3-D CMZ II: Hierarchical Structure Analysis of the Central Molecular Zone

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Battersby, Cara, Walker, Daniel L., Barnes, Ashley, Ginsburg, Adam, Lipman, Dani, Alboslani, Danya, Hatchfield, H Perry, Bally, John, Glover, Simon C. O., Henshaw, Jonathan D., Immer, Katharina, Klessen, Ralf S., Longmore, Steven N., Mills, Elisabeth A. C., Molinari, Sergio, Smith, Rowan, Sormani, Mattia C., Tress, Robin G., Zhang, Qizhou
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915043611770880
author Battersby, Cara
Walker, Daniel L.
Barnes, Ashley
Ginsburg, Adam
Lipman, Dani
Alboslani, Danya
Hatchfield, H Perry
Bally, John
Glover, Simon C. O.
Henshaw, Jonathan D.
Immer, Katharina
Klessen, Ralf S.
Longmore, Steven N.
Mills, Elisabeth A. C.
Molinari, Sergio
Smith, Rowan
Sormani, Mattia C.
Tress, Robin G.
Zhang, Qizhou
author_facet Battersby, Cara
Walker, Daniel L.
Barnes, Ashley
Ginsburg, Adam
Lipman, Dani
Alboslani, Danya
Hatchfield, H Perry
Bally, John
Glover, Simon C. O.
Henshaw, Jonathan D.
Immer, Katharina
Klessen, Ralf S.
Longmore, Steven N.
Mills, Elisabeth A. C.
Molinari, Sergio
Smith, Rowan
Sormani, Mattia C.
Tress, Robin G.
Zhang, Qizhou
contents The Central Molecular Zone (CMZ) is the way station at the heart of our Milky Way Galaxy, connecting gas flowing in from Galactic scales with the central nucleus. Key open questions remain about its 3-D structure, star formation properties, and role in regulating this gas inflow. In this work, we identify a hierarchy of discrete structures in the CMZ using column density maps from Paper I (Battersby et al., submitted). We calculate the physical ($N$(H$_2$), $T_{\rm{dust}}$, mass, radius) and kinematic (HNCO, HCN, and HC$_3$N moments) properties of each structure as well as their bolometric luminosities and star formation rates (SFRs). We compare these properties with regions in the Milky Way disk and external galaxies. Despite the fact that the CMZ overall is well below the Gao-Solomon dense gas star-formation relation (and in modest agreement with the Schmidt-Kennicutt relation), individual structures on the scale of molecular clouds generally follow these star-formation relations and agree well with other Milky Way and extragalactic regions. We find that individual CMZ structures require a large external pressure ($P_e$/k$_B$ $> 10^{7-9}$ K cm$^{-3}$) to be considered bound, however simple estimates suggest that most CMZ molecular-cloud-sized structures are consistent with being in pressure-bounded virial equilibriuim. We perform power-law fits to the column density probability distribution functions (N-PDFs) of the inner 100 pc, SgrB2, and the outer 100 pc of the CMZ as well as several individual molecular cloud structures and find generally steeper power-law slopes ($-9<α<-2$) compared with the literature ($-6 < α< -1$).
format Preprint
id arxiv_https___arxiv_org_abs_2410_17332
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle 3-D CMZ II: Hierarchical Structure Analysis of the Central Molecular Zone
Battersby, Cara
Walker, Daniel L.
Barnes, Ashley
Ginsburg, Adam
Lipman, Dani
Alboslani, Danya
Hatchfield, H Perry
Bally, John
Glover, Simon C. O.
Henshaw, Jonathan D.
Immer, Katharina
Klessen, Ralf S.
Longmore, Steven N.
Mills, Elisabeth A. C.
Molinari, Sergio
Smith, Rowan
Sormani, Mattia C.
Tress, Robin G.
Zhang, Qizhou
Astrophysics of Galaxies
Solar and Stellar Astrophysics
The Central Molecular Zone (CMZ) is the way station at the heart of our Milky Way Galaxy, connecting gas flowing in from Galactic scales with the central nucleus. Key open questions remain about its 3-D structure, star formation properties, and role in regulating this gas inflow. In this work, we identify a hierarchy of discrete structures in the CMZ using column density maps from Paper I (Battersby et al., submitted). We calculate the physical ($N$(H$_2$), $T_{\rm{dust}}$, mass, radius) and kinematic (HNCO, HCN, and HC$_3$N moments) properties of each structure as well as their bolometric luminosities and star formation rates (SFRs). We compare these properties with regions in the Milky Way disk and external galaxies. Despite the fact that the CMZ overall is well below the Gao-Solomon dense gas star-formation relation (and in modest agreement with the Schmidt-Kennicutt relation), individual structures on the scale of molecular clouds generally follow these star-formation relations and agree well with other Milky Way and extragalactic regions. We find that individual CMZ structures require a large external pressure ($P_e$/k$_B$ $> 10^{7-9}$ K cm$^{-3}$) to be considered bound, however simple estimates suggest that most CMZ molecular-cloud-sized structures are consistent with being in pressure-bounded virial equilibriuim. We perform power-law fits to the column density probability distribution functions (N-PDFs) of the inner 100 pc, SgrB2, and the outer 100 pc of the CMZ as well as several individual molecular cloud structures and find generally steeper power-law slopes ($-9<α<-2$) compared with the literature ($-6 < α< -1$).
title 3-D CMZ II: Hierarchical Structure Analysis of the Central Molecular Zone
topic Astrophysics of Galaxies
Solar and Stellar Astrophysics
url https://arxiv.org/abs/2410.17332