Results 121 to 130 of about 117,210 (326)
Mathematical Methods in the Applied Sciences, EarlyView.ABSTRACT Bacteriophages, or phages (viruses of bacteria), play significant roles in shaping the diversity of bacterial communities within the human gut. A phage‐infected bacterial cell can either immediately undergo lysis (virulent/lytic infection) or enter a stable state within the host as a prophage (lysogeny) until a trigger event, called prophage ...
Hyacinthe M. Ndongmo Teytsa +3 more
wiley +1 more source
Circum-Galactic Medium in the Halo of Quasars
Frontiers in Astronomy and Space Sciences, 2017 The properties of circum-galactic gas in the halo of quasar host galaxies are investigated analyzing Mg II 2800 and C IV 1540 absorption-line systems along the line of sight close to quasars.
Riccardo Ottolina +6 more
doaj +1 more source
The Astrophysical Journal, 2023 We present bolometric luminosity ( L _bol ) and black hole (BH) mass ( M _BH ) estimators based on mid-infrared (MIR) continuum luminosity (hereafter, L _MIR ) that are measured from infrared (IR) photometric data.
Dohyeong Kim +6 more
doaj +1 more source
X-ray Observations of Gravitationally Lensed Quasars; Evidence for a Hidden Quasar Population [PDF]
, 1999 The large magnification factors of gravitationally lensed (GL) systems allow us to investigate the properties of quasars with X-ray luminosities that are substantially lower than those of unlensed ones and also provide an independent means of estimating the contribution of faint quasars to the hard X-ray component of the cosmic X-ray background.
arxiv +1 more source
A Possible Bias Model for Quasars [PDF]
Astrophys.J. 502 (1998) L95, 1998 We propose that the majority of quasars at redshift $z\sim 1 - 5$ formed in the environment of new born collapsed halos with 1-D velocity dispersion $\sigma_v^{1d} \sim 400 \kms$. The harboring coefficient $f$ of quasars per halo and the lifetime of quasars depend only on local process, not modulated by the density inhomogeneities on scales larger than
arxiv +1 more source
Medical Physics, EarlyView.Abstract Background Novel motion‐compensated treatment techniques on the MR‐linac can address adverse intra‐fraction motion effects. These techniques involve beam gating or intra‐fraction adaptations of the treatment plan based on real‐time magnetic resonance imaging (MRI) performed during treatment.
Stijn Oolbekkink +10 more
wiley +1 more source
Gravitationally lensed quasars in Gaia – II. Discovery of 24 lensed quasars [PDF]
, 2018 We report the discovery, spectroscopic confirmation and preliminary characterisation of 24 gravitationally lensed quasars identified using Gaia observations.
C. Lemon +3 more
semanticscholar +1 more source
Comprehensive Connection among the Quasars with Different Types of Outflow Absorption Lines
The Astrophysical JournalIt is commonly accepted that outflows from the central regions of quasars play a substantial role in regulating the global properties of the host galaxy. These outflows are typically detected through blueshifted absorption lines.
Xing-Long Peng +4 more
doaj +1 more source
Properties of Radio-Selected Broad Absorption-Line Quasars from the FIRST Survey [PDF]
Astrophys.J.538:72-82,2000, 2000 In a spectroscopic follow-up to the VLA FIRST survey, the FIRST Bright Quasar Survey (FBQS) has found 29 radio-selected broad absorption line (BAL) quasars. This sample provides the first opportunity to study the properties of radio-selected BAL quasars.
arxiv +1 more source
Quantifying the dosimetric accuracy of expiration‐gated stereotactic lung radiotherapy
Medical Physics, EarlyView.Abstract Background In stereotactic body radiotherapy, a form of motion management is often applied to mobile lung tumors. Gated radiotherapy is such form of motion management in which the radiation beam is switched on or off depending on the actual tumor position.
Daan Hoffmans +3 more
wiley +1 more source