Gas Mass Fractions and the Evolution of Spiral Galaxies
... We show that the gas mass fraction of spiral galaxies is strongly correlated with 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 e ...
... We show that the gas mass fraction of spiral galaxies is strongly correlated with 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 e ...
Science Case for the Chinese Participation of TMT
... questions with the next generation extremely large class telescopes such as the Thirty Meter Telescope (TMT). The Chinese participation in the TMT will place China in the forefront of astronomy for many decades to come; it can be a transformational experience for Chinese astronomy in terms of scienc ...
... questions with the next generation extremely large class telescopes such as the Thirty Meter Telescope (TMT). The Chinese participation in the TMT will place China in the forefront of astronomy for many decades to come; it can be a transformational experience for Chinese astronomy in terms of scienc ...
Mapping the Pathways of Galaxy Transformation Across Time and
... their recent star formation histories, and to place them on a timeline post-burst. I will discuss these results and other new work detailing how their stellar populations, gas content, and black hole properties evolve. ...
... their recent star formation histories, and to place them on a timeline post-burst. I will discuss these results and other new work detailing how their stellar populations, gas content, and black hole properties evolve. ...
Variations in the Star Formation Efficiency of the Dense Molecular
... We present a new survey of HCN (1–0) emission, a tracer of dense molecular gas, focused on the littleexplored regime of normal star-forming galaxy disks. Combining HCN, CO, and infrared (IR) emission, we investigate the role of dense gas in star formation, finding systematic variations in both the a ...
... We present a new survey of HCN (1–0) emission, a tracer of dense molecular gas, focused on the littleexplored regime of normal star-forming galaxy disks. Combining HCN, CO, and infrared (IR) emission, we investigate the role of dense gas in star formation, finding systematic variations in both the a ...
The science case for - Astrophysics
... Can we meet the grand challenge to trace star formation back to the very first star ever formed? By discovering and analysing distant galaxies, gas clouds, and supernovae, the history of star formation, and the creation history of the chemical elements can be quantified. What were the first objects? ...
... Can we meet the grand challenge to trace star formation back to the very first star ever formed? By discovering and analysing distant galaxies, gas clouds, and supernovae, the history of star formation, and the creation history of the chemical elements can be quantified. What were the first objects? ...
GALEX and Star Formation
... where multiple stellar generations contribute significantly to the light (Fig.s 1 and 2). Finally, UV fluxes are more sensitive to dust, which plays a major role in star formation, as will be discussed in Section 2.3. Massive stars drive the chemical evolution of the Universe, enriching the interste ...
... where multiple stellar generations contribute significantly to the light (Fig.s 1 and 2). Finally, UV fluxes are more sensitive to dust, which plays a major role in star formation, as will be discussed in Section 2.3. Massive stars drive the chemical evolution of the Universe, enriching the interste ...
Rest-frame Optical Spectra: A Window into Galaxy Formation at z~2
... • With a statistical sample already in early MOSDEF data, we can see that the offset is real! • If line ratios are different in high redshift galaxies, suggests differences in physical conditions in HII regions. • Higher ionization parameter (geometry of stars relative to gas); harder ionizing ra ...
... • With a statistical sample already in early MOSDEF data, we can see that the offset is real! • If line ratios are different in high redshift galaxies, suggests differences in physical conditions in HII regions. • Higher ionization parameter (geometry of stars relative to gas); harder ionizing ra ...
Project Description - SDSS-III
... Galactic Evolution Experiment (APOGEE) will use high-resolution (R ∼ 20, 000 at λ ∼ 1.6µm), high signal-to-noise (S/N ∼ 100) infrared spectroscopy to penetrate the dust that obscures the inner Galaxy from our view, measuring radial velocities, spectral types, and detailed elemental abundances of 100 ...
... Galactic Evolution Experiment (APOGEE) will use high-resolution (R ∼ 20, 000 at λ ∼ 1.6µm), high signal-to-noise (S/N ∼ 100) infrared spectroscopy to penetrate the dust that obscures the inner Galaxy from our view, measuring radial velocities, spectral types, and detailed elemental abundances of 100 ...
Lecture 2
... Completing the z~3 Picture • Using molecular line emission at z=3, could probe cool gas • “low-excitation lines will map out a larger fraction of the ISM in these galaxies and…study in detail the spacially resolved kinematic structure of most of the gas…which resides in the cold phase” (Carilli & B ...
... Completing the z~3 Picture • Using molecular line emission at z=3, could probe cool gas • “low-excitation lines will map out a larger fraction of the ISM in these galaxies and…study in detail the spacially resolved kinematic structure of most of the gas…which resides in the cold phase” (Carilli & B ...
The cosmological significance of high
... We have used new and archival infrared and radio observations to search for a dwarf galaxy associated with the high-velocity cloud (HVC) known as Complex H. Complex H is a large (Ω & 400 deg2 ) and probably nearby (d = 27 kpc) HVC whose location in the Galactic plane has hampered previous investigat ...
... We have used new and archival infrared and radio observations to search for a dwarf galaxy associated with the high-velocity cloud (HVC) known as Complex H. Complex H is a large (Ω & 400 deg2 ) and probably nearby (d = 27 kpc) HVC whose location in the Galactic plane has hampered previous investigat ...
Elliptical Galaxies
... Dark haloes: mass at large radius Spiral galaxy rotation curves have been used to show that they are embedded in dark haloes that contain three to ten times as much mass as is visible in stars, gas and dust. Can dark haloes be detected in elliptical galaxies? The velocity dispersion in many galaxies ...
... Dark haloes: mass at large radius Spiral galaxy rotation curves have been used to show that they are embedded in dark haloes that contain three to ten times as much mass as is visible in stars, gas and dust. Can dark haloes be detected in elliptical galaxies? The velocity dispersion in many galaxies ...
The Swift satellite lives up to its name, revealing cosmic
... tendency towards associations with late-type (elliptical) galaxies at z<1 with very little or no current star formation. If these bursts originate in a binary merger (the currently favoured model) we might expect to see them more frequently in low density environments, kicked out of the denser regio ...
... tendency towards associations with late-type (elliptical) galaxies at z<1 with very little or no current star formation. If these bursts originate in a binary merger (the currently favoured model) we might expect to see them more frequently in low density environments, kicked out of the denser regio ...
STELLAR AGE VERSUS MASS OF EARLY
... single burst of finite length lies within the observed color range, although still somewhat offset from the mean values. The best match is provided by the model population that formed through a constant star formation rate with a varying truncation time, which lies relatively close to the observed m ...
... single burst of finite length lies within the observed color range, although still somewhat offset from the mean values. The best match is provided by the model population that formed through a constant star formation rate with a varying truncation time, which lies relatively close to the observed m ...
Hubble Space Telescope Imaging of Post
... Numerical simulations have successfully reproduced the physical properties of elliptical galaxies and bulges through major mergers of gas-rich disk galaxies (Granato et al. 2004; Di Matteo et al. 2005; Hopkins et al. 2006). These simulations follow star formation and BH growth simultaneously during ...
... Numerical simulations have successfully reproduced the physical properties of elliptical galaxies and bulges through major mergers of gas-rich disk galaxies (Granato et al. 2004; Di Matteo et al. 2005; Hopkins et al. 2006). These simulations follow star formation and BH growth simultaneously during ...
Galaxies - WordPress.com
... A galaxies occasionally collide with one another, particularly within cluster of galaxies B galaxies are so closely packed in the universe that they are always interacting with one another C galaxies are so widely separated that they never interact or collide D the universe is composed of one giant ...
... A galaxies occasionally collide with one another, particularly within cluster of galaxies B galaxies are so closely packed in the universe that they are always interacting with one another C galaxies are so widely separated that they never interact or collide D the universe is composed of one giant ...
Lab 14 Galaxy Morphology
... appeared similar to comets, but did not move. Others of these nebulae were resolved into clusters of stars as bigger telescopes were constructed, and used to examine them. Some of these fuzzy nebulae, however, did not break-up into stars no matter how big a telescope was used to look at them. While ...
... appeared similar to comets, but did not move. Others of these nebulae were resolved into clusters of stars as bigger telescopes were constructed, and used to examine them. Some of these fuzzy nebulae, however, did not break-up into stars no matter how big a telescope was used to look at them. While ...
Galaxies
... b. the barred spiral galaxies. c. the dwarf elliptical galaxies. d. the irregular galaxies. e. the giant elliptical galaxies. We should expect galaxies to collide fairly often because a. they are large with respect to their separation distances. b. galaxies contain large amounts of neutral hydrogen. ...
... b. the barred spiral galaxies. c. the dwarf elliptical galaxies. d. the irregular galaxies. e. the giant elliptical galaxies. We should expect galaxies to collide fairly often because a. they are large with respect to their separation distances. b. galaxies contain large amounts of neutral hydrogen. ...
Masses of Dwarf Satellites of the Milky Way
... Fig. 1.— Projected velocity dispersion profiles for eight bright dSphs, from Magellan/MMFS and MMT/Hectochelle data. Over-plotted are profiles calculated from isothermal, power-law, NFW and cored halos considered as prospective “universal” dSph halos (Section 5). For each type of halo we fit only fo ...
... Fig. 1.— Projected velocity dispersion profiles for eight bright dSphs, from Magellan/MMFS and MMT/Hectochelle data. Over-plotted are profiles calculated from isothermal, power-law, NFW and cored halos considered as prospective “universal” dSph halos (Section 5). For each type of halo we fit only fo ...
2. The X-ray-Radio correlation for bulgeless galaxies
... Correlations between the X-ray and Radio emissions are observed for both galaxies with Active Galactic Nuclei (AGN) and in Star Forming galaxies. For the first case, the Xray/Radio correlation seems to present different slopes for Radio-loud and Radio-quiet AGN and may be used to estimate the mass o ...
... Correlations between the X-ray and Radio emissions are observed for both galaxies with Active Galactic Nuclei (AGN) and in Star Forming galaxies. For the first case, the Xray/Radio correlation seems to present different slopes for Radio-loud and Radio-quiet AGN and may be used to estimate the mass o ...
Preface
... its first creation in the Universe. The first generation of cosmic dust must have been produced less than 1 Gyr after the Big Bang, for the reason that more than 108 solar masses of dust has been found in distant QSOs powered by super-massive black holes sitting at the center of a galaxy at that age ...
... its first creation in the Universe. The first generation of cosmic dust must have been produced less than 1 Gyr after the Big Bang, for the reason that more than 108 solar masses of dust has been found in distant QSOs powered by super-massive black holes sitting at the center of a galaxy at that age ...
Simulations of the galaxy population constrained by observations
... star formation rates and ages, clustering and the evolution of the stellar mass-halo mass relation. This work uses merger trees from two very large dark matter simulations, which are well adapted to study galaxy formation physics on a variety of scales. The Millennium Simulation (Springel et al. 200 ...
... star formation rates and ages, clustering and the evolution of the stellar mass-halo mass relation. This work uses merger trees from two very large dark matter simulations, which are well adapted to study galaxy formation physics on a variety of scales. The Millennium Simulation (Springel et al. 200 ...
Article PDF - IOPscience
... A major problem in extragalactic astronomy is the inability to distinguish in a robust, physical, and modelindependent way how galaxy populations are physically related to each other and to their formation histories. A similar, but distinct, and also long-standing question is whether the structural ...
... A major problem in extragalactic astronomy is the inability to distinguish in a robust, physical, and modelindependent way how galaxy populations are physically related to each other and to their formation histories. A similar, but distinct, and also long-standing question is whether the structural ...
Stellar populations in the nuclear regions of nearby radio galaxies
... stellar clusters (e.g. Perry & Dyson 1985; Peterson 1992); and also pure starbursts without black holes (e.g. Terlevich & Melnick 1985; Terlevich et al. 1992). The evidence for starbursts in Seyfert nuclei strongly supports some kind of connection. However, it is yet to be demonstrated that starburs ...
... stellar clusters (e.g. Perry & Dyson 1985; Peterson 1992); and also pure starbursts without black holes (e.g. Terlevich & Melnick 1985; Terlevich et al. 1992). The evidence for starbursts in Seyfert nuclei strongly supports some kind of connection. However, it is yet to be demonstrated that starburs ...
Stars, Galaxies, Superuniverses and the Urantia Book, by Frederick
... throughout the master universe the minimum distance between stars would be about 1,400 light years. Actually, the stars cluster into globular clusters, galaxies, clusters of galaxies, and galactic superclusters where the stellar density is significantly greater than the average density, and leaving ...
... throughout the master universe the minimum distance between stars would be about 1,400 light years. Actually, the stars cluster into globular clusters, galaxies, clusters of galaxies, and galactic superclusters where the stellar density is significantly greater than the average density, and leaving ...
Mylavaram - Intellectual Archive
... but converts time as a relative concept. This is the most serious blunder which the physicists have committed. In Special Theory of Relativity, Einstein without assigning any reason to the invariability of velocity of electromagnetic radiation in the first postulate has assumed that laws of physics ...
... but converts time as a relative concept. This is the most serious blunder which the physicists have committed. In Special Theory of Relativity, Einstein without assigning any reason to the invariability of velocity of electromagnetic radiation in the first postulate has assumed that laws of physics ...