Morphology and dynamics of the cosmic web Aragón Calvo
... filament. This effect disagrees with our findings from N-body simulations. A trend can be appreciated for a dependence on both color and luminosity. Blue galaxies are more oriented than red ones and more luminous galaxies (Mr ≥ 19) are more strongly oriented. Unfortunately, the limited size of our s ...
... filament. This effect disagrees with our findings from N-body simulations. A trend can be appreciated for a dependence on both color and luminosity. Blue galaxies are more oriented than red ones and more luminous galaxies (Mr ≥ 19) are more strongly oriented. Unfortunately, the limited size of our s ...
APS Neutrino Study
... of the primordial abundances of deuterium, helium and lithium will improve the precision of BBN, testing both the standard model of particle physics and the framework of standard cosmology. Though less sensitive now, the CMB constraint on the number of neutrino flavors is expected to markedly improv ...
... of the primordial abundances of deuterium, helium and lithium will improve the precision of BBN, testing both the standard model of particle physics and the framework of standard cosmology. Though less sensitive now, the CMB constraint on the number of neutrino flavors is expected to markedly improv ...
Dark Energy from the Gas of Wormholes
... contribution of wormholes to dark matter and dark energy we find estimates for characteristic parameters of the gas of wormholes. ...
... contribution of wormholes to dark matter and dark energy we find estimates for characteristic parameters of the gas of wormholes. ...
The XXL Survey - I. Scientific motivations − XMM
... the cluster’s apparent size and the extent_likelihood parameter is a function of cluster size and flux that depends on the local XMM sensitivity. Extensive simulations enable the definition of limits for extent and extent_likelihood above which contamination from point-sources is negligible. Relaxin ...
... the cluster’s apparent size and the extent_likelihood parameter is a function of cluster size and flux that depends on the local XMM sensitivity. Extensive simulations enable the definition of limits for extent and extent_likelihood above which contamination from point-sources is negligible. Relaxin ...
THE GREAT AGN DEBATE `AGN VS STARBURST
... versions of Seyfert Type 1 galaxy. They show strong optical continuum emission, Xray continuum emission, and broad and narrow optical emission lines. Some astronomers use the term QSO for this object reserving 'quasar' for radio-loud objects, while others use the terminology radio-quiet and radio-lo ...
... versions of Seyfert Type 1 galaxy. They show strong optical continuum emission, Xray continuum emission, and broad and narrow optical emission lines. Some astronomers use the term QSO for this object reserving 'quasar' for radio-loud objects, while others use the terminology radio-quiet and radio-lo ...
Lecture 3
... – similar Lyline distribution at z~5 – stronger Lya lines at z~6 • Very blue rest-UV spectra are hinting at changes in the nature of star formation • LBGs at every redshift are used to characterise evolution in star formation density and the mechanisms and environment for star formation • But, as ...
... – similar Lyline distribution at z~5 – stronger Lya lines at z~6 • Very blue rest-UV spectra are hinting at changes in the nature of star formation • LBGs at every redshift are used to characterise evolution in star formation density and the mechanisms and environment for star formation • But, as ...
Extragalactic background light inferred from AEGIS
... details of the model used in calculating the bolometric luminosity history of the universe and comparison with data and GSPD10 focuses on the derived EBL and γ -ray attenuation. The SGPD10– GSPD10 model is based on an updated version of the semi-analytic theoretical approach described in Somerville ...
... details of the model used in calculating the bolometric luminosity history of the universe and comparison with data and GSPD10 focuses on the derived EBL and γ -ray attenuation. The SGPD10– GSPD10 model is based on an updated version of the semi-analytic theoretical approach described in Somerville ...
Astrophysical Quark Matter
... QM in pulsar-like compact stars It is still a challenge for astrophysicists to reproduce a successful core-collapse supernova! ...
... QM in pulsar-like compact stars It is still a challenge for astrophysicists to reproduce a successful core-collapse supernova! ...
Dynamics of dark energy
... Refs. [11, 12]) which invoke an evolving canonical scalar field with a potential (effectively providing an inflaton for today) and makes use of the scaling properties [13, 14] and tracker nature [15, 16] of such scalar fields evolving in the presence of other background matter fields; scalar field m ...
... Refs. [11, 12]) which invoke an evolving canonical scalar field with a potential (effectively providing an inflaton for today) and makes use of the scaling properties [13, 14] and tracker nature [15, 16] of such scalar fields evolving in the presence of other background matter fields; scalar field m ...
Book of Abstracts - University of Sheffield
... 30 kg x yr, corresponding to the data acquired between February 28th, 2011 and March 31st, 2012. We lowered the energy threshold for detection to 0.7 keV for nuclear recoils using only the ionisation signal, searching for dark matter induced nuclear recoils in the energy interval between 0.7 keV and ...
... 30 kg x yr, corresponding to the data acquired between February 28th, 2011 and March 31st, 2012. We lowered the energy threshold for detection to 0.7 keV for nuclear recoils using only the ionisation signal, searching for dark matter induced nuclear recoils in the energy interval between 0.7 keV and ...
Universe of Motion - Reciprocal System of theory
... The availability of this accurate new physical theory, developed and verified in other fields where the facts are more readily accessible, now gives us a source of information about astronomical matters that is not subject to the limitations that are inherent in the procedures that the astronomers m ...
... The availability of this accurate new physical theory, developed and verified in other fields where the facts are more readily accessible, now gives us a source of information about astronomical matters that is not subject to the limitations that are inherent in the procedures that the astronomers m ...
Small glitches: the role of strange nuggets?
... dependent. On the other hand, the properties of SNs could be constrained by astrophysics, if they do exist in the Universe. As proposed by Witten, SNs could be a kind of dark matter candidate (Witten 1984). Although being baryonic matter, SNs could behave like dark matter because of the very low cha ...
... dependent. On the other hand, the properties of SNs could be constrained by astrophysics, if they do exist in the Universe. As proposed by Witten, SNs could be a kind of dark matter candidate (Witten 1984). Although being baryonic matter, SNs could behave like dark matter because of the very low cha ...
Effective Operators for Dark Matter Detection
... problem, i.e. to avoid fine-tuning of its couplings and provide a ‘natural’ explanation for its light mass. It is important to notice that this is an aesthetic criterion rather than a physical one, and that the Standard Model is perfectly consistent as it is now, even though the values of its coupli ...
... problem, i.e. to avoid fine-tuning of its couplings and provide a ‘natural’ explanation for its light mass. It is important to notice that this is an aesthetic criterion rather than a physical one, and that the Standard Model is perfectly consistent as it is now, even though the values of its coupli ...
some UNANSWERED QUESTIONS IN PHYSICS
... and other interactions and matter particles, are only valid in 10 dimensions (dimensions other than 3 that we see can be very small or very large) or in 26 dimensions if no supersymmetry ...
... and other interactions and matter particles, are only valid in 10 dimensions (dimensions other than 3 that we see can be very small or very large) or in 26 dimensions if no supersymmetry ...
A UV study of nearby luminous infrared galaxies: star formation
... We employ UV and optical photometry, from the GALEX and SDSS surveys respectively, to study the star formation histories (SFHs) of 561 luminous infrared galaxies (LIR > 1011 L⊙ ) in the nearby (z < 0.2) Universe. Visual inspection of a subsample of galaxies with r < 16.8 and z < 0.1 (for which eyeba ...
... We employ UV and optical photometry, from the GALEX and SDSS surveys respectively, to study the star formation histories (SFHs) of 561 luminous infrared galaxies (LIR > 1011 L⊙ ) in the nearby (z < 0.2) Universe. Visual inspection of a subsample of galaxies with r < 16.8 and z < 0.1 (for which eyeba ...
Annual Report 2014 - Max Planck Institute for Astrophysics
... particles, and the calculation of transition probThe Max-Planck-Institut für Astrophysik, usually abilities and cross–sections for astrophysical procalled MPA for short, was founded in 1958 under cesses in rarefied media. From its inception the the directorship of Ludwig Biermann. It was estab- MPA h ...
... particles, and the calculation of transition probThe Max-Planck-Institut für Astrophysik, usually abilities and cross–sections for astrophysical procalled MPA for short, was founded in 1958 under cesses in rarefied media. From its inception the the directorship of Ludwig Biermann. It was estab- MPA h ...
Studies of dark matter in and around stars
... was that the mass distribution does not follow the gas distribution as would be expected in a world without dark matter [5]. In contrast to galactic rotation curves, this is very difficult to explain by modifying gravity, since one has to dislocate the gravitational impact from the source. To explai ...
... was that the mass distribution does not follow the gas distribution as would be expected in a world without dark matter [5]. In contrast to galactic rotation curves, this is very difficult to explain by modifying gravity, since one has to dislocate the gravitational impact from the source. To explai ...
A New Model without Dark Matter for the Rotation of Spiral Galaxies
... M ario Everaldo de Souza: A New M odel without Dark M atter for the Rotation of Spiral Galaxies: the Connections among Shape, Kinematics and Evolution ...
... M ario Everaldo de Souza: A New M odel without Dark M atter for the Rotation of Spiral Galaxies: the Connections among Shape, Kinematics and Evolution ...
DEDUCING THE LIFETIME OF SHORT GAMMA
... host galaxies of short GRBs found so far are associated with old and massive galaxies with little current or recent star formation, which makes it unlikely that short bursts are associated with massive stars. Presently available data suggests, but not yet prove, a long time delay between the formati ...
... host galaxies of short GRBs found so far are associated with old and massive galaxies with little current or recent star formation, which makes it unlikely that short bursts are associated with massive stars. Presently available data suggests, but not yet prove, a long time delay between the formati ...
Galaxies: Interactions and Mergers Encyclopedia of Astronomy & Astrophysics eaa.iop.org C Mihos
... represented by N discrete particles whose initial positions and velocities sample the phase space distribution of a normal disk galaxy. Current simulations employ 106 –107 particles, so that each particle represents 104 –105 stars (simulating galaxies star by star is still well beyond current comput ...
... represented by N discrete particles whose initial positions and velocities sample the phase space distribution of a normal disk galaxy. Current simulations employ 106 –107 particles, so that each particle represents 104 –105 stars (simulating galaxies star by star is still well beyond current comput ...
The Distribution, Classification, and Color Evolution of Galaxies
... Figure 2.16: Histogram of Galaxy Populations. Ellipticals, starforming, and non-starforming spirals have different population distributions for different SDSS colors ....................................................................... 19 Figure 4.1: Number Fraction-Redshift Relation of Galaxies . ...
... Figure 2.16: Histogram of Galaxy Populations. Ellipticals, starforming, and non-starforming spirals have different population distributions for different SDSS colors ....................................................................... 19 Figure 4.1: Number Fraction-Redshift Relation of Galaxies . ...
original version
... Galaxy-galaxy interactions and mergers are an important factor in the dominant cosmological model of galaxy evolution, in which mergers between dark matter haloes and/or luminous galaxies occur frequently, increasing their mass and ultimately shaping them into the galaxies that we observe at the cur ...
... Galaxy-galaxy interactions and mergers are an important factor in the dominant cosmological model of galaxy evolution, in which mergers between dark matter haloes and/or luminous galaxies occur frequently, increasing their mass and ultimately shaping them into the galaxies that we observe at the cur ...
The colour–magnitude relation of early
... redder, early-type galaxies will be robust to this type of error, but we bear in mind that the redshifts of the fainter, blue galaxies in our sample may be susceptible to this source of error. Our code also gives an estimate of the photometric bulge-to-total light (B/T) ratio (see below) as well as ...
... redder, early-type galaxies will be robust to this type of error, but we bear in mind that the redshifts of the fainter, blue galaxies in our sample may be susceptible to this source of error. Our code also gives an estimate of the photometric bulge-to-total light (B/T) ratio (see below) as well as ...
The Cosmological Constant Problem, an Inspiration for New Physics
... problem, which is at the edge of elementary particle physics and cosmology. This problem is deeply connected with the difficulties formulating a theory of quantum gravity. After the 1998 discovery that our universe’s expansion is accelerating, the cosmological constant problem has obtained a new dim ...
... problem, which is at the edge of elementary particle physics and cosmology. This problem is deeply connected with the difficulties formulating a theory of quantum gravity. After the 1998 discovery that our universe’s expansion is accelerating, the cosmological constant problem has obtained a new dim ...
Evolution of high-redshift quasars
... and emission line strengths. On the blue side of Lyα emission, the strong IGM absorption at z ∼ 6 removes most of the quasar flux. Adapted from Fan et al. (2004) z ∼ 6 quasars are indicative of supersolar metallicity in these systems. Freudling et al. (2003) and Barth et al. (2003). detected strong ...
... and emission line strengths. On the blue side of Lyα emission, the strong IGM absorption at z ∼ 6 removes most of the quasar flux. Adapted from Fan et al. (2004) z ∼ 6 quasars are indicative of supersolar metallicity in these systems. Freudling et al. (2003) and Barth et al. (2003). detected strong ...
Big Bang
The Big Bang theory is the prevailing cosmological model for the universe from the earliest known periods through its subsequent large-scale evolution. The model accounts for the fact that the universe expanded from a very high density and high temperature state, and offers a comprehensive explanation for a broad range of observed phenomena, including the abundance of light elements, the cosmic microwave background, large scale structure, and Hubble's Law. If the known laws of physics are extrapolated beyond where they are valid, there is a singularity. Modern measurements place this moment at approximately 13.8 billion years ago, which is thus considered the age of the universe. After the initial expansion, the universe cooled sufficiently to allow the formation of subatomic particles, and later simple atoms. Giant clouds of these primordial elements later coalesced through gravity to form stars and galaxies.Since Georges Lemaître first noted, in 1927, that an expanding universe might be traced back in time to an originating single point, scientists have built on his idea of cosmic expansion. While the scientific community was once divided between supporters of two different expanding universe theories, the Big Bang and the Steady State theory, accumulated empirical evidence provides strong support for the former. In 1929, from analysis of galactic redshifts, Edwin Hubble concluded that galaxies are drifting apart, important observational evidence consistent with the hypothesis of an expanding universe. In 1965, the cosmic microwave background radiation was discovered, which was crucial evidence in favor of the Big Bang model, since that theory predicted the existence of background radiation throughout the universe before it was discovered. More recently, measurements of the redshifts of supernovae indicate that the expansion of the universe is accelerating, an observation attributed to dark energy's existence. The known physical laws of nature can be used to calculate the characteristics of the universe in detail back in time to an initial state of extreme density and temperature.