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Title: PROPERTIES OF THE COOLEST DWARFS

Abstract

Eleven years after the discovery of the first T dwarf, we have a population of ultracool L and T dwarfs that is large enough to show a range of atmospheric properties, as well as model atmospheres advanced enough to study these properties in detail. Since the last Cool Stars meeting, there have been observational developments which aid in these studies. they present recent mid-infrared photometry and spectroscopy from the Spitzer Space Telescope which confirms the prevalence of vertical mixing in the atmospheres of L and T dwarfs. Hence, the 700 K to 2200 K L and t dwarf photspheres require a large number of parameters for successful modeling: effective temperature, gravity, metallicity, grain sedimentation and vertical mixing efficiency. They also describe initial results of a search for ultracool dwarfs in the UKIRT Infrared Deep Sky Survey, and present the latest T dwarf found to date. They conclude with a discussion of the definition of the later-than-T spectral type, the Y dwarf.

Authors:
 [1];  [2];  [2];  [2];  [2];  [2];  [2];  [2];  [2];  [2]
  1. Los Alamos National Laboratory
  2. NON LANL
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
OSTI Identifier:
1000761
Report Number(s):
LA-UR-07-0399
TRN: US201101%%544
DOE Contract Number:
AC52-06NA25396
Resource Type:
Conference
Resource Relation:
Conference: 14TH CAMBRIDGE WORKSHOP ON COOL STARS, STELLAR SYSTEMS, AN ; 200611 ; PASADENA
Country of Publication:
United States
Language:
English
Subject:
71; EFFICIENCY; PHOTOMETRY; SEDIMENTATION; SIMULATION; SKY; SPECTROSCOPY; STARS; SUN; TELESCOPES; DWARF STARS

Citation Formats

SAUMON, DIDIER, LEGGETT, SANDY K., FREEDMAN, RICHARD S., GEBALLE, THOMAS R., GOLIMOWSKI, DAVID A., LODIEU, NICOLAS, MARLEY, MARK S., STEPHENS, DENISE, PINFIELD, DAVID J., and WARREN, STEPHEN J. PROPERTIES OF THE COOLEST DWARFS. United States: N. p., 2007. Web.
SAUMON, DIDIER, LEGGETT, SANDY K., FREEDMAN, RICHARD S., GEBALLE, THOMAS R., GOLIMOWSKI, DAVID A., LODIEU, NICOLAS, MARLEY, MARK S., STEPHENS, DENISE, PINFIELD, DAVID J., & WARREN, STEPHEN J. PROPERTIES OF THE COOLEST DWARFS. United States.
SAUMON, DIDIER, LEGGETT, SANDY K., FREEDMAN, RICHARD S., GEBALLE, THOMAS R., GOLIMOWSKI, DAVID A., LODIEU, NICOLAS, MARLEY, MARK S., STEPHENS, DENISE, PINFIELD, DAVID J., and WARREN, STEPHEN J. Thu . "PROPERTIES OF THE COOLEST DWARFS". United States. doi:. https://www.osti.gov/servlets/purl/1000761.
@article{osti_1000761,
title = {PROPERTIES OF THE COOLEST DWARFS},
author = {SAUMON, DIDIER and LEGGETT, SANDY K. and FREEDMAN, RICHARD S. and GEBALLE, THOMAS R. and GOLIMOWSKI, DAVID A. and LODIEU, NICOLAS and MARLEY, MARK S. and STEPHENS, DENISE and PINFIELD, DAVID J. and WARREN, STEPHEN J.},
abstractNote = {Eleven years after the discovery of the first T dwarf, we have a population of ultracool L and T dwarfs that is large enough to show a range of atmospheric properties, as well as model atmospheres advanced enough to study these properties in detail. Since the last Cool Stars meeting, there have been observational developments which aid in these studies. they present recent mid-infrared photometry and spectroscopy from the Spitzer Space Telescope which confirms the prevalence of vertical mixing in the atmospheres of L and T dwarfs. Hence, the 700 K to 2200 K L and t dwarf photspheres require a large number of parameters for successful modeling: effective temperature, gravity, metallicity, grain sedimentation and vertical mixing efficiency. They also describe initial results of a search for ultracool dwarfs in the UKIRT Infrared Deep Sky Survey, and present the latest T dwarf found to date. They conclude with a discussion of the definition of the later-than-T spectral type, the Y dwarf.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jan 18 00:00:00 EST 2007},
month = {Thu Jan 18 00:00:00 EST 2007}
}

Conference:
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