11-Massive Stars
... Therefore, they are often easy to resolve spatially despite their typical distance of kiloparsecs. The major question is: are these bipolar outflows driven by the same mechanism as those from low-mass stars? For example, the magnetocentrifugal wind scenarios predicts outflows which are morphological ...
... Therefore, they are often easy to resolve spatially despite their typical distance of kiloparsecs. The major question is: are these bipolar outflows driven by the same mechanism as those from low-mass stars? For example, the magnetocentrifugal wind scenarios predicts outflows which are morphological ...
High-Energy Astrophysics with Gamma
... LIRGs and ULIRGs, following simple population analysis, are to be detected as gamma-ray sources Starburst activity – cosmic ray populations – difussion Detailed analysis for ULIRG Arp 220 confirms this. Many other LIRGs (several tens) may appear in the forthcoming catalogs first multiwavelength ...
... LIRGs and ULIRGs, following simple population analysis, are to be detected as gamma-ray sources Starburst activity – cosmic ray populations – difussion Detailed analysis for ULIRG Arp 220 confirms this. Many other LIRGs (several tens) may appear in the forthcoming catalogs first multiwavelength ...
FIVE NEW TRANSITS OF THE SUPER
... & Valenti 2005). However, there are also individual exoplanets whose properties bear directly on theories of planet formation and evolution. One of the best examples is the transiting planet HD 149026b (Sato et al. 2005). Compared to Saturn, HD 149026b has a similar mass but its radius is 15% smalle ...
... & Valenti 2005). However, there are also individual exoplanets whose properties bear directly on theories of planet formation and evolution. One of the best examples is the transiting planet HD 149026b (Sato et al. 2005). Compared to Saturn, HD 149026b has a similar mass but its radius is 15% smalle ...
mg_colloq - University of Massachusetts Amherst
... If cETG formed in situ via some highly dissipative process (cold accretion?), then their progenitors must be among compact star-forming galaxies at z≥3. Are there any reasonable candidates? ...
... If cETG formed in situ via some highly dissipative process (cold accretion?), then their progenitors must be among compact star-forming galaxies at z≥3. Are there any reasonable candidates? ...
New Mass Loss Measurements from Astrospheric Lyα Absorption
... history of the Sun. The truncation of the power-law relation in Figure 3a leads to the mass-loss/age relation in Figure 3b being truncated as well at about t p 0.7 Gyr. Mass-loss rates for very active stars are significantly lower than would be predicted by the mass-loss/activity relation defined by ...
... history of the Sun. The truncation of the power-law relation in Figure 3a leads to the mass-loss/age relation in Figure 3b being truncated as well at about t p 0.7 Gyr. Mass-loss rates for very active stars are significantly lower than would be predicted by the mass-loss/activity relation defined by ...
High Resolution Observations of Hot Molecular Cores
... similar formation and disk properties as lower ...
... similar formation and disk properties as lower ...
Radio Bubbles, Cooling X-ray Gas, Galaxy Interactions, and Star
... as a cooling flow. Within the highly disturbed core revealed by Chandra Xray observations, 2A0335+096 hosts a luminous and highly structured optical emission-line system, including the brightest cluster galaxy and its companion. Our analysis reveals the presence of Hα emission bubbles, centered on t ...
... as a cooling flow. Within the highly disturbed core revealed by Chandra Xray observations, 2A0335+096 hosts a luminous and highly structured optical emission-line system, including the brightest cluster galaxy and its companion. Our analysis reveals the presence of Hα emission bubbles, centered on t ...
the paper - Universitäts
... of He 2-131 (middle), since its mass loss rate is obviously too small, as evidenced by the presence of almost only purely photospheric lines hardly influenced by the thin wind – indicating that this CSPN must have a much larger luminosity, because L is the major factor determining the mass loss rate ...
... of He 2-131 (middle), since its mass loss rate is obviously too small, as evidenced by the presence of almost only purely photospheric lines hardly influenced by the thin wind – indicating that this CSPN must have a much larger luminosity, because L is the major factor determining the mass loss rate ...
VERA Project : overview and current status
... High-precision Astrometric Missions Near-future projects for 10 micro-arcsec astrometry ...
... High-precision Astrometric Missions Near-future projects for 10 micro-arcsec astrometry ...
laboratory analysis of presolar silicate stardust from a
... to investigate a possible core-collapse supernova origin. No single zone in any of the models can reproduce the isotopic compositions; the same holds true for mixing of multiple zones. The highest 17 O/16 O ratios are predicted for the He/N zone with 17 O enrichments of factors of 4 (15 M SNII) and ...
... to investigate a possible core-collapse supernova origin. No single zone in any of the models can reproduce the isotopic compositions; the same holds true for mixing of multiple zones. The highest 17 O/16 O ratios are predicted for the He/N zone with 17 O enrichments of factors of 4 (15 M SNII) and ...
An X-ray and Radio Study of the Varying Expansion Velocities in
... In this work, we report on proper motion measurements of the forward shock, made from newly-obtained X-ray and radio data from Chandra and the Karl G. Jansky Very Large Array (VLA) in 2015 and 2013/14, respectively. While the measurements made by Reynoso et al. (1997) and Katsuda et al. (2010) follo ...
... In this work, we report on proper motion measurements of the forward shock, made from newly-obtained X-ray and radio data from Chandra and the Karl G. Jansky Very Large Array (VLA) in 2015 and 2013/14, respectively. While the measurements made by Reynoso et al. (1997) and Katsuda et al. (2010) follo ...
Self-Regulation of Star Formation in Low Metallicity Clouds
... After the recombination era, little information is accessible until z ∼ 5, after that we can observe objects such as galaxies and QSOs. On the other hand, the reionization of the intergalactic medium and the presence of heavy elements at high-z suggest that there are other populations of luminous ob ...
... After the recombination era, little information is accessible until z ∼ 5, after that we can observe objects such as galaxies and QSOs. On the other hand, the reionization of the intergalactic medium and the presence of heavy elements at high-z suggest that there are other populations of luminous ob ...
QU Carinae: Type Ia supernova in the making
... characteristics of the bright states of QU Car have been explored spectroscopically in Gilliland & Phillips (1982), Drew et al. (2003) and Paper I. As discussed in Paper I, in the bright state the system exhibits variable and irregular Balmer emission lines, He I and He II emission and one of the st ...
... characteristics of the bright states of QU Car have been explored spectroscopically in Gilliland & Phillips (1982), Drew et al. (2003) and Paper I. As discussed in Paper I, in the bright state the system exhibits variable and irregular Balmer emission lines, He I and He II emission and one of the st ...
ASTRONOMY AND ASTROPHYSICS The 10–200µm spectral
... of ∼ 3 (Storchi-Bergmann et al. 1995), lower than usually observed in AGNs. According to the ‘unified model’ (Antonucci 1993), broad emission lines are extinguished in Seyfert 2 galaxies by a dusty torus located at ≤ 100 pc from the nucleus, but they should be scattered into our line of sight by fre ...
... of ∼ 3 (Storchi-Bergmann et al. 1995), lower than usually observed in AGNs. According to the ‘unified model’ (Antonucci 1993), broad emission lines are extinguished in Seyfert 2 galaxies by a dusty torus located at ≤ 100 pc from the nucleus, but they should be scattered into our line of sight by fre ...
2-star-life-cycle-and-star-classification
... the same luminosity as the star Aldebaran approximately the same temperature as the Rigel. Algol is best classified as a A) main sequence star B) red giant star C) white dwarf star D) red dwarf star 60. Two stars of the same color are plotted on an H-R diagram. Star A is more luminous than star B. W ...
... the same luminosity as the star Aldebaran approximately the same temperature as the Rigel. Algol is best classified as a A) main sequence star B) red giant star C) white dwarf star D) red dwarf star 60. Two stars of the same color are plotted on an H-R diagram. Star A is more luminous than star B. W ...
The Circumstellar Medium of Massive Stars in Motion
... Massive stars are the main drivers of the evolution of the gaseous component of galaxies. They emit huge quantities of far-ultraviolet photons that ionise and heat surrounding gas; their strong winds drive shocks and gas flows; and their final explosions as supernovae or gamma-ray bursts generate po ...
... Massive stars are the main drivers of the evolution of the gaseous component of galaxies. They emit huge quantities of far-ultraviolet photons that ionise and heat surrounding gas; their strong winds drive shocks and gas flows; and their final explosions as supernovae or gamma-ray bursts generate po ...
Rotation - Indiana University Astronomy
... Alternative magnetic field indicators: collimated jets and energetic winds – Jets and winds are likely launched from the disk-magnetosphere boundary – Such winds are ubiquitous among low mass (M < 2 Msun) accreting PMS stars – Direct evidence of jets found among accreting stars as massive as M ~ 10 ...
... Alternative magnetic field indicators: collimated jets and energetic winds – Jets and winds are likely launched from the disk-magnetosphere boundary – Such winds are ubiquitous among low mass (M < 2 Msun) accreting PMS stars – Direct evidence of jets found among accreting stars as massive as M ~ 10 ...
Introduc on to the Fundamental Astrophysics Course
... the intergalac)c medium having about 10 to 100 atoms per cubic meter. Introduc)on to the Fundamental Astrophysics Course -‐ 2013 ...
... the intergalac)c medium having about 10 to 100 atoms per cubic meter. Introduc)on to the Fundamental Astrophysics Course -‐ 2013 ...
LAB #3 - GEOCITIES.ws
... Because what we know about stars is due solely to our analysis of their light, it is very important to develop further the idea of stellar magnitude, or how bright a star is. When the Greeks scientist Hipparcos determined the magnitude scale, he did it "by eye." The first stars that "came out" at ni ...
... Because what we know about stars is due solely to our analysis of their light, it is very important to develop further the idea of stellar magnitude, or how bright a star is. When the Greeks scientist Hipparcos determined the magnitude scale, he did it "by eye." The first stars that "came out" at ni ...
Cygnus X-1
Cygnus X-1 (abbreviated Cyg X-1) is a well-known galactic X-ray source, thought to be a black hole, in the constellation Cygnus. It was discovered in 1964 during a rocket flight and is one of the strongest X-ray sources seen from Earth, producing a peak X-ray flux density of 6977229999999999999♠2.3×10−23 Wm−2 Hz−1 (7003230000000000000♠2.3×103 Jansky). Cygnus X-1 was the first X-ray source widely accepted to be a black hole and it remains among the most studied astronomical objects in its class. The compact object is now estimated to have a mass about 14.8 times the mass of the Sun and has been shown to be too small to be any known kind of normal star, or other likely object besides a black hole. If so, the radius of its event horizon is about 7004440000000000000♠44 km.Cygnus X-1 belongs to a high-mass X-ray binary system about 7019574266339685654♠6070 ly from the Sun that includes a blue supergiant variable star designated HDE 226868 which it orbits at about 0.2 AU, or 20% of the distance from the Earth to the Sun. A stellar wind from the star provides material for an accretion disk around the X-ray source. Matter in the inner disk is heated to millions of degrees, generating the observed X-rays. A pair of jets, arranged perpendicular to the disk, are carrying part of the energy of the infalling material away into interstellar space.This system may belong to a stellar association called Cygnus OB3, which would mean that Cygnus X-1 is about five million years old and formed from a progenitor star that had more than 7001400000000000000♠40 solar masses. The majority of the star's mass was shed, most likely as a stellar wind. If this star had then exploded as a supernova, the resulting force would most likely have ejected the remnant from the system. Hence the star may have instead collapsed directly into a black hole.Cygnus X-1 was the subject of a friendly scientific wager between physicists Stephen Hawking and Kip Thorne in 1975, with Hawking betting that it was not a black hole. He conceded the bet in 1990 after observational data had strengthened the case that there was indeed a black hole in the system. This hypothesis has not been confirmed due to a lack of direct observation but has generally been accepted from indirect evidence.