environmental effects on galaxy evolution in nearby clusters
... cluster accretion of small groups. Ram pressure dominates in today clusters and is surely affecting the star formation history of galaxies but with less influence on their morphology. (III) The heterogeneous class of S0s galaxies, from bulge dominated to the disky S0s, is not the result of a single ...
... cluster accretion of small groups. Ram pressure dominates in today clusters and is surely affecting the star formation history of galaxies but with less influence on their morphology. (III) The heterogeneous class of S0s galaxies, from bulge dominated to the disky S0s, is not the result of a single ...
The evolution of low-metallicity massive stars - Argelander
... TWUIN stars are fast rotating massive stars that are extremely hot (90 kK), very bright and as compact as Wolf–Rayet stars. However, as opposed to Wolf–Rayet stars, their stellar winds are optically thin. As these hot objects emit intense UV radiation, we show that they can explain the unusually hig ...
... TWUIN stars are fast rotating massive stars that are extremely hot (90 kK), very bright and as compact as Wolf–Rayet stars. However, as opposed to Wolf–Rayet stars, their stellar winds are optically thin. As these hot objects emit intense UV radiation, we show that they can explain the unusually hig ...
The correlation between galaxy morphology and star
... galaxy morphologies, ranging from large, blue, disk-like galaxies to compact, red, early-type galaxies at z ∼ 2 with 16 massive galaxies in the Hubble Ultra Deep Field (HUDF). Cameron et al. (2011) also studied the rest-frame UV and optical morphologies with 1.5 < z < 3.5 galaxies determined by the ...
... galaxy morphologies, ranging from large, blue, disk-like galaxies to compact, red, early-type galaxies at z ∼ 2 with 16 massive galaxies in the Hubble Ultra Deep Field (HUDF). Cameron et al. (2011) also studied the rest-frame UV and optical morphologies with 1.5 < z < 3.5 galaxies determined by the ...
Tuomas Kangas
... use of the word nova to refer to such appearances of temporary star-like objects that lasted weeks or months before fading away. Novae were later distinguished from an intrinsically brighter class of events, called supernovae, by Walter Baade and Fritz Zwicky in 1934. Novae were found to be outburst ...
... use of the word nova to refer to such appearances of temporary star-like objects that lasted weeks or months before fading away. Novae were later distinguished from an intrinsically brighter class of events, called supernovae, by Walter Baade and Fritz Zwicky in 1934. Novae were found to be outburst ...
Chandra News March 2005 Published by the Chandra X-ray Center (CXC)
... a scan of the Galactic plane with a rocket-borne detector. In 1979, the first Einstein observation of this region showed that this source was the Carina Nebula, over 1 degree in extent - a bright (by present standards) diffuse source sprinkled with dozens of point-like O stars. Although η Carinae it ...
... a scan of the Galactic plane with a rocket-borne detector. In 1979, the first Einstein observation of this region showed that this source was the Carina Nebula, over 1 degree in extent - a bright (by present standards) diffuse source sprinkled with dozens of point-like O stars. Although η Carinae it ...
Star Formation in the Milky Way and Nearby Galaxies Further
... between the community studying individual star-forming regions and stars in the Milky Way (MW; also sometimes referred to as the Galaxy) and the largely extragalactic community that attempts to characterize the star-formation process on galactic and cosmological scales. Some aspects of this separati ...
... between the community studying individual star-forming regions and stars in the Milky Way (MW; also sometimes referred to as the Galaxy) and the largely extragalactic community that attempts to characterize the star-formation process on galactic and cosmological scales. Some aspects of this separati ...
DUSTiNGS III: Distribution of Intermediate
... radial profiles, these studies report the presence of both intermediate-age and older populations in the outer regions of a sub-sample of the galaxies studied. In this study, we selected the nine nearby dwarf galaxies that host > 90% of the identified variable AGB star candidates from the larger DUS ...
... radial profiles, these studies report the presence of both intermediate-age and older populations in the outer regions of a sub-sample of the galaxies studied. In this study, we selected the nine nearby dwarf galaxies that host > 90% of the identified variable AGB star candidates from the larger DUS ...
An X-Ray, Optical and Infra-red study of High-Mass X
... First and foremost I would like to thank my supervisor, Malcolm Coe, for his continued guidance and support. His drive to obtain and exploit all manner of data has given me a wealth of information on which to base my thesis and sent me to some of the world’s most incredible places in the process. I ...
... First and foremost I would like to thank my supervisor, Malcolm Coe, for his continued guidance and support. His drive to obtain and exploit all manner of data has given me a wealth of information on which to base my thesis and sent me to some of the world’s most incredible places in the process. I ...
THE UV-OPTICAL COLOR MAGNITUDE DIAGRAM. II. PHYSICAL
... We use the UV-optical color magnitude diagram in combination with spectroscopic and photometric measurements derived from the SDSS spectroscopic sample to measure the distribution of galaxies in the local universe (z < 0:25) and their physical properties as a function of specific star formation rate ...
... We use the UV-optical color magnitude diagram in combination with spectroscopic and photometric measurements derived from the SDSS spectroscopic sample to measure the distribution of galaxies in the local universe (z < 0:25) and their physical properties as a function of specific star formation rate ...
- Isaac Newton Group of Telescopes
... was confirmed to coincide with that of the stars of the cluster and, later, a precise photometric characterization was achieved. Several high resolution spectra between 600 and 900 nm were obtained with the WHT. These spectra confirmed the discovery of one of the coldest quasi-stellar objects known ...
... was confirmed to coincide with that of the stars of the cluster and, later, a precise photometric characterization was achieved. Several high resolution spectra between 600 and 900 nm were obtained with the WHT. These spectra confirmed the discovery of one of the coldest quasi-stellar objects known ...
The most metal-poor galaxies
... one looks, this quantity may vary substantially. For example in our Galaxy, the bulge, the solar neighbourhood and the halo differ in metallicity. The most metal-poor halo stars have heavy element abundances 10−4 times that of the Sun (Cayrel 1996) while stars in the Galactic centre may be three tim ...
... one looks, this quantity may vary substantially. For example in our Galaxy, the bulge, the solar neighbourhood and the halo differ in metallicity. The most metal-poor halo stars have heavy element abundances 10−4 times that of the Sun (Cayrel 1996) while stars in the Galactic centre may be three tim ...
OBSERVATIONS OF PHYSICAL PROCESSES IN
... cluster galaxies (BCGs) of those clusters. It has been known for a while that the state of the hot intracluster medium (ICM) gas in the core of a galaxy cluster, quantified as the central entropy of the gas, can be found in two particular states. Galaxy clusters with central entropies greater than 3 ...
... cluster galaxies (BCGs) of those clusters. It has been known for a while that the state of the hot intracluster medium (ICM) gas in the core of a galaxy cluster, quantified as the central entropy of the gas, can be found in two particular states. Galaxy clusters with central entropies greater than 3 ...
probing quasar environments with tunable filter
... AGN may be categorised in a variety of ways; a simple taxonomy is shown in table 1.1, in which they are classified according to two parameters: radio-loudness and the width of their emission lines. Sometimes, more than one class of object shares a given radio categorisation and optical type: these a ...
... AGN may be categorised in a variety of ways; a simple taxonomy is shown in table 1.1, in which they are classified according to two parameters: radio-loudness and the width of their emission lines. Sometimes, more than one class of object shares a given radio categorisation and optical type: these a ...
Stars, Galaxies, and Beyond
... I have prepared this summary to assist in learning some of the materials relevant to the courses named. These 300–level (junior) college courses have provided a satisfying opportunity to take a more detailed but still manageable look at astronomy and astrophysics applying to space well beyond the so ...
... I have prepared this summary to assist in learning some of the materials relevant to the courses named. These 300–level (junior) college courses have provided a satisfying opportunity to take a more detailed but still manageable look at astronomy and astrophysics applying to space well beyond the so ...
- National Optical Astronomy Observatory
... Movement of the Iron ions is restricted to the magnetic field lines from within the umbra to the edge of the penumbra. This is supported by the data, which shows an initial outward flow of the ions and then a downward flow near penumbra. Because the nickel particles are not ionized, their velocities ...
... Movement of the Iron ions is restricted to the magnetic field lines from within the umbra to the edge of the penumbra. This is supported by the data, which shows an initial outward flow of the ions and then a downward flow near penumbra. Because the nickel particles are not ionized, their velocities ...
Altair -- the ``hottest`` magnetically active star in X-rays
... that covers in total three to four stellar rotations. However, the uncertainties in the relevant stellar parameters (V sin i, i, R) allow a range of rotation periods with values around 9.5 ± 1 h. Further, our data is not continuous, and especially the data gap of two weeks between both observations ...
... that covers in total three to four stellar rotations. However, the uncertainties in the relevant stellar parameters (V sin i, i, R) allow a range of rotation periods with values around 9.5 ± 1 h. Further, our data is not continuous, and especially the data gap of two weeks between both observations ...
The old globular cluster system of the dIrr galaxy NGC 1427A in the
... that the density distribution of GCs in the outskirts of the Fornax central cD galaxy NGC 1399 may not be spherically symmetric. We derive a present-day specific frequency SN of 1.6 for NGC 1427A, a value significantly larger than what is observed in the Local Group dwarf irregular galaxies and comp ...
... that the density distribution of GCs in the outskirts of the Fornax central cD galaxy NGC 1399 may not be spherically symmetric. We derive a present-day specific frequency SN of 1.6 for NGC 1427A, a value significantly larger than what is observed in the Local Group dwarf irregular galaxies and comp ...
Digital Universe Guide - American Museum of Natural History
... 2. Unzip the downloaded file if your operating system does not unpack it automatically. (On Mac OS X, the file will appear as a mounted disk on your system.) 3. Optional: Move the resulting Digital Universe folder to any location in your file system. (The download is completely self-contained and do ...
... 2. Unzip the downloaded file if your operating system does not unpack it automatically. (On Mac OS X, the file will appear as a mounted disk on your system.) 3. Optional: Move the resulting Digital Universe folder to any location in your file system. (The download is completely self-contained and do ...
Preliminary Talk Abstract Book - MoCA
... galaxy growth. I will present the results of theoretical models for the joint evolution of mass, size and velocity dispersion of ETGs in a LambdaCDM universe, based on cosmological and binary-merging N-body simulations. Models and observations are consistent at 0 < z < 2, while there is tension at z ...
... galaxy growth. I will present the results of theoretical models for the joint evolution of mass, size and velocity dispersion of ETGs in a LambdaCDM universe, based on cosmological and binary-merging N-body simulations. Models and observations are consistent at 0 < z < 2, while there is tension at z ...
Radio Emission Toward Regions of Massive Star Formation
... stars with accretion disks and bipolar outflows have been directly observed (Kraus et al. 2010). Therefore, there must be some other important physics simple models do not take into account. The review by Zinnecker & Yorke (2007) discusses three prevailing theories: monolithic collapse in cores with ...
... stars with accretion disks and bipolar outflows have been directly observed (Kraus et al. 2010). Therefore, there must be some other important physics simple models do not take into account. The review by Zinnecker & Yorke (2007) discusses three prevailing theories: monolithic collapse in cores with ...
Confirmation of Hostless Type Ia Supernovae Using Hubble Space
... Multi-Epoch Nearby Cluster Survey. Assuming a steep faint-end slope for the galaxy cluster luminosity function (αd = −1.5), our data includes all but . 0.2% percent of the stellar mass in cluster galaxies (. 0.005% with αd = −1.0), a factor of 10 better than our ground-based imaging. Two of the four ...
... Multi-Epoch Nearby Cluster Survey. Assuming a steep faint-end slope for the galaxy cluster luminosity function (αd = −1.5), our data includes all but . 0.2% percent of the stellar mass in cluster galaxies (. 0.005% with αd = −1.0), a factor of 10 better than our ground-based imaging. Two of the four ...
2 Justification and benefits in joining TMT
... reveal that the Universe is dominated by dark matter and dark energy. The nature of these two dark components is the most fundamental question in (astro-)physics today. The discovery of more than 400 extrasolar planet systems indicates that our solar system may be the exception rather than the norm; ...
... reveal that the Universe is dominated by dark matter and dark energy. The nature of these two dark components is the most fundamental question in (astro-)physics today. The discovery of more than 400 extrasolar planet systems indicates that our solar system may be the exception rather than the norm; ...
FLARE SWG theme 3: high
... Pro: deeper spectroscopic follow-up observations Con: shorter wavelength (<2.5um) spectroscopy more limiting for quasar identification; however, again, most of first quasar emission lines at <2um ...
... Pro: deeper spectroscopic follow-up observations Con: shorter wavelength (<2.5um) spectroscopy more limiting for quasar identification; however, again, most of first quasar emission lines at <2um ...
Science Case for the Chinese Participation of TMT
... reveal that the Universe is dominated by dark matter and dark energy. The nature of these two dark components is the most fundamental question in (astro-)physics today. The discovery of more than 400 extrasolar planet systems indicates that our solar system may be the exception rather than the norm; ...
... reveal that the Universe is dominated by dark matter and dark energy. The nature of these two dark components is the most fundamental question in (astro-)physics today. The discovery of more than 400 extrasolar planet systems indicates that our solar system may be the exception rather than the norm; ...
Annual Report 2011 - Max Planck Institute for Astrophysics
... had an internationally-recognized numerical astrophysics program that is unparalleled by any other The Max-Planck-Institut für Astrophysik, called institution of similar size. the MPA for short, was founded in 1958 under the directorship of Ludwig Biermann. It was first established as an offshoot of ...
... had an internationally-recognized numerical astrophysics program that is unparalleled by any other The Max-Planck-Institut für Astrophysik, called institution of similar size. the MPA for short, was founded in 1958 under the directorship of Ludwig Biermann. It was first established as an offshoot of ...
Gamma-ray burst
Gamma-ray bursts (GRBs) are flashes of gamma rays associated with extremely energetic explosions that have been observed in distant galaxies. They are the brightest electromagnetic events known to occur in the universe. Bursts can last from ten milliseconds to several hours. The initial burst is usually followed by a longer-lived ""afterglow"" emitted at longer wavelengths (X-ray, ultraviolet, optical, infrared, microwave and radio).Most observed GRBs are believed to consist of a narrow beam of intense radiation released during a supernova or hypernova as a rapidly rotating, high-mass star collapses to form a neutron star, quark star, or black hole. A subclass of GRBs (the ""short"" bursts) appear to originate from a different process – this may be due to the merger of binary neutron stars. The cause of the precursor burst observed in some of these short events may be due to the development of a resonance between the crust and core of such stars as a result of the massive tidal forces experienced in the seconds leading up to their collision, causing the entire crust of the star to shatter.The sources of most GRBs are billions of light years away from Earth, implying that the explosions are both extremely energetic (a typical burst releases as much energy in a few seconds as the Sun will in its entire 10-billion-year lifetime) and extremely rare (a few per galaxy per million years). All observed GRBs have originated from outside the Milky Way galaxy, although a related class of phenomena, soft gamma repeater flares, are associated with magnetars within the Milky Way. It has been hypothesized that a gamma-ray burst in the Milky Way, pointing directly towards the Earth, could cause a mass extinction event.GRBs were first detected in 1967 by the Vela satellites, a series of satellites designed to detect covert nuclear weapons tests. Hundreds of theoretical models were proposed to explain these bursts in the years following their discovery, such as collisions between comets and neutron stars. Little information was available to verify these models until the 1997 detection of the first X-ray and optical afterglows and direct measurement of their redshifts using optical spectroscopy, and thus their distances and energy outputs. These discoveries, and subsequent studies of the galaxies and supernovae associated with the bursts, clarified the distance and luminosity of GRBs. These facts definitively placed them in distant galaxies and also connected long GRBs with the explosion of massive stars, the only possible source for the energy outputs observed.