{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/hcn-j-4-3-hnc-j-1-0-mathrm-h-13-cn-j-1-0-and-1","title":"HCN $J$=4-3, HNC $J$=1-0, $\\mathrm{H^{13}CN}$ $J$=1-0, and $\\mathrm{HC_3N}$ $J$=10-9 Maps of Galactic Center Region I: Spatially-Resolved Measurements of Physical Conditions and Chemical Composition","arxiv_id":"1804.00666","date":"2018-04-02","proceeding":null,"authors":["Kunihiko Tanaka","Makoto Nagai","Kazuhisa Kamegai","Takahiro Iino.","Takeshi Sakai"],"abstract":"This {\\it supplement} paper presents the maps of HCN $J$=4-3, HNC $J$=1-0, $\\mathrm{H^{13}CN}$ $J$=1-0, and HC$_3$N $J$=10-9 for the Galactic central molecular zone (CMZ), which have been obtained using the Atacama Submillimeter Telescope Experiment and Nobeyama Radio Observatory 45-m telescope. Three-dimensional maps (2-D in space and 1-D in velocity) of the gas kinetic temperature ($T_\\mathrm{kin}$), hydrogen volume density ($n_\\mathrm{H_2}$), and fractional abundances of eight molecules (HCN, HNC, $\\mathrm{HC_3N}$, HCO$^+$, $\\mathrm{H_2CO}$, SiO, CS, and $\\mathrm{N_2H^+}$) have been constructed from our and archival data. We have developed a method with hierarchical Bayesian inference for this analysis, which has successfully suppressed the artificial correlations among the parameters created by systematic errors due to the deficiency in the simple one-zone excitation analysis and the calibration uncertainty. The typical values of $T_\\mathrm{kin}$ and $n_\\mathrm{H_2}$ are $10^{1.8}\\ $K and $10^{4.2}\\ \\mathrm{cm}^{-3}$, respectively, and the presence of an additional cold/low-density component is also indicated. The distribution of high-temperature regions is poorly correlated with known active star-forming regions, while a few of them coincide with shocked clouds. Principal component analysis has identified two distinct groups in the eight analyzed molecules: one group with large PC1 and PC2 scores and the other with a large $T_\\mathrm{kin}$ dependence, which could be explained using two regimes of shock chemistry with fast ($\\gtrsim 20\\ \\mathrm{km\\,s}^{-1}$) and slow ($\\lesssim 20\\ \\mathrm{km\\,s}^{-1}$) velocity shocks, respectively. This supports the idea that the mechanical sputtering of dust grains and the mechanical heating play primary roles in the chemical and thermal processes in CMZ clouds.","url_abs":"https://arxiv.org/abs/1804.00666v1","url_pdf":"https://arxiv.org/pdf/1804.00666v1.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"hcn-j-4-3-hnc-j-1-0-mathrm-h-13-cn-j-1-0-and-1","repo_url":"https://github.com/centralmolecularzone/datasets","is_official":0,"mentioned_in_paper":0,"mentioned_in_github":1,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"syntology_url":null,"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}