{"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/galactic-synchrotron-emissivity-measurements","title":"Galactic synchrotron emissivity measurements between 250° < l < 355° from the GLEAM survey with the MWA","arxiv_id":"1611.05446","date":"2016-11-16","proceeding":null,"authors":["H. Su","N. Hurley-Walker","C. A. Jackson","N. M. McClure-Griffiths","S. J. Tingay","L. Hindson","P. Hancock","R. B. Wayth","B. M. Gaensler","L. Staveley-Smith","J. Morgan","M. Johnston-Hollitt","E. Lenc","M. E. Bell","J. R. Callingham","K. S. Dwarkanath","B. Q. For","A. D. Kapińska","B. McKinley","A. R. Offringa","P. Procopio","C. Wu","Q. Zheng"],"abstract":"Synchrotron emission pervades the Galactic plane at low radio frequencies, originating from cosmic ray electrons interacting with the Galactic magnetic field. Using a low-frequency radio telescope, the Murchison Widefield Array (MWA), we measure the free-free absorption of this Galactic synchrotron emission by intervening HII regions along the line of sight. These absorption measurements allow us to calculate the Galactic cosmic-ray electron emissivity behind and in front of 47 detected HII regions in the region $250^\\circ < l < 355^\\circ$, $|b| < 2^\\circ$. We find that all average emissivities between the HII regions and the Galactic edge along the line of sight ($\\epsilon_b$) are in the range of 0.24$\\,\\,\\sim\\,\\,$0.70$\\,\\,$K$\\,\\,$pc$^{-1}$ with a mean of 0.40$\\,\\,$K$\\,\\,$pc$^{-1}$ and a variance of 0.10$\\,\\,$K$\\,\\,$pc$^{-1}$ at 88$\\,\\,$MHz. Our best model, the Two-circle model, divides the Galactic disk into three regions using two circles centring on the Galactic centre. It shows a high emissivity region near the Galactic centre, a low emissivity region near the Galactic edge, and a medium emissivity region between these two regions, contrary to the trend found by previous studies.","url_abs":"http://arxiv.org/abs/1611.05446v2","url_pdf":"http://arxiv.org/pdf/1611.05446v2.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":"galactic-synchrotron-emissivity-measurements","repo_url":"https://github.com/HongquanSu/hongquansu.github.io","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}