Results 51 to 60 of about 52,369 (293)

Secret of Longevity: Protoplanetary Disks as a Source of Gas in Debris Disks

The Astrophysical Journal
While protoplanetary disks (PPDs) are generally thought to disperse within several million years, recent observations have revealed gas in their older counterparts, debris disks.
Wataru Ooyama, Riouhei Nakatani, Takashi Hosokawa, Hiroto Mitani, Neal J. Turner   +4 more
doaj   +1 more source

Lyα Scattering Models Trace Accretion and Outflow Kinematics in T Tauri Systems

The Astrophysical Journal, 2023
T Tauri stars produce broad Ly α emission lines that contribute ∼88% of the total UV flux incident on the inner circumstellar disks. Ly α photons are generated at the accretion shocks and in the protostellar chromospheres and must travel through ...
Nicole Arulanantham, Max Gronke, Eleonora Fiorellino, Jorge Filipe Gameiro, Antonio Frasca, Joel Green, Seok-Jun Chang, Rik A. B. Claes, Catherine C. Espaillat, Kevin France, Gregory J. Herczeg, Carlo F. Manara, Laura Venuti, Péter Ábrahám, Richard Alexander, Jerome Bouvier, Justyn Campbell-White, Jochen Eislöffel, William J. Fischer, Ágnes Kóspál, Miguel Vioque   +20 more
doaj   +1 more source

Thin accretion disk signatures of scalarized black holes in Einstein-scalar-Gauss-Bonnet gravity

Physics Letters B, 2021
Einstein-scalar-Gauss-Bonnet gravity has recently been known to exhibit spontaneous scalarization. In the presence of the Gauss-Bonnet term the no-hair theorem can be evaded and novel black hole solutions with non-trivial scalar fields have been found ...
Mohaddese Heydari-Fard, Hamid Reza Sepangi   +1 more
doaj   +1 more source

Transitional disks and their origins: an infrared spectroscopic survey of Orion A

, 2013
Transitional disks are protoplanetary disks around young stars, with inner holes or gaps which are surrounded by optically thick outer, and often inner, disks.
Arnold, Laura, Calvet, Nuria, Espaillat, Catherine, Forrest, W. J., Furlan, Elise, Green, Joel D., Kim, K. H., Manoj, P., Megeath, Tom, Muzerolle, James, Najita, Joan, Sargent, Benjamin, Watson, Dan M.   +12 more
core   +1 more source

Impact of Sustainable Binders Based on Lignin and Collagen on the Volume Stability and Mechanical Properties of MgO‐C Refractories with MgO‐C Recyclates

Advanced Engineering Materials, EarlyView.
Collagen hydrolysate is evaluated as a sustainable binder for MgO‐C refractories. Its thermally induced cross‐linking and gas release lead to expansion and cracking in large bricks, but tailored batches with lignin, recyclates, or fine graphite improve the gas release while thermal treatment and stability.
Till M. J. Stadtmüller, Florian Kerber, Kirsten Moritz, Steffen Dudczig, Konstantin Kraushaar, Thomas Schemmel, Jana Hubálková, Patrick Gehre, Christos G. Aneziris   +8 more
wiley   +1 more source

The Evolution of Accreting Binaries: From Brown Dwarfs to Supermassive Black Holes

The Astrophysical Journal
Circumbinary accretion occurs throughout the universe, from the formation of stars and planets to the aftermath of major galactic mergers. We present an extensive investigation of circumbinary accretion disks, studying circular binaries with mass ratios (
Alexander J. Dittmann, Geoffrey Ryan
doaj   +1 more source

Nucleosynthesis in Advective Accretion Disks Around Galactic and Extra-Galactic Black Holes [PDF]

, 1998
We compute the nucleosynthesis of materials inside advective disks around black holes. We show that composition of incoming matter can change significantly depending on the accretion rate and accretion disks.
B Paczyński, CJ Hogan, D Molteni, D Molteni, I Yi, JF Hawley, JW Hawley, L Jin, L Jin, MJ Rees, S Chakrabarti, S Ramadurai, SK Chakrabarti, SK Chakrabarti, SK Chakrabarti, SK Chakrabarti, SK Chakrabarti, SL Shapiro, TK Das   +18 more
core   +3 more sources

Impact of Pre‐Oxidation Treatments on a Recycled MgO/Steel‐Composite as Carbon Free Anode in Aluminum‐Electrolysis Environments

Advanced Engineering Materials, EarlyView.
Cermets (60 vol.% AISI 316L stainless steel, 40 vol.% recycled MgO), intended for use in aluminum electrolysis, were pre‐oxidized in three furnaces with different heating technologies and subjected to a cryolite corrosion test. The different atmospheres influenced the formation of oxide layers, which in turn affected corrosion resistance and ...
Patricia Kaiser, Felix Drechsler, Nora Brachhold, Florian Kerber, Christos G. Aneziris   +4 more
wiley   +1 more source

Using the Ca ii Lines in T Tauri Stars to Infer the Abundance of Refractory Elements in the Innermost Disk Region

The Astrophysical Journal
We present a study of the abundance of calcium in the innermost disk of 70 T Tauri stars in the star-forming regions of Chamaeleon I, Lupus, and Orion OB1b. We use calcium as a proxy for the refractory material that reaches the inner disk.
Marbely Micolta, Nuria Calvet, Thanawuth Thanathibodee, Gladis Magris C., Carlo F. Manara, Laura Venuti, Juan Manuel Alcalá, Gregory J. Herczeg   +7 more
doaj   +1 more source

Direct URCA Processes in Supernovae and Accretion Disks with Arbitrary Magnetic Field

EPJ Web of Conferences, 2017
An effect of a magnetic field of an arbitrary strength on the beta-decay and reactions related with it by the crossing symmetry (the beta-processes) in supernovae and accretion disks around black holes is analyzed.
Ognev Igor
doaj   +1 more source