Zhu Qualifier Solutions - University of Toronto Astronomy
... 1.7.2. Why can’t we explain the Hubble flow through the physical motion of galaxies through space? 1.7.3. Can galaxies with recession velocities v > c slow down until v < c? ...
... 1.7.2. Why can’t we explain the Hubble flow through the physical motion of galaxies through space? 1.7.3. Can galaxies with recession velocities v > c slow down until v < c? ...
Runaway collisions in young star clusters – II. Numerical results
... population, the average mass is M∗ 0.69 M . There is no initial mass segregation. To investigate the role of the initial concentration of the cluster, we consider King models with W0 = 3 or 8 (Binney & Tremaine 1987, Section 4.4). We do not enforce tidal truncation because it was shown in GFR0 ...
... population, the average mass is M∗ 0.69 M . There is no initial mass segregation. To investigate the role of the initial concentration of the cluster, we consider King models with W0 = 3 or 8 (Binney & Tremaine 1987, Section 4.4). We do not enforce tidal truncation because it was shown in GFR0 ...
Leaky Stars: Pulsations, Waves, and Turbulence in Stellar Winds
... across the H-R Diagram • The Sun: coronal heating & fast solar wind • Hot stars (O, B, W-R): pulsations & radiation-driving • Cool stars (T Tau, Mira): chromospheric flows? Steven R. Cranmer & many others ...
... across the H-R Diagram • The Sun: coronal heating & fast solar wind • Hot stars (O, B, W-R): pulsations & radiation-driving • Cool stars (T Tau, Mira): chromospheric flows? Steven R. Cranmer & many others ...
A non-grey analytical model for irradiated atmospheres.
... of opacities because of its very extensive use both in the context of giant exoplanets and brown dwarfs, i.e.,the solar-composition opacities provided by Freedman et al. (2008). These opacities have been calculated for a solar-composition mixture in chemical equilibrium. They do not account for the ...
... of opacities because of its very extensive use both in the context of giant exoplanets and brown dwarfs, i.e.,the solar-composition opacities provided by Freedman et al. (2008). These opacities have been calculated for a solar-composition mixture in chemical equilibrium. They do not account for the ...
Classical Oe Stars in the Field of the Small Magellanic Cloud
... suggesting that Be stars may rotate closer to vcrit than observations find. Determining how Be stars form with subcritical rotation rates led to the viscous decretion disk model (VDD; Lee et al. 1991). This model proposes that processes such as non-radial pulsation (NRP) spin up the stellar atmosphe ...
... suggesting that Be stars may rotate closer to vcrit than observations find. Determining how Be stars form with subcritical rotation rates led to the viscous decretion disk model (VDD; Lee et al. 1991). This model proposes that processes such as non-radial pulsation (NRP) spin up the stellar atmosphe ...
Chapter 5 - Leiden Observatory
... Zwart & Yungelson, 1998]. Following mass transfer in a binary, the donor may turn into a helium-burning star without hydrogen envelope. When the mass transfer leads to a merger between the binary stars, we estimate the resulting stellar product and follow the evolution further. Note that we do not s ...
... Zwart & Yungelson, 1998]. Following mass transfer in a binary, the donor may turn into a helium-burning star without hydrogen envelope. When the mass transfer leads to a merger between the binary stars, we estimate the resulting stellar product and follow the evolution further. Note that we do not s ...
Evolution and fate of very massive stars
... In Figs. 3, 4 and 5, we present the evolutionary tracks of our present models with initial masses between 150 and 500 M for the three metallicities considered. Other properties of the present stellar models are given at various evolutionary stages in Tables 3, 4 and 5. A very first striking feature ...
... In Figs. 3, 4 and 5, we present the evolutionary tracks of our present models with initial masses between 150 and 500 M for the three metallicities considered. Other properties of the present stellar models are given at various evolutionary stages in Tables 3, 4 and 5. A very first striking feature ...
Population synthesis for symbiotic stars with white dwarf accretors
... rithm for angular momentum loss during the commonenvelope stages of evolution; Winters and his collaborators (Winters et al. 2000, 2002, 2003) studied the hydrodynamical structure of the stellar wind around AGB stars with low mass-loss rate and low wind outflow velocity. New observational catalogue a ...
... rithm for angular momentum loss during the commonenvelope stages of evolution; Winters and his collaborators (Winters et al. 2000, 2002, 2003) studied the hydrodynamical structure of the stellar wind around AGB stars with low mass-loss rate and low wind outflow velocity. New observational catalogue a ...
Differential rotation of main sequence F stars
... In Fig. 1 the rotation rate is plotted vs. radius for latitudes at 0◦ (equator), 15, 30, 45, 60, 75, and 90◦ (poles). In all cases the equator rotates faster than the poles (solar-type differential rotation), but the amplitude of the relative shear varies with the rotation rate. The model with the f ...
... In Fig. 1 the rotation rate is plotted vs. radius for latitudes at 0◦ (equator), 15, 30, 45, 60, 75, and 90◦ (poles). In all cases the equator rotates faster than the poles (solar-type differential rotation), but the amplitude of the relative shear varies with the rotation rate. The model with the f ...
variable star type designations in vsx
... Spotted stars that weren't classified into a particular class. All the SPOTTED stars in the UNSW list and the very small amplitude spotted stars found by Kepler are included here. Also, some stars that don't fit the current subtypes due to their physical properties have been classified as such (brow ...
... Spotted stars that weren't classified into a particular class. All the SPOTTED stars in the UNSW list and the very small amplitude spotted stars found by Kepler are included here. Also, some stars that don't fit the current subtypes due to their physical properties have been classified as such (brow ...
Str\" omgren uvby photometry of the peculiar globular cluster NGC
... remains ambiguous, as this morphological class likely constitutes a mixture of stripped nuclei and of massive genuine star clusters (see Frank 2014, for a recent review). In contrast to ω Cen (NGC 5139) or M54, which are thought to be remnant nuclei of accreted satellites and which have broad metall ...
... remains ambiguous, as this morphological class likely constitutes a mixture of stripped nuclei and of massive genuine star clusters (see Frank 2014, for a recent review). In contrast to ω Cen (NGC 5139) or M54, which are thought to be remnant nuclei of accreted satellites and which have broad metall ...
Symbiotic Stars as Laboratories for the Study of
... Abstract Symbiotic binary stars typically consist of a white dwarf (WD) that accretes material from the wind of a companion red giant. Orbital periods for these binaries are on the order of years, and their relatively small optical outbursts tend to occur every few years to decades. In some symbioti ...
... Abstract Symbiotic binary stars typically consist of a white dwarf (WD) that accretes material from the wind of a companion red giant. Orbital periods for these binaries are on the order of years, and their relatively small optical outbursts tend to occur every few years to decades. In some symbioti ...
Envelope inflation in massive stars near the Eddington limit
... Solar chemical composition, the minimum initial mass of massive stars correspond to ∼ 9 M (Poelarends et al. 2008). In the course of their evolution, massive stars appear as blue/red supergiants, Luminous Blue Variables (Sec. 1.2.2) and Wolf-Rayet stars (Sec. 1.2.3), depending on their mass and mas ...
... Solar chemical composition, the minimum initial mass of massive stars correspond to ∼ 9 M (Poelarends et al. 2008). In the course of their evolution, massive stars appear as blue/red supergiants, Luminous Blue Variables (Sec. 1.2.2) and Wolf-Rayet stars (Sec. 1.2.3), depending on their mass and mas ...
Galactic astroarchaeology: reconstructing the bulge history by
... Fig. 1. Comparison between the predictions of our model using 3 different IMF for [O/Fe], [Mg/Fe], [Si/Fe], and [S/Fe] vs. [Fe/H] and the observations in the bulge. The observational data for the bulge are filled circles from MFR09 and FMR07, the open triangles from Lecureur et al. (2007), the fille ...
... Fig. 1. Comparison between the predictions of our model using 3 different IMF for [O/Fe], [Mg/Fe], [Si/Fe], and [S/Fe] vs. [Fe/H] and the observations in the bulge. The observational data for the bulge are filled circles from MFR09 and FMR07, the open triangles from Lecureur et al. (2007), the fille ...
LATE STAGES OF CLOSE BINARY SYSTEMS 1. Introduction The X
... The subsequent evolution of the system, now consisting of a helium star and an unevolved main-sequence star, depends on the mass of the helium star. Two cases are possible: (i) If the helium star has a mass below 1 AM® (the Chandrasekhar limit) it can, without difficulty, finish as a white dwarf. A1 ...
... The subsequent evolution of the system, now consisting of a helium star and an unevolved main-sequence star, depends on the mass of the helium star. Two cases are possible: (i) If the helium star has a mass below 1 AM® (the Chandrasekhar limit) it can, without difficulty, finish as a white dwarf. A1 ...
Z - STScI
... Zampieri et al., Nomoto et al - low luminosity SNe form black-holes No evidence so far of the branching at high luminosity Detailed comparison with models now possible ...
... Zampieri et al., Nomoto et al - low luminosity SNe form black-holes No evidence so far of the branching at high luminosity Detailed comparison with models now possible ...
JET FORMATION FROM MASSIVE YOUNG STARS
... compared to later stages. Our paper investigates various physical processes that impact the outflow dynamics, i.e., its acceleration and collimation. We perform axisymmetric magnetohydrodynamic (MHD) simulations particularly considering the radiation pressure exerted by the star and the disk. We hav ...
... compared to later stages. Our paper investigates various physical processes that impact the outflow dynamics, i.e., its acceleration and collimation. We perform axisymmetric magnetohydrodynamic (MHD) simulations particularly considering the radiation pressure exerted by the star and the disk. We hav ...
ON THE ORIGIN OF THE SALPETER SLOPE FOR THE INITIAL
... both the parent ICMF equipartition arguments and buildup from simple accretion. So then why is the Salpeter slope of the IMF slightly steeper than γ = 2? Elmegreen (2009) summarizes the three approaches to generating the IMF: (1) fragmentation, in which the core mass function and IMF are a direct ma ...
... both the parent ICMF equipartition arguments and buildup from simple accretion. So then why is the Salpeter slope of the IMF slightly steeper than γ = 2? Elmegreen (2009) summarizes the three approaches to generating the IMF: (1) fragmentation, in which the core mass function and IMF are a direct ma ...
A Simple Model for r-Process Scatter and Halo Evolution
... 3. The placement of a star between these extremes quantifies a admixture of nucleosynthesis sources recorded in the star. Thus, (a) at the very earliest times, when single SN events are really all that contaminate a given star, the r/Fe scatter should only populate the extremes. (b) At later times, ...
... 3. The placement of a star between these extremes quantifies a admixture of nucleosynthesis sources recorded in the star. Thus, (a) at the very earliest times, when single SN events are really all that contaminate a given star, the r/Fe scatter should only populate the extremes. (b) At later times, ...
Modeling the Point Spread Function Using Principal
... Compared to a pixel on a charge-coupled device (CCD), the common detector in modern telescope cameras, which has an angular size on the order of 0.1–0.2 arcsec for most cameras, stars are seen as point sources. Because of this point source nature, the light from stars should fall onto a single pixel ...
... Compared to a pixel on a charge-coupled device (CCD), the common detector in modern telescope cameras, which has an angular size on the order of 0.1–0.2 arcsec for most cameras, stars are seen as point sources. Because of this point source nature, the light from stars should fall onto a single pixel ...
How plausible are the proposed formation scenarios of CEMP
... Our observational sample is based on the SAGA database of stellar abundances (Suda et al. 2008, 2011, last updated August 2015), which is arguably the richest collection of heavy-element abundances currently available and includes 1944 MP stars with [Fe/H] < −1. Stars with higher iron abundances in ...
... Our observational sample is based on the SAGA database of stellar abundances (Suda et al. 2008, 2011, last updated August 2015), which is arguably the richest collection of heavy-element abundances currently available and includes 1944 MP stars with [Fe/H] < −1. Stars with higher iron abundances in ...
Molecular Cloud Evolution II. From cloud formation to the early
... collapsing globally, converting most of its mass to stars. Since stellar energy feedback is not included, our simulations probably cease to be realistic when the total mass in stars is so large that enough massive stars should exist to disrupt the cloud. Our simulations show that: a) The clouds are ...
... collapsing globally, converting most of its mass to stars. Since stellar energy feedback is not included, our simulations probably cease to be realistic when the total mass in stars is so large that enough massive stars should exist to disrupt the cloud. Our simulations show that: a) The clouds are ...
UNIVERSITY OF PADUA Master degree in
... no electric dipole moment. This means that the lowest line transition occurs in the rotational-vibrational J = 2 → 0 transition, which is faint because of its quadrupole origin [10]. The J = 2 state for molecular hydrogen is 511 K above the ground state. Since typical temperatures of regions of mole ...
... no electric dipole moment. This means that the lowest line transition occurs in the rotational-vibrational J = 2 → 0 transition, which is faint because of its quadrupole origin [10]. The J = 2 state for molecular hydrogen is 511 K above the ground state. Since typical temperatures of regions of mole ...
What causes the large extensions of red supergiant
... Likewise, the 3D convection models and the 1D pulsation models with typical parameters of RSGs lead to compact atmospheric structures as well, which are similar to the structure of the hydrostatic PHOENIX models. They can also not explain the observed decreases in the visibilities and thus the large ...
... Likewise, the 3D convection models and the 1D pulsation models with typical parameters of RSGs lead to compact atmospheric structures as well, which are similar to the structure of the hydrostatic PHOENIX models. They can also not explain the observed decreases in the visibilities and thus the large ...
First axion bounds from a pulsating helium
... particles to dark matter is dependent on their mass (or coupling constant). However, the models do not provide information about the value of the axion mass, and therefore it has to be inferred from observations. In particular, stars can be employed to place constraints on the mass of the axion [8, ...
... particles to dark matter is dependent on their mass (or coupling constant). However, the models do not provide information about the value of the axion mass, and therefore it has to be inferred from observations. In particular, stars can be employed to place constraints on the mass of the axion [8, ...