Clusters of Galaxies
... the 1960s (Friedman and Byram 1967, Bradt et al 1967) which discovered x-ray emission from the direction of the Virgo cluster, the closest cluster of galaxies. " In a paper of remarkable prescience, Felten et al 1966, attributed the detection of x-ray emission! from the Coma cluster to thermal brems ...
... the 1960s (Friedman and Byram 1967, Bradt et al 1967) which discovered x-ray emission from the direction of the Virgo cluster, the closest cluster of galaxies. " In a paper of remarkable prescience, Felten et al 1966, attributed the detection of x-ray emission! from the Coma cluster to thermal brems ...
CHAPTER 13 Neutron Stars and Black Holes Clickers
... Question 9 The equivalence between an accelerating windowless elevator in space and a stationary elevator in a gravity field is a prediction of Newton’s theory of gravity. explains why elevators don’t work in space. explains why E = mc2 is true. helps explain Einstein’s theory of gravity. e) All of ...
... Question 9 The equivalence between an accelerating windowless elevator in space and a stationary elevator in a gravity field is a prediction of Newton’s theory of gravity. explains why elevators don’t work in space. explains why E = mc2 is true. helps explain Einstein’s theory of gravity. e) All of ...
Document
... The Bondi accretion rate is ~ 3x1020 g s-1. If the Bondi flow terminates in a thin accretion disk, the luminosity expected is ~ 3x1040 erg s-1 (must of it in infrared and optical); this is far larger than the observed luminosity. ...
... The Bondi accretion rate is ~ 3x1020 g s-1. If the Bondi flow terminates in a thin accretion disk, the luminosity expected is ~ 3x1040 erg s-1 (must of it in infrared and optical); this is far larger than the observed luminosity. ...
A black hole: The ultimate space
... The horizon of a black hole When light particles (photons) are emitted from a black hole, they perform work against gravity. This work reduces the energy of the photons. The lower energy implies a red-shift. There is a sphere around a black hole called the horizon, where the photons lose all of the ...
... The horizon of a black hole When light particles (photons) are emitted from a black hole, they perform work against gravity. This work reduces the energy of the photons. The lower energy implies a red-shift. There is a sphere around a black hole called the horizon, where the photons lose all of the ...
A black hole
... How do we know about black holes ? • We can’t see a black hole directly, because light cannot escape from it. However, if a nearby star orbits around the black hole we can detect the black hole by its gravity. • The mass of a black hole is obtained from the orbit and the velocity of the visible sta ...
... How do we know about black holes ? • We can’t see a black hole directly, because light cannot escape from it. However, if a nearby star orbits around the black hole we can detect the black hole by its gravity. • The mass of a black hole is obtained from the orbit and the velocity of the visible sta ...
What is a Scientist? - Cockeysville Middle School
... Activity 2: Hierarchy of the Universe galaxy: a giant structure that contains hundreds of billions of stars planet: celestial objects made up of rock, water, gas and/or other substances that revolve around a star. solar system: a group of planets and other celestial objects that revolve around a st ...
... Activity 2: Hierarchy of the Universe galaxy: a giant structure that contains hundreds of billions of stars planet: celestial objects made up of rock, water, gas and/or other substances that revolve around a star. solar system: a group of planets and other celestial objects that revolve around a st ...
form b - University of Iowa Astrophysics
... (b) Cepheid variables change their brightness too quickly to detect at great distances. (c) Most galaxies in the universe are elliptical and don’t have Cepheid variables. (d) The luminosity of SN Type Ia explosions is much greater than Cepheid variables. (e) Cepheid variables are not found in the mo ...
... (b) Cepheid variables change their brightness too quickly to detect at great distances. (c) Most galaxies in the universe are elliptical and don’t have Cepheid variables. (d) The luminosity of SN Type Ia explosions is much greater than Cepheid variables. (e) Cepheid variables are not found in the mo ...
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 ...
Messing Up a Galaxy
... stars themselves are very rare indeed. This is because the spaces between the stars in a galaxy are typically very large compared with the stars' sizes. In our region of space, the distance from the Sun to its nearest stellar neighbour is about 29 million times the Sun's diameter! Our Milky Way Gala ...
... stars themselves are very rare indeed. This is because the spaces between the stars in a galaxy are typically very large compared with the stars' sizes. In our region of space, the distance from the Sun to its nearest stellar neighbour is about 29 million times the Sun's diameter! Our Milky Way Gala ...
PX269 Galaxies The University of Warwick
... remnant with a semi-major axis of 0.83 arcsec and a semi-minor axis of 0.62 arcsec. The ring brightened asymmetrically over a period of 340 days. Use this information to determine the distance to the Large Magellanic Cloud (LMC). c) What is the advantage of this method over other methods for determi ...
... remnant with a semi-major axis of 0.83 arcsec and a semi-minor axis of 0.62 arcsec. The ring brightened asymmetrically over a period of 340 days. Use this information to determine the distance to the Large Magellanic Cloud (LMC). c) What is the advantage of this method over other methods for determi ...
PHYSICAL PROPERTIES OF THE AXP 4U 0142+61 FROM X
... For the small window mode XMM-Newton observations, we extracted source spectra from a circle centered on the source with a radius of 3200 and the background from a source-free region with a radius of 5000 . We extracted the source region from the CC mode Chandra observation using a rectangular regio ...
... For the small window mode XMM-Newton observations, we extracted source spectra from a circle centered on the source with a radius of 3200 and the background from a source-free region with a radius of 5000 . We extracted the source region from the CC mode Chandra observation using a rectangular regio ...
PoA Examples Sheet 3
... The intrinsic colours of main sequence stars lie along the locus J − H = 0.6 + 0.5 × (H − K) What is the star’s intrinsic colour? The relationships between stellar mass, H band luminosity and H-K colour for low mass main sequence stars are given by: ...
... The intrinsic colours of main sequence stars lie along the locus J − H = 0.6 + 0.5 × (H − K) What is the star’s intrinsic colour? The relationships between stellar mass, H band luminosity and H-K colour for low mass main sequence stars are given by: ...
Chandra - Astronomy at Swarthmore College
... (Florida Institute of Technology), Marc Gagné (West Chester), Asif ud-Doula (Penn St. Worthington-Scranton) with Emma Wollman (Caltech, Swarthmore ’09), James MacArthur (Stanford, Swarthmore ’11), Zack Li (Swarthmore ’16) ...
... (Florida Institute of Technology), Marc Gagné (West Chester), Asif ud-Doula (Penn St. Worthington-Scranton) with Emma Wollman (Caltech, Swarthmore ’09), James MacArthur (Stanford, Swarthmore ’11), Zack Li (Swarthmore ’16) ...
A Tale of Two (Solar) Telescopes: something old, something
... B, 2 MK, for broad 0.06-6 keV band. Now XMM has moved closer to Chandra, less challenging to our expectations for stellar cycles. In hindsight, extreme darkening of Alpha Cen seen by XMM in 0.2-2 keV band has precedence on Sun, but was not so obvious in stars during ROSAT era owing to poor energy di ...
... B, 2 MK, for broad 0.06-6 keV band. Now XMM has moved closer to Chandra, less challenging to our expectations for stellar cycles. In hindsight, extreme darkening of Alpha Cen seen by XMM in 0.2-2 keV band has precedence on Sun, but was not so obvious in stars during ROSAT era owing to poor energy di ...
The X-ray Bursters Problem and its Implications to the Equation of
... thermonuclear instabilities on accretion stars that produce thermonuclear (TypeI) X-ray bursts. These bursts are caused by unstable burning in the outer layers of the neutron star due to accreted material from a companion in a close binary system. When these objects are bright enough, the local X-ra ...
... thermonuclear instabilities on accretion stars that produce thermonuclear (TypeI) X-ray bursts. These bursts are caused by unstable burning in the outer layers of the neutron star due to accreted material from a companion in a close binary system. When these objects are bright enough, the local X-ra ...
Document
... Almost identical morphology from the radio to X-ray band: the optical, UV and X-ray data (and spectral indices) are consistent with synchrotron emission ...
... Almost identical morphology from the radio to X-ray band: the optical, UV and X-ray data (and spectral indices) are consistent with synchrotron emission ...
1.3 Accretion power in astrophysics
... It is the steady loss of mass from the surface of a star into interstellar space The Sun has a wind (the “solar wind”) but the winds of hot stars can be a billion times as strong as the Sun’s ...
... It is the steady loss of mass from the surface of a star into interstellar space The Sun has a wind (the “solar wind”) but the winds of hot stars can be a billion times as strong as the Sun’s ...
The “Tuning Fork” Diagram Galaxy Properties 1 “Early”
... • Applied to nuclei of spirals Î presence of massive black holes • Also often applied to ...
... • Applied to nuclei of spirals Î presence of massive black holes • Also often applied to ...
Cole Miller: Challenges in the measurements of neutron star radii
... NS masses are known up to 2 Msun. What about radii? • Radii from X-ray bursts • Radii from cooling neutron stars • Radii from X-ray light curves • The promise of gravitational waves ...
... NS masses are known up to 2 Msun. What about radii? • Radii from X-ray bursts • Radii from cooling neutron stars • Radii from X-ray light curves • The promise of gravitational waves ...
Lecture 12: Age, Metalicity, and Observations Abundance
... • Main events in the evolution of the Universe: – The Big Bang (inflation of a bubble of false vacuum) – Symmetry breaking à matter/anti-matter ratio – Quark + antiquark annihilation à photon/baryon ratio – The quark soup à heavy quark decay – Quark-Hadron phase transition and neutron decay ...
... • Main events in the evolution of the Universe: – The Big Bang (inflation of a bubble of false vacuum) – Symmetry breaking à matter/anti-matter ratio – Quark + antiquark annihilation à photon/baryon ratio – The quark soup à heavy quark decay – Quark-Hadron phase transition and neutron decay ...
Document
... Absence of surface Here we mostly discuss close binaries with accretion • Lack of pulsations • No burster-like bursts Nowhere to collect matter. (however, see below about some alternatives) • Low accretion efficiency (also for Sgr A*) ADAF. Energy is taken under horizon. • No boundary layer (Sunyae ...
... Absence of surface Here we mostly discuss close binaries with accretion • Lack of pulsations • No burster-like bursts Nowhere to collect matter. (however, see below about some alternatives) • Low accretion efficiency (also for Sgr A*) ADAF. Energy is taken under horizon. • No boundary layer (Sunyae ...
ppt - IASF Milano
... •There are very few constraints on groups scale (1013 ≤ M ≤ 1014 Msun) , where numerical predictions are more accurate because a large number of halo can be simulated. ...
... •There are very few constraints on groups scale (1013 ≤ M ≤ 1014 Msun) , where numerical predictions are more accurate because a large number of halo can be simulated. ...
Neutron Stars and Black Holes
... Since the Schwarzschild radius of a black hole is rSch = 2 GM / c2, the radius of a black hole is proportional to its mass. A one billion solar mass black hole will have a radius of 3 X 109 km. Since one Astronomical Unit ~ 1.5 X 108 km, it follows that a one billion solar mass black hole has a rad ...
... Since the Schwarzschild radius of a black hole is rSch = 2 GM / c2, the radius of a black hole is proportional to its mass. A one billion solar mass black hole will have a radius of 3 X 109 km. Since one Astronomical Unit ~ 1.5 X 108 km, it follows that a one billion solar mass black hole has a rad ...
Investigating Supernova Remnants - Chandra X
... several months to more than a year. The material ejected by the star forms a planetary nebula which expands into the surrounding interstellar medium at ~17to35 km/s. The core of the star left in the center of the planetary nebula is called a white dwarf. The planetary nebula is very tenuous, and bec ...
... several months to more than a year. The material ejected by the star forms a planetary nebula which expands into the surrounding interstellar medium at ~17to35 km/s. The core of the star left in the center of the planetary nebula is called a white dwarf. The planetary nebula is very tenuous, and bec ...
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.