Document
... We have developed a physically meaningful line-profile model, yet one that is simple and not tied to any one proposed mechanism of hot-star X-ray production. Described in Owocki & Cohen (2001, ApJ, 559, 1108), the model assumes a smoothly and spherically symmetrically distributed accelerating X-ray ...
... We have developed a physically meaningful line-profile model, yet one that is simple and not tied to any one proposed mechanism of hot-star X-ray production. Described in Owocki & Cohen (2001, ApJ, 559, 1108), the model assumes a smoothly and spherically symmetrically distributed accelerating X-ray ...
Astronomy Learning Objectives and Study Questions for Chapter 13
... 3. Explain why the Sun will or will not ever become a nova. 4. Describe what spectral observation distinguishes a Type Ia from a Type II supernova, and briefly explain why the spectra of these objects are different. 5. Draw a neat, well labeled sketch of a rotating neutron star and explain how this ...
... 3. Explain why the Sun will or will not ever become a nova. 4. Describe what spectral observation distinguishes a Type Ia from a Type II supernova, and briefly explain why the spectra of these objects are different. 5. Draw a neat, well labeled sketch of a rotating neutron star and explain how this ...
Deep O/IR Survey Of Chandra Galactic Bulge Fields
... analysis suggest that a large subset of the sources are intrinsically hard, and reasonably described by a power law with photon index =0. The typical luminosities of these objects are in the range 10 3133 erg/s. The largest well studied class of objects fitting this description are high magnetic fie ...
... analysis suggest that a large subset of the sources are intrinsically hard, and reasonably described by a power law with photon index =0. The typical luminosities of these objects are in the range 10 3133 erg/s. The largest well studied class of objects fitting this description are high magnetic fie ...
Bez tytułu slajdu
... The neutron ball is similar to a giant atomic nucleus with Z=1057. With such a big compression, neutrons start to "crowd-up", following the Pauli's rule, which does not allow them to be in the same quantum state. It is energetically useful to replace some neutrons with protons, or even by isolated q ...
... The neutron ball is similar to a giant atomic nucleus with Z=1057. With such a big compression, neutrons start to "crowd-up", following the Pauli's rule, which does not allow them to be in the same quantum state. It is energetically useful to replace some neutrons with protons, or even by isolated q ...
Draft A101 Slide Set #1 - Astronomical Society of the Pacific
... The chart illustrates the relative masses of superdense cosmic objects, from white dwarf stars to supermassive black holes inhabiting the cores of most galaxies. Credit: NASA/JPLCaltech/SAO. ...
... The chart illustrates the relative masses of superdense cosmic objects, from white dwarf stars to supermassive black holes inhabiting the cores of most galaxies. Credit: NASA/JPLCaltech/SAO. ...
X-rays - Astronomy at Swarthmore College
... Chandra observations of massive stars, indicating that a surprising variety of high-energy physical processes are occurring in this class of stars. •Normal massive stars with strong radiation-driven winds have x-ray emitting plasma distributed throughout their winds: Standard wind-shock models expla ...
... Chandra observations of massive stars, indicating that a surprising variety of high-energy physical processes are occurring in this class of stars. •Normal massive stars with strong radiation-driven winds have x-ray emitting plasma distributed throughout their winds: Standard wind-shock models expla ...
ppt - SLAC
... hydrogen envelopes, leaving their helium cores exposed, often in a binary system, and that are doomed, within a few million years, to explode as Type Ib or Ic supernovae. There are two spectral subclasses of Wolf-Rayets: type WN, which have prominent emission lines of helium and nitrogen, and type W ...
... hydrogen envelopes, leaving their helium cores exposed, often in a binary system, and that are doomed, within a few million years, to explode as Type Ib or Ic supernovae. There are two spectral subclasses of Wolf-Rayets: type WN, which have prominent emission lines of helium and nitrogen, and type W ...
X-ray studies of star and planet formation Eric Feigelson
... 6. Discovering the fate of OB stellar winds OB winds are radiatively acceleration near the stellar surface where they are studied with UV and X-ray emission lines. But the fate of the winds on parsec scales was unknown … predicted to produce strong X-rays in shock against molecular cloud (Weaver/Mc ...
... 6. Discovering the fate of OB stellar winds OB winds are radiatively acceleration near the stellar surface where they are studied with UV and X-ray emission lines. But the fate of the winds on parsec scales was unknown … predicted to produce strong X-rays in shock against molecular cloud (Weaver/Mc ...
Tom Maccarone (Texas Tech University)
... Can do fundamental physics with these objects, but they are also important probes of globular cluster dynamics We are starting to see the first Milky Way globular cluster black ...
... Can do fundamental physics with these objects, but they are also important probes of globular cluster dynamics We are starting to see the first Milky Way globular cluster black ...
Summary - Chandra X
... -Fast outflow in GRO J1655-40 does indeed appear to be magnetically driven by process of elimination. Still, a low density slow thermal wind caused by irradiation heating should produce a mass loss rate 7 times higher than the accretion rate! New simulations of large (~10 pc) scale radiation-driven ...
... -Fast outflow in GRO J1655-40 does indeed appear to be magnetically driven by process of elimination. Still, a low density slow thermal wind caused by irradiation heating should produce a mass loss rate 7 times higher than the accretion rate! New simulations of large (~10 pc) scale radiation-driven ...
Equation of state constraints for the cold dense matter inside neutron
... Kazan Federal University, 420008, Kremlevskaya 18, Kazan, Russia ...
... Kazan Federal University, 420008, Kremlevskaya 18, Kazan, Russia ...
Shocking Truth about Massive Stars Lidia Oskinova Chandra’s First Decade of Discovery
... ’’A very energetic explosion of a massive star is likely to create a ... fireball.... the inner core of a massive, rapidly rotating star collapses into a ~10 M Kerr black hole ... A superstrong ~10 15 G magnetic field is needed to make the object ... a microquasar. Such events must be vary rare...to ...
... ’’A very energetic explosion of a massive star is likely to create a ... fireball.... the inner core of a massive, rapidly rotating star collapses into a ~10 M Kerr black hole ... A superstrong ~10 15 G magnetic field is needed to make the object ... a microquasar. Such events must be vary rare...to ...
X-ray Astronomy and the search for Black Holes
... • Above about E~2 keV, there is a highly absorbed, hard component. – There is a clear detection of Fe K complex, indicating thin thermal origin – A single kT (~5 keV) fit would work – But the effective bandpass was narrow (E~2-10 keV) so only weak constraints can be placed on models – Reminescent of ...
... • Above about E~2 keV, there is a highly absorbed, hard component. – There is a clear detection of Fe K complex, indicating thin thermal origin – A single kT (~5 keV) fit would work – But the effective bandpass was narrow (E~2-10 keV) so only weak constraints can be placed on models – Reminescent of ...
An Archive of Chandra Observations of Regions of Star Formation...
... The archive is designed to aid both the X-ray astronomer with a desire to compare X-ray datasets and the star formation astronomer wishing to compare stars across the spectrum. It brings together Chandra data on open clusters and other bright, variable, young stars for the study of the various physi ...
... The archive is designed to aid both the X-ray astronomer with a desire to compare X-ray datasets and the star formation astronomer wishing to compare stars across the spectrum. It brings together Chandra data on open clusters and other bright, variable, young stars for the study of the various physi ...
Part B
... Attenuation of light by dust and gas in the interstellar medium, and by the Earth’s atmosphere. Only the visual, infrared, and radio regions of the electromagnetic spectrum are directly observable from the Earth’s surface. ...
... Attenuation of light by dust and gas in the interstellar medium, and by the Earth’s atmosphere. Only the visual, infrared, and radio regions of the electromagnetic spectrum are directly observable from the Earth’s surface. ...
The Sun`s X- ray Emission During the Recent Solar
... the gray areas indicated. Active regions associated with X-ray flux increases are shown (e.g., sunspot regions 11016 and 11017) as identified by the U.S. National Oceanic and Atmospheric Administration. ...
... the gray areas indicated. Active regions associated with X-ray flux increases are shown (e.g., sunspot regions 11016 and 11017) as identified by the U.S. National Oceanic and Atmospheric Administration. ...
PowerPoint - Astronomy at Swarthmore College
... rotator, 1 Ori C (O6 V), corresponding to four different viewing angles with respect to the magnetic axis, are used to constrain the temperature, spatial location, and kinematics of the hot plasma on this very young hot star with a strong (1100 G) dipole field. The plasma is moving, but only at spe ...
... rotator, 1 Ori C (O6 V), corresponding to four different viewing angles with respect to the magnetic axis, are used to constrain the temperature, spatial location, and kinematics of the hot plasma on this very young hot star with a strong (1100 G) dipole field. The plasma is moving, but only at spe ...
Gravitationally redshifted absorption lines in the x
... Correlation between the blackbody temperatures and count rates of all bursts detected with EPIC-pn. ...
... Correlation between the blackbody temperatures and count rates of all bursts detected with EPIC-pn. ...
AMNH_colloquium_2May07_v7b
... O star X-ray emission line profiles are broadened, shifted, and asymmetric as the wind-shock scenario predicts But the degree of asymmetry requires significantly lower wind optical depths than are expected in these stars Clumping and the associated porosity can, in principle, alleviate this problem, ...
... O star X-ray emission line profiles are broadened, shifted, and asymmetric as the wind-shock scenario predicts But the degree of asymmetry requires significantly lower wind optical depths than are expected in these stars Clumping and the associated porosity can, in principle, alleviate this problem, ...
PG_Lecture_Dec18_2008
... in the convective zone of its interior. Heating may occur by either dissipation of MHD waves or numerous tiny flares. The magnetic field continually re-created by an α-ω dynamo action in the stellar interior – differential rotation (ω) + convection (α). ...
... in the convective zone of its interior. Heating may occur by either dissipation of MHD waves or numerous tiny flares. The magnetic field continually re-created by an α-ω dynamo action in the stellar interior – differential rotation (ω) + convection (α). ...
A Decade in the Life of the Massive Black-Hole Binary... Silas Laycock !
... • At each trial period we computed the mean count-rate in the phase range 0.4-0.6, which is mid-eclipse. • Chandra and XMM-Newton data were analyzed separately, yielding two sets of flux-minima, most of which are mutually exclusive. • The resulting best period, also found by the Lomb-Scargle peri ...
... • At each trial period we computed the mean count-rate in the phase range 0.4-0.6, which is mid-eclipse. • Chandra and XMM-Newton data were analyzed separately, yielding two sets of flux-minima, most of which are mutually exclusive. • The resulting best period, also found by the Lomb-Scargle peri ...
Astronomy Astrophysics + Infrared identification of 2XMM J191043.4
... of the northern hemisphere to a depth of K = 18 mag, with additional data from two deeper, small-area high-redshift galaxy surveys. Using the Wide Field Camera (WFCAM) on the United Kingdom Infrared Telescope (UKIRT), the survey achieved a pixel resolution of 0.14 by use of the micro-stepping tech ...
... of the northern hemisphere to a depth of K = 18 mag, with additional data from two deeper, small-area high-redshift galaxy surveys. Using the Wide Field Camera (WFCAM) on the United Kingdom Infrared Telescope (UKIRT), the survey achieved a pixel resolution of 0.14 by use of the micro-stepping tech ...
A Proposed Collaboration Between LIGO
... More of these hints would be very helpful. For the first time in history a Harvard group has observed X-ray transients in coincidence with optical CCSNe. This discovery has proven that even if a supernova had its light absorbed with dust, X-ray transients that are more penetrating, and thus could be ...
... More of these hints would be very helpful. For the first time in history a Harvard group has observed X-ray transients in coincidence with optical CCSNe. This discovery has proven that even if a supernova had its light absorbed with dust, X-ray transients that are more penetrating, and thus could be ...
Program_files/40 Years of Microquasarsembed
... X-Ray Binaries • ~300 X-ray emitting binary stars (XRBS) found in our own Milky Way galaxy, detected by X-ray satellites at ~1-10 kev (van Paradis 1995, Liu et al. 2000, 2001 catalogues) • High Mass ~ 10 Msun • Low Mass ~ 1 Msun • .All powered by accretion onto a compact object (neutron star or bla ...
... X-Ray Binaries • ~300 X-ray emitting binary stars (XRBS) found in our own Milky Way galaxy, detected by X-ray satellites at ~1-10 kev (van Paradis 1995, Liu et al. 2000, 2001 catalogues) • High Mass ~ 10 Msun • Low Mass ~ 1 Msun • .All powered by accretion onto a compact object (neutron star or bla ...
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.