The new X-ray universe
... Seyfert 1.5 galaxy NGC 4151 shows evidence for both photoionized and collisionally ionized material in a multicomponent narrow line region. The emission line spectrum of the Seyfert 2 galaxy NGC 1068 looks remarkably similar to that of NGC 4151, but with a relatively weaker continuum. The spectra of ...
... Seyfert 1.5 galaxy NGC 4151 shows evidence for both photoionized and collisionally ionized material in a multicomponent narrow line region. The emission line spectrum of the Seyfert 2 galaxy NGC 1068 looks remarkably similar to that of NGC 4151, but with a relatively weaker continuum. The spectra of ...
Do flares in Saggitarius A* reflect the last stage of tidal capture
... most transparent material available – hydrogen at a high enough temperature -, so that its opacity is due only to Thomson scattering (k = 0.4cm2/g), and assume that photons are loosing no energy when diffusively scattering to the surface. Then: tg = (1/c) (k M/R), or ...
... most transparent material available – hydrogen at a high enough temperature -, so that its opacity is due only to Thomson scattering (k = 0.4cm2/g), and assume that photons are loosing no energy when diffusively scattering to the surface. Then: tg = (1/c) (k M/R), or ...
Summary of Cool Stars 13 - JILA - University of Colorado Boulder
... rotate as solid bodies at M1-2V. So, the alpha effect must dominate magnetic field generation in M dwarfs. • Michael Weber (P): Study of differential rotation of 5 RS CVn-type giants using time series Doppler images shows that some stars are solar-like (equator faster than pole) and some are reverse ...
... rotate as solid bodies at M1-2V. So, the alpha effect must dominate magnetic field generation in M dwarfs. • Michael Weber (P): Study of differential rotation of 5 RS CVn-type giants using time series Doppler images shows that some stars are solar-like (equator faster than pole) and some are reverse ...
Who’s Afraid of a Stellar Superflare? Rachel Osten GSFC
... 1033-1038 ergs, occurring roughly once every 100 years or so ...
... 1033-1038 ergs, occurring roughly once every 100 years or so ...
EXTREME NEUTRON STARS Christopher Thompson Canadian Institute for Theoretical Astrophysics University of Toronto
... Helicity Injection into the Magnetosphere Actively bursting magnetars show: Strong non-thermal X-ray emission when not bursting Long term (up to years) stable variations in X-ray ...
... Helicity Injection into the Magnetosphere Actively bursting magnetars show: Strong non-thermal X-ray emission when not bursting Long term (up to years) stable variations in X-ray ...
GEARS Workshop Monday - Georgia Southern University
... The Chandra data shows bright X-ray sources in this field, most of which are young stars. In this image, red, green, and blue represent low, medium, and high energy X-rays. The Chandra data have been overlaid on the Hubble Space Telescope image to show the context of these X-ray data. Very few X-ray ...
... The Chandra data shows bright X-ray sources in this field, most of which are young stars. In this image, red, green, and blue represent low, medium, and high energy X-rays. The Chandra data have been overlaid on the Hubble Space Telescope image to show the context of these X-ray data. Very few X-ray ...
Puzzling X-rays from the new colliding wind binary Wolf–Rayet 65
... has a period of a few days: the two data points obtained in 2003 April indicate constant count rates over at least a week. Moreover, two data points in the light curve separated by two months (2004 December and 2005 February) are similar, while there is an increase in emission by nearly 70 per cent ...
... has a period of a few days: the two data points obtained in 2003 April indicate constant count rates over at least a week. Moreover, two data points in the light curve separated by two months (2004 December and 2005 February) are similar, while there is an increase in emission by nearly 70 per cent ...
File
... Density of gas color coded by temperature. Yellow circles represent black holes. Dark matter and stars are not shown in this plot. ...
... Density of gas color coded by temperature. Yellow circles represent black holes. Dark matter and stars are not shown in this plot. ...
X-ray emission and the incidence of magnetic fields in the massive
... field strength in a detection case, and provide upper limits for a nondetection. We sampled the 4-dimensional parameter space (i, β, φ, B) which describes a centered dipolar magnetic configuration. i is the projected angle of the rotation axis, β is the angle between the magnetic axis and the rotati ...
... field strength in a detection case, and provide upper limits for a nondetection. We sampled the 4-dimensional parameter space (i, β, φ, B) which describes a centered dipolar magnetic configuration. i is the projected angle of the rotation axis, β is the angle between the magnetic axis and the rotati ...
X-ray Emission Line Profile Diagnostics of Hot Star Winds
... Although there’s not good reason to think that these young O stars have convection or magnetic dynamos, they may have magnetic fields that remain from the the collapsing interstellar clouds out of which they formed In fact, q1 Ori C itself has recently had a magnetic field detected on it: A large s ...
... Although there’s not good reason to think that these young O stars have convection or magnetic dynamos, they may have magnetic fields that remain from the the collapsing interstellar clouds out of which they formed In fact, q1 Ori C itself has recently had a magnetic field detected on it: A large s ...
zaneposter
... and the Soft Gamma-ray Repeaters (SGRs), two classes of sources observationally very similar in many respects (see Mereghetti et al. 2008 for a review).They are all slow X-ray pulsars with spin periods clustered in a narrow range (P ~ 2-12 s), relatively large period derivatives (dP/dt ~ 10-13 -10-1 ...
... and the Soft Gamma-ray Repeaters (SGRs), two classes of sources observationally very similar in many respects (see Mereghetti et al. 2008 for a review).They are all slow X-ray pulsars with spin periods clustered in a narrow range (P ~ 2-12 s), relatively large period derivatives (dP/dt ~ 10-13 -10-1 ...
Barger - Chandra X-Ray Observatory (CXC)
... • Deep MIR and radio images are an obvious avenue for searching for highly-obscured AGNs, since extinction in the MIR & radio is small • People have tried to use combined MIR & radio selections, but to obtain a reliable upper limit on the possible population of X-ray undetected, obscured AGNs, a cle ...
... • Deep MIR and radio images are an obvious avenue for searching for highly-obscured AGNs, since extinction in the MIR & radio is small • People have tried to use combined MIR & radio selections, but to obtain a reliable upper limit on the possible population of X-ray undetected, obscured AGNs, a cle ...
AMUSE-Virgo Super-massive black holes vs. nuclear star clusters: the X-ray view
... Stellar Nuclear ...
... Stellar Nuclear ...
Unique observations of a newborn star provide information on the
... more special was the fact that it appears to be an extremely young star – far less than a million years old – about the same mass as the sun. Astronomers know of fewer David Weintraub ...
... more special was the fact that it appears to be an extremely young star – far less than a million years old – about the same mass as the sun. Astronomers know of fewer David Weintraub ...
The Satellites of Uranus and Neptune: A New Astrometrie Programme
... to share common envelopes which are likely areas from which X-rays may be emitted. It is from such photographs that a detailed morphological study of the region can be made. ...
... to share common envelopes which are likely areas from which X-rays may be emitted. It is from such photographs that a detailed morphological study of the region can be made. ...
PowerPoint Presentation - Super Massive Black Holes
... Most Black Holes are believed to come about from the death of massive stars. ...
... Most Black Holes are believed to come about from the death of massive stars. ...
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... The discovery of the mechanism of fasting and feasting process is the breakthrough that many were looking forward to and given important inputs for further theoretical understanding of these binaries. Says Dr Bhalerao: “This allows us to better understand how massive stars form, to study how binarie ...
... The discovery of the mechanism of fasting and feasting process is the breakthrough that many were looking forward to and given important inputs for further theoretical understanding of these binaries. Says Dr Bhalerao: “This allows us to better understand how massive stars form, to study how binarie ...
Fitting X-ray Spectra with Imperfect Models
... information on heating, dynamics, feedback. • Atomic rate uncertainties > calibration and statistical errors. • Uncertainties in the charge state balance can lead to inconsistencies in global models. • Residuals near strong lines are likely related to atomic rate uncertainties. Complex absorption ef ...
... information on heating, dynamics, feedback. • Atomic rate uncertainties > calibration and statistical errors. • Uncertainties in the charge state balance can lead to inconsistencies in global models. • Residuals near strong lines are likely related to atomic rate uncertainties. Complex absorption ef ...
Shockingly Bright Pulsar - Astronomical Society of the Pacific
... (NuSTAR) is the first satellite to focus high-energy X-rays into sharp images. It includes two focusing X-ray telescopes which capture images, and also measure the energy of each incoming X-ray. Essential to the NuSTAR design is a deployable mast which extended to 10 meters after launch. This mast s ...
... (NuSTAR) is the first satellite to focus high-energy X-rays into sharp images. It includes two focusing X-ray telescopes which capture images, and also measure the energy of each incoming X-ray. Essential to the NuSTAR design is a deployable mast which extended to 10 meters after launch. This mast s ...
The Chandra Orion Ultradeep Project Eric Feigelson
... But none of these variations coincide with X-ray flares ...
... But none of these variations coincide with X-ray flares ...
X-ray output should be time variable
... Bright stars in the spectral range earlier than about B3 are soft X-ray sources, with LX ~ 10-7 LBol THEORY •O star X-ray emission comes from shock-heated gas present in their stellar winds; for B stars, the situation is more uncertain, and their Xrays may be related to magnetic fields, at least in ...
... Bright stars in the spectral range earlier than about B3 are soft X-ray sources, with LX ~ 10-7 LBol THEORY •O star X-ray emission comes from shock-heated gas present in their stellar winds; for B stars, the situation is more uncertain, and their Xrays may be related to magnetic fields, at least in ...
X-ray binaries
... companion star or the interstellar medium, its magnetic field becomes dynamically important close to the stellar surface and determines the properties of the accretion flow. The radius at which the effects of the magnetic field dominate all others is called the Alfven radius. • For thin-disk accretion o ...
... companion star or the interstellar medium, its magnetic field becomes dynamically important close to the stellar surface and determines the properties of the accretion flow. The radius at which the effects of the magnetic field dominate all others is called the Alfven radius. • For thin-disk accretion o ...
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.