English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We present CO(J=3-2) emission observations with the Atacama SubmillimeterTelescope Experiment (ASTE) toward the 5' x 5' (or 6.6 x 6.6 kpc at thedistance D = 4.5 Mpc) region of the nearby barred spiral galaxy M 83. Wesuccessfully resolved the major structures, i.e., the nuclear starburst region,bar, and inner spiral arms in CO(J=3-2) emission at a resolution of 22'' (or480 pc), showing a good spatial coincidence between CO(J=3-2) and 6 cmcontinuum emissions. We found a global CO(J=3-2) luminosity L'_CO(3-2) of 5.1 x10^8 K km s^-1 pc^2 within the observed region. We also found L'_CO(3-2) in thedisk region (0.5 < r < 3.5 kpc) of 4.2 x 10^8 K km s^-1 pc^2, indicating thatCO(J=3-2) emission in the disk region significantly contributes to the globalL'_CO(3-2). From a comparison of a CO(J=3-2) data with CO(J=1-0) intensitiesmeasured with Nobeyama 45-m telescope, we found that the radial profile ofCO(J=3-2)/CO(J=1-0) integrated intensity ratio R_3-2/1-0 is almost unity in thecentral region (r < 0.25 kpc), whereas it drops to a constant value, 0.6--0.7,in the disk region. The radial profile of star formation efficiencies (SFEs),determined from 6 cm radio continuum and CO(J=1-0) emission, shows the sametrend as that of R_3-2/1-0. At the bar-end (r ~ 2.4 kpc), the amounts ofmolecular gas and the massive stars are enhanced when compared with other diskregions, whereas there is no excess of R_3-2/1-0 and SFE in that region. Thismeans that a simple summation of the star forming regions at the bar-end andthe disk cannot reproduce the nuclear starburst of M 83, implying that thespatial variation of the dense gas fraction traced by R_3-2/1-0 governs thespatial variation of SFE in M 83.

ASTE CO (3–2) Observations of the Barred Spiral Galaxy M 83: I. Correlation between CO (3–2)/CO (1–0) Ratios and Star Formation Efficiencies