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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

This paper presents observations of a protoplanetary disk around Herbig Aestar HD 163296 in 12CO (J=1-0), 12CO (J=3-2), 13CO (J=1-0), and 13CO (J=3-2)emission lines. Double-peaked emission profiles originating from the rotatingcircumstellar disk were detected in all the lines. The disk parameters wereestimated from model calculation in which the radial distribution oftemperature or surface density inside the disk has a power-law form. Thesurface density should be sufficiently high so that the disk is optically thickfor all the CO lines, as discussed in previous studies based on interferometricobservations. The temperature and outer radius of the disk were also confirmedto be consistent with the previous results. Taking advantage of difference inposition of the photosphere among the CO lines, we revealed temperaturedistribution in vertical direction. The temperature of 12CO (J=3-2) emittingregion is about twice higher than that of any other CO emitting region; theformer is about 59 K while the latter is about 31 K at 100 AU from the centralstar, suggesting that there are at least two distinct temperature regions. Thebest fit temperature for 13CO (J=1-0) that should trace the deepest region ofthe disk is even lower, implying that there is also a different temperatureregion in deep inside of the disk. Such vertical temperature distribution in adisk was identified both in T Tauri and Herbig Ae stars (e.g., DM Tau, AB Aur,and HD 31648), and this should be a common feature in protoplanetary disks.

Thermal Structure of a Protoplanetary Disk around HD163296: A Study of Vertical Temperature Distribution by CO Emission Lines