Gas Mass Fractions and the Evolution of Spiral Galaxies
... luminosity and surface brightness. It is not correlated with linear size. Gas fraction varies with luminosity and surface brightness at the same rate, indicating evolution at fixed size. Dim galaxies are clearly less evolved than bright ones, having consumed only ∼ 1/2 of their gas. This resolves th ...
... luminosity and surface brightness. It is not correlated with linear size. Gas fraction varies with luminosity and surface brightness at the same rate, indicating evolution at fixed size. Dim galaxies are clearly less evolved than bright ones, having consumed only ∼ 1/2 of their gas. This resolves th ...
POSTERS SESSION I: Atmospheres of Massive Stars
... Here, we present a technique to derive the rotation rates of WR stars from a periodic wind phenomenon. It has been shown that in most OB stars (if not all), magnetic activity or pulsations at the stellar surface induce locally larger mass loss, giving birth to spiral-like density structures that cor ...
... Here, we present a technique to derive the rotation rates of WR stars from a periodic wind phenomenon. It has been shown that in most OB stars (if not all), magnetic activity or pulsations at the stellar surface induce locally larger mass loss, giving birth to spiral-like density structures that cor ...
The Terrestrial Planet Finder Mission
... ing through the pupil plane from a plane pupil plane given direction at a certain point on the focal plane, say (0, 0). However, the wave nature of light makes it impossible to concentrate all of the light at a point. Instead, a small disk, called the Airy disk, with diffraction rings around it appe ...
... ing through the pupil plane from a plane pupil plane given direction at a certain point on the focal plane, say (0, 0). However, the wave nature of light makes it impossible to concentrate all of the light at a point. Instead, a small disk, called the Airy disk, with diffraction rings around it appe ...
A new method to determine the mean density of massive Solar
... distances to the Sun (Fig. 2); therefore their mean density trend is subtle. We allocate the asteroids into two groups, according to the values of the mean density. The first group includes a few asteroids with their mean densities higher than 4 g/cm 3. The mean densities of these asteroids show the ...
... distances to the Sun (Fig. 2); therefore their mean density trend is subtle. We allocate the asteroids into two groups, according to the values of the mean density. The first group includes a few asteroids with their mean densities higher than 4 g/cm 3. The mean densities of these asteroids show the ...
Lecture 3 - University of Washington
... • The spiral arms are overdense regions which move around at a different speed than star: stars thus move in and out of the spiral arm • How these density waves are set up is unclear, but it may have to do with interactions. Once they are set up, they must last for a long enough time to be consisten ...
... • The spiral arms are overdense regions which move around at a different speed than star: stars thus move in and out of the spiral arm • How these density waves are set up is unclear, but it may have to do with interactions. Once they are set up, they must last for a long enough time to be consisten ...
Evolution of the atomic and molecular gas content of galaxies
... gas and much lower cosmic H2 fraction over the entire redshift range probed than the pressure based recipe. These strong differences in Hi mass function and cosmic density between the two recipes are driven by low mass galaxies (log (M∗ /M⊙ ) 6 7) residing in low mass halos (log (Mvir /M⊙ ) 6 10). B ...
... gas and much lower cosmic H2 fraction over the entire redshift range probed than the pressure based recipe. These strong differences in Hi mass function and cosmic density between the two recipes are driven by low mass galaxies (log (M∗ /M⊙ ) 6 7) residing in low mass halos (log (Mvir /M⊙ ) 6 10). B ...
Super-Eddington outburst in a binary system: V4641 Sgr Mikhail Revnivtsev, Marat Gilfanov
... • When the accretion rate decreased the envelope vanished • X-ray observations support this picture: we have detected the change in the X-ray absorption column, smeared and probably delayed variability of fluorescent Fe line • Source is also interesting from the point of view of unusually high Lopt/ ...
... • When the accretion rate decreased the envelope vanished • X-ray observations support this picture: we have detected the change in the X-ray absorption column, smeared and probably delayed variability of fluorescent Fe line • Source is also interesting from the point of view of unusually high Lopt/ ...
Observations and Theory of Dynamical Triggers for Star Formation
... or recollects into denser cores in which star clusters eventually form. Large scale triggering (Table 3): accumulation of gas into an expanding shell or ring partially surrounding the pressure source, with star formation in the shell or ring presumably triggered by gravitational collapse of swept-up ...
... or recollects into denser cores in which star clusters eventually form. Large scale triggering (Table 3): accumulation of gas into an expanding shell or ring partially surrounding the pressure source, with star formation in the shell or ring presumably triggered by gravitational collapse of swept-up ...
Evolution of the atomic and molecular gas content of galaxies
... gas and much lower cosmic H2 fraction over the entire redshift range probed than the pressure based recipe. These strong differences in Hi mass function and cosmic density between the two recipes are driven by low mass galaxies (log (M∗ /M⊙ ) 6 7) residing in low mass halos (log (Mvir /M⊙ ) 6 10). B ...
... gas and much lower cosmic H2 fraction over the entire redshift range probed than the pressure based recipe. These strong differences in Hi mass function and cosmic density between the two recipes are driven by low mass galaxies (log (M∗ /M⊙ ) 6 7) residing in low mass halos (log (Mvir /M⊙ ) 6 10). B ...
V. - Humboldt Digital Library
... and theory of the universe. How, by means of existing things, a small part of their genetic history is laid open. Different phases of the theory of the universe, attempts to comprehend the order of nature. Most ancient fundamental conception of the Hellenic mind: physiologic phantasies of the Ionian ...
... and theory of the universe. How, by means of existing things, a small part of their genetic history is laid open. Different phases of the theory of the universe, attempts to comprehend the order of nature. Most ancient fundamental conception of the Hellenic mind: physiologic phantasies of the Ionian ...
structure and evolution of white dwarfs and their
... ideas remain unchanged. However, importantly, they have also hardly been tested by direct observation. Theoretical and observational study of stellar evolution has placed white dwarfs as one possible end point of the process. In general terms, all stars with masses below about eight times that of th ...
... ideas remain unchanged. However, importantly, they have also hardly been tested by direct observation. Theoretical and observational study of stellar evolution has placed white dwarfs as one possible end point of the process. In general terms, all stars with masses below about eight times that of th ...
The Oort cloud as a remnant of the protosolar nebula
... Perhaps the only theory without any shortcoming is the theory of creation in situ published by Hills in 1982. He suggested that pressure due to the radiation from the Sun and neighbouring protostars may have forced the coagulation into comets of dust grains in collapsing layers of the protosun at di ...
... Perhaps the only theory without any shortcoming is the theory of creation in situ published by Hills in 1982. He suggested that pressure due to the radiation from the Sun and neighbouring protostars may have forced the coagulation into comets of dust grains in collapsing layers of the protosun at di ...
Evolution of low mass stars
... The HRD inspired an English astronomer, Sir Arthur Stanley Eddington (18821944), when Russell visited London and presented his diagram at a meeting of the Royal Astronomical Society in 1913 (Eisberg, 2002). At the time, Eddington was the chief assistant of the Royal Greenwich Observatory. In 1926 Ed ...
... The HRD inspired an English astronomer, Sir Arthur Stanley Eddington (18821944), when Russell visited London and presented his diagram at a meeting of the Royal Astronomical Society in 1913 (Eisberg, 2002). At the time, Eddington was the chief assistant of the Royal Greenwich Observatory. In 1926 Ed ...
Where stars form: inside-out growth and coherent star formation from
... 2676 galaxies enabling a division into subsamples based on stellar mass and star formation rate. By creating deep stacked Hα images, we reach surface brightness limits of 1 × 10−18 erg s−1 cm−2 arcsec−2 , allowing us to map the distribution of ionized gas out to greater than 10 kpc for typical L∗ ga ...
... 2676 galaxies enabling a division into subsamples based on stellar mass and star formation rate. By creating deep stacked Hα images, we reach surface brightness limits of 1 × 10−18 erg s−1 cm−2 arcsec−2 , allowing us to map the distribution of ionized gas out to greater than 10 kpc for typical L∗ ga ...
New brown dwarfs and giant planets
... ~50% trig/50% photo parallaxes Proper motions for all (U, V, W) velocities ...
... ~50% trig/50% photo parallaxes Proper motions for all (U, V, W) velocities ...
implication on the mass and
... color maps) : 40% of LIRGs are large disks (Zheng et al, 2004, A&A) ! Lilly et al (1998) large disk sample (rdisk > 4 h50-1 kpc) at 0.5 < z < 1: 32 (+/-13)% of them are LIRGs ! LIRGs have large stellar masses: 1.4 1010MO
... color maps) : 40% of LIRGs are large disks (Zheng et al, 2004, A&A) ! Lilly et al (1998) large disk sample (rdisk > 4 h50-1 kpc) at 0.5 < z < 1: 32 (+/-13)% of them are LIRGs ! LIRGs have large stellar masses: 1.4 1010MO
The Milky Way as a galaxy
... thus larger distances, became possible with the astrometric satellite Hipparcos. It operated between November 1989 and March 1993 and measured the positions and trigonometric parallaxes of about 120 000 bright stars, with a precision of 0:00 001 for the brighter targets. With Hipparcos the method ...
... thus larger distances, became possible with the astrometric satellite Hipparcos. It operated between November 1989 and March 1993 and measured the positions and trigonometric parallaxes of about 120 000 bright stars, with a precision of 0:00 001 for the brighter targets. With Hipparcos the method ...
Red supergiants and the past of Cygnus OB2
... candidates, including four that have been already classified as M supergiants in the literature. Results. We confirm the presence of seven red supergiants in the region and argue that they are probably physically associated with Cygnus OB2. Their location is roughly coincident with that of the older ...
... candidates, including four that have been already classified as M supergiants in the literature. Results. We confirm the presence of seven red supergiants in the region and argue that they are probably physically associated with Cygnus OB2. Their location is roughly coincident with that of the older ...