IR Universe
... brightness of other sources observed by SPIRE (galaxies, stars, comets, etc.) will be measured by comparing them to Uranus. The reason for the choice of Uranus as the standard calibration source is that we already know quite accurately how warm it is. It turns out to be the best choice, since Uran ...
... brightness of other sources observed by SPIRE (galaxies, stars, comets, etc.) will be measured by comparing them to Uranus. The reason for the choice of Uranus as the standard calibration source is that we already know quite accurately how warm it is. It turns out to be the best choice, since Uran ...
Turbulent molecular gas and star formation in the shocked
... ridge, and much lower in the dense gas. Gas at pre-shock densities nH > 0.2 cm−3 experience shock velocities small enough (Vs < 200 km s−1 ) to retain most of its dust, cool, and become molecular within a few million years. We proposed that the H2 emission is associated with the dissipation of the k ...
... ridge, and much lower in the dense gas. Gas at pre-shock densities nH > 0.2 cm−3 experience shock velocities small enough (Vs < 200 km s−1 ) to retain most of its dust, cool, and become molecular within a few million years. We proposed that the H2 emission is associated with the dissipation of the k ...
On the Spiral Structure of the Milky Way Galaxy
... Spiral-arm tracers are well known: the arms concentrate the most massive gas clouds and young stars and clusters. Distances to these latter objects can currently be determined very precisely, but only for those within three to four kpc from the Sun. Direct data have recently begun to accumulate on l ...
... Spiral-arm tracers are well known: the arms concentrate the most massive gas clouds and young stars and clusters. Distances to these latter objects can currently be determined very precisely, but only for those within three to four kpc from the Sun. Direct data have recently begun to accumulate on l ...
The Current Status of Galaxy Formation
... However, the naı̈ve assumption that stellar mass follows halo mass, leads to too many small galaxies, too many big galaxies in the nearby universe, too few massive galaxies at high redshift, and too many baryons within the galaxy halos. In addition there are structural problems: for example, massive ...
... However, the naı̈ve assumption that stellar mass follows halo mass, leads to too many small galaxies, too many big galaxies in the nearby universe, too few massive galaxies at high redshift, and too many baryons within the galaxy halos. In addition there are structural problems: for example, massive ...
Circumstellar interaction in supernovae
... in the presence of the high energy magnetic fields. Radio emission is absorbed either by free-free absorption from the circumstellar medium or synchrotron self absorption depending upon the mass loss rate, ejecta velocity and electron temperature, magnetic field. Both absorption ...
... in the presence of the high energy magnetic fields. Radio emission is absorbed either by free-free absorption from the circumstellar medium or synchrotron self absorption depending upon the mass loss rate, ejecta velocity and electron temperature, magnetic field. Both absorption ...
PPT
... Abell 39 – Forty years on The perfect photoionisation benchmark for stellar evolution A39 - Visible Abell(1966) A220 ...
... Abell 39 – Forty years on The perfect photoionisation benchmark for stellar evolution A39 - Visible Abell(1966) A220 ...
Part 2 of Our Lecture
... (top right), and SED (below) – Model for the stellar photosphere emission (dark line) Model combining the stellar emission and the disk excess emission (white line) ...
... (top right), and SED (below) – Model for the stellar photosphere emission (dark line) Model combining the stellar emission and the disk excess emission (white line) ...
PDF
... the cold dark-matter model posits that each visible galaxy is embedded in a much larger darkmatter halo of non-baryonic material, which detached from the expanding cosmic plasma at early times. The gravitational merging of these halos drives the growth of structure and the rate of cooling of hydroge ...
... the cold dark-matter model posits that each visible galaxy is embedded in a much larger darkmatter halo of non-baryonic material, which detached from the expanding cosmic plasma at early times. The gravitational merging of these halos drives the growth of structure and the rate of cooling of hydroge ...
Birth - Wayne State University Physics and Astronomy
... undergo fusion into helium, with about 4 million tons turning to energy in the process This rate of hydrogen use means that eventually the Sun (and all other stars) will run out of central fuel ...
... undergo fusion into helium, with about 4 million tons turning to energy in the process This rate of hydrogen use means that eventually the Sun (and all other stars) will run out of central fuel ...
1 Introduction - Wiley-VCH
... young and massive stars, and by the synchrotron emission due to relativistic electrons accelerated in supernovae remnants spinning in week magnetic fields. Both emission processes are tightly related to recent star formation events and have a relative weight that changes with λ, where the free–free ...
... young and massive stars, and by the synchrotron emission due to relativistic electrons accelerated in supernovae remnants spinning in week magnetic fields. Both emission processes are tightly related to recent star formation events and have a relative weight that changes with λ, where the free–free ...
PH607 – Galaxies
... Hubble and collaborators began a systematic study of nearby galaxies which included measuring both their distance (Cepheids etc) and radial velocity. They soon noticed a remarkable trend: virtually all the galaxies they observed were moving away from our galaxy (redshifted) and the recession speed i ...
... Hubble and collaborators began a systematic study of nearby galaxies which included measuring both their distance (Cepheids etc) and radial velocity. They soon noticed a remarkable trend: virtually all the galaxies they observed were moving away from our galaxy (redshifted) and the recession speed i ...
The fuelling of local supermassive black holes
... to see t his picture. are needed to see this picture. ...
... to see t his picture. are needed to see this picture. ...
Leo Powerpoint
... Regulus, shining at the heart of Leo the Lion, is near the end of the list of first magnitude stars. At a distance of only 79 light years, it shines in our sky at magnitude 1.35. The Latin name means "the little king," the reference to a kingly star going back to ancient times. Regulus marks the end ...
... Regulus, shining at the heart of Leo the Lion, is near the end of the list of first magnitude stars. At a distance of only 79 light years, it shines in our sky at magnitude 1.35. The Latin name means "the little king," the reference to a kingly star going back to ancient times. Regulus marks the end ...
Populations of Galaxies and their Formation at z < 7
... integrated stellar mass in the universe increases gradually throughout this time suggesting that galaxy formation does not happen all at once. 3. Galaxies at high redshifts are peculiar and are likely undergoing mergers. The transition from mergers to normal Hubble types occurs at about z~1.5. Calcu ...
... integrated stellar mass in the universe increases gradually throughout this time suggesting that galaxy formation does not happen all at once. 3. Galaxies at high redshifts are peculiar and are likely undergoing mergers. The transition from mergers to normal Hubble types occurs at about z~1.5. Calcu ...
Primordial Planet Formation - University of California San Diego
... But because these were all planet mass bodies seen in remote galaxies, it was desirable to detect the objects in the Halo of our own Galaxy. Unfortunately the results of 2 research consortia that sought the primordial planet signal failed in spite of monitoring 7 million stars in the Large Magell ...
... But because these were all planet mass bodies seen in remote galaxies, it was desirable to detect the objects in the Halo of our own Galaxy. Unfortunately the results of 2 research consortia that sought the primordial planet signal failed in spite of monitoring 7 million stars in the Large Magell ...
The Evolution of Galaxy - Tufts Institute of Cosmology
... astronomers felt they at least understood the basic properties of clusters: They consisted of speeding galaxies bound together by huge amounts of dark matter. They were stable and immutable objects. Then came 1970. In that year a new satellite, named Uhuru (“freedom” in Swahili) in honor of its laun ...
... astronomers felt they at least understood the basic properties of clusters: They consisted of speeding galaxies bound together by huge amounts of dark matter. They were stable and immutable objects. Then came 1970. In that year a new satellite, named Uhuru (“freedom” in Swahili) in honor of its laun ...
STAR FORMATION IN ISOLATED DISK GALAXIES. II. SCHMIDT
... reproduces both the density threshold of 7 M pc2 for star formation and the global Schmidt law in disk galaxies. They also found that the nuclear starburst is associated with bar formation in the galactic center. Gerritsen & Icke (1997) included stellar feedback in similar two-component (gas and s ...
... reproduces both the density threshold of 7 M pc2 for star formation and the global Schmidt law in disk galaxies. They also found that the nuclear starburst is associated with bar formation in the galactic center. Gerritsen & Icke (1997) included stellar feedback in similar two-component (gas and s ...
Celebrating the centennial of a celestial yardstick
... assume that it has smatterings of other heavy metals, including gold, silver, and platinum. The planet has also had abundant volcanic activity (and may have some ongoing activity today), which is involved in concentrating such elements. Yet the amounts of these elements, their distribution, and many ...
... assume that it has smatterings of other heavy metals, including gold, silver, and platinum. The planet has also had abundant volcanic activity (and may have some ongoing activity today), which is involved in concentrating such elements. Yet the amounts of these elements, their distribution, and many ...
Document
... believe that galaxies are formed by the accumulation of baryonic matter in halos of dark matter. The nature of dark matter (DM) is one of the biggest riddles of the universe. It is an invisible but omnipresent form of matter that fills 23% of the universe (which is almost 5 times as much as the tota ...
... believe that galaxies are formed by the accumulation of baryonic matter in halos of dark matter. The nature of dark matter (DM) is one of the biggest riddles of the universe. It is an invisible but omnipresent form of matter that fills 23% of the universe (which is almost 5 times as much as the tota ...
Westerlund 1 : A Super-Star Cluster within the Milky Way
... identified in the Milky Way. Wd1 hosts a rich population of OB supergiants, Wolf-Rayet stars, Luminous Blue Variables, Yellow Hypergiants and Red Supergiants, from which we infer an age of 3-5Myr. For an adopted Kroupa IMF we derive a mass of 105 M and radius of 0.3pc for an estimated distance of 2 ...
... identified in the Milky Way. Wd1 hosts a rich population of OB supergiants, Wolf-Rayet stars, Luminous Blue Variables, Yellow Hypergiants and Red Supergiants, from which we infer an age of 3-5Myr. For an adopted Kroupa IMF we derive a mass of 105 M and radius of 0.3pc for an estimated distance of 2 ...
Here
... Galaxies. They are usually located at the center of clusters of galaxies, or in areas with dense population of galaxies. This excess emission indicates the presence of an extended halo. The cD halos are thought to belong to the cluster rather than to the galaxy. ...
... Galaxies. They are usually located at the center of clusters of galaxies, or in areas with dense population of galaxies. This excess emission indicates the presence of an extended halo. The cD halos are thought to belong to the cluster rather than to the galaxy. ...
Harikane
... Implications of Two Components. • Two strong star-forming regions. • A galaxy merger. • A combination of a galaxy and an outflow ...
... Implications of Two Components. • Two strong star-forming regions. • A galaxy merger. • A combination of a galaxy and an outflow ...
Formation and Disruption of Cosmological Low Mass Objects
... Today, we have a great deal of observational data concerning the early universe. However, we have very little information about the era referred to as the ‘dark ages’. Information regarding the era of recombination (with redshift z of about 103 ) can be obtained by the observation of cosmic microwav ...
... Today, we have a great deal of observational data concerning the early universe. However, we have very little information about the era referred to as the ‘dark ages’. Information regarding the era of recombination (with redshift z of about 103 ) can be obtained by the observation of cosmic microwav ...
Understanding the Astrophysics of Galaxy Evolution: the role of
... centers of dark matter halos are extremely complex. It is likely that we will never be able to model them “ab initio” using direct simulations in the way we now model dark matter evolution. One of the main problems hampering progress is the enormous dynamic range in scale that must considered when t ...
... centers of dark matter halos are extremely complex. It is likely that we will never be able to model them “ab initio” using direct simulations in the way we now model dark matter evolution. One of the main problems hampering progress is the enormous dynamic range in scale that must considered when t ...
the inclination of the dwarf irregular galaxy
... galaxy (Meurer et al. 2013; Zheng et al. 2013), lending support to the phenomenon of self-regulation by star formation, as suggested by Quirk (1972). However, although the value of the Qg -parameter is approximately constant across a galaxy, it varies from galaxy to galaxy, indicating that the ‘ther ...
... galaxy (Meurer et al. 2013; Zheng et al. 2013), lending support to the phenomenon of self-regulation by star formation, as suggested by Quirk (1972). However, although the value of the Qg -parameter is approximately constant across a galaxy, it varies from galaxy to galaxy, indicating that the ‘ther ...