Distances to Dark Clouds: Comparing Extinction Distances to Maser Parallax Distances

Дата и время публикации : 2012-04-24T20:00:25Z

Авторы публикации и институты :
Jonathan B. Foster
Joseph J. Stead
Robert A. Benjamin
Melvin G. Hoare
James M. Jackson

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: Accepted to ApJ. 14 pages and 10 figures plus eight additional pages of figures. Full resolution version is available at http://people.bu.edu/jbfoster/papers/Foster_2012_ExtinctionDistances.pdf
Первичная категория: astro-ph.GA

Все категории : astro-ph.GA

Краткий обзор статьи: We test two different methods of using near-infrared extinction to estimate distances to dark clouds in the first quadrant of the Galaxy using large near infrared (2MASS and UKIDSS) surveys. VLBI parallax measurements of masers around massive young stars provide the most direct and bias-free measurement of the distance to these dark clouds. We compare the extinction distance estimates to these maser parallax distances. We also compare these distances to kinematic distances, including recent re-calibrations of the Galactic rotation curve. The extinction distance methods agree with the maser parallax distances (within the errors) between 66% and 100% of the time (depending on method and input survey) and between 85% and 100% of the time outside of the crowded Galactic center. Although the sample size is small, extinction distance methods reproduce maser parallax distances better than kinematic distances; furthermore, extinction distance methods do not suffer from the kinematic distance ambiguity. This validation gives us confidence that these extinction methods may be extended to additional dark clouds where maser parallaxes are not available.

Category: Physics