搜索结果: 1-14 共查到“天文学 redshifts”相关记录14条 . 查询时间(0.156 秒)
Radio-to-Far-Infrared Spectral Energy Distribution and Photometric Redshifts for Dusty Starburst Galaxies
galaxies photometric
2014/12/26
As a logical next step in improving the radio-to-submillimeter spectral index as a redshift indicator, we have investigated a technique of using the entire radio-to-far-infrared spectral energy distri...
Toward a precise measurement of matter clustering: Ly alpha forest data at redshifts 2-4
absorption lines large scale structure of universe
2014/12/26
We measure the filling factor, correlation function, and power spectrum of transmitted flux in a large sample of Lyα forest spectra, comprised of 30 Keck HIRES spectra and 23 Keck LRIS spectra. We inf...
The morphological diversities among star-forming galaxies at high redshifts in the great observatories origins deep survey
high-redshift fundamental parameters
2014/12/24
We used the deep, multiwavelength images obtained by the Great Observatories Origins Deep Survey (GOODS) to identify ~4700 Lyman break galaxies (LBGs) at z > 2.5, and 292 starburst galaxies at z ~ 1.2...
Dust grain growth in the interstellar medium of galaxies at redshifts 4
Dust grain growth interstellar medium galaxies redshifts
2011/10/21
To discriminate between different dust formation processes is a key issue in order to understand its properties. We analysed six submillimeter galaxies at redshifts 4rs at 5
Astroinformatics of galaxies and quasars: a new general method for photometric redshifts estimation
cosmology: observations galaxies: redshifts methods: data mining surveys
2011/10/10
With the availability of the huge amounts of data produced by current and future large multi-band photometric surveys, photometric redshifts have become a crucial tool for extragalactic astronomy and ...
Formation of galactic nuclei with multiple supermassive black holes at high redshifts
black hole physics – galaxies:nuclei – galaxies:evolution – galaxies:high redshift – galaxies:kinematics dynamics
2011/9/27
We examine the formation of groups of multiple supermassive black holes (SMBHs) in gas-poor galactic nuclei due to the high merger rate of galaxies at high redshifts. We calculate the relative likelih...
Calibrating Galaxy Redshifts Using Absorption by the Surrounding Intergalactic Medium
galaxies high-redshift intergalactic medium quasars absorption lines
2010/11/11
Rest-frame UV spectral lines of star-forming galaxies are systematically offset fromthe galaxies’systemic redshifts, probably because of large-scale outflows.We calibrate galaxy redshifts measured fro...
Photometric redshifts for GRB afterglows from GROND and Swift/UVOT
gamma rays bursts Techniques photometric
2010/11/11
Aims. We present a framework to obtain photometric redshifts (photo-zs) for gamma-ray burst afterglows. Using multi-band photometry from GROND and Swift/UVOT, photo-zs are derived for five GRBs for wh...
The Dark Side of QSO Formation at High Redshifts
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2011/1/7
Observed high-redshift QSOs, at z~6, may reside in massive dark matter (DM) halos of more than 10^{12} Msun and are thus expected to be surrounded by overdense regions. In a series of 10 constrained s...
Spectrophotometric Redshifts. A New Approach to the Reduction of Noisy Spectra and its Application to GRB090423
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2010/12/27
We have developed a new method, close in philosophy to the photometric redshift technique, which can be applied to spectral data of very low signal-to-noise ratio. Using it we intend to measure redshi...
Close Separation Triple System QSO 1009–0252 with Discordant Redshifts:
Quasars emission lines absorption lines—individual
2010/9/15
1009-0252 is a Quasi Stellar Object (QSO) with three components A, B, C. A, B are thought to be the result of gravitational lensing of one object, and A, C constitute a close pair with redshifts 2.74 ...
HI Fluctuations at Large Redshifts：I -Visibility correlation
large scale structures diffuse radiation
2009/5/20
We investigate the possibility of probing the large scale
structure in the universe at large redshifts by studying fluctuations in the
redshifted 1420 MHz emission from the neutral hydrogen (HI) at ...
HI Fluctuations at Large Redshifts: III – Simulating the Signal Expected at GMRT
Cosmology large scale structures radiation
2009/5/19
We simulate the distribution of neutral hydrogen (HI) at
the redshifts z D 1:3 and 3:4 using a cosmological N-body simulation
along with a prescription for assigning HI masses to the particles. The...
HI Fluctuations at Large Redshifts：II – the Signal Expected for theGMRT
Cosmology large scale structures
2009/5/18
For the GMRT, we calculate the expected signal from redshifted
HI emission at two frequency bands centered at 610 and 325MHz.
The study focuses on the visibility-visibility cross-correlations, propo...