EVOLUTION OF THE QUASAR POPULATION AT HIGH REDSHIFT
... masses are found to be 109 ∼ 1010 M¯ and Eddington luminosity ratios are of order unity. Our Spitzer observations show that most of z ∼ 6 quasars have prominent emission from hot dust. Their SEDs are similar to those of low-redshift quasars at rest-frame 0.15–3.5 µm, suggesting that their accretion ...
... masses are found to be 109 ∼ 1010 M¯ and Eddington luminosity ratios are of order unity. Our Spitzer observations show that most of z ∼ 6 quasars have prominent emission from hot dust. Their SEDs are similar to those of low-redshift quasars at rest-frame 0.15–3.5 µm, suggesting that their accretion ...
Local Universe Supernovae and Their Host Galaxies
... • occur in all type of galaxies (E included) • in spirals, not strongly associated with HII regions ...
... • occur in all type of galaxies (E included) • in spirals, not strongly associated with HII regions ...
Catalogues of isolated galaxies, isolated pairs, and isolated triplets
... Separating the effects of interaction-driven evolution in the observed galaxy properties is not trivial. Galaxies suffer intrinsic and secular evolution processes, but they are also exposed to the influences of their local and large-scale environments. There is a strong correlation of galaxy propert ...
... Separating the effects of interaction-driven evolution in the observed galaxy properties is not trivial. Galaxies suffer intrinsic and secular evolution processes, but they are also exposed to the influences of their local and large-scale environments. There is a strong correlation of galaxy propert ...
Leakage of ionizing radiation from the nearby galaxy Tololo 1247
... LyC leakage preferably at a wider range of redshifts than what is currently available. In fact, since the only direct detections at z < 3 are the already mentioned galaxies Haro 11, and Tol 1247-232, this follow up study of Tol 1247-232 becomes increasingly important. Assuming that the underlying me ...
... LyC leakage preferably at a wider range of redshifts than what is currently available. In fact, since the only direct detections at z < 3 are the already mentioned galaxies Haro 11, and Tol 1247-232, this follow up study of Tol 1247-232 becomes increasingly important. Assuming that the underlying me ...
Lyman-alpha imaging of starburst galaxies in the local universe and beyond Matthew Hayes
... The universe is a large and poorly understood entity. A great deal of what we do understand comes from observations of the stars; by observing the radiation they produce directly, by observing reprocessed stellar energy, or by observing the violent phenomena in the final stages of stellar evolution. ...
... The universe is a large and poorly understood entity. A great deal of what we do understand comes from observations of the stars; by observing the radiation they produce directly, by observing reprocessed stellar energy, or by observing the violent phenomena in the final stages of stellar evolution. ...
ASTE Simultaneous HCN(4–3) and HCO+(4–3)
... to the ν 2 scaling (∼16), expected for fully-thermalized optically-thick gas (Riechers et al. 2006), supporting the presence of high-density, warm gas in NGC 4418. The HCO + (4–3) to HCO+ (1–0) flux ratio is <15. For Arp 220, the HCN(4–3) and HCO+ (4–3) flux ratio is estimated to be >3.0. The J = 4– ...
... to the ν 2 scaling (∼16), expected for fully-thermalized optically-thick gas (Riechers et al. 2006), supporting the presence of high-density, warm gas in NGC 4418. The HCO + (4–3) to HCO+ (1–0) flux ratio is <15. For Arp 220, the HCN(4–3) and HCO+ (4–3) flux ratio is estimated to be >3.0. The J = 4– ...
The Observer`s Guide to the Gamma-Ray Burst
... long-duration (and their various sub-classes) gamma-ray bursts (GRBs) and their accompanying supernovae (SNe). The analysis presented here is from the point of view of an observer, with much of the emphasis placed on how observations, and the modelling of observations, have constrained what we known ...
... long-duration (and their various sub-classes) gamma-ray bursts (GRBs) and their accompanying supernovae (SNe). The analysis presented here is from the point of view of an observer, with much of the emphasis placed on how observations, and the modelling of observations, have constrained what we known ...
A Multi-wavelength study on gamma
... Swift XRT afterglow (2) diverse physical origins of shallow decay phase of Swift XRT afterglow. (3) Jet break (in-)consistency in both X-Ray and Optical observations. Based on the Fermi observation data, I focused on the 17 GRBs with Fermi/LAT high-energy emission and found there are three elemental ...
... Swift XRT afterglow (2) diverse physical origins of shallow decay phase of Swift XRT afterglow. (3) Jet break (in-)consistency in both X-Ray and Optical observations. Based on the Fermi observation data, I focused on the 17 GRBs with Fermi/LAT high-energy emission and found there are three elemental ...
The 3-D shaping of NGC 6741: a massive, fast
... semi-axes, respectively), surrounded by a sharp low-excitation skin (the ionization front), and embedded into a spherical (radius≃0.080 pc), almost-neutral, high-density (n(H I) ≃7×103 atoms cm−3 ) halo containing a large fraction of the nebular mass (Mhalo ≥0.20 M⊙ ). The kinematics, physical condi ...
... semi-axes, respectively), surrounded by a sharp low-excitation skin (the ionization front), and embedded into a spherical (radius≃0.080 pc), almost-neutral, high-density (n(H I) ≃7×103 atoms cm−3 ) halo containing a large fraction of the nebular mass (Mhalo ≥0.20 M⊙ ). The kinematics, physical condi ...
this article
... The H fluxes and H equivalent widths presented in this paper include contributions from the two satellite [N ii] lines at 6548 and 6584 8. Complete inclusion of these lines in our line filters allows the possibility to later correct for [N ii] contamination when more information is available. Prev ...
... The H fluxes and H equivalent widths presented in this paper include contributions from the two satellite [N ii] lines at 6548 and 6584 8. Complete inclusion of these lines in our line filters allows the possibility to later correct for [N ii] contamination when more information is available. Prev ...
Post-Common-Envelope Binaries from the Sloan Digital Sky Survey
... I deeply thank Dr. Boris Gänsicke for his excellent guidance through my PhD, for his help and suggestions, and most importantly for making it possible for me to develop my qualities as a researcher. I am also deeply thankful for his trust in me in this and other projects. Without him this thesis wo ...
... I deeply thank Dr. Boris Gänsicke for his excellent guidance through my PhD, for his help and suggestions, and most importantly for making it possible for me to develop my qualities as a researcher. I am also deeply thankful for his trust in me in this and other projects. Without him this thesis wo ...
The 3-D shaping of NGC 6741: A massive, fast
... surrounded by a sharp low-excitation skin (the ionization front), and embedded in a spherical (radius 0.080 pc), almostneutral, high-density (n(H I) 7 × 103 atoms cm−3 ) halo containing a large fraction of the nebular mass (Mhalo ≥ 0.20 M ). The kinematics, physical conditions and ionic structu ...
... surrounded by a sharp low-excitation skin (the ionization front), and embedded in a spherical (radius 0.080 pc), almostneutral, high-density (n(H I) 7 × 103 atoms cm−3 ) halo containing a large fraction of the nebular mass (Mhalo ≥ 0.20 M ). The kinematics, physical conditions and ionic structu ...
Galaxies in the Universe: An Introduction, Second Edition
... Boldface is used for vectors; italics indicate concepts from physics, or specialist terms from astronomy which the reader will see again in this text, or will meet in the astronomical literature. Because they deal with large distances and long timescales, astronomers use an odd mixture of units, dep ...
... Boldface is used for vectors; italics indicate concepts from physics, or specialist terms from astronomy which the reader will see again in this text, or will meet in the astronomical literature. Because they deal with large distances and long timescales, astronomers use an odd mixture of units, dep ...
Galaxy Evolution Over the Past Eleven Billion Years: Mergers and
... Galaxy evolution studies have been revolutionized by the advent of near-infrared observations over the last decade. An intriguingly population of distant red galaxies, only visible at near-infrared wavelengths, was discovered. They were previously overlooked, since they are invisible even in the dee ...
... Galaxy evolution studies have been revolutionized by the advent of near-infrared observations over the last decade. An intriguingly population of distant red galaxies, only visible at near-infrared wavelengths, was discovered. They were previously overlooked, since they are invisible even in the dee ...
Galaxy morphology, luminosity, and environment in the SDSS DR7
... and blue) using data from the Sloan Digital Sky Survey (SDSS), correcting the luminosities for the intrinsic absorption. We use the global luminosity density field to define different environments, and analyse the environmental dependence of galaxy morphology and colour. The smoothed bootstrap method ...
... and blue) using data from the Sloan Digital Sky Survey (SDSS), correcting the luminosities for the intrinsic absorption. We use the global luminosity density field to define different environments, and analyse the environmental dependence of galaxy morphology and colour. The smoothed bootstrap method ...
arXiv:astro-ph/0702414v1 15 Feb 2007
... be less affected by dust than the continuum radiation in a twophase interstellar medium. Moreover, a large-scale outflow of neutral gas can decrease the number of Lyα resonance scattering (Kunth et al. 1998), if the neutral gas is velocity-shifted with respect to the ionised gas. To conclude, interp ...
... be less affected by dust than the continuum radiation in a twophase interstellar medium. Moreover, a large-scale outflow of neutral gas can decrease the number of Lyα resonance scattering (Kunth et al. 1998), if the neutral gas is velocity-shifted with respect to the ionised gas. To conclude, interp ...
Galaxy And Mass Assembly (GAMA): Gas Fuelling of Spiral Galaxies
... gives rise to a population of so-called satellite galaxies, i.e. galaxies which are bound to their host DMH but are not at rest with respect to its center of mass, having been captured during the merging of two smaller DMH. In the context of the flow of gas from the IHM into the ISM it is essential ...
... gives rise to a population of so-called satellite galaxies, i.e. galaxies which are bound to their host DMH but are not at rest with respect to its center of mass, having been captured during the merging of two smaller DMH. In the context of the flow of gas from the IHM into the ISM it is essential ...
Lya escape from z~ 0.03 star-forming galaxies: the dominant role of
... their escape from galaxies. These processes can only be observed in detail out to a few ×100 Mpc. Past nearby (z < 0.3) spectroscopic studies are based on small samples and/or kinematically unresolved data. Taking advantage of the high sensitivity of HST ’s COS, we observed the Lyα lines of 20 Hα-se ...
... their escape from galaxies. These processes can only be observed in detail out to a few ×100 Mpc. Past nearby (z < 0.3) spectroscopic studies are based on small samples and/or kinematically unresolved data. Taking advantage of the high sensitivity of HST ’s COS, we observed the Lyα lines of 20 Hα-se ...
Annual Report 2012
... CRIRES spectrograph at the VLT, it was possible to detect molecular absorption from CO at 2.3 micron in the dayside spectrum of this planet, and to measure the Doppler shift due to its motion along the orbit. This yielded the planet mass and the orbital inclination, which were unknown before. Recent ...
... CRIRES spectrograph at the VLT, it was possible to detect molecular absorption from CO at 2.3 micron in the dayside spectrum of this planet, and to measure the Doppler shift due to its motion along the orbit. This yielded the planet mass and the orbital inclination, which were unknown before. Recent ...
AGN host galaxies at redshift z ≈ 0.7: peculiar or not?
... Methods. Using images of non-AGN galaxies and stars we create synthetic AGN images to investigate the impact of an optical nucleus (typical for type-1 AGN) on the morphological analysis of AGN host galaxies. Galaxy morphologies are described using asymmetry index A, concentration index C, Gini coeff ...
... Methods. Using images of non-AGN galaxies and stars we create synthetic AGN images to investigate the impact of an optical nucleus (typical for type-1 AGN) on the morphological analysis of AGN host galaxies. Galaxy morphologies are described using asymmetry index A, concentration index C, Gini coeff ...
The Destruction of an Oort Cloud in a rich stellar cluster
... birth environment rich in stars. Several thousand stars were estimated to have been born before the Sun, thus providing the source for 26 Al and 60 Fe traced in chondritic meteorites. The dynamical fate of the Sun was not addressed, but it seems possible that the Sun stayed gravitationally bound to ...
... birth environment rich in stars. Several thousand stars were estimated to have been born before the Sun, thus providing the source for 26 Al and 60 Fe traced in chondritic meteorites. The dynamical fate of the Sun was not addressed, but it seems possible that the Sun stayed gravitationally bound to ...
The COMPLETE Survey of Outflows in Perseus
... the high velocity CO trace the surrounding molecular gas entrained by the protostellar wind and remains visible by collisional excitation for much more time than the shocked gas. This is why CO has mostly been used for studying the impact of outflows on the surrounding molecular cloud. However, the ...
... the high velocity CO trace the surrounding molecular gas entrained by the protostellar wind and remains visible by collisional excitation for much more time than the shocked gas. This is why CO has mostly been used for studying the impact of outflows on the surrounding molecular cloud. However, the ...
An extended main-sequence turn-off in the Small
... range at which the turn-offs appear in this diagram. The eMSTO of NGC 411 has not been noticed in the previous WFPC2 data from Rich et al. (2000), probably because of the much higher photometric errors at that time. In our observations, the photometric errors at the turn-off level (F475W∼21) are jus ...
... range at which the turn-offs appear in this diagram. The eMSTO of NGC 411 has not been noticed in the previous WFPC2 data from Rich et al. (2000), probably because of the much higher photometric errors at that time. In our observations, the photometric errors at the turn-off level (F475W∼21) are jus ...
Binary and Millisecond Pulsars | SpringerLink
... then this pulsar could be a very useful probe of the equation of state of super dense matter. While the hunt for more rapidly rotating pulsars and even “sub-millisecond pulsars” continues, and most neutron star equations of state allow higher spin rates than 716 Hz, it has been suggested [38] that t ...
... then this pulsar could be a very useful probe of the equation of state of super dense matter. While the hunt for more rapidly rotating pulsars and even “sub-millisecond pulsars” continues, and most neutron star equations of state allow higher spin rates than 716 Hz, it has been suggested [38] that t ...
Observational motivation for Dark Matter
... After transition to matter domination, T drops but Baryons and photons are still connected Due to abundance of photons, only when T~eV matter suddenly recombines Transfer from Thomson cross section to neutral Hydrogen makes the universe transparent to photons (but not to electrons!) Requires a full ...
... After transition to matter domination, T drops but Baryons and photons are still connected Due to abundance of photons, only when T~eV matter suddenly recombines Transfer from Thomson cross section to neutral Hydrogen makes the universe transparent to photons (but not to electrons!) Requires a full ...
Astrophysical X-ray source
Astrophysical X-ray sources are astronomical objects with physical properties which result in the emission of X-rays.There are a number of types of astrophysical objects which emit X-rays, from galaxy clusters, through black holes in active galactic nuclei (AGN) to galactic objects such as supernova remnants, stars, and binary stars containing a white dwarf (cataclysmic variable stars and super soft X-ray sources), neutron star or black hole (X-ray binaries). Some solar system bodies emit X-rays, the most notable being the Moon, although most of the X-ray brightness of the Moon arises from reflected solar X-rays. A combination of many unresolved X-ray sources is thought to produce the observed X-ray background. The X-ray continuum can arise from bremsstrahlung, either magnetic or ordinary Coulomb, black-body radiation, synchrotron radiation, inverse Compton scattering of lower-energy photons be relativistic electrons, knock-on collisions of fast protons with atomic electrons, and atomic recombination, with or without additional electron transitions.Furthermore, celestial entities in space are discussed as celestial X-ray sources. The origin of all observed astronomical X-ray sources is in, near to, or associated with a coronal cloud or gas at coronal cloud temperatures for however long or brief a period.