Results 91 to 100 of about 20,094 (246)

Stability of the protogalactic clouds - I: Field length in the adiabatic models [PDF]

Serbian Astronomical Journal, 1999
All gasdynamical models for the evolution of gaseous content of galaxies assume that cooling from the hot, virialized phase to the cold phase occurred through some sort of thermal instability.
Ćirković M.M.
doaj   +1 more source

Quasar Radio-Loudness and the Elliptical Core Problem

, 2010
The dichotomy between radio-loud and radio-quiet QSOs is not simply one of host morphology. While spiral galaxies almost exclusively host radio-quiet QSOs, ellipticals can host either radio-louds or radio-quiets.
Bahcall, Boroson, Brinkmann, Crane, Diehl, Djorgovski, Dressler, Faber, Falcke, Fasano, Ferrarese, Gebhardt, Guyon, Hamabe, Hamilton, Hamilton, Kormendy, Kormendy, Laor, Liu, Magorrian, McLure, Merloni, Peacock, Timothy S. Hamilton, Trager, Trujillo, Tsutsui, Wang, Whitmore, Yip, Yuan, Zamfir   +32 more
core   +1 more source

On the Periodic Redshifts of Galaxies and Associated QSOs [PDF]

, 2017
: The observed periodicity of intrinsic-redshift in galaxies and associated QSOs has been explained by using the previous theory of a gravito-cordic field for galaxies. The quantisation period is a function of the atomic fine structure constant and it
WAYTE, RICHARD
core   +1 more source

Canopy temperatures strongly overestimate leaf thermal safety margins of tropical trees

New Phytologist, Volume 243, Issue 6, Page 2115-2129, September 2024.
Summary Current estimates of temperature effects on plants mostly rely on air temperature, although it can significantly deviate from leaf temperature (Tleaf). To address this, some studies have used canopy temperature (Tcan). However, Tcan fails to capture the fine‐scale variation in Tleaf among leaves and species in diverse canopies. We used infrared
Olivier Jean Leonce Manzi, Maria Wittemann, Mirindi Eric Dusenge, Jacques Habimana, Aloysie Manishimwe, Myriam Mujawamariya, Bonaventure Ntirugulirwa, Etienne Zibera, Lasse Tarvainen, Donat Nsabimana, Göran Wallin, Johan Uddling   +11 more
wiley   +1 more source

Mid-Infrared Spectroscopic Properties of Ultra-Luminous Infrared Quasars

, 2008
We analyse mid-infrared (MIR) spectroscopic properties for 19 ultra-luminous infrared quasars (IR QSOs) in the local universe based on the spectra from the Infrared Spectrograph on board the Spitzer Space Telescope.
Armus, Armus, Batcheldor, Boroson, Brandl, C. N. Hao, Calzetti, Canalizo, Canalizo, Carilli, Chen Cao, Cui, de Kool, Desai, Downes, Evans, Farrah, Farrah, Ferrarese, Gallagher, Ganguly, Haas, Hamann, Hao, Hao, Hao, Hao, Heckman, Higdon, Ho, Ho, Hong Wu, Houck, Houck, Imanishi, Kim, Lawrence, Leighly, Lonsdale, Low, Lípari, Magorrian, Netzer, Neugebauer, Neugebauer, Rieke, Rowan-Robinson, S. Mao, Sanders, Sanders, Saunders, Schmidt, Schweitzer, Shi, Silk, Smith, Spoon, Spoon, Veilleux, Veilleux, Voit, Wang, Wang, Werner, Weymann, Weymann, Wu, Wu, Wu, X. Y. Xia, Z. G. Deng, Zheng, Zheng   +72 more
core   +2 more sources

Properties of low-redshift QSO absorption systems - QSO-galaxy pairs [PDF]

Publications of the Astronomical Society of the Pacific, 1993
The chance proximity of QSOs and galaxies provides unique opportunities to probe the extent and content of gas in the foreground galaxies through evaluation of the incidence and strength of absorption lines in the spectra of the background QSOs. Recent results on the observed properties of these low-redshift, heavy-element absorption systems are ...
openaire   +1 more source

Radio-quiet QSO environments — I. The correlation of QSOs and bJ < 23 galaxies [PDF]

Monthly Notices of the Royal Astronomical Society, 1999
14 pages, 13 figures, submitted to ...
Croom, S. M., Shanks, T.
openaire   +2 more sources

The large, bright QSO survey. V - QSOs in three southern fields [PDF]

The Astronomical Journal, 1991
This is the fifth and final paper in a series reporting the results of a program aimed at selecting ∼1000 QSOs brighter than B J ⇒ 18.75 using machine-scanned direct and objective-prism plates from the UK Schmidt Telescope. The plate material is scanned at the Automated Plate Measuring facility.
Morris, Simon L., Weymann, Ray J., Anderson, Scott F., Hewett, Paul C., Francis, Paul, Foltz, Craig B., Chaffee, Frederic H., MacAlpine, Gordon M.   +7 more
openaire   +2 more sources

A halo model approach for mock catalogs of time-variable strong gravitational lenses

The Open Journal of Astrophysics
Time delays in both galaxy- and cluster-scale strong gravitational lenses have recently attracted a lot of attention in the context of the Hubble tension.
Katsuya T. Abe, Masamune Oguri, Simon Birrer, Narayan Khadka, Philip J. Marshall, Cameron Lemon, Anupreeta More, the LSST Dark Energy Science Collaboration   +7 more
doaj   +1 more source

Probing Ultralate Reionization: Direct Measurements of the Mean Free Path over 5 < z < 6

The Astrophysical Journal, 2023
The mean free path of ionizing photons, λ _mfp , is a critical parameter for modeling the intergalactic medium (IGM) both during and after reionization.
Yongda Zhu, George D. Becker, Holly M. Christenson, Anson D’Aloisio, Sarah E. I. Bosman, Tom Bakx, Valentina D’Odorico, Manuela Bischetti, Christopher Cain, Frederick B. Davies, Rebecca L. Davies, Anna-Christina Eilers, Xiaohui Fan, Prakash Gaikwad, Martin G. Haehnelt, Laura C. Keating, Girish Kulkarni, Samuel Lai, Hai-Xia Ma, Andrei Mesinger, Yuxiang Qin, Sindhu Satyavolu, Tsutomu T. Takeuchi, Hideki Umehata, Jinyi Yang   +24 more
doaj   +1 more source