WHAT IS CONTROLLING THE FRAGMENTATION IN THE INFRARED DARK CLOUD G14.225–0.506?: DIFFERENT LEVELS OF FRAGMENTATION IN TWIN HUBS
- Institut de Ciències de l’Espai (CSIC-IEEC), Campus UAB, Carrer de Can Magrans, S/N, E-08193, Cerdanyola del Vallès, Catalunya (Spain)
- Departament d’Astronomia i Meteorologia, Institut de Ciències del Cosmos (ICC), Universitat de Barcelona (IEEC-UB), Martí i Franquès, 1, E-08028 Barcelona, Catalunya (Spain)
- Instituto de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México, P.O. Box 3-72, 58090 Morelia, Michoacán, México (Mexico)
- Academia Sinica Institute of Astronomy and Astrophysics, Taipei, Taiwan (China)
- Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
- European Southern Observatory (ESO), Karl-Schwarzschild-Str. 2, D-85748 Garching (Germany)
- Max Planck Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn (Germany)
- Instituto de Astrofísica de Andalucía, CSIC, Glorieta de la Astronomía, s/n, E-18008, Granada (Spain)
We present observations of the 1.3 mm continuum emission toward hub-N and hub-S of the infrared dark cloud G14.225–0.506 carried out with the Submillimeter Array, together with observations of the dust emission at 870 and 350 μm obtained with APEX and CSO telescopes. The large-scale dust emission of both hubs consists of a single peaked clump elongated in the direction of the associated filament. At small scales, the SMA images reveal that both hubs fragment into several dust condensations. The fragmentation level was assessed under the same conditions and we found that hub-N presents 4 fragments while hub-S is more fragmented, with 13 fragments identified. We studied the density structure by means of a simultaneous fit of the radial intensity profile at 870 and 350 μm and the spectral energy distribution adopting a Plummer-like function to describe the density structure. The parameters inferred from the model are remarkably similar in both hubs, suggesting that density structure could not be responsible for determining the fragmentation level. We estimated several physical parameters, such as the level of turbulence and the magnetic field strength, and we found no significant differences between these hubs. The Jeans analysis indicates that the observed fragmentation is more consistent with thermal Jeans fragmentation compared with a scenario in which turbulent support is included. The lower fragmentation level observed in hub-N could be explained in terms of stronger UV radiation effects from a nearby H ii region, evolutionary effects, and/or stronger magnetic fields at small scales, a scenario that should be further investigated.
- OSTI ID:
- 22521395
- Journal Information:
- Astrophysical Journal, Vol. 819, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
Similar Records
UNVEILING A NETWORK OF PARALLEL FILAMENTS IN THE INFRARED DARK CLOUD G14.225-0.506
MAGNETICALLY DOMINATED PARALLEL INTERSTELLAR FILAMENTS IN THE INFRARED DARK CLOUD G14.225-0.506