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arXiv · 2609.00135

ACES VII. Compact Continuum Source Catalog of the Central Molecular Zone

Abstract

The Central Molecular Zone (CMZ) resides in the inner few hundred parsecs of our Galaxy, and despite being the largest reservoir of dense molecular gas in the Milky Way, it has a relatively low present-day star formation rate (SFR) of $\sim0.08~M_{\odot}~\text{yr}^{-1}$. Continuum and spectral line observations from the Atacama Large Millimeter/submillimeter Array (ALMA) CMZ Exploration Survey (ACES) provide the first full-coverage, high-resolution map of the inner 200 parsecs of the CMZ at 3 mm. In this paper we present the ACES catalog of compact continuum sources, the most complete catalog of potential sites of star formation in the CMZ to date. Using an automated dendrogram-based source extraction procedure in combination with a by-eye morphological classification scheme, we produce a `full' catalog of 1735 detections in total. Additionally, we use spectral index measurements to generate a `filtered' catalog of 567 sources with minimal contamination from non-thermal filaments and extended free-free emission. We find that 359 ($\sim63\%$) of the filtered catalog sources are located at column densities $< 10^{23}$ cm$^{-2}$, outside of the densest molecular cloud regions, 195 of which have not been identified in previous surveys. After cross-referencing with various catalogs generated from data at different wavelengths, we consider it likely that many of these newly discovered detections are produced by pre/protostellar sources or compact HII regions.

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Jennifer Wallace, Cara Battersby, Nazar Budaiev, H Perry Hatchfield, Ashley T. Barnes, Taehwa Yoo, Miriam G. Santa-Maria, Antonio Daley, Q. Daniel Wang, Anika Schmiedeke, Kaitlyn E. Sheriff, Jairo Armijos-Abendaño, Daniel Walker, Gwenllian Williams, Dani R. Lipman, Farideh Mazoochi, Natalie O. Butterfield, Francisco Nogueras-Lara, Yoshiaki Sofue, Ralf S. Klessen, Simon C. O. Glover, Katharina Immer, Savannah R. Gramze, Katarzyna M. Dutkowska, Rojita Buddhacharya, Laura Colzi, Ashley Lieber, Alyssa Bulatek, Michael Wieber, Pablo García, Denise Riquelme-Vásquez, Emad Alkhuja, Yue Hu, Dennis Perlot, Howard A. Smith, Victor M. Rivilla, Wenyu Jiao, Fengwei Xu, Jonathan D. Henshaw, Adam Ginsburg, Elisabeth A. C. Mills, Qizhou Zhang, Steven N. Longmore, Nguyen M. Khang, Galaxy Salo, Jakub Poznanski, Dylan Pare, Maya Petkova, Izaskun Jiménez-Serra, Xing Lu, Sergio Martin, Alvaro Sanchez-Monge, Bijas Najimudeen, Christoph Federrath, Tabassum S. Tanvir, Pei-Ying Hsieh, John Bally, Paul Ho, Mattia C. Sormani, Robin G. Tress, Jaime E. Pineda. 2026-08-31. ACES VII. Compact Continuum Source Catalog of the Central Molecular Zone. https://arxiv.org/abs/2609.00135

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