Search arXiv⌕ Search

arXiv · astro-ph/0110342

Infrared Views of the TW Hya Disk

Abstract

The face-on disk around TW Hya is imaged in scattered light at wavelengths of 1.1 and 1.6 micron using the coronagraph in the Near Infrared Camera and Multi Object Spectrometer aboard the Hubble Space Telescope. Stellar light scattered from the optically thick dust disk is seen from 20-230 AU. The surface brightness declines as a power law of r^(-2.6+/-0.1) between 45 and 150 AU. The scattering profile indicates that the disk is flared, not geometrically flat. The disk, while spatially unresolved in thermal radiation at wavelengths of 12 and 18 micron in observations from the W. M. Keck Observatory, shows amorphous and crystalline silicate emission in its spectrum. A disk with silicate grains of a ~1 micron in size in its surface layers can explain the shape of the mid-infrared spectrum. Much larger grains in the disk interior are necessary to fit the millimeter-wave spectral energy distribution, and hence grain growth from an original interstellar size population may have occurred.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

A. J. Weinberger, E. E. Becklin, G. Schneider, E. I. Chiang, P. J. Lowrance, M. Silverstone, B. Zuckerman, D. C. Hines, B. A. Smith. 2001-10-15. Infrared Views of the TW Hya Disk. https://doi.org/10.1086/338076

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Cosmic Conundrums with Quantum Corrections

Darh energy was discovered over 25 years ago and we do not have an explanation of it. Dark matter comprises 95% of matter in the universe and we still don't know what it is. The Webb telescope has been finding fully formed galaxies with massive black holes millions of times the mass of the sun in the early universe and we don't have any explanation. A quantum density limitation will be used to solve these and other outstanding problems.

astro-ph↗

On binary pulsars and the force of gravity

The energy-momentum budget of the astrophysical systems can be studied by the exact local conservation equation derived by Landau and Lifshitz. We show that a similar equation is valid for the Einstein-Cartan gravity. We reanalyze a binary pulsar system using the Landau-Lifshitz conservation equation and show that the orbital period change rate can be completely understood as a curvature backreaction process. Taking into account the detailed theoretical and observational research of relativistic binary pulsar systems, especially the system of Hulse and Taylor, we conclude that general relativity and astrophysical observations rule out the existence of gravitational radiation. We comment upon the LIGO GW events and their alternative explanation, as well as the recent pulsar timing arrays data.

astro-ph↗

Oscillation frequencies and mode lifetimes in alpha Centauri A

We analyse our recently-published velocity measurements of alpha Cen A (Butler et al. 2004). After adjusting the weights on a night-by-night basis in order to optimize the window function to minimize sidelobes, we extract 42 oscillation frequencies with l=0 to 3 and measure the large and small frequency separations. We give fitted relations to these frequencies that can be compared with theoretical models and conclude that the observed scatter about these fits is due to the finite lifetimes of the oscillation modes. We estimate the mode lifetimes to be 1-2 d, substantially shorter than in the Sun.

astro-ph↗