AN ULTRA-DEEP NEAR-INFRARED SPECTRUM OF
... The galaxy was observed in a cross-dispersed mode, in combination with the 32 lines mm−1 grating and the 0. 675 slit. The spectral resolution varies between ∼ 900 and ∼ 1050 over the different orders. Observations were done using an ABA B on-source dither pattern, such that we can use the averag ...
... The galaxy was observed in a cross-dispersed mode, in combination with the 32 lines mm−1 grating and the 0. 675 slit. The spectral resolution varies between ∼ 900 and ∼ 1050 over the different orders. Observations were done using an ABA B on-source dither pattern, such that we can use the averag ...
Sunyaev±Zel'dovich distortion from early galactic winds Subhabrata Majumdar, Biman B. Nath
... This is what we calculate in this paper. In addition, we take into account the kinetic Sunyaev±Zel'dovich (SZ) effect and the effect of clustering of parent galaxies. The importance of the kinetic SZ (kSZ) effect of outflows ± in the case of quasar outflows ± has already been shown by Natarajan, Sig ...
... This is what we calculate in this paper. In addition, we take into account the kinetic Sunyaev±Zel'dovich (SZ) effect and the effect of clustering of parent galaxies. The importance of the kinetic SZ (kSZ) effect of outflows ± in the case of quasar outflows ± has already been shown by Natarajan, Sig ...
Lec16_2D
... If there were no mass (i.e., no gravity) in the universe, the Hubble expansion would proceed at a constant speed. The age of the universe would then just be given by 1 / H0. In a real universe with mass, gravity must have (over time) slowed the Hubble expansion. In the past, the galaxies must have b ...
... If there were no mass (i.e., no gravity) in the universe, the Hubble expansion would proceed at a constant speed. The age of the universe would then just be given by 1 / H0. In a real universe with mass, gravity must have (over time) slowed the Hubble expansion. In the past, the galaxies must have b ...
Universe 8e Lecture Chapter 24 Galaxies
... The Hubble Law: There is a simple linear relationship between the distance from the Earth to a remote galaxy and the redshift of that galaxy (which is a measure of the speed with which it is receding from us). This relationship is the Hubble law, v = H0d. The value of the Hubble constant, H0, is not ...
... The Hubble Law: There is a simple linear relationship between the distance from the Earth to a remote galaxy and the redshift of that galaxy (which is a measure of the speed with which it is receding from us). This relationship is the Hubble law, v = H0d. The value of the Hubble constant, H0, is not ...
Sample Exam for Final (with correct answers)
... (e) We know the times of giant explosions in these galaxies, then measure the time the light signals arrive at Earth. 23. The physical significance of the Hubble Constant is that it (a) corresponds to the time since the universe began to expand. ∗ (b) gives the total mass of the universe. (c) repres ...
... (e) We know the times of giant explosions in these galaxies, then measure the time the light signals arrive at Earth. 23. The physical significance of the Hubble Constant is that it (a) corresponds to the time since the universe began to expand. ∗ (b) gives the total mass of the universe. (c) repres ...
The Transient Radio Sky Astrophysical and Artificial
... •Standard (comoving) rod, S, fixed by sound horizon (acoustic oscillations) at recombination – measured as acoustic peaks in CMB fluctuations •Follow evolution of S down to lower redshift through source clustering measure angular diameter distance (‘fossilized’ acoustic oscillations vs. z) ...
... •Standard (comoving) rod, S, fixed by sound horizon (acoustic oscillations) at recombination – measured as acoustic peaks in CMB fluctuations •Follow evolution of S down to lower redshift through source clustering measure angular diameter distance (‘fossilized’ acoustic oscillations vs. z) ...
The density of very massive evolved galaxies to z≃ 1.7
... of the seven galaxies are shown. The spectra drops very rapidly at ∼0.9–1 µm concurrent with the 4000 Å break placing the galaxies at z > 1.3 and suggesting an early-type spectral nature. We searched for the best-fitting template by comparing the observed spectral energy distribution (SED) of each g ...
... of the seven galaxies are shown. The spectra drops very rapidly at ∼0.9–1 µm concurrent with the 4000 Å break placing the galaxies at z > 1.3 and suggesting an early-type spectral nature. We searched for the best-fitting template by comparing the observed spectral energy distribution (SED) of each g ...
Observing the Clustering of Matter and Galaxies
... • There is no unique way to describe clustering! – Need to describe the degree of clustering not the particular ...
... • There is no unique way to describe clustering! – Need to describe the degree of clustering not the particular ...
Big Bang and Steady State Theories
... candidates devoted a large part of their answer in doing so. Some candidates used much of the available response area by effectively writing out the question again. Some common inaccuracies were to write about planets expanding or moving away and galaxies being “red-shifted” (rather than the light f ...
... candidates devoted a large part of their answer in doing so. Some candidates used much of the available response area by effectively writing out the question again. Some common inaccuracies were to write about planets expanding or moving away and galaxies being “red-shifted” (rather than the light f ...
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).