Results 51 to 60 of about 2,982 (223)

Debris Disks Can Contaminate Mid-infrared Exoplanet Spectra: Evidence for a Circumstellar Debris Disk around Exoplanet Host WASP-39

The Astrophysical Journal Letters
The signal from a transiting planet can be diluted by astrophysical contamination. In the case of circumstellar debris disks, this contamination could start in the mid-infrared and vary as a function of wavelength, which would then change the observed ...
Laura Flagg, Alycia J. Weinberger, Taylor J. Bell, Luis Welbanks, Giuseppe Morello, Diana Powell, Jacob L. Bean, Jasmina Blecic, Nicolas Crouzet, Peter Gao, Julie Inglis, James Kirk, Mercedes López-Morales, Karan Molaverdikhani, Nikolay Nikolov, Apurva V. Oza, Benjamin V. Rackham, Seth Redfield, Shang-Min Tsai, Ray Jayawardhana, Laura Kreidberg, Matthew C. Nixon, Kevin B. Stevenson, Jake D. Turner   +23 more
doaj   +1 more source

The Warped Circumstellar Disk of HD 100546

The Astrophysical Journal, 2006
We propose that the two armed spiral features seen in visible Hubble Space Telescope images of scattered light in HD100546's circumstellar disk are caused by the illumination of a warped outer disk. A tilt of 6-15 degrees from the symmetry plane can cause the observed surface brightness variations providing the disk is very twisted (highly warped) at ...
openaire   +2 more sources

JWST Imaging of the Closest Globular Clusters—VI. The Lowest‐Mass Objects in M 4 and the Galactic Bulge

Astronomische Nachrichten, Volume 346, Issue 9, November 2025.
ABSTRACT We present James Webb Space Telescope observations of M 4—the closest globular cluster—that probe the lower Main Sequence down to the hydrogen‐burning limit. The unveiled stellar sequence reaches much fainter luminosities than previously possible, revealing a few extremely red objects that are consistent with brown dwarfs as cool as Teff∼1000K$
L. R. Bedin, R. Gerasimov, A. Calamida, M. Libralato, M. Scalco, D. Nardiello, M. Griggio, D. Apai, J. Anderson, A. Bellini, A. Burgasser   +10 more
wiley   +1 more source

Interaction of a Supernova with a Circumstellar Disk [PDF]

The Astrophysical Journal, 2018
Abstract Interaction between a supernova (SN) ejecta and a dense circumstellar medium (CSM) can power a luminous light curve and create narrow emission lines in the spectra. While theoretical studies of interaction often assume a spherically symmetric CSM, there are observational indications that the gas surrounding some SNe has a disk ...
Austin T. McDowell, Paul C. Duffell, Daniel Kasen   +2 more
openaire   +2 more sources

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

Planet–planet scattering in circumstellar gas disks [PDF]

Astronomy and Astrophysics, 2010
Astronomy and Astrophysics Letters, in ...
MARZARI, FRANCESCO, BARUTEAU, C, SCHOLL, H.   +2 more
openaire   +2 more sources

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

Chemical Models of Circumstellar Disks [PDF]

Symposium - International Astronomical Union, 2000
We investigate the evolution of molecular abundances in circumstellar disks around young stars via numerical simulations. The results are compared with the composition of comets and radio observations of protoplanetary disks. First, we consider the molecular evolution in the midplane of the disk.
Yuri Aikawa, Eric Herbst
openaire   +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

Projection of circumstellar disks on their environments [PDF]

Astronomy & Astrophysics, 2005
16 pages, 12 figures, accepted for publication in Astronomy & ...
Pontoppidan, K.M., Dullemond, C.P.
openaire   +4 more sources