A Caltech Library Service

The structure and dynamics of the dense cores in the Perseus molecular cloud complex

Olmi, L. and Testi, L. and Sargent, A. I. (2005) The structure and dynamics of the dense cores in the Perseus molecular cloud complex. Astronomy & Astrophysics, 431 (1). pp. 253-268. ISSN 0004-6361.

[img] PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


We have produced wide-field (≳ 0.1 deg^2) images of the molecular gas around the dense cores observed by Ladd et al. (1994) in the Perseus cloud complex in various CO (CO(1-0), ^(13)CO(1-0), C^(18)O(1-0)) and CS (CS(2-1), C^(34)S(2-1)) isotopomers, and N_2H^+(1-0), using the 16-element focal plane array operating at a wavelength of 3 mm at the Five College Radio Astronomy Observatory. We also performed mosaic observations in the N_2H^+(1-0) line and in the adjacent 3 mm continuum with the OVRO interferometer. Only within one of the observed cores we unambiguously detected a 3 mm continuum compact source with the interferometer. The single-dish large-scale maps of the densest gas, which in Perseus is concentrated within two large filamentary structures roughly aligned along a NE-SW axis, allowed us to analyse the spatial and kinematical properties of the cores and of the surrounding ambient gas. In the PER4/PER5 and PER7 regions we find that the large-scale and core velocity gradients have the same sign and similar magnitudes. In at least three cases we then find pairs of nearby cores with differences in the CS and N_2H^+ emission and in the line profile, which may have been caused by evolutionary effects. The small fraction of cores with compact continuum sources, the chemical differentiation and the inward motions observed suggest that we are observing objects in a phase preceeding the collapse and the formation of stars.

Item Type:Article
Related URLs:
URLURL TypeDescription
Sargent, A. I.0000-0002-4633-5098
Additional Information:© ESO 2005. (Received 26 March 2004 / Accepted 15 October 2004) Research at the Owens Valley Radio Observatory is supported by the National Science Foundation through NSF grant AST 96-13717. Star Formation research at Owens Valley is also supported by the NASA's Origins of Solar Systems program, grant NAGW-4030 and by the Norris Planetary Origins Project. During L.O.'s stay at the University of Puerto Rico this work was partially supported by the Puerto Rico Space Grant Consortium.
Funding AgencyGrant Number
NSFAST 96-13717
Norris Planetary Origins ProjectUNSPECIFIED
Puerto Rico Space Grant ConsortiumUNSPECIFIED
Subject Keywords:ISM: molecules -- stars: formation -- radio lines: ISM
Issue or Number:1
Record Number:CaltechAUTHORS:20170408-142009469
Persistent URL:
Official Citation:The structure and dynamics of the dense cores in the Perseus molecular cloud complex L. Olmi, L. Te ti and A. I. Sargent A&A, 431 1 (2005) 253-268 DOI:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:75925
Deposited By: 1Science Import
Deposited On:20 Apr 2017 21:41
Last Modified:03 Oct 2019 16:55

Repository Staff Only: item control page