Results 71 to 80 of about 69,486 (315)

An irradiated brown-dwarf companion to an accreting white dwarf [PDF]

Nature, 2016
Brown dwarfs and giant planets orbiting close to a host star are subjected to significant irradiation that can modify the properties of their atmospheres. In order to test the atmospheric models that are used to describe these systems, it is necessary to obtain accurate observational estimates of their physical properties (masses, radii, temperatures ...
S. P. Littlefair, M. L. Pretorius, Juan V. Hernández Santisteban, V. S. Dhillon, Rene P. Breton, Rene P. Breton, Boris T. Gänsicke, John Southworth, Christian Knigge, Tom Marsh, Peter H. Hauschildt   +10 more
openaire   +9 more sources

The Insistence of Blackness and the Persistence of Antiblackness in Ireland

Australian Journal of Social Issues, EarlyView.
ABSTRACT This paper positions Ireland as a critical site for examining the insistence of blackness and an antiblackness created and sustained through Irish ethnonationalist imaginaries and exclusionary processes. Drawing on connected sociologies and Irish Black Studies, this enquiry argues that antiblackness in Ireland operates as a generational force,
Philomena Mullen
wiley   +1 more source

A Test of Spectroscopic Age Estimates of White Dwarfs Using Wide WD+WD Binaries

The Astrophysical Journal
White dwarf stars have been used for decades as precise and accurate age indicators. This work presents a test of the reliability of white dwarf total ages when spectroscopic observations are available. We conduct follow-up spectroscopy of 148 individual
Tyler M. Heintz, J. J. Hermes, P.-E. Tremblay, Lou Baya Ould Rouis, Joshua S. Reding, B. C. Kaiser, Jennifer L. van Saders   +6 more
doaj   +1 more source

Orbital Decay in an Accreting and Eclipsing 13.7 Minute Orbital Period Binary with a Luminous Donor

The Astrophysical Journal Letters, 2023
We report the discovery of ZTF J0127+5258, a compact mass-transferring binary with an orbital period of 13.7 minutes. The system contains a white dwarf accretor, which likely originated as a post–common envelope carbon–oxygen (CO) white dwarf, and a warm
Kevin B. Burdge, Kareem El-Badry, Saul Rappaport, Tin Long Sunny Wong, Evan B. Bauer, Lars Bildsten, Ilaria Caiazzo, Deepto Chakrabarty, Emma Chickles, Matthew J. Graham, Erin Kara, S. R. Kulkarni, Thomas R. Marsh, Melania Nynka, Thomas A. Prince, Robert A. Simcoe, Jan van Roestel, Zach Vanderbosch, Eric C. Bellm, Richard G. Dekany, Andrew J. Drake, George Helou, Frank J. Masci, Jennifer Milburn, Reed Riddle, Ben Rusholme, Roger Smith   +26 more
doaj   +1 more source

Absolute Proper Motions to B~22.5: IV. Faint, Low Velocity White Dwarfs and the White Dwarf Population Density Law [PDF]

, 2001
The reduced proper motion diagram (RPMD) for a complete sample of faint stars with high accuracy proper motions in the North Galactic Pole field SA57 is investigated. Eight stars with very large reduced proper motions are identified as faint white dwarf candidates.
arxiv   +1 more source

The Halo White Dwarf Population [PDF]

The Astrophysical Journal, 1998
29 pages (AASTeX), 7 eps figures included, accepted for publication in ...
Enrique García-Berro, Jordi Isern, Margarita Hernanz, Santiago Torres, R. Mochkovitch   +4 more
openaire   +3 more sources

Histochemical indications for a chemically complex signal produced by the cervical gill slit gland of the pygmy sperm whale (Kogia breviceps)

The Anatomical Record, EarlyView.
Abstract The pygmy sperm whale (Kogia breviceps) possesses an exocrine gland associated with its false gill slit pigmentation pattern. The cervical gill slit gland is a compound tubuloalveolar gland that produces a holocrine secretion and displays maturational changes in size and secretory histology. While the morphology of the cervical gill slit gland
Tiffany F. Keenan, William A. McLellan, Sentiel A. Rommel, Alexander M. Costidis, Craig A. Harms, J. G. M. Thewissen, Susan J. Rehorek, David S. Rotstein, Mark D. Gay, Alison R. Taylor, Heather N. Koopman, Ying Wang, Stephanie Kamel, D. Ann Pabst   +13 more
wiley   +1 more source

Presupernova evolution of accreting white dwarfs with rotation [PDF]

Astron.Astrophys. 419 (2004) 623, 2004
We discuss the effects of rotation on the evolution of accreting carbon-oxygen white dwarfs, with the emphasis on possible consequences in Type Ia supernova (SN Ia) progenitors. Starting with a slowly rotating white dwarf, we simulate the accretion of matter and angular momentum from a quasi-Keplerian accretion disk.
arxiv   +1 more source

RNA‐Based Biopesticides: Pioneering Precision Solutions for Sustainable Aquaculture in China

Animal Research and One Health, EarlyView.
The Chinese dragon represents RNA biopesticides, which effectively counteract bacterial, viral, and parasitic threats, safeguarding aquatic life. This method is precise, focusing solely on harmful agents and sparing beneficial aquaculture species. Its innovative nature protects aquatic environments while reducing ecological footprint.
Yiran Huang, Yingmin Dai, Zhuotong Huang, Mengqi Zhang, Lijun Xiu, Xianhui Zhang, Youyu Zhang, Lixing Huang   +7 more
wiley   +1 more source

New white dwarf stars in the Sloan Digital Sky Survey Data Release 10 [PDF]

, 2014
We report the discovery of 9 089 new spectroscopically confirmed white dwarfs and subdwarfs in the Sloan Digital Sky Survey Data Release 10. We obtain Teff, log g and mass for hydrogen atmosphere white dwarf stars (DAs) and helium atmosphere white dwarf stars (DBs), and estimate the calcium/helium abundances for the white dwarf stars with metallic ...
arxiv   +1 more source