_version_ 1866909723281850368
author Yang, Dongting
Liu, Hong-Li
Liu, Tie
Liu, Xunchuan
Xu, Fengwei
Qin, Sheng-Li
Tej, Anandmayee
Garay, Guido
Zhu, Lei
Mai, Xiaofeng
Jiao, Wenyu
Zhang, Siju
Dib, Sami
Stutz, Amelia M.
Palau, Aina
Sanhueza, Patricio
Zavagno, Annie
Yang, A. Y.
Tang, Xindi
Tang, Mengyao
Zhang, Yichen
Garcia, Pablo
Zhang, Tianwei
Saha, Anindya
Li, Shanghuo
Goldsmith, Paul F.
Bronfman, Leonardo
Lee, Chang Won
Taniguchi, Kotomi
Das, Swagat Ranjan
Gorai, Prasanta
Hoque, Ariful
Chen, Li
Kou, Zhiping
Zhou, Jianjun
Zhang, Yankun
Toth, L. Viktor
Baug, Tapas
Shen, Xianjin
Li, Chuanshou
Zou, Jiahang
Das, Ankan
Nazeer, Hafiz
Dewangan, L. K.
Hwang, Jihye
Chibueze, James O.
author_facet Yang, Dongting
Liu, Hong-Li
Liu, Tie
Liu, Xunchuan
Xu, Fengwei
Qin, Sheng-Li
Tej, Anandmayee
Garay, Guido
Zhu, Lei
Mai, Xiaofeng
Jiao, Wenyu
Zhang, Siju
Dib, Sami
Stutz, Amelia M.
Palau, Aina
Sanhueza, Patricio
Zavagno, Annie
Yang, A. Y.
Tang, Xindi
Tang, Mengyao
Zhang, Yichen
Garcia, Pablo
Zhang, Tianwei
Saha, Anindya
Li, Shanghuo
Goldsmith, Paul F.
Bronfman, Leonardo
Lee, Chang Won
Taniguchi, Kotomi
Das, Swagat Ranjan
Gorai, Prasanta
Hoque, Ariful
Chen, Li
Kou, Zhiping
Zhou, Jianjun
Zhang, Yankun
Toth, L. Viktor
Baug, Tapas
Shen, Xianjin
Li, Chuanshou
Zou, Jiahang
Das, Ankan
Nazeer, Hafiz
Dewangan, L. K.
Hwang, Jihye
Chibueze, James O.
contents The Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures (QUARKS) survey observed 139 infrared-bright (IR-bright) massive protoclusters at 1.3 mm wavelength with ALMA. This study investigates clump-to-core fragmentation and searches for candidate high-mass starless cores within IR-bright clumps using combined ALMA 12-m (C-2) and Atacama Compact Array (ACA) 7-m data, providing $\sim$ 1 arcsec ($\sim\rm0.02~pc$ at 3.7 kpc) resolution and $\sim\rm0.6\,mJy\,beam^{-1}$ continuum sensitivity ($\sim 0.3~M_{\odot}$ at 30 K). We identified 1562 compact cores from 1.3 mm continuum emission using getsf. Observed linear core separations ($λ_{\rm obs}$) are significantly less than the thermal Jeans length ($λ_{\rm J}$), with the $λ_{\rm obs}/λ_{\rm J}$ ratios peaking at $\sim0.2$. This indicates that thermal Jeans fragmentation has taken place within the IR-bright protocluster clumps studied here. The observed low ratio of $λ_{\rm obs}/λ_{\rm J}\ll 1$ could be the result of evolving core separation or hierarchical fragmentation. Based on associated signatures of star formation (e.g., outflows and ionized gas), we classified cores into three categories: 127 starless, 971 warm, and 464 evolved cores. Two starless cores have mass exceeding 16$\,M_{\odot}$, and represent high-mass candidates. The scarcity of such candidates suggests that competitive accretion-type models could be more applicable than turbulent core accretion-type models in high-mass star formation within these IR-bright protocluster clumps.
format Preprint
id arxiv_https___arxiv_org_abs_2508_03229
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle The ALMA-QUARKS Survey: III. Clump-to-core fragmentation and search for high-mass starless cores
Yang, Dongting
Liu, Hong-Li
Liu, Tie
Liu, Xunchuan
Xu, Fengwei
Qin, Sheng-Li
Tej, Anandmayee
Garay, Guido
Zhu, Lei
Mai, Xiaofeng
Jiao, Wenyu
Zhang, Siju
Dib, Sami
Stutz, Amelia M.
Palau, Aina
Sanhueza, Patricio
Zavagno, Annie
Yang, A. Y.
Tang, Xindi
Tang, Mengyao
Zhang, Yichen
Garcia, Pablo
Zhang, Tianwei
Saha, Anindya
Li, Shanghuo
Goldsmith, Paul F.
Bronfman, Leonardo
Lee, Chang Won
Taniguchi, Kotomi
Das, Swagat Ranjan
Gorai, Prasanta
Hoque, Ariful
Chen, Li
Kou, Zhiping
Zhou, Jianjun
Zhang, Yankun
Toth, L. Viktor
Baug, Tapas
Shen, Xianjin
Li, Chuanshou
Zou, Jiahang
Das, Ankan
Nazeer, Hafiz
Dewangan, L. K.
Hwang, Jihye
Chibueze, James O.
Astrophysics of Galaxies
The Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures (QUARKS) survey observed 139 infrared-bright (IR-bright) massive protoclusters at 1.3 mm wavelength with ALMA. This study investigates clump-to-core fragmentation and searches for candidate high-mass starless cores within IR-bright clumps using combined ALMA 12-m (C-2) and Atacama Compact Array (ACA) 7-m data, providing $\sim$ 1 arcsec ($\sim\rm0.02~pc$ at 3.7 kpc) resolution and $\sim\rm0.6\,mJy\,beam^{-1}$ continuum sensitivity ($\sim 0.3~M_{\odot}$ at 30 K). We identified 1562 compact cores from 1.3 mm continuum emission using getsf. Observed linear core separations ($λ_{\rm obs}$) are significantly less than the thermal Jeans length ($λ_{\rm J}$), with the $λ_{\rm obs}/λ_{\rm J}$ ratios peaking at $\sim0.2$. This indicates that thermal Jeans fragmentation has taken place within the IR-bright protocluster clumps studied here. The observed low ratio of $λ_{\rm obs}/λ_{\rm J}\ll 1$ could be the result of evolving core separation or hierarchical fragmentation. Based on associated signatures of star formation (e.g., outflows and ionized gas), we classified cores into three categories: 127 starless, 971 warm, and 464 evolved cores. Two starless cores have mass exceeding 16$\,M_{\odot}$, and represent high-mass candidates. The scarcity of such candidates suggests that competitive accretion-type models could be more applicable than turbulent core accretion-type models in high-mass star formation within these IR-bright protocluster clumps.
title The ALMA-QUARKS Survey: III. Clump-to-core fragmentation and search for high-mass starless cores
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2508.03229