Distance to three molecular clouds in the central molecular zone

Autor: Mathias Schultheis, Francisco Nogueras-Lara, Nadine Neumayer, Rainer Schödel
Přispěvatelé: German Research Foundation, Ministerio de Ciencia, Innovación y Universidades (España), European Commission
Rok vydání: 2021
Předmět:
Zdroj: Digital.CSIC: Repositorio Institucional del CSIC
Consejo Superior de Investigaciones Científicas (CSIC)
Digital.CSIC. Repositorio Institucional del CSIC
instname
DOI: 10.13039/501100000780
Popis: This is an open access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Open Access funding provided by Max Planck Society.
Context. The determination of absolute and relative distances of molecular clouds along the line-of-sight towards the central molecular zone (CMZ) is crucial for inferring its orbital structure and dynamics and for understanding star formation in the clouds. Aims. Recent work has suggested that the G0.253+0.016 cloud (the Brick) does not belong to the CMZ. This motivated us to crosscheck those results, computing the absolute and relative distances to the Brick as well as to another two molecular clouds (the 50 km s-1 and the 20 km s-1 clouds), and discuss their CMZ membership. Methods. We used the colour magnitude diagrams Ks versus H-Ks to compare stars detected towards the target clouds with stars detected towards three reference regions in the nuclear stellar disc (NSD) and the Galactic bulge. We used red clump (RC) stars to estimate the distance to each region. Results. We found that all the clouds present a double RC feature. Such a double RC has been reported in previous work for the NSD, but not for the bulge adjacent to it. We exclude the possibility that the different RC features are located at significantly different distances. The obtained absolute and relative distances are compatible with the Galactic centre distance (∼8 kpc). © 2021 F. Nogueras-Lara et al.
This work is based on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 195.B-0283. We thank the staff of ESO for their great efforts and helpfulness. We thank Steven Longmore for useful discussion and comments on the manuscript. F.N.-L. and N.N. gratefully acknowledge support by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) - Project-ID 138713538 - SFB 881 ("The Milky Way System", subproject B8). R.S. acknowledges financial support from the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award for the Instituto de Astrofisica de Andalucia (SEV-2017-0709). R.S. acknowledges financial support from national project PGC2018-095049-B-C21 (MCIU/AEI/FEDER, UE).
Databáze: OpenAIRE
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