gas in thes ...
Can we determine the grain composition of the Interstellar Medium with
... Isolated Atom: Bound free process --> edge step Isolated Atom : Bound bound process --> inner shell resonance absorption lines (e.g. MCG-6-30-15: Oxygen V, VI KLL : Lee et al. 2001; IRAS 13349 : 2p-3d M-shell Fe : Sako et al. 2000, NGC 3783 -- Kaspi et al. 2002, Netzer et al. 2003 & references there ...
... Isolated Atom: Bound free process --> edge step Isolated Atom : Bound bound process --> inner shell resonance absorption lines (e.g. MCG-6-30-15: Oxygen V, VI KLL : Lee et al. 2001; IRAS 13349 : 2p-3d M-shell Fe : Sako et al. 2000, NGC 3783 -- Kaspi et al. 2002, Netzer et al. 2003 & references there ...
HEA_Accretion_2003_04
... • Primary accretes material with angular momentum => primary spins-up (rather than spin-down as observed in pulsars) • Rate of spin-up consistent with neutron star primary (white dwarf would be slower) • Cen X-3 ‘classical’ X-ray pulsator ...
... • Primary accretes material with angular momentum => primary spins-up (rather than spin-down as observed in pulsars) • Rate of spin-up consistent with neutron star primary (white dwarf would be slower) • Cen X-3 ‘classical’ X-ray pulsator ...
this paper
... incoming X-rays so that the dispersion is matched to laterally graded multilayer (ML) coated reflectors. An extension of this approach was suggested by Marshall (20082 ) that can be used with larger missions such as the AXSIO or AEGIS. Some potential scientific investigations that would be possible ...
... incoming X-rays so that the dispersion is matched to laterally graded multilayer (ML) coated reflectors. An extension of this approach was suggested by Marshall (20082 ) that can be used with larger missions such as the AXSIO or AEGIS. Some potential scientific investigations that would be possible ...
Ten Years Of XMM-Newton: Scientific Achievements And Future Prospects Norbert Schartel
... densest and hottest parts of the warm-hot intergalactic medium ...
... densest and hottest parts of the warm-hot intergalactic medium ...
AAS_WFXT_Solar_System_11Jan2010
... study. Most objects have been detected with only a few photons. • There is an important list of solar system objects that have yet to be detected in the x-ray : Mercury, the ice giants Uranus/Neptune, the Main Belt comets,KBOs, and the heliopause. • Large Scale WFXT Imaging will allow for direct, co ...
... study. Most objects have been detected with only a few photons. • There is an important list of solar system objects that have yet to be detected in the x-ray : Mercury, the ice giants Uranus/Neptune, the Main Belt comets,KBOs, and the heliopause. • Large Scale WFXT Imaging will allow for direct, co ...
Very Low Mass Stars as Optimum Sites of Habitable Planets
... atmospheric retention will occur in synchronously rotating planets for atmospheres thicker than about 30 mb, low-mass stars should be the most common site for habitable planets interesting radiation environment! Flare rate as function of flare energy in U band known for about 30 dMe stars, consist ...
... atmospheric retention will occur in synchronously rotating planets for atmospheres thicker than about 30 mb, low-mass stars should be the most common site for habitable planets interesting radiation environment! Flare rate as function of flare energy in U band known for about 30 dMe stars, consist ...
Accretion
... releases energy into the disk atmosphere – mostly in X-rays • The magnetic field also transfers angular momentum out of the disk system ...
... releases energy into the disk atmosphere – mostly in X-rays • The magnetic field also transfers angular momentum out of the disk system ...
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.