Effects of interaction on the properties of spiral galaxies. II. Isolated
... galaxies. The properties we have measured are compared with those of other analysis to find whether they are different. This contribution is organized as follows: The sample is briefly described in section 2. In section 3 we comment the morphological aspects. In section 4 we analyse the set of param ...
... galaxies. The properties we have measured are compared with those of other analysis to find whether they are different. This contribution is organized as follows: The sample is briefly described in section 2. In section 3 we comment the morphological aspects. In section 4 we analyse the set of param ...
Head–tail Galaxies: beacons of high
... wide-angle tailed galaxies (WATs) believed to be the result of ‘cluster weather’ (Klamer et al. 2004). NATs are most likely to be caused by the passage of the galaxy through the cluster (Odea & Owen 1985) while WATs are more likely to be associated with dominant cluster galaxies (Owen & Rudnick 1976 ...
... wide-angle tailed galaxies (WATs) believed to be the result of ‘cluster weather’ (Klamer et al. 2004). NATs are most likely to be caused by the passage of the galaxy through the cluster (Odea & Owen 1985) while WATs are more likely to be associated with dominant cluster galaxies (Owen & Rudnick 1976 ...
Predicting the CIB-φ contamination in the cross
... it cannot be completely removed from a tSZ Compton parameter map, which is constructed from a linear combination of multiple frequency maps. We have estimated the contamination of the CIB-φ correlation in the tSZ-φ power-spectrum. We considered linear combinations that reconstruct the tSZ Compton pa ...
... it cannot be completely removed from a tSZ Compton parameter map, which is constructed from a linear combination of multiple frequency maps. We have estimated the contamination of the CIB-φ correlation in the tSZ-φ power-spectrum. We considered linear combinations that reconstruct the tSZ Compton pa ...
Stellar Population Effects on the Inferred Photon Density at
... in astrophysics when a model for a stellar population is required. These combine theoretical (atmosphere and evolution) models or empirical spectra of individual stars, assuming some initial mass function (IMF) and stellar population age, and process the resultant emission through dust and gas scree ...
... in astrophysics when a model for a stellar population is required. These combine theoretical (atmosphere and evolution) models or empirical spectra of individual stars, assuming some initial mass function (IMF) and stellar population age, and process the resultant emission through dust and gas scree ...
Galaxy Pairs in the Sloan Digital Sky Survey
... We use a sample of close galaxy pairs selected from the Sloan Digital Sky Survey Data Release 4 (SDSS DR4) to investigate in what environments galaxy mergers occur and how the results of these mergers depend on differences in local galaxy density. The galaxies are quantified morphologically using tw ...
... We use a sample of close galaxy pairs selected from the Sloan Digital Sky Survey Data Release 4 (SDSS DR4) to investigate in what environments galaxy mergers occur and how the results of these mergers depend on differences in local galaxy density. The galaxies are quantified morphologically using tw ...
A deep view on the Virgo cluster core
... task (Jedrzejewski 1987) which is included in the STSDAS package of IRAF. All ellipse fits were performed with fixed parameters for center coordinates, position angle and ellipticity. In some cases like M86 and M87 better fitting results were obtained when variable ellipticity was applied. Obvious f ...
... task (Jedrzejewski 1987) which is included in the STSDAS package of IRAF. All ellipse fits were performed with fixed parameters for center coordinates, position angle and ellipticity. In some cases like M86 and M87 better fitting results were obtained when variable ellipticity was applied. Obvious f ...
Galaxy And Mass Assembly (GAMA): Understanding the wavelength
... shine a light on both their underlying stellar structure, and their possible formation mechanisms (e.g. Emsellem et al. 2011, and references therein). An alternative classification system is proposed in Graham (2014), and expanded upon in Graham et al. (submitted), in which both bulge-to-disc flux r ...
... shine a light on both their underlying stellar structure, and their possible formation mechanisms (e.g. Emsellem et al. 2011, and references therein). An alternative classification system is proposed in Graham (2014), and expanded upon in Graham et al. (submitted), in which both bulge-to-disc flux r ...
MUSE three-dimensional spectroscopy and kinematics of the
... indicate (e.g. O’Dea, Baum & Stanghellini 1991) that they have become confined (trapped) within the host galaxy nucleus by a very dense (clumpy and dusty) interstellar medium, or simply that they are observed very soon after the radio outburst is triggered (e.g. Morganti et al. 1997). It is now cons ...
... indicate (e.g. O’Dea, Baum & Stanghellini 1991) that they have become confined (trapped) within the host galaxy nucleus by a very dense (clumpy and dusty) interstellar medium, or simply that they are observed very soon after the radio outburst is triggered (e.g. Morganti et al. 1997). It is now cons ...
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; ...
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 ...
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).