3D MC. II. X-Ray Echoes Reveal a Clumpy Molecular Cloud in the CMZ
X-ray observations collected over the past decades have revealed a strongly variable X-ray signal within the Milky Way’s Galactic center, interpreted as X-ray echoes from its supermassive black hole, Sgr A*. These echoes are traced by the strong Fe K α fluorescent line at 6.4 keV, the intensity of w...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2025-01-01
|
| Series: | The Astronomical Journal |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/1538-3881/adbaf3 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849390112227459072 |
|---|---|
| author | Danya Alboslani Cara Battersby Samantha W. Brunker Maïca Clavel Dani Lipman Daniel L. Walker |
| author_facet | Danya Alboslani Cara Battersby Samantha W. Brunker Maïca Clavel Dani Lipman Daniel L. Walker |
| author_sort | Danya Alboslani |
| collection | DOAJ |
| description | X-ray observations collected over the past decades have revealed a strongly variable X-ray signal within the Milky Way’s Galactic center, interpreted as X-ray echoes from its supermassive black hole, Sgr A*. These echoes are traced by the strong Fe K α fluorescent line at 6.4 keV, the intensity of which is proportional to the density of the illuminated molecular gas. Over time, the echo scans through molecular clouds (MCs) in our Galactic center, revealing their 3D structure and highlighting their densest parts. While previous studies have utilized spectral line Doppler shifts along with kinematic models to constrain the geometry of the Central Molecular Zone (CMZ) or to study the structure of individual clouds, these methods have limitations, particularly in the turbulent region of the CMZ. We use archival Chandra X-ray data to construct one of the first 3D representations of one prominent MC, the Stone cloud, located at ( ℓ = 0 $\mathop{.}\limits^{\unicode{x000b0}}$ 068, b = –0 $\mathop{.}\limits^{\unicode{x000b0}}$ 076) at a distance of ∼20 pc from Sgr A* in projection. Using the Chandra X-ray Observatory, we followed the X-ray echo in this cloud from 2008 to 2017. We combine these data with 1.3 mm dust continuum emission observed with the Submillimeter Array (SMA) and the Herschel Space Observatory to reconstruct the 3D structure of the cloud and estimate the column densities for each year’s observed slice. The analysis of the X-ray echoes, along with velocities from SMA molecular line data, indicates that the structure of the Stone cloud can be described as a very diffuse background with multiple dense clumps throughout. |
| format | Article |
| id | doaj-art-b4cc9de425794dd48db63ad1decd4edb |
| institution | Kabale University |
| issn | 1538-3881 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astronomical Journal |
| spelling | doaj-art-b4cc9de425794dd48db63ad1decd4edb2025-08-20T03:41:46ZengIOP PublishingThe Astronomical Journal1538-38812025-01-01169421310.3847/1538-3881/adbaf33D MC. II. X-Ray Echoes Reveal a Clumpy Molecular Cloud in the CMZDanya Alboslani0https://orcid.org/0009-0005-9578-2192Cara Battersby1https://orcid.org/0000-0002-6073-9320Samantha W. Brunker2https://orcid.org/0000-0001-6776-2550Maïca Clavel3https://orcid.org/0000-0003-0724-2742Dani Lipman4https://orcid.org/0000-0002-5776-9473Daniel L. Walker5https://orcid.org/0000-0001-7330-8856University of Connecticut , Department of Physics, 196A Auditorium Road, Unit 3046, Storrs, CT 06269, USAUniversity of Connecticut , Department of Physics, 196A Auditorium Road, Unit 3046, Storrs, CT 06269, USAUniversity of Connecticut , Department of Physics, 196A Auditorium Road, Unit 3046, Storrs, CT 06269, USAUniv. Grenoble Alpes , CNRS, IPAG, F-38000 Grenoble, FranceUniversity of Connecticut , Department of Physics, 196A Auditorium Road, Unit 3046, Storrs, CT 06269, USAUniversity of Connecticut , Department of Physics, 196A Auditorium Road, Unit 3046, Storrs, CT 06269, USA; ALMA Regional Centre Node, Jodrell Bank Centre for Astrophysics, The University of Manchester , Manchester M13 9PL, UKX-ray observations collected over the past decades have revealed a strongly variable X-ray signal within the Milky Way’s Galactic center, interpreted as X-ray echoes from its supermassive black hole, Sgr A*. These echoes are traced by the strong Fe K α fluorescent line at 6.4 keV, the intensity of which is proportional to the density of the illuminated molecular gas. Over time, the echo scans through molecular clouds (MCs) in our Galactic center, revealing their 3D structure and highlighting their densest parts. While previous studies have utilized spectral line Doppler shifts along with kinematic models to constrain the geometry of the Central Molecular Zone (CMZ) or to study the structure of individual clouds, these methods have limitations, particularly in the turbulent region of the CMZ. We use archival Chandra X-ray data to construct one of the first 3D representations of one prominent MC, the Stone cloud, located at ( ℓ = 0 $\mathop{.}\limits^{\unicode{x000b0}}$ 068, b = –0 $\mathop{.}\limits^{\unicode{x000b0}}$ 076) at a distance of ∼20 pc from Sgr A* in projection. Using the Chandra X-ray Observatory, we followed the X-ray echo in this cloud from 2008 to 2017. We combine these data with 1.3 mm dust continuum emission observed with the Submillimeter Array (SMA) and the Herschel Space Observatory to reconstruct the 3D structure of the cloud and estimate the column densities for each year’s observed slice. The analysis of the X-ray echoes, along with velocities from SMA molecular line data, indicates that the structure of the Stone cloud can be described as a very diffuse background with multiple dense clumps throughout.https://doi.org/10.3847/1538-3881/adbaf3Molecular cloudsGalactic centerX-ray astronomy |
| spellingShingle | Danya Alboslani Cara Battersby Samantha W. Brunker Maïca Clavel Dani Lipman Daniel L. Walker 3D MC. II. X-Ray Echoes Reveal a Clumpy Molecular Cloud in the CMZ The Astronomical Journal Molecular clouds Galactic center X-ray astronomy |
| title | 3D MC. II. X-Ray Echoes Reveal a Clumpy Molecular Cloud in the CMZ |
| title_full | 3D MC. II. X-Ray Echoes Reveal a Clumpy Molecular Cloud in the CMZ |
| title_fullStr | 3D MC. II. X-Ray Echoes Reveal a Clumpy Molecular Cloud in the CMZ |
| title_full_unstemmed | 3D MC. II. X-Ray Echoes Reveal a Clumpy Molecular Cloud in the CMZ |
| title_short | 3D MC. II. X-Ray Echoes Reveal a Clumpy Molecular Cloud in the CMZ |
| title_sort | 3d mc ii x ray echoes reveal a clumpy molecular cloud in the cmz |
| topic | Molecular clouds Galactic center X-ray astronomy |
| url | https://doi.org/10.3847/1538-3881/adbaf3 |
| work_keys_str_mv | AT danyaalboslani 3dmciixrayechoesrevealaclumpymolecularcloudinthecmz AT carabattersby 3dmciixrayechoesrevealaclumpymolecularcloudinthecmz AT samanthawbrunker 3dmciixrayechoesrevealaclumpymolecularcloudinthecmz AT maicaclavel 3dmciixrayechoesrevealaclumpymolecularcloudinthecmz AT danilipman 3dmciixrayechoesrevealaclumpymolecularcloudinthecmz AT daniellwalker 3dmciixrayechoesrevealaclumpymolecularcloudinthecmz |