We present a near-infrared extinction map of a large region in the sky (~ 3500 deg2) in the general directions of Taurus, Perseus, and Aries. The map has been obtained using robust and optimal methods to map dust column density at near-infrared wavelengths (Nicer, described in Lombardi & Alves 2001, A&A, 377, 1023 and Nicest, described in Lombardi 2009, A&A, 493, 735) toward ~23 million stars from the Two Micron All Sky Survey (2MASS) point source catalog. We measure extinction as low as AK = 0.04 mag with a 1-σ significance, and a resolution of 2.5 arcmin in our map. A 250 deg2 section of our map encompasses the Taurus, Perseus, and California molecular cloud complexes. We determine the distances of the clouds by comparing the observed density of foreground stars with the prediction of galactic models, and we obtain results that are in excellent agreement with recent VLBI parallax measurements. We characterize the large-scale structure of the map and find a ~ 25° × 15° region close to the galactic plane (l ~ 135°, b ~ -14°) with small extinction (AK < 0.04 mag); we name this region the Perseus-Andromeda hole. We find that over the region that encompasses the Taurus, Perseus, and California clouds the column density measurements below AK < 0.2 mag are perfectly described by a log-normal distribution, and that a significant deviation is observed at larger extinction values. If turbulence models are invoked to justify the log-normal distribution, the observed departure could be interpreted as the result of the effect of gravity that acts on the cores of the clouds. Finally, we investigate the cloud structure function, and show that significant deviations from the results predicted by turbulent models are observed in at least one cloud. 


2MASS wide field extinction maps. III. The Taurus, Perseus, and California cloud complexes / M. Lombardi, C. J. Lada, J. Alves. - In: ASTRONOMY & ASTROPHYSICS. - ISSN 0004-6361. - 512:10(2010 Mar), pp. A67.1-A67.14. [10.1051/0004-6361/200912670]

2MASS wide field extinction maps. III. The Taurus, Perseus, and California cloud complexes

M. Lombardi
Primo
;
2010

Abstract

We present a near-infrared extinction map of a large region in the sky (~ 3500 deg2) in the general directions of Taurus, Perseus, and Aries. The map has been obtained using robust and optimal methods to map dust column density at near-infrared wavelengths (Nicer, described in Lombardi & Alves 2001, A&A, 377, 1023 and Nicest, described in Lombardi 2009, A&A, 493, 735) toward ~23 million stars from the Two Micron All Sky Survey (2MASS) point source catalog. We measure extinction as low as AK = 0.04 mag with a 1-σ significance, and a resolution of 2.5 arcmin in our map. A 250 deg2 section of our map encompasses the Taurus, Perseus, and California molecular cloud complexes. We determine the distances of the clouds by comparing the observed density of foreground stars with the prediction of galactic models, and we obtain results that are in excellent agreement with recent VLBI parallax measurements. We characterize the large-scale structure of the map and find a ~ 25° × 15° region close to the galactic plane (l ~ 135°, b ~ -14°) with small extinction (AK < 0.04 mag); we name this region the Perseus-Andromeda hole. We find that over the region that encompasses the Taurus, Perseus, and California clouds the column density measurements below AK < 0.2 mag are perfectly described by a log-normal distribution, and that a significant deviation is observed at larger extinction values. If turbulence models are invoked to justify the log-normal distribution, the observed departure could be interpreted as the result of the effect of gravity that acts on the cores of the clouds. Finally, we investigate the cloud structure function, and show that significant deviations from the results predicted by turbulent models are observed in at least one cloud. 

Dust; Extinction; ISM: clouds; ISM: individual objects: Taurus molecular complex; ISM: structure; Methods: statistical
Settore FIS/05 - Astronomia e Astrofisica
mar-2010
Article (author)
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/150748
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 110
  • ???jsp.display-item.citation.isi??? 109
social impact