Results 81 to 90 of about 726,750 (238)

NLTE Analysis of High-Resolution H-Band Spectra, V: Neutral Sodium

Universe, 2023
In order to derive sodium abundances and investigate the effects of non-local thermodynamic equilibrium (NLTE) on the formation of H-band Na I lines, we update the sodium atomic model by incorporating collision rates with hydrogen from new quantum ...
Zeming Zhou, Jianrong Shi, Shaolan Bi, Hongliang Yan, Junbo Zhang, Kaike Pan, Xiaodong Xu   +6 more
doaj   +1 more source

Atomic data from the IRON project - LI. Electron impact excitation of FeIX [PDF]

, 2002
We calculate collision strengths and thermally averaged collision strengths for electron excitation between the one hundred and forty energetically lowest levels of Fe8+.
Le Dourneuf, M, Storey, PJ, Zeippen, CJ
core  

Shock-powered light curves of luminous red novae as signatures of pre-dynamical mass loss in stellar mergers [PDF]

, 2017
Luminous red novae (LRN) are a class of optical transients believed to originate from the mergers of binary stars, or "common envelope" events. Their light curves often show secondary maxima, which cannot be explained in the previous models of thermal ...
B. Metzger, O. Pejcha
semanticscholar   +1 more source

Binary Stars Approaching Supermassive Black Holes: Tidal Breakup, Double Stellar Disruptions, and Stellar Collision

The Astrophysical Journal
In galactic centers, stars and binaries can be injected into low-angular-momentum orbits, resulting in close encounters with the central supermassive black hole (SMBH).
Fangyuan Yu, Dong Lai
doaj   +1 more source

Collisional Cascades in Planetesimal Disks I. Stellar Flybys [PDF]

, 2001
We use a new multiannulus planetesimal accretion code to investigate the evolution of a planetesimal disk following a moderately close encounter with a passing star.
Augereau J.-C., Augereau J.-C., Barge P., Benjamin C. Bromley, Davis D. R., Dent W. R. F., Dohnanyi J. W., Kalas P., Krivov A. V., Larwood J. D., Lecavelier des Etangs A., Mouillet D., Ohtsuki K., Scott J. Kenyon, Weidenschilling S. J.   +14 more
core   +3 more sources

Nonthermal Emission from Stellar Bow Shocks [PDF]

Astrophysical Journal, 2018
Since the detection of nonthermal radio emission from the bow shock of the massive runaway star BD +43°3654, simple models have predicted high-energy emission, at X-rays and gamma-rays, from these Galactic sources.
M. V. D. Valle, M. Pohl
semanticscholar   +1 more source

Non-thermal emission processes in massive binaries [PDF]

, 2007
In this paper, I present a general discussion of several astrophysical processes likely to play a role in the production of non-thermal emission in massive stars, with emphasis on massive binaries.
A Decourchelle, A Feldmeier, A Feldmeier, A Konopelko, A Maeder, A Maeder, A Pauldrach, A Reimer, AE Wright, AFJ Moffat, AMT Pollock, AR Bell, AR Bell, AR Bell, AWA Pauldrach, B García, C Cappa, C Leitherer, C Leitherer, C Neiner, CA Tout, CG Campbell, D Eichler, D Moss, DB Melrose, DC Abbott, DC Abbott, DC Abbott, DF Torres, DR Florkowski, DR Gies, DR Gies, DYA Setia Gunawan, E Fermi, E Quataert, EN Parker, EP Nelan, F Aharonian, F Aharonian, G Michaud, G Rauw, G Rauw, GB Rybicki, GD Schmidt, GR Blumenthal, H Sana, HC Spruit, HC Spruit, IR Stevens, J MacDonald, JA Harvin, JC Brown, JF Donati, JF Donati, JH Bieging, JI Castor, JL Tassoul, JM Chapman, JM Pittard, JM Pittard, JM Pittard, JS Vink, KB MacGregor, KS Cheng, L Ferrario, LB Lucy, LB Lucy, LL Kitchatinov, M De Becker, M De Becker, M De Becker, M De Becker, M De Becker, M De Becker, M De Becker, ME Contreras, MG Baring, Michaël De Becker, MS Longair, N Panagia, NS Schulz, P Benaglia, P Benaglia, P Benaglia, P Benaglia, P Benaglia, P Charbonneau, PM Williams, PM Williams, R Aznar Cuadrado, R Blomme, R Blomme, RD Blandford, RK Manchanda, RL White, RL White, RL White, S Hubrig, S Van Loo, SA Drake, SL Skinner, SM Dougherty, SM Dougherty, SM Dougherty, SM Kahn, SP Owocki, SP Owocki, T Eversberg, T Paumard, TG Cowling, TW Berghoefer, VV Usov, W Chen, YM Butt   +113 more
core   +1 more source

Frequency of Stellar Collisions in Three-Body Heating [PDF]

Symposium - International Astronomical Union, 1996
The probability for collisional interaction of three body binaries is calculated as a function of the physical radius and mass of the stellar objects and the depth of the cluster potential well. For typical cluster parameters, there is a significant chance of physical collision for objects as small as white dwarfs.
Xiaolan Huang, David F. Chernoff
openaire   +2 more sources

Cloud–Cloud Collision and Cluster Formation in the W5-NW Complex

The Astronomical Journal
We present a detailed structural and gas kinematic study of the star-forming complex W5-NW. A cloud–cloud collision scenario unravels with evidence of collision-induced star and cluster formation.
Namitha Issac, Anindya Saha, Saanika Choudhary, Aakash Chaudhary, Anandmayee Tej, Hong-Li Liu, Tie Liu, Maheswar Gopinathan   +7 more
doaj   +1 more source

QPEs from EMRI Debris Streams Impacting Accretion Disks in Galactic Nuclei

The Astrophysical Journal
Quasi-periodic eruption (QPE) sources in galactic nuclei are often associated with a stellar object orbiting a supermassive black hole with an hours to days period, which is brought in as an extreme mass-ratio inspiral (EMRI).
Itai Linial, Brian D. Metzger, Eliot Quataert   +2 more
doaj   +1 more source