Article PDF - IOPscience
... (60 × 2 kpc) Hα emitting region associated with a galaxy of the Coma cluster. Sun et al. (2007) found a ∼40 kpc Hα tail of a galaxy in Abell 3627. The galaxy also had a ∼70 kpc X-ray tail. Sun et al. (2010) investigated the galaxy to show two ∼80 kpc tails, and also reported one more galaxy with a > ...
... (60 × 2 kpc) Hα emitting region associated with a galaxy of the Coma cluster. Sun et al. (2007) found a ∼40 kpc Hα tail of a galaxy in Abell 3627. The galaxy also had a ∼70 kpc X-ray tail. Sun et al. (2010) investigated the galaxy to show two ∼80 kpc tails, and also reported one more galaxy with a > ...
Variable Stars – II. Pulsating stars
... • Radial pulsations are a special subset (with ℓ = 0) of the more general non-radial pulsations or non-radial pressure modes (often written p-modes) – for which the restoring force is pressure. • Non-radial pulsators can also pulsate in gravity modes or g-modes, where gravity – actually buoyancy – i ...
... • Radial pulsations are a special subset (with ℓ = 0) of the more general non-radial pulsations or non-radial pressure modes (often written p-modes) – for which the restoring force is pressure. • Non-radial pulsators can also pulsate in gravity modes or g-modes, where gravity – actually buoyancy – i ...
D ASTROPHYSICS
... A galaxy is a creation of stars, gas, and dust held together by gravity and containing billions of stars. The Milky Way contains about 3 × 10 11 stars and, probably, at least this number of planets. Some galaxies exist in isolation but the majority of them occur in groups known as clusters that have ...
... A galaxy is a creation of stars, gas, and dust held together by gravity and containing billions of stars. The Milky Way contains about 3 × 10 11 stars and, probably, at least this number of planets. Some galaxies exist in isolation but the majority of them occur in groups known as clusters that have ...
Star-Galaxy Classification in Multi
... the data set, they generally show improved probabilistic performance over simpler approaches, while requiring no additional knowledge outside the observed data and the template SEDs. Functionally, hierarchical approaches consist of parameterizing the prior probability distributions (for example, wit ...
... the data set, they generally show improved probabilistic performance over simpler approaches, while requiring no additional knowledge outside the observed data and the template SEDs. Functionally, hierarchical approaches consist of parameterizing the prior probability distributions (for example, wit ...
star pattern identification : application to the precise attitude
... The Auroral Spacecraft is one of the four satellites launched for the Interball project by the Russian Space Agency in cooperation with the international scientific community which are dedicated to magnetospheric research. This spacecraft is subject to the effects of energy exchange between the flex ...
... The Auroral Spacecraft is one of the four satellites launched for the Interball project by the Russian Space Agency in cooperation with the international scientific community which are dedicated to magnetospheric research. This spacecraft is subject to the effects of energy exchange between the flex ...
Estudio de Cúmulos de Galaxias en el Sloan Digital Sky Survey
... Baugh et al. 2005: - Reproduce the z=3 LF of LBGs - Reproduce the number of SMGs. ...
... Baugh et al. 2005: - Reproduce the z=3 LF of LBGs - Reproduce the number of SMGs. ...
Astronomy 112: The Physics of Stars Class 16 Notes: Post
... time. Once it violates the Schönberg-Chandresekhar limit, and it becomes powered by gravitational contraction, it heats up even more. Thus the core is always getting hotter during the red giant phase. What happens next depends on the mass of the star. A. Stars 1.8 − 10 M First consider fairly mas ...
... time. Once it violates the Schönberg-Chandresekhar limit, and it becomes powered by gravitational contraction, it heats up even more. Thus the core is always getting hotter during the red giant phase. What happens next depends on the mass of the star. A. Stars 1.8 − 10 M First consider fairly mas ...
... the Orion trapezium). These considerations suggest the possibility that a given trapezium may eject several low-mass stars throughout its lifetime. Scarfe – Are there stars near some of your groups that have not been included in your discussion? If so, there may be some observational selection in yo ...
On the nature and detectability of Type Ib/c supernova progenitors
... Galactic WR stars have masses higher than about 8 M⊙ and many of them are thought to have originated from massive single stars through stellar-wind mass-loss. In binary systems, lowermass helium stars can be produced via mass transfer. As discussed by Yoon et al. (2010), such relatively low-mass hel ...
... Galactic WR stars have masses higher than about 8 M⊙ and many of them are thought to have originated from massive single stars through stellar-wind mass-loss. In binary systems, lowermass helium stars can be produced via mass transfer. As discussed by Yoon et al. (2010), such relatively low-mass hel ...
Topic 2 Chemical Composition of Stars
... • Point in the star’s evolution − for example, some advanced stars can lose the “envelope” of gas around them (we will look more closely at this later in the course) • Mixing of surface layers • Certain stars are Chemically Peculiar (CP) and exhibit dramatic over/ under abundances of elements whi ...
... • Point in the star’s evolution − for example, some advanced stars can lose the “envelope” of gas around them (we will look more closely at this later in the course) • Mixing of surface layers • Certain stars are Chemically Peculiar (CP) and exhibit dramatic over/ under abundances of elements whi ...
arXiv:astro-ph/9909369 v1 22 Sep 1999
... decreases outwards, this implies that the scale-length of the cold dust column density is even larger. Comparison of radial profiles between cold dust traced at 850 µm with SCUBA and the atomic and molecular components show that while the cold dust is more extended than the molecular gas, it is stil ...
... decreases outwards, this implies that the scale-length of the cold dust column density is even larger. Comparison of radial profiles between cold dust traced at 850 µm with SCUBA and the atomic and molecular components show that while the cold dust is more extended than the molecular gas, it is stil ...
$^{13} $ CO/C $^{18} $ O Gradients Across the Disks of Nearby
... the largest radius where we can still achieve a detection, typically 13 CO/C18 O ∼16 at ∼ 0.4×r25 . At this radius, the ISM transitions from H2 to H I dominate (see Schruba et al. 2011). To our knowledge, such high ratios have not been reported before for normal star-forming disk galaxies. Using ALM ...
... the largest radius where we can still achieve a detection, typically 13 CO/C18 O ∼16 at ∼ 0.4×r25 . At this radius, the ISM transitions from H2 to H I dominate (see Schruba et al. 2011). To our knowledge, such high ratios have not been reported before for normal star-forming disk galaxies. Using ALM ...
chapter17StarStuff
... • High-mass stars with >8MSun have short lives, eventually becoming hot enough to make iron, and end in supernova explosions • Low-mass stars with <2MSun have long lives, never become hot enough to fuse carbon nuclei, and end as white dwarfs • Intermediate mass stars can make elements heavier than c ...
... • High-mass stars with >8MSun have short lives, eventually becoming hot enough to make iron, and end in supernova explosions • Low-mass stars with <2MSun have long lives, never become hot enough to fuse carbon nuclei, and end as white dwarfs • Intermediate mass stars can make elements heavier than c ...
Publications 2003 - Département d`Astrophysique, Géophysique et
... as the results of the analysis of the obtained time series are presented, the main conclusion being that nine stars are thought to be multiperiodic gamma Dor stars and eight monoperiodic. We also performed a photometric mode identification for two stars of the sample by comparing the amplitude ratio ...
... as the results of the analysis of the obtained time series are presented, the main conclusion being that nine stars are thought to be multiperiodic gamma Dor stars and eight monoperiodic. We also performed a photometric mode identification for two stars of the sample by comparing the amplitude ratio ...
Cloud Formation, Evolution and Destruction
... stored as magnetic energy, to be re-released back into the turbulent motions. Computer simulations finally laid serious doubt, not on the existence of such waves, but on their durability. At the same time our knowledge of clouds and the distributions of young stars had been accumulating. The hard re ...
... stored as magnetic energy, to be re-released back into the turbulent motions. Computer simulations finally laid serious doubt, not on the existence of such waves, but on their durability. At the same time our knowledge of clouds and the distributions of young stars had been accumulating. The hard re ...
MS PowerPoint - National Schools` Observatory
... If there were no external factors at play, the absorption spectrum of a star would show very thin spectral line features at the exact wavelengths corresponding to amount of energy transferred to the atom when one of its electrons has been excited to a higher energy level. ...
... If there were no external factors at play, the absorption spectrum of a star would show very thin spectral line features at the exact wavelengths corresponding to amount of energy transferred to the atom when one of its electrons has been excited to a higher energy level. ...
PoS(EVN 2014)058 - Proceeding of science
... The greatest barrier to understanding massive stars is the nature and magnitude of their massloss, which has profound implications for many areas of astrophysics including stellar evolution. Recent results have strongly challenged the current models and it is now recognised that there is significant ...
... The greatest barrier to understanding massive stars is the nature and magnitude of their massloss, which has profound implications for many areas of astrophysics including stellar evolution. Recent results have strongly challenged the current models and it is now recognised that there is significant ...
1 Introduction - High Point University
... 3. Check show luminosity classes and show isoradius lines (if they are not already checked). The green region (Dwarfs (V)) is known as the main sequence and contains all stars that are fusing hydrogen into helium as their primary energy source. Over 90% of all stars fall in this region on the H-R di ...
... 3. Check show luminosity classes and show isoradius lines (if they are not already checked). The green region (Dwarfs (V)) is known as the main sequence and contains all stars that are fusing hydrogen into helium as their primary energy source. Over 90% of all stars fall in this region on the H-R di ...
Chapter 31
... wavelengths than they do in wavelengths of visible light. • The radio emission usually comes from two huge lobes of very hot gas located on opposite sides of the visible galaxy, linked by jets of gas. • Active galactic nuclei, or AGNs, in some unusual galaxies, contain a highly energetic object or a ...
... wavelengths than they do in wavelengths of visible light. • The radio emission usually comes from two huge lobes of very hot gas located on opposite sides of the visible galaxy, linked by jets of gas. • Active galactic nuclei, or AGNs, in some unusual galaxies, contain a highly energetic object or a ...
2. The Anatomy of Stellar Life and Death
... and Peter Schilke (University of Cologne) of a star-forming region IRAS 19410–2336 revealed that the process of massive stars formation appeared to mirror that of lower mass star formation with a very similar scaling of the mass of protostars. The observations were done in the millimeter (microwave) ...
... and Peter Schilke (University of Cologne) of a star-forming region IRAS 19410–2336 revealed that the process of massive stars formation appeared to mirror that of lower mass star formation with a very similar scaling of the mass of protostars. The observations were done in the millimeter (microwave) ...
Lecture Topics 1023
... ASTR 1023 Lecture Topics These are the headings of the paragraphs into which ASTR 1023 lectures are divided. Use them to check your notes for completeness, and to see how the course is organized. It is also a good idea to cross-check these topics with your reading assignments, because some topics ar ...
... ASTR 1023 Lecture Topics These are the headings of the paragraphs into which ASTR 1023 lectures are divided. Use them to check your notes for completeness, and to see how the course is organized. It is also a good idea to cross-check these topics with your reading assignments, because some topics ar ...
Camelopardalis-Better-Know-A-Constellation
... Can be seen in binoculars from country skies, sometimes fools comet hunters. NGC 2403 possesses about 100 emission regions as well as 27 variable stars. Larger instruments will reveal many of these regions that seem to take on likeliness to M33. Three supernovae have been spotted in this galaxy, one ...
... Can be seen in binoculars from country skies, sometimes fools comet hunters. NGC 2403 possesses about 100 emission regions as well as 27 variable stars. Larger instruments will reveal many of these regions that seem to take on likeliness to M33. Three supernovae have been spotted in this galaxy, one ...
determining stellar parameters from star`s
... The most fundamental properties of a star are its mass, age and chemical composition. Unfortunately, age is not directly observable and masses can only be determined directly (i.e. dynamically) in select binary systems. Nonetheless, important parameters, in particular the effective temperature, surf ...
... The most fundamental properties of a star are its mass, age and chemical composition. Unfortunately, age is not directly observable and masses can only be determined directly (i.e. dynamically) in select binary systems. Nonetheless, important parameters, in particular the effective temperature, surf ...
Age Estimates of Globular Clusters in the Milky Way
... ages of individual stars using the known radioactive half-lives of these elements (232Th has a half-life of 14 billion years, whereas 238U has a half-life of 4.5 billion years), if one can estimate the initial abundance ratio of these two elements. There are two principal difficulties with radioacti ...
... ages of individual stars using the known radioactive half-lives of these elements (232Th has a half-life of 14 billion years, whereas 238U has a half-life of 4.5 billion years), if one can estimate the initial abundance ratio of these two elements. There are two principal difficulties with radioacti ...
H II region
An H II region is a large, low-density cloud of partially ionized gas in which star formation has recently taken place. The short-lived blue stars forged in these regions emit copious amounts of ultraviolet light that ionize the surrounding gas. H II regions—sometimes several hundred light-years across—are often associated with giant molecular clouds. The first known H II region was the Orion Nebula, which was discovered in 1610 by Nicolas-Claude Fabri de Peiresc.H II regions are named for the large amount of ionised atomic hydrogen they contain, referred to as H II, pronounced H-two by astronomers (an H I region being neutral atomic hydrogen, and H2 being molecular hydrogen). Such regions have extremely diverse shapes, because the distribution of the stars and gas inside them is irregular. They often appear clumpy and filamentary, sometimes showing bizarre shapes such as the Horsehead Nebula. H II regions may give birth to thousands of stars over a period of several million years. In the end, supernova explosions and strong stellar winds from the most massive stars in the resulting star cluster will disperse the gases of the H II region, leaving behind a cluster of birthed stars such as the Pleiades.H II regions can be seen to considerable distances in the universe, and the study of extragalactic H II regions is important in determining the distance and chemical composition of other galaxies. Spiral and irregular galaxies contain many H II regions, while elliptical galaxies are almost devoid of them. In the spiral galaxies, including the Milky Way, H II regions are concentrated in the spiral arms, while in the irregular galaxies they are distributed chaotically. Some galaxies contain huge H II regions, which may contain tens of thousands of stars. Examples include the 30 Doradus region in the Large Magellanic Cloud and NGC 604 in the Triangulum Galaxy.