Dark Matter Capture in the first stars
... • DM heating disassociates molecular hydrogen, and then ionizes the gas • Our proto star has now become a star. – Initial star is a few solar masses – Accrete more baryons up to the Jeans Mass~1000M ...
... • DM heating disassociates molecular hydrogen, and then ionizes the gas • Our proto star has now become a star. – Initial star is a few solar masses – Accrete more baryons up to the Jeans Mass~1000M ...
Stellar Continua
... temperature indicator • Varies smoothly with changing temperature • Slope is negative (blue is brighter) for hot stars and positive (visual is brighter) for cooler stars • B-V works as a temperature indicator from 3500K to 9000K (but depends on metallicity) • For hotter stars, neutral H and H- opaci ...
... temperature indicator • Varies smoothly with changing temperature • Slope is negative (blue is brighter) for hot stars and positive (visual is brighter) for cooler stars • B-V works as a temperature indicator from 3500K to 9000K (but depends on metallicity) • For hotter stars, neutral H and H- opaci ...
Interferometric Doppler Imaging of Chemically Peculiar stars
... Interferometric Imaging and Spectroscopy will provide unique and complementary data for understanding star and planet formation. The techniques will probe the innermost regions protoplanetary disks and will enable diameter measurements of stars still contracting to the main sequence. The science cas ...
... Interferometric Imaging and Spectroscopy will provide unique and complementary data for understanding star and planet formation. The techniques will probe the innermost regions protoplanetary disks and will enable diameter measurements of stars still contracting to the main sequence. The science cas ...
Astronomy 112: The Physics of Stars Class 17 Notes: Core Collapse
... One important effect that distinguishes the evolution of massive stars from that of lower mass stars is the importance of mass loss, both on the main sequence and thereafter. Low mass stars do not experience significant mass loss before the AGB phase, but massive stars, as we have already seen, can ...
... One important effect that distinguishes the evolution of massive stars from that of lower mass stars is the importance of mass loss, both on the main sequence and thereafter. Low mass stars do not experience significant mass loss before the AGB phase, but massive stars, as we have already seen, can ...
Variable Star Observation
... stellar system consisting of two stars orbiting around their center of mass. ...
... stellar system consisting of two stars orbiting around their center of mass. ...
ON STARS, THEIR EVOLUTION AND THEIR STABILITY
... a pressure P is zero-point energy; and the essential content of Fowler’s paper is that this zero-point energy is so great that we may expect a star to eventually settle down to a state in which all of its energy is of this kind. Fowler’s argument can be more explicitly formulated in the following ma ...
... a pressure P is zero-point energy; and the essential content of Fowler’s paper is that this zero-point energy is so great that we may expect a star to eventually settle down to a state in which all of its energy is of this kind. Fowler’s argument can be more explicitly formulated in the following ma ...
Forms Tip Sheet 9-8-14 - Virginia Cooperative Extension
... ! The forms are created in an EXCEL format and have protected cells as well as the accumulative points that will automatically add on the youth form. The unprotected cells are where the projects/act ...
... ! The forms are created in an EXCEL format and have protected cells as well as the accumulative points that will automatically add on the youth form. The unprotected cells are where the projects/act ...
The light curves for a nova look like the following.
... brightness in a sudden and explosive-like manner; the collision of two stars, core changes, unstable pulsations. However, novae are often recurrent, meaning that after 50 to 100 years the nova will go off again. This means that whatever causes the brightness changes must be cyclic (i.e. it doesn't d ...
... brightness in a sudden and explosive-like manner; the collision of two stars, core changes, unstable pulsations. However, novae are often recurrent, meaning that after 50 to 100 years the nova will go off again. This means that whatever causes the brightness changes must be cyclic (i.e. it doesn't d ...
AST1100 Lecture Notes
... or P ∝ M 2 /R4 . We remember from lecture 13-14 than for an ideal gas P ∝ ρT . Inserting this in the previous equation gives T ∝ ...
... or P ∝ M 2 /R4 . We remember from lecture 13-14 than for an ideal gas P ∝ ρT . Inserting this in the previous equation gives T ∝ ...
Hertzsprung-Russell Diagram Outline
... Hertzsprung-Russell (M_V, B-V) diagram for the 16631 single stars from the Hipparcos Catalogue with relative distance precision better than 10% and sigma_(B-V) less than or equal to 0.025 mag. Colors indicate number of stars in a cell of 0.01 mag in (B-V) and 0.05 mag in V magnitude ...
... Hertzsprung-Russell (M_V, B-V) diagram for the 16631 single stars from the Hipparcos Catalogue with relative distance precision better than 10% and sigma_(B-V) less than or equal to 0.025 mag. Colors indicate number of stars in a cell of 0.01 mag in (B-V) and 0.05 mag in V magnitude ...
Recent advances in star
... has collapsed under a higher external pressure. β is the plasma parameter (gas pressure/magnetic pressure), initially unity in the cloud. Axis scales are in parsecs, run time in Myrs and the colour scale refers to the temperature panel. Due to the magnetic field, the fast magnetosonic speed in the c ...
... has collapsed under a higher external pressure. β is the plasma parameter (gas pressure/magnetic pressure), initially unity in the cloud. Axis scales are in parsecs, run time in Myrs and the colour scale refers to the temperature panel. Due to the magnetic field, the fast magnetosonic speed in the c ...
Eclipsing binary stars
... This is the most popular and accessible method in astronomy. Photometry is the measurement of the intensity of electromagnetic radiation usually expressed in apparent magnitude. Apparent magnitude is a numerical scale to describe how bright each star appears in the sky. The lower the magnitude, the ...
... This is the most popular and accessible method in astronomy. Photometry is the measurement of the intensity of electromagnetic radiation usually expressed in apparent magnitude. Apparent magnitude is a numerical scale to describe how bright each star appears in the sky. The lower the magnitude, the ...
Chapter 5 Theory of Stellar Evolution
... contract out of the interstellar medium, and generally we avoid most of the detailed description of the final, fatal collapse of massive stars. In addition, the fascinating field of the evolution of close binary stars, where the evolution of one member of the system influences the evolution of the o ...
... contract out of the interstellar medium, and generally we avoid most of the detailed description of the final, fatal collapse of massive stars. In addition, the fascinating field of the evolution of close binary stars, where the evolution of one member of the system influences the evolution of the o ...
PoS(HTRA-IV)044 - Proceeding of science
... equation can also be written in K band, but to calculate α from K band magnitude, one needs BC in K band, which is hard to find in previous publications. From now on, we will speak about a projected apparent diameter at 40 a.u, mean distance of the classical Kuiper belt, instead of an angular diamet ...
... equation can also be written in K band, but to calculate α from K band magnitude, one needs BC in K band, which is hard to find in previous publications. From now on, we will speak about a projected apparent diameter at 40 a.u, mean distance of the classical Kuiper belt, instead of an angular diamet ...
determining stellar parameters from star`s
... With help of the eq. (1.1) we can calculate the temperature of the sun. But not everything is as straightforward as it seems. In figure 1.1 we compare the energy curve observed from the sun with a theoretical curve for a temperature of 5800K. Although the shapes of the two curves are somewhat simila ...
... With help of the eq. (1.1) we can calculate the temperature of the sun. But not everything is as straightforward as it seems. In figure 1.1 we compare the energy curve observed from the sun with a theoretical curve for a temperature of 5800K. Although the shapes of the two curves are somewhat simila ...
Properties of Stars - Montana State University Extended University
... 7. What are two reasons why determining a star's temperature from Wien's law (see the electromagnetic radiation chapter) is usually not as accurate as using the spectral lines? 8. What are the 7 basic spectral types in order of temperature (hottest to coldest)? 9. If our Sun has a surface temperatur ...
... 7. What are two reasons why determining a star's temperature from Wien's law (see the electromagnetic radiation chapter) is usually not as accurate as using the spectral lines? 8. What are the 7 basic spectral types in order of temperature (hottest to coldest)? 9. If our Sun has a surface temperatur ...
Sternentstehung - Star Formation
... - Hayashi tracks: Shrinking releases grav. energy & Tsurface approx. constant - L = 4πR2σBTeff4 ∝ R*2 à L decreases à L falls below Lcrit. à Radiative core forms again with a shrinking outer convective layer. - During further slow contraction internal energy, temperature & luminosity rise again unti ...
... - Hayashi tracks: Shrinking releases grav. energy & Tsurface approx. constant - L = 4πR2σBTeff4 ∝ R*2 à L decreases à L falls below Lcrit. à Radiative core forms again with a shrinking outer convective layer. - During further slow contraction internal energy, temperature & luminosity rise again unti ...
Star Clusters and Stellar Dynamics
... energy amongst themselves. If at some moment a star becomes unbound (kinetic + potential energy > 0) then it will escape the cluster entirely. Evaporation time tevap ~ 100 trelax , and although long, it limits the cluster lifetime. Evaporation is accelerated by tidal shocks, which implant additional ...
... energy amongst themselves. If at some moment a star becomes unbound (kinetic + potential energy > 0) then it will escape the cluster entirely. Evaporation time tevap ~ 100 trelax , and although long, it limits the cluster lifetime. Evaporation is accelerated by tidal shocks, which implant additional ...
The Main Sequence - University of Arizona
... • Steady mass loss (neither of the cases pictured above) usually driven by absorption of photons in bound-bound transitions of metal lines Ý is metallicity dependent – most transitions in metal atoms, so M – depends on current surface z, so self enrichment important – depends on rotation - higher te ...
... • Steady mass loss (neither of the cases pictured above) usually driven by absorption of photons in bound-bound transitions of metal lines Ý is metallicity dependent – most transitions in metal atoms, so M – depends on current surface z, so self enrichment important – depends on rotation - higher te ...
The Helium Flash • When the temperature of a stellar core reaches T
... • During helium core burning, the radius of the helium core will remain approximately constant. The core will not contract until the helium fraction reaches Y < 0.1. Once it does, the star will restructure itself in a manner similar to that of the hydrogenexhaustion phase. First, the stellar core w ...
... • During helium core burning, the radius of the helium core will remain approximately constant. The core will not contract until the helium fraction reaches Y < 0.1. Once it does, the star will restructure itself in a manner similar to that of the hydrogenexhaustion phase. First, the stellar core w ...
PowerPoint Presentation - Mullard Space Science Laboratory
... SGRB in the first hundred seconds is ~ 1050 erg. LGRB are a few hundreds to a few thousand times more energetic. Now there are evidences that LGRB are associated with violent explosions of massive stars [13,14], while SGRB are believed to be caused by compact-star merging. Here, we consider various ...
... SGRB in the first hundred seconds is ~ 1050 erg. LGRB are a few hundreds to a few thousand times more energetic. Now there are evidences that LGRB are associated with violent explosions of massive stars [13,14], while SGRB are believed to be caused by compact-star merging. Here, we consider various ...