1. INTRODUCTION 2. MASS AND LIGHT
... D3¡ to account for the observed events). This possibility could only apply to a self-gravitating structure and not to an intrinsically extended one such as tidal debris. 3. The argument of ° 2 fails because the intervening material is smooth on scales of D15¡ in both directions, the size of de Vauco ...
... D3¡ to account for the observed events). This possibility could only apply to a self-gravitating structure and not to an intrinsically extended one such as tidal debris. 3. The argument of ° 2 fails because the intervening material is smooth on scales of D15¡ in both directions, the size of de Vauco ...
The nature of extremely red galaxies in the local universe
... We investigate the nature of extremely red galaxies (ERGs), objects whose colours are redder than those found in the red sequence present in colour–magnitude diagrams of galaxies. We selected from the Sloan Digital Sky Survey Data Release 7 a volume-limited sample of such galaxies in the redshift in ...
... We investigate the nature of extremely red galaxies (ERGs), objects whose colours are redder than those found in the red sequence present in colour–magnitude diagrams of galaxies. We selected from the Sloan Digital Sky Survey Data Release 7 a volume-limited sample of such galaxies in the redshift in ...
CONSTRAINTS ON THE VERY HIGH ENERGY
... extends above 1300 GeV, cascading overproduces the background by a factor of 10.25: either AGNs as a whole cannot make up the background, or they are weak VHE sources. A more likely background candidate is the blazar subclass of AGNs, which does show strong GeV emission. This emission can be rapidly ...
... extends above 1300 GeV, cascading overproduces the background by a factor of 10.25: either AGNs as a whole cannot make up the background, or they are weak VHE sources. A more likely background candidate is the blazar subclass of AGNs, which does show strong GeV emission. This emission can be rapidly ...
Gravitationally lensed galaxies at 2 z 3.5: direct abundance
... with decreasing metallicity; however, low-metallicity galaxies at high redshift are also very faint, so the line is difficult to detect, in particular since the line is redshifted to near-infrared (IR) part of the spectrum. The high-redshift LBGs with <25.5 mag (Steidel et al. 1996) are known to be ...
... with decreasing metallicity; however, low-metallicity galaxies at high redshift are also very faint, so the line is difficult to detect, in particular since the line is redshifted to near-infrared (IR) part of the spectrum. The high-redshift LBGs with <25.5 mag (Steidel et al. 1996) are known to be ...
A dozen new galaxies caught in the act: Gas stripping and extended
... designed for observing Hα emitting objects in the Coma cluster at z=0.0225, and has bell-shaped transmission with a central wavelength of 6712 Å and FWHM of 120 Å (Yagi et al. 2007; ...
... designed for observing Hα emitting objects in the Coma cluster at z=0.0225, and has bell-shaped transmission with a central wavelength of 6712 Å and FWHM of 120 Å (Yagi et al. 2007; ...
Lecture 16, AGN Evolution
... XMM-Newton also observes at these high energies: poorer angular resolution than Chandra, but larger telescope collecting area ...
... XMM-Newton also observes at these high energies: poorer angular resolution than Chandra, but larger telescope collecting area ...
ISR_hst2galign - Space Telescope Science Institute
... means that special care must be made in constructing models to describe how the light of point sources is distributed. A single exposure cannot tell us how concentrated the PSF is (see Figure 1 in Anderson & King 2000), so we must combine multiple dithered exposures if we hope to construct an accura ...
... means that special care must be made in constructing models to describe how the light of point sources is distributed. A single exposure cannot tell us how concentrated the PSF is (see Figure 1 in Anderson & King 2000), so we must combine multiple dithered exposures if we hope to construct an accura ...
PDF only - at www.arxiv.org.
... Trumpler (1930) defined star clusters as ‘Star groupings which undoubtedly form physical systems (stars situated at the same distance and probably of the same origin) and which at the same time are sufficiently rich in stars for statistical investigation.’ Majority of the stars in the Galaxy are bel ...
... Trumpler (1930) defined star clusters as ‘Star groupings which undoubtedly form physical systems (stars situated at the same distance and probably of the same origin) and which at the same time are sufficiently rich in stars for statistical investigation.’ Majority of the stars in the Galaxy are bel ...
Article PDF - IOPscience
... galaxies in the central region of the Coma cluster. They reside near the red- and blueshifted edges of the radial velocity distribution of Coma cluster member galaxies. Our findings suggest that most of the parent galaxies were recently captured by the Coma cluster potential and are now infalling to ...
... galaxies in the central region of the Coma cluster. They reside near the red- and blueshifted edges of the radial velocity distribution of Coma cluster member galaxies. Our findings suggest that most of the parent galaxies were recently captured by the Coma cluster potential and are now infalling to ...
On the origin of lopsidedness in galaxies as determined
... into a “nature” category, for example, one in which the lopsidedness arises from an asymmetric dark matter dominated potential, and a “nurture” category, for example, one in which the lopsidedness arises directly from interactions or mergers with another galaxy. Disentangling the scenarios, if at al ...
... into a “nature” category, for example, one in which the lopsidedness arises from an asymmetric dark matter dominated potential, and a “nurture” category, for example, one in which the lopsidedness arises directly from interactions or mergers with another galaxy. Disentangling the scenarios, if at al ...
A 6% measurement of the Hubble parameter at ζ ∼ 0.45: direct
... and accurate cosmic chronometers using passively evolving selected galaxies. Recently, the independent analysis of SDSS-DR8 luminous red galaxies by ref. [33] has confirmed that massive and quiescent galaxies can be reliably used as cosmic chronometers. It is important to underline that the main str ...
... and accurate cosmic chronometers using passively evolving selected galaxies. Recently, the independent analysis of SDSS-DR8 luminous red galaxies by ref. [33] has confirmed that massive and quiescent galaxies can be reliably used as cosmic chronometers. It is important to underline that the main str ...
The role of black holes in galaxy formation and evolution
... winds in two ways. They can heat the gas and cause it to expand (thermal “energy-driven” winds) or they can push it out (pressure “momentum-driven” winds). Photons heat the gas by photoionising metals such as iron, which retain their inner electrons even at high temperature, and by Compton scatteri ...
... winds in two ways. They can heat the gas and cause it to expand (thermal “energy-driven” winds) or they can push it out (pressure “momentum-driven” winds). Photons heat the gas by photoionising metals such as iron, which retain their inner electrons even at high temperature, and by Compton scatteri ...
The SAMI Pilot Survey: The Fundamental and Mass Planes in Three
... (by 22 per cent) and higher dispersion (by 13 per cent) at fixed luminosity, though the mean offsets in both size and dispersion are within the scatter of the distributions. ...
... (by 22 per cent) and higher dispersion (by 13 per cent) at fixed luminosity, though the mean offsets in both size and dispersion are within the scatter of the distributions. ...
Weak gravitational lensing
While the presence of any mass bends the path of light passing near it, this effect rarely produces the giant arcs and multiple images associated with strong gravitational lensing. Most lines of sight in the universe are thoroughly in the weak lensing regime, in which the deflection is impossible to detect in a single background source. However, even in these cases, the presence of the foreground mass can be detected, by way of a systematic alignment of background sources around the lensing mass. Weak gravitational lensing is thus an intrinsically statistical measurement, but it provides a way to measure the masses of astronomical objects without requiring assumptions about their composition or dynamical state.