Stellar astrophysics based on interferometry
... Effects on the main sequence • Example from Girardi et al. (2000), for low-mass stars. ...
... Effects on the main sequence • Example from Girardi et al. (2000), for low-mass stars. ...
Non-thermal emission processes in massive binaries*
... - the emission of thermal X-rays, likely produced by hydrodynamic shocks between plasma shells travelling at different velocities in the wind of isolated stars, and leading to local temperature enhancements of a few 106 K (see Feldmeier et al (1997)). The thermal nature of the X-rays produced within ...
... - the emission of thermal X-rays, likely produced by hydrodynamic shocks between plasma shells travelling at different velocities in the wind of isolated stars, and leading to local temperature enhancements of a few 106 K (see Feldmeier et al (1997)). The thermal nature of the X-rays produced within ...
![arXiv:1210.2471v1 [astro-ph.EP] 9 Oct 2012 Exoplanet Detection](http://s1.studyres.com/store/data/015975823_1-e4b4b3613f38bbff39746aa9bc12073b-300x300.png)
arXiv:1210.2471v1 [astro-ph.EP] 9 Oct 2012 Exoplanet Detection
... of the parent star. Although the emission of exoplanets is indeed quite faint, it is generally the problem of detecting this emission in the proximity of the much brighter stellar source that presents the most severe practical obstacle to direct detection. The disentangling of stellar and planetary ...
... of the parent star. Although the emission of exoplanets is indeed quite faint, it is generally the problem of detecting this emission in the proximity of the much brighter stellar source that presents the most severe practical obstacle to direct detection. The disentangling of stellar and planetary ...
S282_2 Introduction to active galaxies
... to absorb starlight. However, dust can emit strongly at farinfrared wavelengths (λ of about 100 μm). As a rule, optical absorption lines result from stars, and optical emission lines result from hot gas. The spectra of stars and HII regions extend far beyond the optical region. The Sun, for example, ...
... to absorb starlight. However, dust can emit strongly at farinfrared wavelengths (λ of about 100 μm). As a rule, optical absorption lines result from stars, and optical emission lines result from hot gas. The spectra of stars and HII regions extend far beyond the optical region. The Sun, for example, ...
– 1 – 1. Galaxy Observations 1.1.
... are that most of the stellar mass in galaxies resides in those with masses within a factor of two of ∼ 5 × 1010 M⊙ , and they find the distribution of the amplitude of the 4000 Å break is bimodal, suggesting a clear division between old and “dead” galaxies and galaxies with more recent star formati ...
... are that most of the stellar mass in galaxies resides in those with masses within a factor of two of ∼ 5 × 1010 M⊙ , and they find the distribution of the amplitude of the 4000 Å break is bimodal, suggesting a clear division between old and “dead” galaxies and galaxies with more recent star formati ...
Gravitational Lensing: An Unique Probe of Dark Matter and Dark...
... infinite magnification called critical lines. Transferred to the source plane these line become caustics. The location of these lines depends on the relative distances of the source and lens and, of course, the distribution of matter in the lens. The position of the background source with respect to ...
... infinite magnification called critical lines. Transferred to the source plane these line become caustics. The location of these lines depends on the relative distances of the source and lens and, of course, the distribution of matter in the lens. The position of the background source with respect to ...
The History of Infrared Spectroscopy
... radiation is the Planck blackbody curve. Any object that is above absolute zero will emit radiation (Figure 5) and the peak wavelength depends on the temperature, with temperatures below ~2,500 K having their peak radiation in the infrared. Thus infrared spectroscopy is particularly useful for measu ...
... radiation is the Planck blackbody curve. Any object that is above absolute zero will emit radiation (Figure 5) and the peak wavelength depends on the temperature, with temperatures below ~2,500 K having their peak radiation in the infrared. Thus infrared spectroscopy is particularly useful for measu ...
THE FINAL FATE OF STARS THAT IGNITE NEON AND OXYGEN
... simulations of thermohaline mixing (Denissenkov 2010; Traxler et al. 2011) have shown the mixing to be much less efficient, characterized by a value of a < 1. The simulations of Siess (2009), in which the carbon flame is quenched, had also assumed the same efficiency of thermohaline mixing, characte ...
... simulations of thermohaline mixing (Denissenkov 2010; Traxler et al. 2011) have shown the mixing to be much less efficient, characterized by a value of a < 1. The simulations of Siess (2009), in which the carbon flame is quenched, had also assumed the same efficiency of thermohaline mixing, characte ...
Impact of atmospheric refraction: How deeply can we probe exo
... gas (Goldsmith 1963), so that the greatest ray bending occurs in the deepest atmospheric regions. This differential refractive bending of light with altitude generally decreases the flux of a point source when observed through an atmosphere. Combined with absorption and scattering from gas and aeros ...
... gas (Goldsmith 1963), so that the greatest ray bending occurs in the deepest atmospheric regions. This differential refractive bending of light with altitude generally decreases the flux of a point source when observed through an atmosphere. Combined with absorption and scattering from gas and aeros ...
Stardust--Snapshots of Stars
... technique on the NanoSIMS that expands on automated methods developed in the early 2000s to study presolar grains . Preserved in primitive meteorites, presolar grains are literally stardust that formed in ancient stellar outflows and ejecta from supernova explosions, and became part of the molecular ...
... technique on the NanoSIMS that expands on automated methods developed in the early 2000s to study presolar grains . Preserved in primitive meteorites, presolar grains are literally stardust that formed in ancient stellar outflows and ejecta from supernova explosions, and became part of the molecular ...
Nobuyuki Kawai
... • many more target events for GW! • no regular “GRB”: how to identify? – may have delayed X-ray/optical afterglow ...
... • many more target events for GW! • no regular “GRB”: how to identify? – may have delayed X-ray/optical afterglow ...
A new view of galaxy evolution
... relaxation over a relatively quick timescale. However, the question remains as to how and why these galaxies look the way they do in the distant universe; specifically, we need to understand how they got distorted in the first place. Furthermore, kinematic studies of these galaxies show that they of ...
... relaxation over a relatively quick timescale. However, the question remains as to how and why these galaxies look the way they do in the distant universe; specifically, we need to understand how they got distorted in the first place. Furthermore, kinematic studies of these galaxies show that they of ...
The evolution and explosion of massive stars
... ⱗ8M 䉺 ) , however, no point is ever reached at which a massive star can be fully supported by electron degeneracy. Instead, the center evolves to ever higher temperatures, fusing ever heavier elements until a core of iron is produced. The collapse of this iron core to a neutron star releases an enor ...
... ⱗ8M 䉺 ) , however, no point is ever reached at which a massive star can be fully supported by electron degeneracy. Instead, the center evolves to ever higher temperatures, fusing ever heavier elements until a core of iron is produced. The collapse of this iron core to a neutron star releases an enor ...
Today The Sun Events
... – Chemical and gravitational energy sources could not explain how the Sun could sustain its luminosity for more than about 25 million years. – The Sun shines because gravitational equilibrium keeps its core hot and dense enough to release energy through nuclear fusion. • Hydrogen fuses into Helium i ...
... – Chemical and gravitational energy sources could not explain how the Sun could sustain its luminosity for more than about 25 million years. – The Sun shines because gravitational equilibrium keeps its core hot and dense enough to release energy through nuclear fusion. • Hydrogen fuses into Helium i ...
THE MONTHLY SKY GUIDE, SIXTH EDITION
... but drift at a more leisurely pace. Despite their name, shooting stars are nothing to do with stars at all. They are particles of dust shed by comets and are usually no bigger than a grain of sand. They plunge into the Earth’s atmosphere at speeds from 10 to 75 km/sec (6 to 46 mile/sec). We see a gl ...
... but drift at a more leisurely pace. Despite their name, shooting stars are nothing to do with stars at all. They are particles of dust shed by comets and are usually no bigger than a grain of sand. They plunge into the Earth’s atmosphere at speeds from 10 to 75 km/sec (6 to 46 mile/sec). We see a gl ...
publictour - LIGO Hanford Observatory
... Supernova: Death of a Massive Star •Spacequake should preceed optical display by ½ day •Leaves behind compact stellar core, e.g., neutron star, black hole •Strength of waves depends on asymmetry in collapse ...
... Supernova: Death of a Massive Star •Spacequake should preceed optical display by ½ day •Leaves behind compact stellar core, e.g., neutron star, black hole •Strength of waves depends on asymmetry in collapse ...
Turbulence-driven Polar Winds from T Tauri Stars Energized by
... • Coronal heating must be ultimately responsible for the solar wind. • A fraction of the “coronal heating” is channeled downward by conduction. • Hammer (1982) & Withbroe (1988) suggested a balance between conduction (downward), enthalpy (upward), and radiation losses (local) that sets mass flux: ...
... • Coronal heating must be ultimately responsible for the solar wind. • A fraction of the “coronal heating” is channeled downward by conduction. • Hammer (1982) & Withbroe (1988) suggested a balance between conduction (downward), enthalpy (upward), and radiation losses (local) that sets mass flux: ...
Title The molecular envelope around the red supergiant VY CMa
... a theoretical model, based on a spherically symmetric envelope, that requires time-varying mass-loss rates to reproduce previous single-dish CO multiline spectra. The high angular resolution view offered by the Submillimeter Array (SMA)1 now provides new constraints on the structure and kinematics o ...
... a theoretical model, based on a spherically symmetric envelope, that requires time-varying mass-loss rates to reproduce previous single-dish CO multiline spectra. The high angular resolution view offered by the Submillimeter Array (SMA)1 now provides new constraints on the structure and kinematics o ...
Star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as ""stellar nurseries"" or ""star-forming regions"", collapse to form stars. As a branch of astronomy, star formation includes the study of the interstellar medium (ISM) and giant molecular clouds (GMC) as precursors to the star formation process, and the study of protostars and young stellar objects as its immediate products. It is closely related to planet formation, another branch of astronomy. Star formation theory, as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.