THE FIRST Hi-GAL OBSERVATIONS OF THE OUTER GALAXY: A LOOK AT STAR FORMATION IN THE THIRD GALACTIC QUADRANT IN THE LONGITUDE RANGE 216. Degree-Sign 5 {approx}< l {approx}< 225. Degree-Sign 5

Journal Article · Sat Jul 20 00:00:00 EDT 2013 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/772/1/45· OSTI ID:22121848

Elia, D.; Molinari, S.; Schisano, E.; Pestalozzi, M.; Benedettini, M.; Di Giorgio, A. M.; Pezzuto, S.; Rygl, K. L. J. ^[1]; Fukui, Y.; Hayakawa, T.; Yamamoto, H. ^[2]; Olmi, L. ^[3]; Veneziani, M. ^[4]; Schneider, N.; Piazzo, L. ^[5]; Ikhenaode, D. ^[6]; Mizuno, A. ^[7]; Onishi, T. ^[8]; Polychroni, D. ^[9]

---

1. Istituto di Astrofisica e Planetologia Spaziali-INAF, Via Fosso del Cavaliere 100, I-00133 Roma (Italy)
2. Department of Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan)
3. Osservatorio Astrofisico di Arcetri-INAF, Largo E. Fermi 5, I-50125 Firenze (Italy)
4. Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States)
5. IRFU/SAp CEA/DSM, Laboratoire AIM CNRS, Universit Paris Diderot, F-91191 Gif-sur-Yvette (France)
6. DIET-Dipartimento di Ingegneria dell'Informazione, Elettronica e Telecomunicazioni, Universita di Roma La Sapienza, via Eudossina 18, I-00184 Roma (Italy)
7. Solar-Terrestrial Environment Laboratory, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan)
8. Department of Physical Science, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan)
9. Department of Astrophysics, Astronomy and Mechanics, Faculty of Physics, University of Athens, Panepistimiopolis, 15784 Zografos, Athens (Greece)

We present the first Herschel PACS and SPIRE photometric observations in a portion of the outer Galaxy (216. Degree-Sign 5 {approx}< l {approx}< 225. Degree-Sign 5 and -2 Degree-Sign {approx}< b {approx}< 0 Degree-Sign ) as a part of the Hi-GAL survey. The maps between 70 and 500 {mu}m, the derived column density and temperature maps, and the compact source catalog are presented. NANTEN CO(1-0) line observations are used to derive cloud kinematics and distances so that we can estimate distance-dependent physical parameters of the compact sources (cores and clumps) having a reliable spectral energy distribution that we separate into 255 proto-stellar and 688 starless sources. Both typologies are found in association with all the distance components observed in the field, up to {approx}5.8 kpc, testifying to the presence of star formation beyond the Perseus arm at these longitudes. Selecting the starless gravitationally bound sources, we identify 590 pre-stellar candidates. Several sources of both proto- and pre-stellar nature are found to exceed the minimum requirement for being compatible with massive star formation based on the mass-radius relation. For the pre-stellar sources belonging to the Local arm (d {approx}< 1.5 kpc) we study the mass function whose high-mass end shows a power law N(log M){proportional_to}M {sup -1.0{+-}0.2}. Finally, we use a luminosity versus mass diagram to infer the evolutionary status of the sources, finding that most of the proto-stellar sources are in the early accretion phase (with some cases compatible with a Class I stage), while for pre-stellar sources, in general, accretion has not yet started.

• OSTI ID: 22121848
• Journal Information: Astrophysical Journal, Vol. 772, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
CATALOGS
DENSITY
DISTANCE
ENERGY SPECTRA
GALAXIES
LUMINOSITY
MASS
PHOTOMETRY
STARS
TEMPERATURE DISTRIBUTION