Results 51 to 60 of about 17,073 (217)

Improving the thin-disk models of circumstellar disk evolution. The 2+1-dimensional model

, 2017
Circumstellar disks of gas and dust are naturally formed from contracting pre-stellar molecular cores during the star formation process. To study various dynamical and chemical processes that take place in circumstellar disks prior to their dissipation ...
Pavlyuchenkov, Yaroslav N., Vorobyov, Eduard I.   +1 more
core   +2 more sources

Circumstellar Disks and Star Formation [PDF]

Highlights of Astronomy, 1992
Results from the IRAS satellite showed that many pre-main sequence stars exhibited unexpectedly large fluxes in the infrared spectral region. Several studies have shown that the simplest and most satisfying explanation of this excess emission is that it arises in optically-thick, dusty, circumstellar disks (Rucinski 1985; Adams, Lada, and Shu 1987 ...
L. Hartmann, M. Gomez, S.J. Kenyon
openaire   +1 more source

JWST Imaging of the Closest Globular Clusters—V. The White Dwarfs Cooling Sequence of M4

Astronomische Nachrichten, Volume 346, Issue 2, February 2025.
ABSTRACT We combine infrared (IR) observations collected by the James Webb Space Telescope with optical deep images by the Hubble Space Telescope taken ~20 years earlier to compute proper‐motion membership for the globular cluster (GC) M4 (NGC 6121) along its entire white dwarf (WD) cooling sequence (CS).
Luigi R. Bedin, Mattia Libralato, Maurizio Salaris, Domenico Nardiello, Michele Scalco, Massimo Griggio, Jay Anderson, Pierre Bergeron, Andrea Bellini, Roman Gerasimov, Adam J. Burgasser, Daniel Apai   +11 more
wiley   +1 more source

Vertical Structure of Gas and Dust in Four Debris Disks

The Astrophysical Journal
We present high-spectral-resolution M -band spectra from iSHELL on NASA’s Infrared Telescope Facility along the line of sight to the debris disk host star HD 32297. We also present a Gemini Planet Imager H -band polarimetric image of the HD 131488 debris
Kadin Worthen, Christine H. Chen, Sean D. Brittain, Cicero X. Lu, Isabel Rebollido, Aoife Brennan, Luca Matrà, Carl Melis, Timoteo Delgado, Aki Roberge, Johan Mazoyer   +10 more
doaj   +1 more source

Takeout and Delivery: Erasing the Dusty Signature of Late-stage Terrestrial Planet Formation

The Astrophysical Journal, 2023
The formation of planets like Earth is expected to conclude with a series of late-stage giant impacts that generate warm dusty debris, the most anticipated visible signpost of terrestrial planet formation in progress.
Joan R. Najita, Scott J. Kenyon
doaj   +1 more source

XMM‐Newton Observations of the Peculiar Be X‐Ray Binary A0538‐66

Astronomische Nachrichten, Volume 346, Issue 1, January 2025.
ABSTRACT A0538‐66 is a neutron star/Be x‐ray binary located in the Large Magellanic Cloud and, since its discovery in the 70s, it showed a peculiar behavior that makes it a unique object in the high‐mass x‐ray binaries scene: the extremely eccentric orbit (e=0.72$$ e=0.72 $$), the short spin period of the neutron star (P=69$$ P=69 $$ ms), the episodes ...
Michela Rigoselli, Caterina Tresoldi, Lorenzo Ducci, Sandro Mereghetti   +3 more
wiley   +1 more source

MIRI MRS Observations of β Pictoris. I. The Inner Dust, the Planet, and the Gas

The Astrophysical Journal
We present JWST MIRI Medium Resolution Spectrograph (MRS) observations of the β Pictoris system. We detect an infrared excess from the central unresolved point source from 5 to 7.5 μ m which is indicative of dust within the inner ∼7 au of the system.
Kadin Worthen, Christine H. Chen, David R. Law, Cicero X. Lu, Kielan Hoch, Yiwei Chai, G. C. Sloan, B. A. Sargent, Jens Kammerer, Dean C. Hines, Isabel Rebollido, William Balmer, Marshall D. Perrin, Dan M. Watson, Laurent Pueyo, Julien H. Girard, Carey M. Lisse, Christopher C. Stark   +17 more
doaj   +1 more source

Scattered Radiation of Protoplanetary Disks

Universe, 2022
Scattered radiation of circumstellar (CS) dust plays an important role in the physics of young stars. Its observational manifestations are various but more often they are connected with the appearance of intrinsic polarization in young stars and their CS
Vladimir P. Grinin, Larisa V. Tambovtseva   +1 more
doaj   +1 more source

Toward an efficient second‐order method for computing the surface gravitational potential on spherical‐polar meshes

Astronomische Nachrichten, Volume 345, Issue 8, October 2024.
Abstract Astrophysical accretion discs that carry a significant mass compared with their central object are subject to the effect of self‐gravity. In the context of circumstellar discs, this can, for instance, cause fragmentation of the disc gas, and—under suitable conditions—lead to the direct formation of gas‐giant planets.
Oliver Gressel, Udo Ziegler
wiley   +1 more source

Magnetic fields in circumstellar disks: The potential of Zeeman observations

, 2017
Context. Recent high angular resolution polarimetric continuum observations of circumstellar disks provide new insights into their magnetic field. However, direct constraints are limited to the plane of sky component of the magnetic field.
Brauer, R., Flock, M., Wolf, S.
core   +1 more source