UNVEILING A NETWORK OF PARALLEL FILAMENTS IN THE INFRARED DARK CLOUD G14.225-0.506

Journal Article · Wed Feb 20 04:00:00 EST 2013 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/764/2/L26· OSTI ID:22130888

Busquet, Gemma ^[1]; Zhang, Qizhou; Ho, Paul T. P. ^[2]; Palau, Aina; Girart, Josep M. ^[3]; Liu, Hauyu Baobab ^[4]; Sanchez-Monge, Alvaro ^[5]; Estalella, Robert ^[6]; De Gregorio-Monsalvo, Itziar ^[7]; Pillai, Thushara ^[8]; Wyrowski, Friedrich ^[9]; Santos, Fabio P.; Franco, Gabriel A. P., ^[10]

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1. INAF-Istituto di Astrofisica e Planetologia Spaziali, via Fosso del Cavaliere 100, I-00133 Roma (Italy)
2. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
3. Institut de Ciencies de l'Espai (CSIC-IEEC), Campus UAB, Facultat de Ciencies, Torre C-5 parell, E-08193 Bellaterra, Catalunya (Spain)
4. Academia Sinica Institute of Astronomy and Astrophysics, Taipei, Taiwan (China)
5. INAF, Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-05125 Firenze (Italy)
6. Departament d'Astronomia i Meteorologia, Institut de Ciencies del Cosmos (ICC), Universitat de Barcelona (IEEC-UB), Marti i Franques 1, E-08028 Barcelona, Catalunya (Spain)
7. European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748 Garching (Germany)
8. Caltech Astronomy Department, MC 249-17, 1200 East California Boulevard, Pasadena, CA 91125 (United States)
9. Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany)
10. Departamento de Fisica-ICEx-UFMG, Caixa Postal 702, 30.123-970 Belo Horizonte-MG (Brazil)

We present the results of combined NH{sub 3} (1,1) and (2,2) line emission observed with the Very Large Array and the Effelsberg 100 m telescope of the infrared dark cloud G14.225-0.506. The NH{sub 3} emission reveals a network of filaments constituting two hub-filament systems. Hubs are associated with gas of rotational temperature T{sub rot} {approx} 15 K, non-thermal velocity dispersion {sigma}{sub NT} {approx} 1 km s{sup -1}, and exhibit signs of star formation, while filaments appear to be more quiescent (T{sub rot} {approx} 11 K and {sigma}{sub NT} {approx} 0.6 km s{sup -1}). Filaments are parallel in projection and distributed mainly along two directions, at P.A. {approx} 10 Degree-Sign and 60 Degree-Sign , and appear to be coherent in velocity. The averaged projected separation between adjacent filaments is between 0.5 pc and 1 pc, and the mean width of filaments is 0.12 pc. Cores within filaments are separated by {approx}0.33 {+-} 0.09 pc, which is consistent with the predicted fragmentation of an isothermal gas cylinder due to the {sup s}ausage{sup -}type instability. The network of parallel filaments observed in G14.225-0.506 is consistent with the gravitational instability of a thin gas layer threaded by magnetic fields. Overall, our data suggest that magnetic fields might play an important role in the alignment of filaments, and polarization measurements in the entire cloud would lend further support to this scenario.

• OSTI ID: 22130888
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 2 Vol. 764; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
AMMONIA
CLOUDS
DISPERSIONS
EMISSION
FILAMENTS
FRAGMENTATION
GAS CYLINDERS
GRAVITATIONAL INSTABILITY
LAYERS
MAGNETIC FIELDS
POLARIZATION
STARS
TELESCOPES