搜索结果: 1-15 共查到“理学 Quasar”相关记录41条 . 查询时间(0.109 秒)
A distant quasar may have its light split into multiple images by a foreground galaxy cluster that acts as a gravitational lens. The light travels along different paths of differing lengths to form ea...
CO(1-0) in z gtrsim 4 Quasar Host Galaxies: No Evidence for Extended Molecular Gas Reservoirs
formation high-redshift
2014/12/24
We present 12CO(J = 1 → 0) observations of the high-redshift quasi-stellar objects (QSOs) BR 1202-0725 (z = 4.69), PSS J2322+1944 (z = 4.12), and APM 08279+5255 (z = 3.91) using the NRAO Green Bank Te...
USING 21 cm ABSORPTION IN SMALL IMPACT PARAMETER GALAXY-QUASAR PAIRS TO PROBE LOW-REDSHIFT DAMPED AND SUB-DAMPED Ly alpha SYSTEMS
low-redshift damped Lyα (DLA) sub-DLA quasar absorbers
2014/12/20
To search for low-redshift damped Lyα (DLA) and sub-DLA quasar absorbers, we have conducted a 21 cm absorption survey of radio-loud quasars at small impact parameters to foreground galaxies selected f...
Astronomers have discovered a distant quasar illuminating a vast nebula of diffuse gas, revealing for the first time part of the network of filaments thought to connect galaxies in a cosmic web. Resea...
An Anomaly in the Angular Distribution of Quasar Magnitudes: Evidence for a Bubble Universe with a Mass ~10^21 M\odot
Anomaly Angular Distribution Quasar Magnitudes Bubble Universe Mass
2012/2/21
Quasars provide our farthest-reaching view of the Universe. The Sloan Survey now contains over 100,000 quasar candidates. A careful look at the angular distribution of quasar magnitudes shows a surpri...
Simulations of BAO reconstruction with a quasar Lyman-alpha survey
cosmology dark energy - cosmology: LSS - Galaxies: IGM - Galaxies: quasars- Method: numerical
2011/10/12
The imprint of Baryonic Acoustic Oscillations (BAO) on the matter power spectrum can be constrained using the neutral hydrogen density in the intergalactic medium as a tracer of the matter density. On...
The radio core of the Ultraluminous Infrared Galaxy F00183-7111: watching the birth of a quasar
radio continuum: galaxies-galaxies: evolution-galaxies: ULIRG-galaxies: active-VLBI
2011/10/12
F00183-7111 is one of the most extreme Ultra-Luminous Infrared Galaxies known. Here we present a VLBI image which shows that F00183-7111 is powered by a combination of a radio-loud Active Galactic Nuc...
The New Generation Atlas of Quasar Spectral Energy Distributions from Radio to X-rays
Generation Atlas Spectral Energy Distributions Radio
2011/9/30
We have produced the next generation of quasar spectral energy distributions (SEDs), essentially updating the work of Elvis et al. (1994) by using high-quality data obtained with several space and gro...
SDSS J133401.39+331534.3: A New Subarcsecond Gravitationally Lensed Quasar
Subarcsecond Gravitationally Lensed Quasar
2011/9/29
The quasar SDSS J133401.39+331534.3 at z = 2.426 is found to be a two-image gravitationally lensed quasar with the image separation of 0.833. The object is first identified as a lensed quasar candidat...
A New Microlensing Event in the Doubly-Imaged Quasar Q0957+561
Microlensing Event Doubly-Imaged Quasar
2011/9/28
We present evidence for ultraviolet/optical microlensing in the gravitationally lensed quasar Q0957+561. We combine new measurements from our optical monitoring campaign at the United States Naval Obs...
The Transition from "Normal" to "Broad Absorption Line Quasar" of Ton 34
Normal Broad Absorption Line Quasar
2011/1/10
We report the emergence of a high velocity, broad absorption line outflow in the luminous quasar Ton 34, at z=1.928. The outflow is detected through an ultraviolet CIV broad absorption line, in a spec...
Orientation effects in quasar spectra: The broad- and narrow-line regions
Orientation effects quasar spectra
2011/1/11
We use the SDSS, along with the NVSS and the WENSS to define a sample of 746 radio-loud quasars and measure their 330MHz to 1.4GHz spectral indexes. Following previous authors we take the spectral ind...
Dense Molecular Gas Excitation at High Redshift: Detection of HCO+(J=4-3) Emission in the Cloverleaf Quasar
galaxies active — galaxies starburst — galaxies formation — galaxies
2010/11/10
We report the detection of HCO+(J=4→3) emission in the Cloverleaf Quasar at z=2.56, using
the IRAM Plateau de Bure Interferometer. HCO+ emission is a star formation indicator similar
to HCN, tracing...
Absence of a Periodic Component in Quasar z-Distribution
arge-scale structure of Universe quasars general catalogues,methods data analysis
2010/11/10
Since the discovery of quasars in papers often appeared and appear the assertions that the redshift quasar distribution includes a periodic component with the period z = 0.063 or 0.11. A statement of...
Probing the faint end of the quasar luminosity function at z ~ 4 in the COSMOS field
cosmology observations — quasars general — surveys
2010/11/12
We searched for quasars that are 3 mag fainter than the SDSS quasars in the redshift range 3.7 . z . 4.7 in the COSMOS field to constrain the faint end of the quasar luminosity function.