2006/04/11 by D. Froebrich, Dirk Froebrich, C. del Burgo +1 · 20 citations
Physics and Astronomy · #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Extinction (optical mineralogy) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Optics #Physics #Population #Sky #Star formation #Stars #Stellar population #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2006.10436.x
published in Monthly Notices of the Royal Astronomical Society 369(4), 1901-1910 (Oxford University Press) · 10 pages, 9 figures, 1 table, accepted for publication in MNRAS
arxiv created 2006/04/11 · openalex publication_date 2006/05/26 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The near-infrared (NIR) extinction power-law index (β) and its uncertainty is derived from three different techniques based on star counts, colour excess and a combination of them. We have applied these methods to Two Micron All Sky Survey (2MASS) data to determine maps of β and NIR extinction of the small cloud IC 1396 W. The combination of star counts and colour excess results in the most reliable method to determine β. It is found that the use of the correct β map to transform colour excess values into extinction is fundamental for column density profile analysis of clouds. We describe how artificial photometric data, based on the model of stellar population synthesis of the Galaxy, can be used to estimate uncertainties and derive systematic effects of the extinction methods presented here. We find that all colour excess based extinction determination methods are subject to small but systematic offsets, which do not affect the star counting technique. These offsets occur since stars seen through a cloud do not represent the same population as stars in an extinction-free control field.