Hot Horizontal Branch Stars in the Galactic Bulge. I
... D’Cruz et al. 1996). It may also be accomplished with deep mixing, and thus accompanied by light-element enhancements (Sweigart 1997; Kraft et al. 1998). However, binary mass transfer may play a dominant role at the hot end of the BHB, since a large fraction of field sdB/O stars are found to be bina ...
... D’Cruz et al. 1996). It may also be accomplished with deep mixing, and thus accompanied by light-element enhancements (Sweigart 1997; Kraft et al. 1998). However, binary mass transfer may play a dominant role at the hot end of the BHB, since a large fraction of field sdB/O stars are found to be bina ...
The Evolution of Isotope Ratios in the Milky Way Galaxy
... Stellar winds reduce the stellar mass to Mfinal at the onset of the supernova explosion, with the central mass Mcut falling onto the remnant. The stellar winds with the mass of Minitial − Mfinal contains unprocessed metals, which are not included in the tables but are included in the chemical evo3 ...
... Stellar winds reduce the stellar mass to Mfinal at the onset of the supernova explosion, with the central mass Mcut falling onto the remnant. The stellar winds with the mass of Minitial − Mfinal contains unprocessed metals, which are not included in the tables but are included in the chemical evo3 ...
Sparse aperture masking at the VLT II. Detection limits for the eight
... a debris disk, a proto-planetary disk or a planetary system. The understanding of such formation process requires the study of debris disks. These targets are substantial and particularly suitable for optical and infrared observations. Sparse Aperture masking (SAM) is a high angular resolution techn ...
... a debris disk, a proto-planetary disk or a planetary system. The understanding of such formation process requires the study of debris disks. These targets are substantial and particularly suitable for optical and infrared observations. Sparse Aperture masking (SAM) is a high angular resolution techn ...
Cycles of magnetic activity in solar-type stars. The place of the Sun
... these 50 stars with cycles they have found only 12 stars and the Sun to be characterized by the cyclic activity of the "Excellent" class. We illustrate the method of cyclic period calculation with Scargle’s periodogram technique on the example of the Sun. We obtained the periodogram of the yearly av ...
... these 50 stars with cycles they have found only 12 stars and the Sun to be characterized by the cyclic activity of the "Excellent" class. We illustrate the method of cyclic period calculation with Scargle’s periodogram technique on the example of the Sun. We obtained the periodogram of the yearly av ...
Deep SDSS optical spectroscopy of distant halo stars I. Atmospheric
... Fig. 1. Sample BOSS spectra (black) for two representative low-metallicity F-type stars, a dwarf and a giant. The spectra are divided into 20 equal-velocity bins and normalized by their mean value in each bin, as described in the text. The best-fitting parameters and models (red curves) are shown. T ...
... Fig. 1. Sample BOSS spectra (black) for two representative low-metallicity F-type stars, a dwarf and a giant. The spectra are divided into 20 equal-velocity bins and normalized by their mean value in each bin, as described in the text. The best-fitting parameters and models (red curves) are shown. T ...
Astronomy Astrophysics Detailed abundances of a large sample of giant stars in... and in the Sagittarius nucleus
... comprehensive reviews): their stars do not satisfy the very definition of a simple stellar population (SSP). In contrast, all the evidence suggests that GCs had a significant and very peculiar chemical evolution including self-enrichment of metals from ejecta of massive stars early in their lifetime ...
... comprehensive reviews): their stars do not satisfy the very definition of a simple stellar population (SSP). In contrast, all the evidence suggests that GCs had a significant and very peculiar chemical evolution including self-enrichment of metals from ejecta of massive stars early in their lifetime ...
Presolar Cloud Collapse and the Formation and Early Evolution of
... 2.2.2. Shock-triggered collapse and injection of radioactivity. This standard model has been challenged by evidence for short cloud lifetimes and a highly dynamic starformation process driven by large-scale outflows (Hartmann et al., 2001). A case for a short lifetime of the protosolar cloud has als ...
... 2.2.2. Shock-triggered collapse and injection of radioactivity. This standard model has been challenged by evidence for short cloud lifetimes and a highly dynamic starformation process driven by large-scale outflows (Hartmann et al., 2001). A case for a short lifetime of the protosolar cloud has als ...
Extrasolar Kuiper Belt Dust Disks
... by evaporation of comets scattered close to the star (Backman and Paresce, 1993). At any particular age, observations show a great diversity of debris disks surrounding similar type stars [see section 3.1 and Andrews and Williams (2005)]. This may be due to the following factors that can influence t ...
... by evaporation of comets scattered close to the star (Backman and Paresce, 1993). At any particular age, observations show a great diversity of debris disks surrounding similar type stars [see section 3.1 and Andrews and Williams (2005)]. This may be due to the following factors that can influence t ...
WAS THE SUN BORN IN A MASSIVE CLUSTER?
... A number of authors have argued that the Sun must have been born in a cluster of no more than several thousand stars, on the basis that, in a larger cluster, close encounters between the Sun and other stars would have truncated the outer solar system or excited the outer planets into eccentric orbit ...
... A number of authors have argued that the Sun must have been born in a cluster of no more than several thousand stars, on the basis that, in a larger cluster, close encounters between the Sun and other stars would have truncated the outer solar system or excited the outer planets into eccentric orbit ...
Rotation Periods of Wide Binaries in the Kepler Field
... Because most of the stars that satisfy the present criteria are relatively nearby, they should be expected to have low interstellar reddening. In any case, since the two components presumably lie at the same distance, the reddening would be expected to be the same, and so will not affect Figure 1. T ...
... Because most of the stars that satisfy the present criteria are relatively nearby, they should be expected to have low interstellar reddening. In any case, since the two components presumably lie at the same distance, the reddening would be expected to be the same, and so will not affect Figure 1. T ...
A Search for Extrasolar Planets Using Echoes Produced in Flare
... The two-ribbon flare begins with a filament, essentially a mass of cool charged particles producing a line current suspended in a magnetic field “tube” extending through the stellar atmosphere (Haisch et. al., 1991; Martens and Kuin, 1989). The connection points of the line current with the photosph ...
... The two-ribbon flare begins with a filament, essentially a mass of cool charged particles producing a line current suspended in a magnetic field “tube” extending through the stellar atmosphere (Haisch et. al., 1991; Martens and Kuin, 1989). The connection points of the line current with the photosph ...
CHAPTER 1 The Formation and Structure of Stars
... – Temperature is a measure of the motion of the atoms or molecules in a material—in a hot gas, the atoms move more rapidly than do those in a cool gas. – Although the interstellar clouds are very cold, even at a temperature of only 10 K, the average hydrogen atom moves about 0.5 km/s (1,100 mph). – ...
... – Temperature is a measure of the motion of the atoms or molecules in a material—in a hot gas, the atoms move more rapidly than do those in a cool gas. – Although the interstellar clouds are very cold, even at a temperature of only 10 K, the average hydrogen atom moves about 0.5 km/s (1,100 mph). – ...
Chap2-RadialVelocity
... mass) defined as where M and a refers to the mass and semi-major axis, respectively. (Notation: subscript p for planet and ★ for the host star; arel is used for a planet orbit relative to the star) Reflex motion results in periodic perturbation of: radial velocity, angular position on the sky, and ...
... mass) defined as where M and a refers to the mass and semi-major axis, respectively. (Notation: subscript p for planet and ★ for the host star; arel is used for a planet orbit relative to the star) Reflex motion results in periodic perturbation of: radial velocity, angular position on the sky, and ...
Rotation, activity, and stellar obliquities in a large uniform sample of
... the vast majority (Fressin et al. 2013; Coughlin et al. 2014) of the KOIs are expected to turn out to be true planet hosts rather than false positives, and for the purposes of this study we treated this sample as if all were truly exoplanet host stars. The non-KOI sample, of course, is expected to c ...
... the vast majority (Fressin et al. 2013; Coughlin et al. 2014) of the KOIs are expected to turn out to be true planet hosts rather than false positives, and for the purposes of this study we treated this sample as if all were truly exoplanet host stars. The non-KOI sample, of course, is expected to c ...
Abstracts - Physics of Evolved Stars 2015
... OH/IR stars are believed to be the final stage on the asymptotic giant branch (AGB) of intermediate main-sequence mass (5-8 solar masses) stars before they evolve into the post-AGB and planetary-nebula stages. AGB stars lose most of their stellar envelope in the form of a gaseous and dusty stellar w ...
... OH/IR stars are believed to be the final stage on the asymptotic giant branch (AGB) of intermediate main-sequence mass (5-8 solar masses) stars before they evolve into the post-AGB and planetary-nebula stages. AGB stars lose most of their stellar envelope in the form of a gaseous and dusty stellar w ...
Hot subdwarf stars-galactic orbits and distribution perpendicular to
... Hot subdwarfs are blue, horizontal-branch like stars, representing the late stages of evolution of stars having started with less than about 2.5 M⊙ on the main sequence. The hotter subdwarf B (sdB) stars form a well defined group. Their luminosity is of the order of 10 L⊙ and their surface temperatu ...
... Hot subdwarfs are blue, horizontal-branch like stars, representing the late stages of evolution of stars having started with less than about 2.5 M⊙ on the main sequence. The hotter subdwarf B (sdB) stars form a well defined group. Their luminosity is of the order of 10 L⊙ and their surface temperatu ...
Properties of Wolf-Rayet Stars - Paul Crowther, University of Sheffield
... Visual spectral classification of WR stars is based on emission line strengths and line ratios (Smith 1968). To date, high-ionization WN2 to WN5 are known as ‘early WN’ (WNE) stars, and low-ionization WN7 to WN9(–11) stars known as ‘late WN’ (WNL) stars, and WN6 stars either early or late-type. Comp ...
... Visual spectral classification of WR stars is based on emission line strengths and line ratios (Smith 1968). To date, high-ionization WN2 to WN5 are known as ‘early WN’ (WNE) stars, and low-ionization WN7 to WN9(–11) stars known as ‘late WN’ (WNL) stars, and WN6 stars either early or late-type. Comp ...
- StealthSkater
... planets. Apparently the formation of a planetary system robs the star of much of its rotational momentum. For two reasons, then, we eliminate stars of class 'F4' and above: (1) most of them rotate rapidly and thus seem to be planet-less; and (2) their stable lifespans are too brief for advanced life ...
... planets. Apparently the formation of a planetary system robs the star of much of its rotational momentum. For two reasons, then, we eliminate stars of class 'F4' and above: (1) most of them rotate rapidly and thus seem to be planet-less; and (2) their stable lifespans are too brief for advanced life ...
Debris Disks: Seeing Dust, Thinking of Planetesimals and Planets
... An inventory of our own planetary system uncovers its complex architecture. Eight known planets are arranged in two groups, four terrestrial ones and four giants. The main asteroid belt between two groups of planets, terrestrial and giant ones, comprises planetesimals that failed to grow to planets ...
... An inventory of our own planetary system uncovers its complex architecture. Eight known planets are arranged in two groups, four terrestrial ones and four giants. The main asteroid belt between two groups of planets, terrestrial and giant ones, comprises planetesimals that failed to grow to planets ...
Do We Know of Any Maunder Minimum Stars?
... There is a degeneracy between the effects of metallicity and evolution in a star’s position on a color-magnitude diagram: both evolution and enhanced metallicity place stars to the right of the main sequence. Based upon the theoretical isochrones of Girardi et al. (2002), I estimate that a star with ...
... There is a degeneracy between the effects of metallicity and evolution in a star’s position on a color-magnitude diagram: both evolution and enhanced metallicity place stars to the right of the main sequence. Based upon the theoretical isochrones of Girardi et al. (2002), I estimate that a star with ...
MPhil Thesis - Final - Suzanne Knight
... host stars evolve off the main sequence. An effective method in finding indirect evidence for the presence of planets is to search for remnants of planetary systems around these post-main sequence stars. Theoretical studies have shown that a fraction of planets can survive the red giant stage of the ...
... host stars evolve off the main sequence. An effective method in finding indirect evidence for the presence of planets is to search for remnants of planetary systems around these post-main sequence stars. Theoretical studies have shown that a fraction of planets can survive the red giant stage of the ...
Grade 9 Space Review 50KB Nov 18 2009 10:52:00 AM
... When these large stars became supernova, they expelled most of the elements they manufactured as gas and dust. The gas and dust eventually helped to form our Sun. PTS: 1 REF: AS STA: UBC7 39. ANS: A planetary nebula is thought to be a small part of the matter from a dying red giant star ejected to f ...
... When these large stars became supernova, they expelled most of the elements they manufactured as gas and dust. The gas and dust eventually helped to form our Sun. PTS: 1 REF: AS STA: UBC7 39. ANS: A planetary nebula is thought to be a small part of the matter from a dying red giant star ejected to f ...
Formation of the Solar System
... orbit around their common center of mass. • The Sun therefore wobbles around that center of mass with the same period as Jupiter. © 2007 Pearson Education Inc., publishing as Pearson Addison-Wesley ...
... orbit around their common center of mass. • The Sun therefore wobbles around that center of mass with the same period as Jupiter. © 2007 Pearson Education Inc., publishing as Pearson Addison-Wesley ...
Unit 1 test review and answer key 16
... Ptolemy’s theory of planets moving within wheels attached to circular spheres centred on Earth was very complex and difficult to use. ...
... Ptolemy’s theory of planets moving within wheels attached to circular spheres centred on Earth was very complex and difficult to use. ...
Planetary system
A planetary system is a set of gravitationally bound non-stellar objects in orbit around a star or star system. Generally speaking, systems with one or more planets constitute a planetary system, although such systems may also consist of bodies such as dwarf planets, asteroids, natural satellites, meteoroids, comets, planetesimals and circumstellar disks. The Sun together with its planetary system, which includes Earth, is known as the Solar System. The term exoplanetary system is sometimes used in reference to other planetary systems.A total of 1968 exoplanets (in 1248 planetary systems, including 490 multiple planetary systems) have been identified as of 1 October 2015.Of particular interest to astrobiology is the habitable zone of planetary systems where planets could have surface liquid water.