dc.contributor.author |
Tata, R |
|
dc.contributor.author |
Martin, E. L |
|
dc.contributor.author |
Sengupta, S |
|
dc.contributor.author |
Phan-Bao, N |
|
dc.contributor.author |
Zapatero Osorio, M. R |
|
dc.contributor.author |
Bouy, H |
|
dc.date.accessioned |
2009-11-05T13:59:57Z |
|
dc.date.available |
2009-11-05T13:59:57Z |
|
dc.date.issued |
2009-12 |
|
dc.identifier.citation |
Astronomy and Astrophysics, Vol. 508, No. 3, pp. 1423 - 1427 |
en |
dc.identifier.issn |
0004-6361 |
|
dc.identifier.uri |
http://hdl.handle.net/2248/4899 |
|
dc.description |
Open Access |
|
dc.description.abstract |
Aims.Recent studies have detected linear polarization in L dwarfs in the optical I band. Theoretical models have been developed to explain this polarization. These models predict higher polarization at shorter wavelengths. We discuss the polarization in the R and I band of 4 ultra cool dwarfs. Methods.We report linear polarization measurements of 4 ultra cool dwarfs in the R and I bands using the Intermediate dispersion Spectrograph and Imaging System (ISIS) mounted on the 4.2m William Herschel Telescope (WHT). Results.As predicted by theoretical models, we find a higher degree of polarization in the R band when compared to polarization in the I band for 3/4 of these ultra cool dwarfs. This suggests that dust scattering asymmetry is caused by oblateness >.We also show how these measurements fit the theoretical models. A case for variability of linear polarization is found, which suggests the presence of randomly distributed dust clouds. We also discuss one case for the presence of a cold debris disk. |
en |
dc.language.iso |
en |
en |
dc.publisher |
European Space Agency |
en |
dc.relation.uri |
http://dx.doi.org/10.1051/0004-6361/200911830 |
|
dc.rights |
© European Space Agency |
en |
dc.subject |
Polarization |
en |
dc.subject |
Atmospheric Effects |
en |
dc.subject |
Brown Dwarfs |
en |
dc.subject |
Stars: Low-Mass |
en |
dc.title |
Optical linear polarization in ultra cool dwarfs: A tool to probe dust in the ultra cool dwarf atmospheres |
en |
dc.type |
Article |
en |