Presentation - Harvard-Smithsonian Center for Astrophysics
... plus UV wavelengths define 1D energy levels in Mg VII ...
... plus UV wavelengths define 1D energy levels in Mg VII ...
Chapter22_New
... I like to use the subject of the size and shape of the galaxy as an example of the way that science often proceeds by fits and starts with some wrong turns. I treat the work of Herschel and Kapteyn, though basically wrong, with respect. 3. The Rotation of the Milky Way Rotation curves for other gala ...
... I like to use the subject of the size and shape of the galaxy as an example of the way that science often proceeds by fits and starts with some wrong turns. I treat the work of Herschel and Kapteyn, though basically wrong, with respect. 3. The Rotation of the Milky Way Rotation curves for other gala ...
R and FUV Observations of Star Formation in
... 4-6 Gyr since last major cluster merger, so there may not have been enough time for a steady state to be set up (cooling leads to cold gas leads to star formation). ...
... 4-6 Gyr since last major cluster merger, so there may not have been enough time for a steady state to be set up (cooling leads to cold gas leads to star formation). ...
3011800000631
... AXP 4U 0142+61 is 7 × 108 cm. The disk inner radius is close to the corotation radius but somewhat larger. The star is a weak propeller, accreting while spinning down. Taking the unlikely extreme value of AV = 2.6 leads to B = 4 × 1013 G (on the poles). We infer the value of the inner radius of the ...
... AXP 4U 0142+61 is 7 × 108 cm. The disk inner radius is close to the corotation radius but somewhat larger. The star is a weak propeller, accreting while spinning down. Taking the unlikely extreme value of AV = 2.6 leads to B = 4 × 1013 G (on the poles). We infer the value of the inner radius of the ...
ASTRONOMY 0089: EXAM 2 Class Meets M,W,F, 1:00 PM Mar 22
... 20. To which region of the Sun does the following refer? It is an inhomogeneous and tenuous region with a temperature of more than 106 K (1 millionK). At visible wavelengths it is best studied during a Solar eclipse. a. the chromosphere. b. the core c. the photosphere d. the convective zone. e. the ...
... 20. To which region of the Sun does the following refer? It is an inhomogeneous and tenuous region with a temperature of more than 106 K (1 millionK). At visible wavelengths it is best studied during a Solar eclipse. a. the chromosphere. b. the core c. the photosphere d. the convective zone. e. the ...
Stellar Evolution II
... intended to promote, recognize, and reward exemplary performance among graduate teaching assistants assigned to PTYS undergraduate courses. The award consists of an expense-paid trip to a domestic (continental U.S.) professional meeting chosen by the recipient, who must separately negotiate terms of ...
... intended to promote, recognize, and reward exemplary performance among graduate teaching assistants assigned to PTYS undergraduate courses. The award consists of an expense-paid trip to a domestic (continental U.S.) professional meeting chosen by the recipient, who must separately negotiate terms of ...
An X-ray and Radio Study of the Varying Expansion Velocities in
... and southwestern sides of the remnant are about a factor of two higher than those in the east and northeast. We showed in an earlier work that this is related to an offset of the explosion site from the geometric center of the remnant due to a density gradient in the ISM, and using our refined measu ...
... and southwestern sides of the remnant are about a factor of two higher than those in the east and northeast. We showed in an earlier work that this is related to an offset of the explosion site from the geometric center of the remnant due to a density gradient in the ISM, and using our refined measu ...
Forman - Chandra X
... Red ellipticals - for an assumed =1.9 power law nH ~ 0.7-1.1 x 10 22 cm-2 (90% confidence) • Some “types” absorbed, some not absorbed ...
... Red ellipticals - for an assumed =1.9 power law nH ~ 0.7-1.1 x 10 22 cm-2 (90% confidence) • Some “types” absorbed, some not absorbed ...
Document
... that there is a black hole that came from a massive star: – Strong X-ray sources (usually flares). – Optically dark objects (that is, only one star is seen in the spectrum, and it is the mass-losing one). – Masses too large to be a white dwarf or a neutron star. ...
... that there is a black hole that came from a massive star: – Strong X-ray sources (usually flares). – Optically dark objects (that is, only one star is seen in the spectrum, and it is the mass-losing one). – Masses too large to be a white dwarf or a neutron star. ...
Chapter 15 Observational Evidence for Black Holes
... 2. In 1972, a radio source was found in the same general area and identified optically with a blue supergiant star called HDE226868. Correlations in radio activity of HDE226868 and X-ray activity of Cygnus X-1 implied that the two were probably components of the same binary system. 3. Doppler measur ...
... 2. In 1972, a radio source was found in the same general area and identified optically with a blue supergiant star called HDE226868. Correlations in radio activity of HDE226868 and X-ray activity of Cygnus X-1 implied that the two were probably components of the same binary system. 3. Doppler measur ...
Wednesday, April 23 - Otterbein University
... • Implosion of a white dwarf after it accretes a certain amount of matter, reaching about ...
... • Implosion of a white dwarf after it accretes a certain amount of matter, reaching about ...
AGN Workshop
... • TESTS: HST studies of hosts (morphology); Better info on environments; evolution with redshift; Primus; imaging around SDSS binaries? ...
... • TESTS: HST studies of hosts (morphology); Better info on environments; evolution with redshift; Primus; imaging around SDSS binaries? ...
samba2002v2
... Theoretical models, in high energy astrophysics, suggest that non thermal emission mechanisms, scattering of radiation through highly asymmetric systems or vacuum polarization and birefringence in intense magnetic field can produce a high degree of linear polarization of X-ray radiation [1,2,3,4]. E ...
... Theoretical models, in high energy astrophysics, suggest that non thermal emission mechanisms, scattering of radiation through highly asymmetric systems or vacuum polarization and birefringence in intense magnetic field can produce a high degree of linear polarization of X-ray radiation [1,2,3,4]. E ...
Stars, Galaxies, and the Universe
... What is a parallax? How is it useful in astronomy? Parallax is the apparent change in an object’s position when viewed from two different places. Astronomers can use parallax to calculate distances to nearby stars. List three characteristics used to classify stars. Size, temperature (or color) and ...
... What is a parallax? How is it useful in astronomy? Parallax is the apparent change in an object’s position when viewed from two different places. Astronomers can use parallax to calculate distances to nearby stars. List three characteristics used to classify stars. Size, temperature (or color) and ...
PHY418 Particle Astrophysics
... • But it’s quite hard to work out how they do it • magnetic geometry at the termination shock must be quasiperpendicular, which disfavours diffusive shock acceleration • but maybe enough small-scale turbulence is generated at the shock • the expected electron power law of E−2.2 is right for the Crab ...
... • But it’s quite hard to work out how they do it • magnetic geometry at the termination shock must be quasiperpendicular, which disfavours diffusive shock acceleration • but maybe enough small-scale turbulence is generated at the shock • the expected electron power law of E−2.2 is right for the Crab ...
Galaxy Evolution
... as a function of M500 (bottom axis) and velocity dispersion (top axis). X-ray gas mass fractions from Vikhlinin et al. (2006; circles) and Gastaldello et al. (2006; triangles) and the stellar mass fractions ( BCG +ICL+galaxies; squares) for systems in our sample with masses that overlap the range sh ...
... as a function of M500 (bottom axis) and velocity dispersion (top axis). X-ray gas mass fractions from Vikhlinin et al. (2006; circles) and Gastaldello et al. (2006; triangles) and the stellar mass fractions ( BCG +ICL+galaxies; squares) for systems in our sample with masses that overlap the range sh ...
The spin and orbit of the newly discovered pulsar IGR J17480-2446
... Although no residual modulation at the orbital period is observed, the phases of the first harmonic are strongly affected by timing noise. The reduced χ2 we obtain modelling their evolution with Eq. (2) is extremely large (11.9 over 662 d.o.f.). Such a behaviour is most probably caused by to pulse s ...
... Although no residual modulation at the orbital period is observed, the phases of the first harmonic are strongly affected by timing noise. The reduced χ2 we obtain modelling their evolution with Eq. (2) is extremely large (11.9 over 662 d.o.f.). Such a behaviour is most probably caused by to pulse s ...
Semiar PPT
... of a massive star (at least in several cases!). 2. The short GRBs have much less energy and are associated with old stellar population. ...
... of a massive star (at least in several cases!). 2. The short GRBs have much less energy and are associated with old stellar population. ...
motl_bsu_021210
... horizon*, to escape from the event horizon you must have a velocity equal to the speed of light (impossible for any material body). The region inside the event horizon is fundamentally isolated (causally disconnected) from the outside Universe From a certain point of view, astrophysical black holes ...
... horizon*, to escape from the event horizon you must have a velocity equal to the speed of light (impossible for any material body). The region inside the event horizon is fundamentally isolated (causally disconnected) from the outside Universe From a certain point of view, astrophysical black holes ...
BML_V
... of star formation, as well as from sundry other denizens of the Galactic zoo (O-B stars, µquasars, the central black hole, Galactic γ & X-ray sources, etc). Our Galaxy is much the best laboratory for these explorations, as it is close, allows better angular resolution, and potentially allows for the ...
... of star formation, as well as from sundry other denizens of the Galactic zoo (O-B stars, µquasars, the central black hole, Galactic γ & X-ray sources, etc). Our Galaxy is much the best laboratory for these explorations, as it is close, allows better angular resolution, and potentially allows for the ...
RachelStarProject
... A red giant is a very big star that weighs about one half to ten times as much as our sun. They are called red giants because they look red and are very big. Many red giants could fit thousands and thousands of suns, like the one in our solar system, inside them! ...
... A red giant is a very big star that weighs about one half to ten times as much as our sun. They are called red giants because they look red and are very big. Many red giants could fit thousands and thousands of suns, like the one in our solar system, inside them! ...
Millisecond Pulsars in X-Ray Binaries - CIERA
... is about 6 percent, while the upper limit on the pulsed amplitude for most NS/LMXBs is 1 per cent or less, raising the question of what is different about this group of 5 pulsars: why is it so difficult to find persistent millisecond pulsations in most NS/LMXBs? It should be noted that none of the m ...
... is about 6 percent, while the upper limit on the pulsed amplitude for most NS/LMXBs is 1 per cent or less, raising the question of what is different about this group of 5 pulsars: why is it so difficult to find persistent millisecond pulsations in most NS/LMXBs? It should be noted that none of the m ...
white dwarf supernova
... B) The white dwarf C) They are generally the same temperature D) Can’t answer without more information Which is more luminous, a red giant star or a white dwarf? ...
... B) The white dwarf C) They are generally the same temperature D) Can’t answer without more information Which is more luminous, a red giant star or a white dwarf? ...
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.