_version_ 1866915768434688000
author Hardiman, Caitlyn
Pinte, Christophe
Price, Daniel J.
Hilder, Thomas
Hammond, Iain
Danilovich, Taïssa
Andrews, Sean M.
Teague, Richard
Rosotti, Giovanni
Flock, Mario
Cataldi, Gianni
Bae, Jaehan
Barraza-Alfaro, Marcelo
Benisty, Myriam
Cuello, Nicolás
Curone, Pietro
Czekala, Ian
Facchini, Stefano
Fasano, Daniele
Fukagawa, Misato
Galloway-Sprietsma, Maria
Garg, Himanshi
Hall, Cassandra
Huang, Jane
Ilee, John D.
Izquierdo, Andres F.
Kanagawa, Kazuhiro
Lesur, Geoffroy
Lodato, Giuseppe
Longarini, Cristiano
Loomis, Ryan
Menard, Francois
Orihara, Ryuta
Stadler, Jochen
Yen, Hsi-Wei
Wafflard-Fernandez, Gaylor
Wilner, David J.
Winter, Andrew J.
Wölfer, Lisa
Yoshida, Tomohiro C.
Zawadzki, Brianna
author_facet Hardiman, Caitlyn
Pinte, Christophe
Price, Daniel J.
Hilder, Thomas
Hammond, Iain
Danilovich, Taïssa
Andrews, Sean M.
Teague, Richard
Rosotti, Giovanni
Flock, Mario
Cataldi, Gianni
Bae, Jaehan
Barraza-Alfaro, Marcelo
Benisty, Myriam
Cuello, Nicolás
Curone, Pietro
Czekala, Ian
Facchini, Stefano
Fasano, Daniele
Fukagawa, Misato
Galloway-Sprietsma, Maria
Garg, Himanshi
Hall, Cassandra
Huang, Jane
Ilee, John D.
Izquierdo, Andres F.
Kanagawa, Kazuhiro
Lesur, Geoffroy
Lodato, Giuseppe
Longarini, Cristiano
Loomis, Ryan
Menard, Francois
Orihara, Ryuta
Stadler, Jochen
Yen, Hsi-Wei
Wafflard-Fernandez, Gaylor
Wilner, David J.
Winter, Andrew J.
Wölfer, Lisa
Yoshida, Tomohiro C.
Zawadzki, Brianna
contents Turbulence is expected to transport angular momentum and drive mass accretion in protoplanetary disks. One way to directly measure turbulent motion in disks is through molecular line broadening. DM Tau is one of only a few disks with claimed detection of nonthermal line broadening of 0.25cs-0.33cs, where cs is the sound speed. Using the radiative transfer code mcfost within a Bayesian inference framework that evaluates over five million disk models to efficiently sample the parameter space, we fit high-resolution (0.15", 28 m s-1) 12CO J = 3-2 observations of DM Tau from the exoALMA Large Program. This approach enables us to simultaneously constrain the disk structure and kinematics, revealing a significant nonthermal contribution to the line width of ~0.4cs, inconsistent with purely thermal motions. Using the CO-based disk structure as a starting point, we reproduce the CS J = 7-6 emission well, demonstrating that the CS (which is more sensitive to nonthermal motions than CO) agrees with the turbulence inferred from the CO fit. Establishing a well-constrained background disk model further allows us to identify residual structures in the moment maps that deviate from the expected emission, revealing localized perturbations that may trace forming planets. This framework provides a powerful general approach for extracting disk structure and nonthermal broadening directly from molecular line data and can be applied to other disks with high-quality observations.
format Preprint
id arxiv_https___arxiv_org_abs_2602_01620
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle exoALMA XIX: Confirmation of Non-thermal Line Broadening in the DM Tau Protoplanetary Disk
Hardiman, Caitlyn
Pinte, Christophe
Price, Daniel J.
Hilder, Thomas
Hammond, Iain
Danilovich, Taïssa
Andrews, Sean M.
Teague, Richard
Rosotti, Giovanni
Flock, Mario
Cataldi, Gianni
Bae, Jaehan
Barraza-Alfaro, Marcelo
Benisty, Myriam
Cuello, Nicolás
Curone, Pietro
Czekala, Ian
Facchini, Stefano
Fasano, Daniele
Fukagawa, Misato
Galloway-Sprietsma, Maria
Garg, Himanshi
Hall, Cassandra
Huang, Jane
Ilee, John D.
Izquierdo, Andres F.
Kanagawa, Kazuhiro
Lesur, Geoffroy
Lodato, Giuseppe
Longarini, Cristiano
Loomis, Ryan
Menard, Francois
Orihara, Ryuta
Stadler, Jochen
Yen, Hsi-Wei
Wafflard-Fernandez, Gaylor
Wilner, David J.
Winter, Andrew J.
Wölfer, Lisa
Yoshida, Tomohiro C.
Zawadzki, Brianna
Earth and Planetary Astrophysics
Turbulence is expected to transport angular momentum and drive mass accretion in protoplanetary disks. One way to directly measure turbulent motion in disks is through molecular line broadening. DM Tau is one of only a few disks with claimed detection of nonthermal line broadening of 0.25cs-0.33cs, where cs is the sound speed. Using the radiative transfer code mcfost within a Bayesian inference framework that evaluates over five million disk models to efficiently sample the parameter space, we fit high-resolution (0.15", 28 m s-1) 12CO J = 3-2 observations of DM Tau from the exoALMA Large Program. This approach enables us to simultaneously constrain the disk structure and kinematics, revealing a significant nonthermal contribution to the line width of ~0.4cs, inconsistent with purely thermal motions. Using the CO-based disk structure as a starting point, we reproduce the CS J = 7-6 emission well, demonstrating that the CS (which is more sensitive to nonthermal motions than CO) agrees with the turbulence inferred from the CO fit. Establishing a well-constrained background disk model further allows us to identify residual structures in the moment maps that deviate from the expected emission, revealing localized perturbations that may trace forming planets. This framework provides a powerful general approach for extracting disk structure and nonthermal broadening directly from molecular line data and can be applied to other disks with high-quality observations.
title exoALMA XIX: Confirmation of Non-thermal Line Broadening in the DM Tau Protoplanetary Disk
topic Earth and Planetary Astrophysics
url https://arxiv.org/abs/2602.01620