Results 131 to 140 of about 110,927 (295)

Quasars Probing Quasars. II. The Anisotropic Clustering of Optically Thick Absorbers around Quasars [PDF]

open access: yesThe Astrophysical Journal, 2007
With close pairs of quasars at different redshifts, a background quasar sightline can be used to study a foreground quasar's environment in absorption. We used a sample of 17 Lyman limit systems with column density N_HI > 10^19 cm^-2 selected from 149 projected quasar pair sightlines, to investigate the clustering pattern of optically thick ...
Hennawi, Joseph F., Prochaska, Jason X.
openaire   +2 more sources

Simultaneous liver T1, T2, and ADC MR fingerprinting using optimized motion‐compensated diffusion preparations: An initial validation on volunteers

open access: yesMagnetic Resonance in Medicine, Volume 94, Issue 5, Page 2173-2189, November 2025.
Abstract Purpose To develop a novel MR fingerprinting sequence using optimized motion‐compensated diffusion preparations for simultaneous T1, T2, and ADC quantification of liver tissue in a single breath‐held scan. Methods A radial spoiled gradient echo acquisition with magnetization preparation modules for T1, T2, and ADC encoding is proposed.
C. Velasco   +7 more
wiley   +1 more source

The Physical Properties of Low-redshift FeLoBAL Quasars. IV. Optical–Near-IR Spectral Energy Distributions and Near-IR Variability Properties

open access: yesThe Astrophysical Journal
We present the optical–near-infrared spectral energy distributions (SED) and near-infrared variability properties of 30 low-redshift iron low-ionization Broad Absorption Line quasars (FeLoBALQs) and matched samples of LoBALQs and unabsorbed quasars ...
Karen M. Leighly   +5 more
doaj   +1 more source

Perfusion Territory Shifts in Cerebrovascular Diseases Measured by Super‐Selective Arterial Spin Labeling

open access: yesJournal of Neuroimaging, Volume 35, Issue 6, November/December 2025.
ABSTRACT Background and Purpose Individualized diagnostic approaches are crucial in cerebrovascular diseases, such as internal carotid artery stenosis (ICAS). To evaluate individual collateral blood supply, vessel‐selective imaging has gained high relevance.
Gabriel Hoffmann   +12 more
wiley   +1 more source

VODKA-JWST: Synchronized Growth of Two Supermassive Black Holes in a Massive Gas Disk? A 3.8 kpc Separation Dual Quasar at Cosmic Noon with the NIRSpec Integral Field Unit

open access: yesThe Astrophysical Journal
The search for dual supermassive black holes (SMBHs) is of immense interest in modern astrophysics. Galaxy mergers may fuel and produce SMBH pairs. Actively accreting SMBH pairs are observed as dual quasars, which are vital probes of SMBH growth.
Yuzo Ishikawa   +12 more
doaj   +1 more source

3D SR‐μXCT analysis for lithology detection: Application to Ryugu sample A0159

open access: yesMeteoritics &Planetary Science, Volume 60, Issue 11, Page 2623-2654, November 2025.
Abstract Extraterrestrial breccia samples are formed through impact‐related processes that combine the fragments of distinct lithologies. As such, they are valuable indicators of the complex formation and evolution history of planetesimals in our solar system.
Léna Jossé   +9 more
wiley   +1 more source

Gravitationally lensed quasars in Gaia – II. Discovery of 24 lensed quasars [PDF]

open access: yes, 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

ISO Observations of Quasars and Quasar Hosts [PDF]

open access: yes, 1997
The Infrared Space Observatory (ISO), launched in November 1995, allows us to measure the far-infrared (far-IR) emission of quasars in greater detail and over a wider energy range than previously possible. In this paper, preliminary results in a study of the 5--200 $ m$ continuum of quasars and active galaxies are presented. Comparison of the spectral
openaire   +2 more sources

Highly multiplexed digital PCR assay for simultaneous quantification of variant allele frequencies and copy number alterations of KRAS and GNAS in pancreatic cancer precursors

open access: yesMolecular Oncology, Volume 19, Issue 10, Page 2921-2935, October 2025.
Combining melting curve analysis enhances the multiplexing capability of digital PCR. Here, we developed a 14‐plex assay to simultaneously measure single nucleotide mutations and amplifications of KRAS and GNAS, which are common driver genes in pancreatic cancer precursors. This assay accurately quantified variant allele frequencies in clinical samples
Junko Tanaka   +10 more
wiley   +1 more source

Machine Learning–based Search of High-redshift Quasars

open access: yesThe Astrophysical Journal Supplement Series
We present a machine learning search for high-redshift (5.0 < z < 6.5) quasars using the combined photometric data from the Dark Energy Spectroscopic Instrument (DESI) Imaging Legacy Surveys and the Wide-field Infrared Survey Explorer survey.
Guangping Ye, Huanian Zhang, Qingwen Wu
doaj   +1 more source

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