The observational anatomy of externally photoevaporating planet-forming discs - I. Atomic carbon
File(s)2001.05004.pdf (5.76 MB)
Accepted version
OA Location
Author(s)
Haworth, Thomas J
Owen, James E
Type
Journal Article
Abstract
We demonstrate the utility of C I as a tracer of photoevaporative winds that are being driven from discs by their ambient UV environment. Commonly observed CO lines only trace these winds in relatively weak UV environments and are otherwise dissociated in the wind at the intermediate to high UV fields that most young stars experience. However, C I traces unsubtle kinematic signatures of a wind in intermediate UV environments (∼1000 G0) and can be used to place constraints on the kinematics and temperature of the wind. In C I position–velocity (PV) diagrams external photoevaporation results in velocities that are faster than those from Keplerian rotation alone, as well as emission from quadrants of PV space in which there would be no Keplerian emission. This is independent of viewing angle because the wind has components that are perpendicular to the azimuthal rotation of the disc. At intermediate viewing angles (∼30–60°) moment 1 maps also exhibit a twisted morphology over large scales (unlike other processes that result in twists, which are typically towards the inner disc). C I is readily observable with ALMA, which means that it is now possible to identify and characterize the effect of external photoevaporation on planet-forming discs in intermediate UV environments.
Date Issued
2020-03-01
Date Acceptance
2020-01-13
Citation
Monthly Notices of the Royal Astronomical Society, 2020, 492 (4), pp.5030-5040
ISSN
0035-8711
Publisher
Oxford University Press (OUP)
Start Page
5030
End Page
5040
Journal / Book Title
Monthly Notices of the Royal Astronomical Society
Volume
492
Issue
4
Copyright Statement
© 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This is a pre-copy-editing, author-produced version of an article accepted for publication in Monthly Notices following peer review. The definitive publisher-authenticated version Thomas J Haworth, James E Owen, The observational anatomy of externally photoevaporating planet-forming discs – I. Atomic carbon, Monthly Notices of the Royal Astronomical Society, Volume 492, Issue 4, March 2020, Pages 5030–5040 is available online at: https://doi.org/10.1093/mnras/staa151
Sponsor
The Royal Society
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000518148000033&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Grant Number
UF150412
Subjects
Science & Technology
Physical Sciences
Astronomy & Astrophysics
accretion, accretion discs
hydrodynamics
planets and satellites: formation
protoplanetary discs
circumstellar matter
photodissociation region (PDR)
CIRCUMSTELLAR DISKS
PROTOPLANETARY DISCS
MASS-LOSS
RADIATION
ULTRAVIOLET
DRIVEN
NEBULA
CODE
Publication Status
Published
Date Publish Online
2020-01-21