matter and dark energy Gravitational lensing: a unique probe of dark
... multiple images of a distant source (a phenomenon now termed strong lensing) but, as its occurrence depends on the precise alignment of a source and deflector, it was reasonable to conclude that the probability of observing such phenomena would be very small. As a good illustration of thinking at th ...
... multiple images of a distant source (a phenomenon now termed strong lensing) but, as its occurrence depends on the precise alignment of a source and deflector, it was reasonable to conclude that the probability of observing such phenomena would be very small. As a good illustration of thinking at th ...
Power Point
... metallicity • Kuntschner 2000 - sample 22 early-type galaxies in Fornax cluster found lenticulars younger and similar metallicity • Jones et al. 1999 no difference ages ellipticals and lenticulars • Thomas & Kauffmann 1999 - luminous ellipticals are the last to form in the hierarchical merger model ...
... metallicity • Kuntschner 2000 - sample 22 early-type galaxies in Fornax cluster found lenticulars younger and similar metallicity • Jones et al. 1999 no difference ages ellipticals and lenticulars • Thomas & Kauffmann 1999 - luminous ellipticals are the last to form in the hierarchical merger model ...
- Max-Planck-Institut für Astronomie
... Morphology and SEDs) survey in conjunction with the COMBO-17 photometric redshift survey to constrain the incidence of major mergers between spheroid-dominated galaxies with little cold gas (dry mergers) since z ¼ 0:7. A set of N-body merger simulations was used to explore the morphological signatur ...
... Morphology and SEDs) survey in conjunction with the COMBO-17 photometric redshift survey to constrain the incidence of major mergers between spheroid-dominated galaxies with little cold gas (dry mergers) since z ¼ 0:7. A set of N-body merger simulations was used to explore the morphological signatur ...
Environment and self-regulation in galaxy formation
... should be less than the value χ2 obtained in the fit. If P > 0.999 we deem the fit unacceptable. In this case we discard the index with the largest χ2 from the fitting procedure, re-do the fit, and re-calculate P . This procedure is iterated until P < 0.999. The indices Ca4455 and NaD were discarded ...
... should be less than the value χ2 obtained in the fit. If P > 0.999 we deem the fit unacceptable. In this case we discard the index with the largest χ2 from the fitting procedure, re-do the fit, and re-calculate P . This procedure is iterated until P < 0.999. The indices Ca4455 and NaD were discarded ...
Dark matter distribution and indirect detection in dwarf spheroidal
... Application to 22 (classical and ultrafaint) dSph galaxies → J-factors (annihilation and decay) with robust error bars → Ursa Minor and Draco are the best 'safe' targets → Coma and Ursa Major 2 are more uncertain but possibly more promising → Segue 1 is very uncertain – possible stellar contaminatio ...
... Application to 22 (classical and ultrafaint) dSph galaxies → J-factors (annihilation and decay) with robust error bars → Ursa Minor and Draco are the best 'safe' targets → Coma and Ursa Major 2 are more uncertain but possibly more promising → Segue 1 is very uncertain – possible stellar contaminatio ...
Chapter 1
... ratios are higher than a cooler nebula. This is because to produce [O iii] λ4363 an electron needs to be excited to 5.3 eV, which requires more energy than for 4959/5007 which result from decay from 1 D2 level, 2.5 eV above the ground-state (see Figure 2.2). Therefore, these ratios can be used to co ...
... ratios are higher than a cooler nebula. This is because to produce [O iii] λ4363 an electron needs to be excited to 5.3 eV, which requires more energy than for 4959/5007 which result from decay from 1 D2 level, 2.5 eV above the ground-state (see Figure 2.2). Therefore, these ratios can be used to co ...
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 ...
galaxy formation with cold gas accretion and evolving stellar initial
... naive speculation although its exact form is far from clear. There is theoretical and observational evidence for the stellar IMF at high z to be top-heavy or bottom-light (e.g., Larson 2005; van Dokkum 2008). Constraints on the stellar IMF can also be obtained from comparisons between the evolution ...
... naive speculation although its exact form is far from clear. There is theoretical and observational evidence for the stellar IMF at high z to be top-heavy or bottom-light (e.g., Larson 2005; van Dokkum 2008). Constraints on the stellar IMF can also be obtained from comparisons between the evolution ...
GRB prompt emission
... • As we learned yesterday, afterglows allowed us to calculate redshifts. • Assuming a cosmology, we can then get distances. • Assuming isotropic explosions, we can estimate the GRB energies! These energies range over many orders of magnitude. • But are GRBs isotropic? ...
... • As we learned yesterday, afterglows allowed us to calculate redshifts. • Assuming a cosmology, we can then get distances. • Assuming isotropic explosions, we can estimate the GRB energies! These energies range over many orders of magnitude. • But are GRBs isotropic? ...
Lecture 3
... • As well as problems from intermediate z galaxies, also have problems with cool stars • M, L and T-class stars are very red in the same bands as z=5 and z=6 LBGs • Can identify stars with HST data (morphology), or very deep infrared data (colour) • Problem if the survey is ground based or objects a ...
... • As well as problems from intermediate z galaxies, also have problems with cool stars • M, L and T-class stars are very red in the same bands as z=5 and z=6 LBGs • Can identify stars with HST data (morphology), or very deep infrared data (colour) • Problem if the survey is ground based or objects a ...
SimulationDatabases
... Find all the z=3 progenitors of z=0 red ellipticals (i.e. B-V>0.8 B/T > 0.5) Find the descendents at z=1 of all LBG's (i.e. galaxies with SFR>10 Msun/yr) at z=3 Find all the z=2 galaxies which were within 1Mpc of a LBG (i.e. SFR>10Msun/yr) at some previous redshift. Find the multiplicity function of ...
... Find all the z=3 progenitors of z=0 red ellipticals (i.e. B-V>0.8 B/T > 0.5) Find the descendents at z=1 of all LBG's (i.e. galaxies with SFR>10 Msun/yr) at z=3 Find all the z=2 galaxies which were within 1Mpc of a LBG (i.e. SFR>10Msun/yr) at some previous redshift. Find the multiplicity function of ...
DEDUCING THE LIFETIME OF SHORT GAMMA
... can be estimated from well-defined samples of galaxies. Galaxy MFs have been measured based on a few large galaxy redshift surveys (e.g., Kauffmann et al. 2003; Bell et al. 2003). For the calculations presented here, we adopt the galaxy MF measured by Bell et al. (2003) using a large sample of galax ...
... can be estimated from well-defined samples of galaxies. Galaxy MFs have been measured based on a few large galaxy redshift surveys (e.g., Kauffmann et al. 2003; Bell et al. 2003). For the calculations presented here, we adopt the galaxy MF measured by Bell et al. (2003) using a large sample of galax ...
A Deeper Look at Faint H $\ alpha $ Emission in Nearby Dwarf
... observed (i.e., no extinction corrections applied) Hα luminosity of these regions range from 5×1035 ergs s−1 to 2×1036 ergs s−1 , which corresponds to the ionizing fluxes of single B0V-O9V stars (Smith et al. 2002), assuming Case B recombination and that the HII regions are radiation bounded. If the ...
... observed (i.e., no extinction corrections applied) Hα luminosity of these regions range from 5×1035 ergs s−1 to 2×1036 ergs s−1 , which corresponds to the ionizing fluxes of single B0V-O9V stars (Smith et al. 2002), assuming Case B recombination and that the HII regions are radiation bounded. If the ...
Homogeneity and isotropy in the 2MASS Photometric Redshift
... for all the galaxies is necessary, and therefore these methods have only been used on spectroscopic catalogues, which traditionally cover much smaller volumes than their photometric counterparts. As we however showed in a previous publication (Alonso et al. 2014), it is possible to adapt this kind o ...
... for all the galaxies is necessary, and therefore these methods have only been used on spectroscopic catalogues, which traditionally cover much smaller volumes than their photometric counterparts. As we however showed in a previous publication (Alonso et al. 2014), it is possible to adapt this kind o ...
Dark matter
... According to the Big Bang model, the universe expanded from an extremely dense and hot state and continues to expand today. A common and useful analogy explains that space itself is expanding, carrying galaxies with it, like raisins in a rising loaf of bread. General relativistic cosmologies, howeve ...
... According to the Big Bang model, the universe expanded from an extremely dense and hot state and continues to expand today. A common and useful analogy explains that space itself is expanding, carrying galaxies with it, like raisins in a rising loaf of bread. General relativistic cosmologies, howeve ...
My talk on CO at z=0 from Santiago in June, 2011
... #8. CO-to-H2 is a Multi-Parameter Problem Hydrogen is H2 Carbon is CII, little/no CO Size depends on dust shielding Dust depends on metallicity. ...
... #8. CO-to-H2 is a Multi-Parameter Problem Hydrogen is H2 Carbon is CII, little/no CO Size depends on dust shielding Dust depends on metallicity. ...
The MUSIC of galaxy clusters – I. Baryon properties and scaling
... MultiDark (MD) simulation. We selected all the clusters using criteria based on mass (selecting all the clusters having a total mass larger than 1015 h−1 M ) or on morphology (selecting groups of clusters corresponding to different morphology classes, bullet-like clusters and relaxed clusters). All ...
... MultiDark (MD) simulation. We selected all the clusters using criteria based on mass (selecting all the clusters having a total mass larger than 1015 h−1 M ) or on morphology (selecting groups of clusters corresponding to different morphology classes, bullet-like clusters and relaxed clusters). All ...
and galaxies
... together to make ‘grains’. When this region heats up again, the increased radiation pressure from the star pushes these out of the star’s atmosphere and into space. 2GLSS P.H. Regan ...
... together to make ‘grains’. When this region heats up again, the increased radiation pressure from the star pushes these out of the star’s atmosphere and into space. 2GLSS P.H. Regan ...
Redshift
In physics, redshift happens when light or other electromagnetic radiation from an object is increased in wavelength, or shifted to the red end of the spectrum. In general, whether or not the radiation is within the visible spectrum, ""redder"" means an increase in wavelength – equivalent to a lower frequency and a lower photon energy, in accordance with, respectively, the wave and quantum theories of light.Some redshifts are an example of the Doppler effect, familiar in the change of apparent pitches of sirens and frequency of the sound waves emitted by speeding vehicles. A redshift occurs whenever a light source moves away from an observer. Another kind of redshift is cosmological redshift, which is due to the expansion of the universe, and sufficiently distant light sources (generally more than a few million light years away) show redshift corresponding to the rate of increase in their distance from Earth. Finally, gravitational redshift is a relativistic effect observed in electromagnetic radiation moving out of gravitational fields. Conversely, a decrease in wavelength is called blueshift and is generally seen when a light-emitting object moves toward an observer or when electromagnetic radiation moves into a gravitational field. However, redshift is a more common term and sometimes blueshift is referred to as negative redshift.Knowledge of redshifts and blueshifts has been applied to develop several terrestrial technologies such as Doppler radar and radar guns. Redshifts are also seen in the spectroscopic observations of astronomical objects. Its value is represented by the letter z.A special relativistic redshift formula (and its classical approximation) can be used to calculate the redshift of a nearby object when spacetime is flat. However, in many contexts, such as black holes and Big Bang cosmology, redshifts must be calculated using general relativity. Special relativistic, gravitational, and cosmological redshifts can be understood under the umbrella of frame transformation laws. There exist other physical processes that can lead to a shift in the frequency of electromagnetic radiation, including scattering and optical effects; however, the resulting changes are distinguishable from true redshift and are not generally referred to as such (see section on physical optics and radiative transfer).