A KOSMA 7 deg^2 13CO 2--1 & 12CO 3--2 survey of the Perseus cloud
| dc.creator | Sun, K. | |
| dc.creator | Kramer, C. | |
| dc.creator | Ossenkopf, V. | |
| dc.creator | Bensch, F. | |
| dc.creator | Stutzki, J. | |
| dc.creator | Miller, M. | |
| dc.date | 2006-01-27 | |
| dc.date | 2006-01-29 | |
| dc.date.accessioned | 2026-07-07T06:57:08Z | |
| dc.date.available | 2026-07-07T06:57:08Z | |
| dc.description | Characterizing the spatial and velocity structure of molecular clouds is a first step towards a better understanding of interstellar turbulence and its link to star formation. We present observations and structure analysis results for a large-scale (~ 7.10 deg^2) 13CO J = 2--1 and 12 CO J = 3--2 survey towards the nearby Perseus molecular cloud observed with the KOSMA 3m telescope. We study the spatial structure of line-integrated and velocity channel maps, measuring the $Δ$-variance as a function of size scale. We determine the spectral index $β$ of the corresponding power spectrum and study its variation across the cloud and across the lines. We find that the spectra of all CO line-integrated maps of the whole complex show the same index, $β$ ~ 3.1, for scales between about 0.2 and 3pc, independent of isotopomer and rotational transition. A complementary 2MASS map of optical extinction shows a noticeably smaller index of 2.6. In contrast to the overall region, the CO maps of individual subregions show a significant variation of $β$. The 12CO 3--2 data provide e.g. a spread of indices between 2.9 in L1455 and 3.5 in NGC1333. In general, active star forming regions show a larger power-law exponent. We find that the $Δ$-variance spectra of individual velocity channel maps are very sensitive to optical depth effects clearly indicating self-absorption in the densest regions. When studying the dependence of the channel-map spectra as a function of the velocity channel width, the expected systematic increase of the spectral index with channel width is only detected in the blue line wings.This could be explained by a filamentary, pillar-like structure which is left at low velocities while the overall molecular gas is swept up by a supernova shock wave. | |
| dc.description | 11 pages, 10 figures, accepted by A&A | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0601650 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0601650 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/106856 | |
| dc.subject | Astrophysics | |
| dc.title | A KOSMA 7 deg^2 13CO 2--1 & 12CO 3--2 survey of the Perseus cloud | |
| dc.type | text |