FLARESTARSINTHEORIONN EBULAREGION SUMARIO Durante
... typical T Tauri stars in which, during long periods, the strong emission lines of H, CaII and some other bright lines, plus a rather strong ultraviolet continuum, are observed; b) nebular irregular variables with possible fainter emission lines and without conspicuous ultraviolet excesses during the ...
... typical T Tauri stars in which, during long periods, the strong emission lines of H, CaII and some other bright lines, plus a rather strong ultraviolet continuum, are observed; b) nebular irregular variables with possible fainter emission lines and without conspicuous ultraviolet excesses during the ...
The extended structure of the dwarf irregular galaxy Sagittarius⋆⋆⋆
... irregular galaxy Sagittarius (Sgr dIrr1 ). Sgr dIrr is a faint starforming galaxy (see Momany et al. 2005, hereafter M05) which is among the most gas-rich dwarfs in the local volume (Grcevich & Putman 2009). It is more distant than 1 Mpc from both the MW and M31. It was independently discovered by C ...
... irregular galaxy Sagittarius (Sgr dIrr1 ). Sgr dIrr is a faint starforming galaxy (see Momany et al. 2005, hereafter M05) which is among the most gas-rich dwarfs in the local volume (Grcevich & Putman 2009). It is more distant than 1 Mpc from both the MW and M31. It was independently discovered by C ...
Pre-main sequence evolution
... 1. Pre-main sequence evolution is driven by changes in temperature and density, which lead to changes in the dominant opacity contribution. => Stars alternate between convective and radiative phases. 2. The exact path of a PMS star in the Hertzsprung-Russel-Diagram, i.e. its luminosity-temperature e ...
... 1. Pre-main sequence evolution is driven by changes in temperature and density, which lead to changes in the dominant opacity contribution. => Stars alternate between convective and radiative phases. 2. The exact path of a PMS star in the Hertzsprung-Russel-Diagram, i.e. its luminosity-temperature e ...
Department of Physics and Astronomy University of
... Since the calculations in Ref. [Hel11] were done for 187 Os, we also adopt this isotope as our model ion. As part of a galactic chronometer that uses mass abundance ratios to evaluate the age of our galaxy, 187 Os is of special interest and is often discussed in the literature. However, as far as th ...
... Since the calculations in Ref. [Hel11] were done for 187 Os, we also adopt this isotope as our model ion. As part of a galactic chronometer that uses mass abundance ratios to evaluate the age of our galaxy, 187 Os is of special interest and is often discussed in the literature. However, as far as th ...
Dynamics of the Milky Way
... • Relaxation is expected to have occurred in some globular clusters and the densest nuclei of galaxies Dynamics of the Milky Way --- Part 1: Introduction and Fundamental Stellar Dynamics ...
... • Relaxation is expected to have occurred in some globular clusters and the densest nuclei of galaxies Dynamics of the Milky Way --- Part 1: Introduction and Fundamental Stellar Dynamics ...
grains of
... Observations are consistent with grain growth in disks, at least up to cmsized particles ...
... Observations are consistent with grain growth in disks, at least up to cmsized particles ...
Yellow supergiants as supernova progenitors: an indication of
... HRD of the progenitor. One of the most important physical process governing the evolution of massive stars is mass loss. Combined with rotation, it changes the evolution of the star radically (see the review by Maeder & Meynet 2011). However, the mass-loss rates inferred observationally or theoretic ...
... HRD of the progenitor. One of the most important physical process governing the evolution of massive stars is mass loss. Combined with rotation, it changes the evolution of the star radically (see the review by Maeder & Meynet 2011). However, the mass-loss rates inferred observationally or theoretic ...
The Stellar Initial Mass Function and Beyond
... cloud itself. It may be premature to claim that there is quantitative agreement between the clump mass spectrum and the stellar IMF, since a similar study of the ρ Oph clumps by Johnstone et al. (2000) finds somewhat larger clump masses and questions whether the smallest clumps found by Motte et al. ...
... cloud itself. It may be premature to claim that there is quantitative agreement between the clump mass spectrum and the stellar IMF, since a similar study of the ρ Oph clumps by Johnstone et al. (2000) finds somewhat larger clump masses and questions whether the smallest clumps found by Motte et al. ...
Teachers` guide
... Aim of this educational materials The supernova explosion is used as a method to measure the distance to far galaxies. Because the supernova explosion is very violent phenomenon, we can easily detect fairly far supernova’s appearance. Also, a part of supernova explosion which is called as Type Ia ha ...
... Aim of this educational materials The supernova explosion is used as a method to measure the distance to far galaxies. Because the supernova explosion is very violent phenomenon, we can easily detect fairly far supernova’s appearance. Also, a part of supernova explosion which is called as Type Ia ha ...
fundamental properties of kepler planet- candidate
... To detect oscillations and extract the global oscillation parameters Δν and νmax , we have used the analysis pipelines described by Huber et al. (2009), Hekker et al. (2010), Karoff et al. (2010), Verner & Roxburgh (2011) and Lund et al. (2012). Note that these methods have been extensively tested o ...
... To detect oscillations and extract the global oscillation parameters Δν and νmax , we have used the analysis pipelines described by Huber et al. (2009), Hekker et al. (2010), Karoff et al. (2010), Verner & Roxburgh (2011) and Lund et al. (2012). Note that these methods have been extensively tested o ...
evolución química de la nube grande de magallanes.
... dwarf spheroidal (dSph) and dwarf irregular (dIrr) galaxies very good candidates to be building blocks of our Galaxy. Taking this last scenario into account, plus the intriguing star cluster population and what little is known of the chemical evolution of our galaxy neighbour, the Large Magellanic C ...
... dwarf spheroidal (dSph) and dwarf irregular (dIrr) galaxies very good candidates to be building blocks of our Galaxy. Taking this last scenario into account, plus the intriguing star cluster population and what little is known of the chemical evolution of our galaxy neighbour, the Large Magellanic C ...
I Introduction to the Interstellar Medium
... The first observational evidence that there was a general ISM that pervaded the space between the stars came from photographic spectroscopy of spectroscopic binary stars early in the 20th century. It was noticed that in addition to the relatively broad absorption lines associated with the atmosphere ...
... The first observational evidence that there was a general ISM that pervaded the space between the stars came from photographic spectroscopy of spectroscopic binary stars early in the 20th century. It was noticed that in addition to the relatively broad absorption lines associated with the atmosphere ...
Neutron stars as probes of extreme energy density matter
... DOI: 10.1007/s12043-015-0979-7; ePublication: 7 May 2015 Abstract. Neutron stars have long been regarded as extraterrestrial laboratories from which we can learn about extreme energy density matter at low temperatures. In this article, some of the recent advances made in astrophysical observations a ...
... DOI: 10.1007/s12043-015-0979-7; ePublication: 7 May 2015 Abstract. Neutron stars have long been regarded as extraterrestrial laboratories from which we can learn about extreme energy density matter at low temperatures. In this article, some of the recent advances made in astrophysical observations a ...
Transport of angular momentum in massive stars
... 2010). The listed observed stars with their absolute brightness and color, and created the Hertzsprung-Russell diagram that has been used by astronomers ever since. The Hertzsprung-Russell diagram is mostly used to understand the evolution of stars. Today we know the distance to many star clusters. ...
... 2010). The listed observed stars with their absolute brightness and color, and created the Hertzsprung-Russell diagram that has been used by astronomers ever since. The Hertzsprung-Russell diagram is mostly used to understand the evolution of stars. Today we know the distance to many star clusters. ...
Properties of Galactic B supergiants
... line forming region. We find that the so-called ‘bistability jump’ at B1 (Teff ∼ 21kK) from Lamers et al. is rather a more gradual downward trend. CNO elemental abundances, including Sher 25, reveal partially processed material at their surfaces. In general, these are in good agreement with evolutio ...
... line forming region. We find that the so-called ‘bistability jump’ at B1 (Teff ∼ 21kK) from Lamers et al. is rather a more gradual downward trend. CNO elemental abundances, including Sher 25, reveal partially processed material at their surfaces. In general, these are in good agreement with evolutio ...
Population synthesis for double white dwarfs-II. Semi
... line, with ζ(m) derived from Eq. (5). The initial masstransfer rates, as given by Eq. (3), can be higher than the Eddington limit of the accretor (Tutukov & Yungelson 1979). The matter that cannot be accreted is lost from the system, taking along some angular momentum. The binary system may remain s ...
... line, with ζ(m) derived from Eq. (5). The initial masstransfer rates, as given by Eq. (3), can be higher than the Eddington limit of the accretor (Tutukov & Yungelson 1979). The matter that cannot be accreted is lost from the system, taking along some angular momentum. The binary system may remain s ...
Doppler imaging of AB Doradus using the Li I 6708 line
... spread remains a puzzle. Recent theoretical attempts to explain it have focused on the observed tendency of the fastest rotators at any given spectral type to have the greatest abundances of Li (Butler et al. 1987). While this might indicate that rotation in some way inhibits mixing of Li-rich mater ...
... spread remains a puzzle. Recent theoretical attempts to explain it have focused on the observed tendency of the fastest rotators at any given spectral type to have the greatest abundances of Li (Butler et al. 1987). While this might indicate that rotation in some way inhibits mixing of Li-rich mater ...
6. Stellar Spectra
... Are the ionization levels for different elements observed in a given spectral type consistent with a ...
... Are the ionization levels for different elements observed in a given spectral type consistent with a ...
MIXED CHEMISTRY
... http://azstarnet.com/news/science/article_57d08830-a127-5bbb-b57ef4262017e887.html ...
... http://azstarnet.com/news/science/article_57d08830-a127-5bbb-b57ef4262017e887.html ...
The chemical case for no winds in dwarf irregular galaxies
... In this work, we focus our attention on the evolution of isolated gas-rich dwarf galaxies, not affected by external environmental processes. One of the agents that may regulate the star formation history of these objects is the presence of strong galactic winds. If they have a low mass and a high st ...
... In this work, we focus our attention on the evolution of isolated gas-rich dwarf galaxies, not affected by external environmental processes. One of the agents that may regulate the star formation history of these objects is the presence of strong galactic winds. If they have a low mass and a high st ...
Extreme abundance ratios in the polluted atmosphere of the cool
... catalogue did not contain any flags that would suggest problems with the JHK photometry. ...
... catalogue did not contain any flags that would suggest problems with the JHK photometry. ...
MHD seismology as a tool to diagnose the coronae of X
... these Sun-like stars have seed magnetic field generation in their interior, which transport outward to permeate their chromosphere and coronae in leading to the formation of transients (e.g., flares) as well as some form of MHD wave activity (e.g., Pandey & Srivastava 2009) similar to the transients ...
... these Sun-like stars have seed magnetic field generation in their interior, which transport outward to permeate their chromosphere and coronae in leading to the formation of transients (e.g., flares) as well as some form of MHD wave activity (e.g., Pandey & Srivastava 2009) similar to the transients ...
Correlation Between Nitrogen and Oxygen Content in Planetary
... that the data from this experiment is representative of a large group. However, some trends and patterns are evident within this data. When looking only at the percent (light) composition data for oxygen and nitrogen, especially when a trend line is added to the data points, a split can be seen betw ...
... that the data from this experiment is representative of a large group. However, some trends and patterns are evident within this data. When looking only at the percent (light) composition data for oxygen and nitrogen, especially when a trend line is added to the data points, a split can be seen betw ...
full text pdf
... dominant theories talk about "channels" for white dwarf formation, with the most discussed channels being "born DA" white dwarfs resulting from hydrogen-rich planetary nebula nuclei (PNN) and white dwarfs resulting from the H e / C / O PNN that become P G 1159 stars before becoming white dwarfs. Fon ...
... dominant theories talk about "channels" for white dwarf formation, with the most discussed channels being "born DA" white dwarfs resulting from hydrogen-rich planetary nebula nuclei (PNN) and white dwarfs resulting from the H e / C / O PNN that become P G 1159 stars before becoming white dwarfs. Fon ...
ppt
... • Gunn-Peterson absorption trough is found – reionization time scales can be deduced. • Combine with other studies, this discovery is also a strong evidence for the important role of supermassive black hole (106 – 109 solar) in galaxy evolution. ...
... • Gunn-Peterson absorption trough is found – reionization time scales can be deduced. • Combine with other studies, this discovery is also a strong evidence for the important role of supermassive black hole (106 – 109 solar) in galaxy evolution. ...
Nucleosynthesis
Nucleosynthesis is the process that creates new atomic nuclei from pre-existing nucleons, primarily protons and neutrons. The first nuclei were formed about three minutes after the Big Bang, through the process called Big Bang nucleosynthesis. It was then that hydrogen and helium formed to become the content of the first stars, and this primeval process is responsible for the present hydrogen/helium ratio of the cosmos.With the formation of stars, heavier nuclei were created from hydrogen and helium by stellar nucleosynthesis, a process that continues today. Some of these elements, particularly those lighter than iron, continue to be delivered to the interstellar medium when low mass stars eject their outer envelope before they collapse to form white dwarfs. The remains of their ejected mass form the planetary nebulae observable throughout our galaxy.Supernova nucleosynthesis within exploding stars by fusing carbon and oxygen is responsible for the abundances of elements between magnesium (atomic number 12) and nickel (atomic number 28). Supernova nucleosynthesis is also thought to be responsible for the creation of rarer elements heavier than iron and nickel, in the last few seconds of a type II supernova event. The synthesis of these heavier elements absorbs energy (endothermic) as they are created, from the energy produced during the supernova explosion. Some of those elements are created from the absorption of multiple neutrons (the R process) in the period of a few seconds during the explosion. The elements formed in supernovas include the heaviest elements known, such as the long-lived elements uranium and thorium.Cosmic ray spallation, caused when cosmic rays impact the interstellar medium and fragment larger atomic species, is a significant source of the lighter nuclei, particularly 3He, 9Be and 10,11B, that are not created by stellar nucleosynthesis.In addition to the fusion processes responsible for the growing abundances of elements in the universe, a few minor natural processes continue to produce very small numbers of new nuclides on Earth. These nuclides contribute little to their abundances, but may account for the presence of specific new nuclei. These nuclides are produced via radiogenesis (decay) of long-lived, heavy, primordial radionuclides such as uranium and thorium. Cosmic ray bombardment of elements on Earth also contribute to the presence of rare, short-lived atomic species called cosmogenic nuclides.