Friday, 23 April 2010
Dust in DLAs
Frank & Peroux (http://uk.arxiv.org/abs/1004.3298) has done a study of dust attenuation in damped-Lya absorbers from the SDSS DR7. Using 676 absorbers and a comparison sample of QSOs they manage to put stringent constraints on the amount of dust attenuation in the Lya absorbers and find that on average they have <0.01 in E(B-V). What is nice is that they show that if they use the same selection techniques as others have used in the past, they do recover their detections - so their conclusion is that the average DLA has very little dust but that some specially selected subsamples do show some.