Results 101 to 110 of about 94,086 (264)
Highly Accreting Quasars at High Redshift
Frontiers in Astronomy and Space Sciences, 2018 We present preliminary results of a spectroscopic analysis for a sample of type 1 highly accreting quasars (L/LEdd ~ 1.0) at high redshift, z ~2–3.
Mary L. Martínez-Aldama +7 more
doaj +1 more source
Quasars Probing Quasars. II. The Anisotropic Clustering of Optically Thick Absorbers around Quasars [PDF]
The 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
Journal of Applied Clinical Medical Physics, Volume 27, Issue 3, March 2026.Abstract Background Precise radiotherapy relies on accurately targeting tumours while minimising exposure to healthy tissue, yet patient and organ motion complicate treatment delivery. To address intra‐fractional motion, multi‐leaf collimator (MLC) tracking systems have recently been adopted, adapting beam shapes in real‐time.
André Haraldsson +6 more
wiley +1 more source
AllBRICQS: The Discovery of Luminous Quasars in the Northern Hemisphere
The Astrophysical Journal Supplement SeriesWe present the second catalog of bright quasars from the All-sky BRIght, Complete Quasar Survey (AllBRICQS), focusing on spectroscopically observed quasars in the Northern Hemisphere with Galactic latitude ∣ b ∣ > 10°.
Yunyi Choi +18 more
doaj +1 more source
Exploratory Chandra Observations of the Three Highest Redshift Quasars Known
, 2002 We report on exploratory Chandra observations of the three highest redshift quasars known (z = 5.82, 5.99, and 6.28), all found in the Sloan Digital Sky Survey.
Bing Chen +16 more
core +1 more source
Work in Progress: Use of Wood‐Based Inserts in Injection Molding
Engineering Reports, Volume 8, Issue 3, March 2026.The study investigates the suitability of wood‐based mold inserts for the production of small series in polymer injection molding, showing that specially modified materials like laminated beech and compressed bamboo are more promising than natural woods. The results indicate that reproducible components can be produced with these tools. ABSTRACT In the
David Grundmann +6 more
wiley +1 more source
A Deep Chandra X-Ray Survey of a Luminous Quasar Sample at z ∼ 7
The Astrophysical JournalWe present new Chandra observations of seven luminous quasars at z > 6.5. Combined with archival Chandra observations of all other known quasars, they form nearly complete X-ray observations of all currently known z ∼ 7 quasars with M _1450 < –26.5 ...
Xiangyu Jin +13 more
doaj +1 more source
New Astronomy Reviews, 2006 8 pages, 6 figures, review article with C. Impey at the conference on "QSO Host Galaxies: Evolution and Environment", Aug. 29-Sep.
Peng, Chien Y. +7 more
openaire +2 more sources
Quasar Clustering and the Lifetime of Quasars [PDF]
The Astrophysical Journal, 2001 ApJ Accepted (Feb 2001). 30 pages, 8 embedded ps figures, AASTEX5. Added discussion of quasar luminosity evolution. Also available at http://www.ociw.edu/~martini/pubs/
Martini, Paul, Weinberg, David H.
openaire +3 more sources
Anisotropy Analysis of Bamboo and Tooth Using 4‐Angle Polarization Micro‐Spectroscopy
Nano Select, Volume 7, Issue 3, March 2026.Super‐resolution via orientation: spatial distribution of specific molecular vibrations are revealed at 1/20 of the diffraction limit. ABSTRACT To investigate the anisotropic properties of biomaterials, two distinct classes are considered as follows: polymer‐based (cellulose in plants) and crystalline‐based (enamel in teeth), each demonstrating ...
Meguya Ryu +8 more
wiley +1 more source