搜索结果: 16-30 共查到“天文学 nuclei”相关记录52条 . 查询时间(0.093 秒)
Search for Nuclei Sources in the Ultra-High Energy Cosmic Ray Data
Ultra-High Energy Cosmic Rays Galactic Magnetic Field
2011/10/8
We present a new method to search for heavy nuclei sources, on top of background, in the Ultra-High Energy Cosmic Ray data. We apply it to the 69 events with energies E>55 EeV published by the Pierre ...
Dual-Frequency Observations of 140 Compact, Flat-Spectrum Active Galactic Nuclei for Scintillation-Induced Variability
Flat-Spectrum Active Galactic Nuclei Variability
2011/10/8
The 4.9 GHz Micro-Arcsecond Scintillation-Induced Variability (MASIV) Survey detected a drop in Interstellar Scintillation (ISS) for sources at redshifts z > 2, indicating an apparent increase in angu...
Recent results of the Pierre Auger (Auger) fluorescence detectors indicate an increasingly heavy composition of ultra-high energy (UHE) cosmic rays (CRs). Assuming that this trend continues up to the ...
Mass Loss, Destruction and Detection of Sun-grazing and -impacting Cometary Nuclei
comet sun impact sun-grazing radiation collisions
2011/9/30
Incoming sun-grazing comets almost never re-emerge, but no final destruction event has ever been observed, nor sun-impactor destruction theory developed. We seek analytic models of comet nucleus destr...
Near-Infrared Reverberation by Dusty Clumpy Tori in Active Galactic Nuclei
Near-Infrared Reverberation Dusty Clumpy Active Galactic Nuclei
2011/9/27
According to recent models, the accretion disk and black hole in active galactic nuclei are surrounded by a clumpy torus. We investigate the NIR flux variation of the torus in response to a UV flash f...
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...
Chandra High Energy Grating Observations of the Fe Ka Line Core in Type 2 Seyfert Galaxies: A Comparison with Type 1 Nuclei
galaxies active – line:profile – X-rays:galaxies
2011/8/24
We present a study of the core of the Fe Ka emission line at ~6.4 keV in a sample of type II Seyfert galaxies observed by the Chandra High Energy Grating (HEG). The sample consists of 29 observations ...
Chandra High Energy Grating Observations of the Fe Ka Line Core in Type 2 Seyfert Galaxies: A Comparison with Type 1 Nuclei
Grating Observations Seyfert Galaxies Comparison
2011/9/26
We present a study of the core of the Fe Ka emission line at ~6.4 keV in a sample of type II Seyfert galaxies observed by the Chandra High Energy Grating (HEG). The sample consists of 29 observations ...
The Mid-Infrared High-Ionization Lines from Active Galactic Nuclei and Star-Forming Galaxies
The Mid-Infrared High-Ionization Lines Active Galactic Nuclei Star-Forming Galaxies
2011/1/10
We used Spitzer/IRS spectroscopic data on 426 galaxies including quasars, Seyferts, LINER and HII galaxies to investigate the relationship among the mid-IR emission lines. There is a tight linear corr...
This work represents the final year project for BSc Physics with Astrophysics degree and it mainly focuses on empirical investigation of the photometry of quasars in the Sloan Digital Sky Survey (SDSS...
Ultrahigh-energy nuclei, photons, and magnetic fields
Ultrahigh-energy nuclei photons magnetic fields
2011/1/10
Combined recent data from cosmic-ray detectors and gamma-ray detectors have produced some surprising insights regarding the sources of ultrahigh-energy cosmic rays (UHECRs), magnetic fields inside and...
The origin of the Broad Line Region in Active Galactic Nuclei
the Broad Line Active Galactic Nuclei
2011/1/13
Although broad emission lines are the most reliable signature of the nuclear activity of a galaxy and the location of the emitting material is well measured by the reverberation method, the physical ...
The 1.6 micron near infrared nuclei of 3C radio galaxies: Jets, thermal emission or scattered light?
infrared nuclei 3C radio galaxies
2011/1/11
Using HST NICMOS 2 observations we have measured 1.6-micron near infrared nuclear luminosities of 100 3CR radio galaxies with z<0.3, by modeling and subtracting the extended emission from the host gal...
The Compton shoulder of the Fe Kalpha fluorescent emission line in active galactic nuclei
The Compton shoulder the Fe Kalpha fluorescent emission line
2011/1/11
We present new, high signal-to-noise ratio results from a Monte Carlo study of the properties of the Compton shoulder of the Fe Kalpha emission line in the toroidal X-ray reprocessor model of Murphy &...
Revisiting with Chandra the Scaling Relations of the X-ray Emission Components (Binaries, Nuclei and Hot Gas) of Early Type Galaxies
galaxies elliptical and lenticular – X-rays galaxies
2010/11/15
We have selected a sample of 30 normal (non-cD) early type galaxies, for all of which optical spectroscopy is available, and which have been observed with Chandra to a depth such to insure the detecti...