Fulltext
... choose to stay inside a bubble (“bag”) in order to minimize the total energy of the system. (If such bubble does not exist, quarks will first dig a bubble and then stay inside it.) To obey Pauli exclusion principle for fermions, we may adopt the Thomas-Fermi approximation to treat contributions from ...
... choose to stay inside a bubble (“bag”) in order to minimize the total energy of the system. (If such bubble does not exist, quarks will first dig a bubble and then stay inside it.) To obey Pauli exclusion principle for fermions, we may adopt the Thomas-Fermi approximation to treat contributions from ...
Recycling strange stars to millisecond periods
... absorption of neutrons by strange matter, and their fusion with strange matter in a strong-interaction process n −→ 2d + u, followed by the weak-interaction process u + d −→ s + u. These reactions lead to an additional heat release (deconfinement heating) at the crust-strange matter interface, of so ...
... absorption of neutrons by strange matter, and their fusion with strange matter in a strong-interaction process n −→ 2d + u, followed by the weak-interaction process u + d −→ s + u. These reactions lead to an additional heat release (deconfinement heating) at the crust-strange matter interface, of so ...
WHAT MAKES A STAR SO SPECIAL Abstract
... equally distributed according to their spectral class and luminosity. For every star with high luminosity from class B or O there are 350 stars from class A or K with average luminosity, or 1000 red stars from class M with low luminosity. This statistics shows that the formation of stars with low ma ...
... equally distributed according to their spectral class and luminosity. For every star with high luminosity from class B or O there are 350 stars from class A or K with average luminosity, or 1000 red stars from class M with low luminosity. This statistics shows that the formation of stars with low ma ...
Overview spherical accretion
... A simple example of an incompressible flow in phase space is provided by an idealized marathon race in which all runners travel at constant speed. At the start of the course, the density of runners is large, but they travel at a wide variety of speeds; at the finish, the density is low, but at any g ...
... A simple example of an incompressible flow in phase space is provided by an idealized marathon race in which all runners travel at constant speed. At the start of the course, the density of runners is large, but they travel at a wide variety of speeds; at the finish, the density is low, but at any g ...
Stellar evolution - Statistical Physics Group
... the dimensions of the clusters are usually small compared with their distances from the Earth it is a good approximation to suppose that all members of the cluster are equidistant from us and to use H R diagrams in terms of apparent luminosities instead of absolute luminosities. Finally, the stars i ...
... the dimensions of the clusters are usually small compared with their distances from the Earth it is a good approximation to suppose that all members of the cluster are equidistant from us and to use H R diagrams in terms of apparent luminosities instead of absolute luminosities. Finally, the stars i ...
ASTR 1101-001 Spring 2008 - Louisiana State University
... • Moderately Low-Mass Stars (like the Sun) (0.4 Msun M* 4 Msun) ...
... • Moderately Low-Mass Stars (like the Sun) (0.4 Msun M* 4 Msun) ...
Young Stellar Objects in the Orion B Cloud
... is 28 %, which, after a correction for contamination with field stars, is more like ~ 20 %. This, as well as the overall shape of the mass function, is remarkably similar to the Orion Trapezium KLF, which has been reported to have a fraction of substellar objects of ~ 22 % (Muench et al. 2002). We c ...
... is 28 %, which, after a correction for contamination with field stars, is more like ~ 20 %. This, as well as the overall shape of the mass function, is remarkably similar to the Orion Trapezium KLF, which has been reported to have a fraction of substellar objects of ~ 22 % (Muench et al. 2002). We c ...
Kinetic equilibrium of iron in the atmospheres of cool stars
... present approach to the analysis of the reference stars is based on a number of assumptions. Atmospheric models are calculated for all stars (including the Sun) according to the same type of input parameters, boundary conditions, and constraint equations. We thus intentionally avoid the use of empir ...
... present approach to the analysis of the reference stars is based on a number of assumptions. Atmospheric models are calculated for all stars (including the Sun) according to the same type of input parameters, boundary conditions, and constraint equations. We thus intentionally avoid the use of empir ...
hydrogen deficient stars and related objects
... intermediate helium stars may be the result of diffusion. At least, this subgroup of intermediate helium stars, which has near main sequence star masses, is intimately related to the Ap-stars. However, as we do not want to reiterate the Ap-star physics, a topic that has been dealt with abundantly in ...
... intermediate helium stars may be the result of diffusion. At least, this subgroup of intermediate helium stars, which has near main sequence star masses, is intimately related to the Ap-stars. However, as we do not want to reiterate the Ap-star physics, a topic that has been dealt with abundantly in ...
Astronomy 104: Stellar Astronomy
... core contracts (slowly at first) and heats up and heats up and heats up... •But this time, heating up can’t trigger new fusion process → core collapses under gravity... ...
... core contracts (slowly at first) and heats up and heats up and heats up... •But this time, heating up can’t trigger new fusion process → core collapses under gravity... ...
DISCOVERY OF HOT SUPERGIANT STARS NEAR THE GALACTIC
... than in the Galactic disk, this may result in the production of a population of Galactic center HMXBs, in excess of the number predicted to exist from population synthesis models (Pfahl et al. 2002). These models are based on uncertain assumptions about the angular momentum lost during the common-en ...
... than in the Galactic disk, this may result in the production of a population of Galactic center HMXBs, in excess of the number predicted to exist from population synthesis models (Pfahl et al. 2002). These models are based on uncertain assumptions about the angular momentum lost during the common-en ...
Life Histories Of Some Stars
... graph? Where do newborn babies cluster? Children? Or is there no clustering at all? Describe the shape of the graph? Is it a straight line? A curve? 5. Give each group the list of stars attached and the HR diagram attached. Instead of height and weight, the information is in Luminosity (compared to ...
... graph? Where do newborn babies cluster? Children? Or is there no clustering at all? Describe the shape of the graph? Is it a straight line? A curve? 5. Give each group the list of stars attached and the HR diagram attached. Instead of height and weight, the information is in Luminosity (compared to ...
400 Years of Stellar Rotation
... on the Sun was followed by: rotation and chemical abundances; rotation, activity and planets; and the conference ended with sessions devoted to the legacy of space missions and to our understanding of stellar rotation. The conference also featured two enlightening talks about Galileo and his cultur ...
... on the Sun was followed by: rotation and chemical abundances; rotation, activity and planets; and the conference ended with sessions devoted to the legacy of space missions and to our understanding of stellar rotation. The conference also featured two enlightening talks about Galileo and his cultur ...
The spectroscopic Hertzsprung
... Aims. We introduce a new diagram based on the gravity-effective temperature diagram, which has various advantages. Methods. Our spectroscopic Hertzsprung-Russell (sHR) diagram shows the inverse of the flux-mean gravity versus the effective temperature. Observed stars whose spectra have been quantita ...
... Aims. We introduce a new diagram based on the gravity-effective temperature diagram, which has various advantages. Methods. Our spectroscopic Hertzsprung-Russell (sHR) diagram shows the inverse of the flux-mean gravity versus the effective temperature. Observed stars whose spectra have been quantita ...
A seismic and gravitationally-bound double star observed by Kepler
... Solar-type stars have been observed over periods exceeding six months using CoRoT and Kepler providing many lists of mode frequencies required for seismic analysis (See Appourchaux et al. 2012, and references therein). Additional invaluable information about the evolution of stars is provided by the ...
... Solar-type stars have been observed over periods exceeding six months using CoRoT and Kepler providing many lists of mode frequencies required for seismic analysis (See Appourchaux et al. 2012, and references therein). Additional invaluable information about the evolution of stars is provided by the ...
ex-lup-v3
... Table on the right created at UR IR Lab, B & L 427, (i) Ábrahám, P.; Juhász, A.; Dullemond, C. P.; Kóspál, Á.; van Boekel, R.; Bouwman, J.; Henning, Th.; Moór, A.; Mosoni, L.; Sicilia-Aguilar, A.; Sipos, N. Episodic formation of cometary material in the outburst of a young Sun-like star, Nature, Vol ...
... Table on the right created at UR IR Lab, B & L 427, (i) Ábrahám, P.; Juhász, A.; Dullemond, C. P.; Kóspál, Á.; van Boekel, R.; Bouwman, J.; Henning, Th.; Moór, A.; Mosoni, L.; Sicilia-Aguilar, A.; Sipos, N. Episodic formation of cometary material in the outburst of a young Sun-like star, Nature, Vol ...
Document
... accretion, onto the surface of star 2 (with radius = R2) and the energy of the incoming material is thermalised? The energy supply ~ PE ~ GM2/R2 per unit mass, and the luminosity ~ GM2(dM/dt)/R2 ~ 4πσR22 T4 which is essentially black body radiation from the surface of the second star. If the situati ...
... accretion, onto the surface of star 2 (with radius = R2) and the energy of the incoming material is thermalised? The energy supply ~ PE ~ GM2/R2 per unit mass, and the luminosity ~ GM2(dM/dt)/R2 ~ 4πσR22 T4 which is essentially black body radiation from the surface of the second star. If the situati ...
A Modern Search for Wolf-Rayet Stars in the Magellanic Clouds. III
... (Massey et al. 2003) and 134 were known in the LMC (Breysacher et al. 1999). These stars had been found by a combination of general objective prism surveys, directed searches, and accidental discoveries by spectroscopy (see Massey 2013; Massey et al. 2015b). However, over the years several additiona ...
... (Massey et al. 2003) and 134 were known in the LMC (Breysacher et al. 1999). These stars had been found by a combination of general objective prism surveys, directed searches, and accidental discoveries by spectroscopy (see Massey 2013; Massey et al. 2015b). However, over the years several additiona ...
Ercolano et al. 2009 - Institute of Astronomy
... Questions can only be answered if a solid theoretical framework can be built to match the observational constraints available. 1) Efficient, multidimensional and frequency resolved radiative transfer coupled to hydrodynamic needed 2) Codes must be able to simulate the observed light – ionisation as ...
... Questions can only be answered if a solid theoretical framework can be built to match the observational constraints available. 1) Efficient, multidimensional and frequency resolved radiative transfer coupled to hydrodynamic needed 2) Codes must be able to simulate the observed light – ionisation as ...
Scientific Background Paper: Iron`s Place and Role
... producing an outward force to overcome the inward pull of gravity. The lifecycle of stars begins with the in-fall of a ball of gas and dust and their death is ultimately the failure to find a mechanism to arrest this in-fall. The details of the mechanisms used and the various stages of the evolution ...
... producing an outward force to overcome the inward pull of gravity. The lifecycle of stars begins with the in-fall of a ball of gas and dust and their death is ultimately the failure to find a mechanism to arrest this in-fall. The details of the mechanisms used and the various stages of the evolution ...
The effect of starspots on the radii of low-mass
... Fig. 1 compares the evolutionary tracks and radius as a function of time predicted by the BCAH98 model (for [M/H] = 0, Y = 0.275 and Lmix = HP ) with the results of the polytropic model for parameter values A = −132, B = 14 and n = 1.73 (corresponding to a = 0.35 and b = 16 in equation 2). The const ...
... Fig. 1 compares the evolutionary tracks and radius as a function of time predicted by the BCAH98 model (for [M/H] = 0, Y = 0.275 and Lmix = HP ) with the results of the polytropic model for parameter values A = −132, B = 14 and n = 1.73 (corresponding to a = 0.35 and b = 16 in equation 2). The const ...
Document
... The force between neutrons and protons (as well as within themselves) has a strong repulsive core At very high densities, this interaction provides an additional source of pressure. The shape of The potential when many particles are present is very difficult to calculate from first principles, and t ...
... The force between neutrons and protons (as well as within themselves) has a strong repulsive core At very high densities, this interaction provides an additional source of pressure. The shape of The potential when many particles are present is very difficult to calculate from first principles, and t ...
Diapositive 1
... • tracker lost 2006, but… • still working better than ever • 3” pixels, 1” pointing stability • follow object up to 8 weeks • time resolution ~sec-min • 3 modes: Fabry (V = 0…6), direct (V = 6…12), guide-star (<2006) • CCD + B/V filter ...
... • tracker lost 2006, but… • still working better than ever • 3” pixels, 1” pointing stability • follow object up to 8 weeks • time resolution ~sec-min • 3 modes: Fabry (V = 0…6), direct (V = 6…12), guide-star (<2006) • CCD + B/V filter ...
Ridgway - Betelgeuse Workshop 2016
... Unexpectedly large mass loss during the thermal pulse cycle of the red giant star R Sculptoris, M. Maercker, Elizabeth Humphreys et al., Nature 490, 232 (2012) ...
... Unexpectedly large mass loss during the thermal pulse cycle of the red giant star R Sculptoris, M. Maercker, Elizabeth Humphreys et al., Nature 490, 232 (2012) ...
Astronomy Astrophysics Carbon monoxide in the solar atmosphere &
... Aims. The role of carbon monoxide as a cooling agent for the thermal structure of the mid-photospheric to low-chromospheric layers of the solar atmosphere in internetwork regions is investigated. Methods. The treatment of radiative cooling via spectral lines of carbon monoxide (CO) has been added to ...
... Aims. The role of carbon monoxide as a cooling agent for the thermal structure of the mid-photospheric to low-chromospheric layers of the solar atmosphere in internetwork regions is investigated. Methods. The treatment of radiative cooling via spectral lines of carbon monoxide (CO) has been added to ...