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author Benisty, Myriam
Izquierdo, Andres F.
Stadler, Jochen
Galloway-Sprietsma, Maria
Facchini, Stefano
Winter, Andrew J.
Bae, Jaehan
Fukagawa, Misato
Teague, Richard
Pinte, Christophe
Andrews, Sean M.
Barraza-Alfaro, Marcelo
Cataldi, Gianni
Curone, Pietro
Czekala, Ian
Fasano, Daniele
Flock, Mario
Garg, Himanshi
Huang, Jane
Ilee, John D.
Kanagawa, Kazuhiro
Lawrence, Jensen
Lesur, Geoffroy
Lodato, Giuseppe
Longarini, Cristiano
Loomis, Ryan A.
Menard, Francois
Orihara, Ryuta
Price, Daniel J.
Rosotti, Giovanni
Wafflard-Fernandez, Gaylor
Wilner, David J.
Wolfer, Lisa
Yen, Hsi-Wei
Yoshida, Tomohiro C.
Zawadzki, Brianna
author_facet Benisty, Myriam
Izquierdo, Andres F.
Stadler, Jochen
Galloway-Sprietsma, Maria
Facchini, Stefano
Winter, Andrew J.
Bae, Jaehan
Fukagawa, Misato
Teague, Richard
Pinte, Christophe
Andrews, Sean M.
Barraza-Alfaro, Marcelo
Cataldi, Gianni
Curone, Pietro
Czekala, Ian
Fasano, Daniele
Flock, Mario
Garg, Himanshi
Huang, Jane
Ilee, John D.
Kanagawa, Kazuhiro
Lawrence, Jensen
Lesur, Geoffroy
Lodato, Giuseppe
Longarini, Cristiano
Loomis, Ryan A.
Menard, Francois
Orihara, Ryuta
Price, Daniel J.
Rosotti, Giovanni
Wafflard-Fernandez, Gaylor
Wilner, David J.
Wolfer, Lisa
Yen, Hsi-Wei
Yoshida, Tomohiro C.
Zawadzki, Brianna
contents Vertical gas flows, such as winds and meridional circulations, are natural outcomes of protoplanetary disk processes and play a critical role in the earliest stages of planet formation. We analyze vertical gas motions in 14 disks as part of the exoALMA Large Program, focusing on the 12CO J=3-2 and 13CO J=3-2 emission lines. Using discminer to model the Keplerian velocity field, we extract line-of-sight velocity residuals and measure the radial and vertical components of the gas motion. Vertical motions are detected in most disks. Two types of patterns emerge: (1) oscillatory up/down flows, likely linked to instabilities, and (2) transitions from downward to upward motions that we interpret as the base of a disk wind. In most cases, the velocity amplitudes are of a few tens of m/s. Two disks, however, MWC758 and CQ Tau, show two spiral velocity features in their residual maps, red- and blue-shifted, which we interpret as vertical velocities reaching up to 350 m/s (0.7 Cs), consistent with gas motion in eccentric disks. Fast upward motions (up to 500 m/s; 1.8 Cs) is also detected in the outer disk of MWC758. Synthetic observations from (magneto)hydrodynamic simulations validate the reliability of our method. Although strong molecular winds appear to be relatively rare in 12CO and 13CO, our study shows that, when traced by deep high spectral resolution line data, protoplanetary disks exhibit ubiquitous vertical flows. However, their overall velocity structure is highly complex, preventing to identify a coherent, dominant physical mechanism driving the vertical motions across all disks, thus requiring further theoretical investigation.
format Preprint
id arxiv_https___arxiv_org_abs_2603_12861
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle exoALMA XXI: The Morphology and Dynamics of Vertical Flows
Benisty, Myriam
Izquierdo, Andres F.
Stadler, Jochen
Galloway-Sprietsma, Maria
Facchini, Stefano
Winter, Andrew J.
Bae, Jaehan
Fukagawa, Misato
Teague, Richard
Pinte, Christophe
Andrews, Sean M.
Barraza-Alfaro, Marcelo
Cataldi, Gianni
Curone, Pietro
Czekala, Ian
Fasano, Daniele
Flock, Mario
Garg, Himanshi
Huang, Jane
Ilee, John D.
Kanagawa, Kazuhiro
Lawrence, Jensen
Lesur, Geoffroy
Lodato, Giuseppe
Longarini, Cristiano
Loomis, Ryan A.
Menard, Francois
Orihara, Ryuta
Price, Daniel J.
Rosotti, Giovanni
Wafflard-Fernandez, Gaylor
Wilner, David J.
Wolfer, Lisa
Yen, Hsi-Wei
Yoshida, Tomohiro C.
Zawadzki, Brianna
Earth and Planetary Astrophysics
Vertical gas flows, such as winds and meridional circulations, are natural outcomes of protoplanetary disk processes and play a critical role in the earliest stages of planet formation. We analyze vertical gas motions in 14 disks as part of the exoALMA Large Program, focusing on the 12CO J=3-2 and 13CO J=3-2 emission lines. Using discminer to model the Keplerian velocity field, we extract line-of-sight velocity residuals and measure the radial and vertical components of the gas motion. Vertical motions are detected in most disks. Two types of patterns emerge: (1) oscillatory up/down flows, likely linked to instabilities, and (2) transitions from downward to upward motions that we interpret as the base of a disk wind. In most cases, the velocity amplitudes are of a few tens of m/s. Two disks, however, MWC758 and CQ Tau, show two spiral velocity features in their residual maps, red- and blue-shifted, which we interpret as vertical velocities reaching up to 350 m/s (0.7 Cs), consistent with gas motion in eccentric disks. Fast upward motions (up to 500 m/s; 1.8 Cs) is also detected in the outer disk of MWC758. Synthetic observations from (magneto)hydrodynamic simulations validate the reliability of our method. Although strong molecular winds appear to be relatively rare in 12CO and 13CO, our study shows that, when traced by deep high spectral resolution line data, protoplanetary disks exhibit ubiquitous vertical flows. However, their overall velocity structure is highly complex, preventing to identify a coherent, dominant physical mechanism driving the vertical motions across all disks, thus requiring further theoretical investigation.
title exoALMA XXI: The Morphology and Dynamics of Vertical Flows
topic Earth and Planetary Astrophysics
url https://arxiv.org/abs/2603.12861