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 ...
What happens close to a black hole?
... • Multi-wavelength studies (UV to X-rays) spectra, variability. • Periodic and aperiodic variability. • Broad band X-ray spectroscopy non-thermal components, cyclotron lines. • Surveys All-sky, Galactic plane, deep. ...
... • Multi-wavelength studies (UV to X-rays) spectra, variability. • Periodic and aperiodic variability. • Broad band X-ray spectroscopy non-thermal components, cyclotron lines. • Surveys All-sky, Galactic plane, deep. ...
Document
... 1999: using ASCA, X-1 in M82 was found to vary by up to a factor of four, confirming that this bright source was indeed a single object. *Over half of ULXs are known to be variable, ruling out the multiple source or SNR hypothesis. ...
... 1999: using ASCA, X-1 in M82 was found to vary by up to a factor of four, confirming that this bright source was indeed a single object. *Over half of ULXs are known to be variable, ruling out the multiple source or SNR hypothesis. ...
$doc.title
... have duty y les of order 2% or less - the low quies ent ux of the neutron star transient KS 1730260 indi ates that its mean a retion rate must be about two orders of magnitude lower than its mean luminosity in outburst or its rust would show more eviden e of strong heating (Rutledge et al. 2002 ...
... have duty y les of order 2% or less - the low quies ent ux of the neutron star transient KS 1730260 indi ates that its mean a retion rate must be about two orders of magnitude lower than its mean luminosity in outburst or its rust would show more eviden e of strong heating (Rutledge et al. 2002 ...
Slides from Dr. Frank`s Lecture17
... Interacting Binary Stars Why some binaries interact and others don’t? The following processes are inevitable in a binary: 1) The binary separation decreases because of gravitational radiation and other angular momentum losses. 2) The component stars will evolve and change size (for example becomin ...
... Interacting Binary Stars Why some binaries interact and others don’t? The following processes are inevitable in a binary: 1) The binary separation decreases because of gravitational radiation and other angular momentum losses. 2) The component stars will evolve and change size (for example becomin ...
The Birth of a Supernova Seen in Real Time
... velocities inferred for GRBs and XRFs. The radio emission thus points to an ordinary core-collapse supernova in which only a tiny fraction of the explosion energy is coupled to fast ejecta. Of course, the ultimate clincher in constraining the expansion speed of the ejecta is through direct measureme ...
... velocities inferred for GRBs and XRFs. The radio emission thus points to an ordinary core-collapse supernova in which only a tiny fraction of the explosion energy is coupled to fast ejecta. Of course, the ultimate clincher in constraining the expansion speed of the ejecta is through direct measureme ...
Can we determine the grain composition of the Interstellar Medium with
... empirical XAFS data taken at synchrotron beamlines to determine exact chemical state of the astrophysical dust Recent measurements of soft X-ray XAFS at ALS (Sept 04) FUTURE MISSIONS : area + spectral resolution ...
... empirical XAFS data taken at synchrotron beamlines to determine exact chemical state of the astrophysical dust Recent measurements of soft X-ray XAFS at ALS (Sept 04) FUTURE MISSIONS : area + spectral resolution ...
Paper (pdf)
... Astronomical observations at all wavelengths have revealed the existence of numerous types of objects where extremely energetic and exotic phenomena occur. These include X-ray binaries and active galactic nuclei (AGN) among others, where accretion onto a compact object (collapsed star or massive bla ...
... Astronomical observations at all wavelengths have revealed the existence of numerous types of objects where extremely energetic and exotic phenomena occur. These include X-ray binaries and active galactic nuclei (AGN) among others, where accretion onto a compact object (collapsed star or massive bla ...
Document
... The strong lines in the Chandra spectrum of z Puppis can be fit by reasonable combinations of wind parameters. These fits indicate that the X-ray emitting plasma surrounding this star is embedded in the accelerating and absorbing wind. ...
... The strong lines in the Chandra spectrum of z Puppis can be fit by reasonable combinations of wind parameters. These fits indicate that the X-ray emitting plasma surrounding this star is embedded in the accelerating and absorbing wind. ...
HE and VHE emission from X-ray binaries
... Since these sources are located in the Galactic plane, a sensitivity better by a factor X with respect to current instruments means detecting ~3X sources. • Binaries with short orbital periods, difficult for Be but likely for O donors, should be ‘on’ all the time, although strong variability due to ...
... Since these sources are located in the Galactic plane, a sensitivity better by a factor X with respect to current instruments means detecting ~3X sources. • Binaries with short orbital periods, difficult for Be but likely for O donors, should be ‘on’ all the time, although strong variability due to ...
Pallavicini - IASF Milano
... GO programmes, are starting to cover the full age-metallicity plane of nearby open clusters. They allow addressing the question whether a cluster of a given age is representative of all clusters with the same age. ...
... GO programmes, are starting to cover the full age-metallicity plane of nearby open clusters. They allow addressing the question whether a cluster of a given age is representative of all clusters with the same age. ...
this paper
... line (0.525 keV).7 A five-way chamber was added to house the polarized source multilayer (ML) mirror. The mirror and a twin were provided by Reflective X-ray Optics (RXO), with a coating consisting of 200 layers of 5.04Å of W alternating with 11.76 Å of B4 C. The wavelength, λ, of the Bragg peak f ...
... line (0.525 keV).7 A five-way chamber was added to house the polarized source multilayer (ML) mirror. The mirror and a twin were provided by Reflective X-ray Optics (RXO), with a coating consisting of 200 layers of 5.04Å of W alternating with 11.76 Å of B4 C. The wavelength, λ, of the Bragg peak f ...
Who’s Afraid of a Stellar Superflare? Rachel Osten GSFC
... galactic GRB with fluence 100kJ m-2 could deplete the ozone layer on Earth globally to 38%: Late Ordovician mass extinction caused by GRB? ...
... galactic GRB with fluence 100kJ m-2 could deplete the ozone layer on Earth globally to 38%: Late Ordovician mass extinction caused by GRB? ...
JOINT DISCUSSION mirror which reflects the light of the primary
... Three balloon flights were carried out last summer, all three at an altitude of 80,000 ft (25 km, air pressure 4 % of ground pressure). The first of these flights had the purpose only of testing the pointing mechanism, but in the second and third flight the full telescope was flown. Eight thousand p ...
... Three balloon flights were carried out last summer, all three at an altitude of 80,000 ft (25 km, air pressure 4 % of ground pressure). The first of these flights had the purpose only of testing the pointing mechanism, but in the second and third flight the full telescope was flown. Eight thousand p ...
HEA_Accretion_2003_04
... For neutron star with a strong magnetic field, disk is disrupted in inner parts. Material is ...
... For neutron star with a strong magnetic field, disk is disrupted in inner parts. Material is ...
Accretion
... • Magnetic loops rise out of the plane of the disk at any angle – the global field geometry is “tangled” • The field lines confine and carry plasma across the disk • Reconnection and snapping of the loops releases energy into the disk atmosphere – mostly in X-rays • The magnetic field also transfers ...
... • Magnetic loops rise out of the plane of the disk at any angle – the global field geometry is “tangled” • The field lines confine and carry plasma across the disk • Reconnection and snapping of the loops releases energy into the disk atmosphere – mostly in X-rays • The magnetic field also transfers ...
Paper 3 (pdf)
... unobserved effects of quantum electrodynamics (QED) are predicted to have a profound effect on the X-ray spectra and polarization that can be tested with soft X-ray polarimetry. Measuring the polarization of the radiation from magnetars in the X-ray band will not only verify the strength of their ma ...
... unobserved effects of quantum electrodynamics (QED) are predicted to have a profound effect on the X-ray spectra and polarization that can be tested with soft X-ray polarimetry. Measuring the polarization of the radiation from magnetars in the X-ray band will not only verify the strength of their ma ...
The Chandra Orion Ultradeep Project Eric Feigelson
... Some (but not all) flare loops are longer than seen in other stars, perhaps extending to the disk ...
... Some (but not all) flare loops are longer than seen in other stars, perhaps extending to the disk ...
7 November 2012 X-ray Astrophysics
... so radiate most strongly in the visible waveband. But not all stars are the same temperature or colour: whilst blue stars are at 15,000-80,000 K, yellower stars like our Sun are at 5,000-8000 K and the coolest, reddest stars have temperatures of 2,000-4000K. Of course, many young massive stars are s ...
... so radiate most strongly in the visible waveband. But not all stars are the same temperature or colour: whilst blue stars are at 15,000-80,000 K, yellower stars like our Sun are at 5,000-8000 K and the coolest, reddest stars have temperatures of 2,000-4000K. Of course, many young massive stars are s ...
Fitting X-ray Spectra with Imperfect Models
... Sample of young star spectra from the Chandra HETG ...
... Sample of young star spectra from the Chandra HETG ...
Low-Res Version - Chandra X
... as radio, infra-red, ultra-violet and gamma, cannot be seen with the human eye, and thus do not have any "color". To see the invisible wavelengths, we need detectors that are especially designed to see those other wavelengths, such as the instruments on Chandra. Sometimes images taken by telescopes ...
... as radio, infra-red, ultra-violet and gamma, cannot be seen with the human eye, and thus do not have any "color". To see the invisible wavelengths, we need detectors that are especially designed to see those other wavelengths, such as the instruments on Chandra. Sometimes images taken by telescopes ...
Deep $ I $-band imaging of $ z=\ mathsf {5.99} $ quasar
... extended X-ray source is statistically significant. It is comprised of 7 counts, which exceeds by far the expected background flux of 0.13 counts. He estimated that the probability of observing 7 photons in a 10 arcsec2 box is 5.8×10−9. What are the chances of observing a galaxy with the given magni ...
... extended X-ray source is statistically significant. It is comprised of 7 counts, which exceeds by far the expected background flux of 0.13 counts. He estimated that the probability of observing 7 photons in a 10 arcsec2 box is 5.8×10−9. What are the chances of observing a galaxy with the given magni ...
ppt 2.6 - NRAO: Socorro, New Mexico
... Studies of CW emission provide unique information about the densities, temperature ranges and structure of the interaction region Detailed timing, spectral and imaging studies suggest shocks and winds are not smooth and homogeneous shape, stability and aberration of the shock cone important X-ray li ...
... Studies of CW emission provide unique information about the densities, temperature ranges and structure of the interaction region Detailed timing, spectral and imaging studies suggest shocks and winds are not smooth and homogeneous shape, stability and aberration of the shock cone important X-ray li ...
PowerPoint - Astronomy at Swarthmore College
... and Mg XI (solid histograms) . Show are the resonant (left), intercombination (middle) and forbidden (right) lines. In hot stars, the forbidden-line strength of He-like ions is reduced by photoexcitation of electrons in the 3S1 state by photospheric UV radiation. We do not detect the Mg XI f line. T ...
... and Mg XI (solid histograms) . Show are the resonant (left), intercombination (middle) and forbidden (right) lines. In hot stars, the forbidden-line strength of He-like ions is reduced by photoexcitation of electrons in the 3S1 state by photospheric UV radiation. We do not detect the Mg XI f line. T ...
History of X-ray astronomy
The history of X-ray astronomy begins in the 1920s, with interest in short wave communications for the U.S. Navy. This was soon followed by extensive study of the earth's ionosphere. By 1927, interest in the detection of X-ray and ultraviolet (UV) radiation at high altitudes inspired researchers to launch Goddard's rockets into the upper atmosphere to support theoretical studies and data gathering. The first successful rocket flight equipped with instrumentation able to detect solar ultraviolet radiation occurred in 1946. X-ray solar studies began in 1949. By 1973 a solar instrument package orbited on Skylab providing significant solar data.In 1965 the Goddard Space Flight Center program in X-ray astronomy was initiated with a series of balloon-borne experiments. In the 1970s this was followed by high altitude sounding rocket experiments, and that was followed by orbiting (satellite) observatories.The first rocket flight to successfully detect a cosmic source of X-ray emission was launched in 1962 by a group at American Science and Engineering (AS&E).X-ray wavelengths reveal information about the bodies (sources) that emit them.