An Infrared Census of Star Formation in the Horsehead Nebula
arXiv:0901.0564 · doi:10.1088/0004-6256/137/3/3685
Abstract
At ~ 400 pc, the Horsehead Nebula (B33) is the closest radiatively-sculpted pillar to the Sun, but the state and extent of star formation in this structure is not well understood. We present deep near-infrared (IRSF/SIRIUS JHKs) and mid-infrared (Spitzer/IRAC) observations of the Horsehead Nebula in order to characterize the star forming properties of this region and to assess the likelihood of triggered star formation. Infrared color-color and color-magnitude diagrams are used to identify young stars based on infrared excess emission and positions to the right of the Zero-Age Main Sequence, respectively. Of the 45 sources detected at both near- and mid-infrared wavelengths, three bona fide and five candidate young stars are identified in this 7' by 7' region. Two bona fide young stars have flat infrared SEDs and are located at the western irradiated tip of the pillar. The spatial coincidence of the protostars at the leading edge of this elephant trunk is consistent with the Radiation-Driven Implosion (RDI) model of triggered star formation. There is no evidence, however, for sequential star formation within the immediate ~ 1.5' (0.17 pc) region from the cloud/H II region interface.
30 pages, 11 figures; accepted for publication in The Astronomical Journal
References in corpus (18)
- Spitzer Observations of NGC 1333: A Study of Structure and Evolution in a Nearby Embedded Cluster
- A Combined Spitzer and Chandra Survey of Young Stellar Objects in the Serpens Cloud Core
- A Survey for New Members of Taurus with the Spitzer Space Telescope
- Absolute Physical Calibration in the Infrared
- X-ray Study of Triggered Star Formation and Protostars in IC 1396N
- iVINE - Ionization in the parallel tree/SPH code VINE: First results on the observed age-spread around O-stars
- Triggered star formation in Bright-Rimmed Clouds: The Eagle Nebula revisited
- Ionisation-induced star formation II: External irradiation of a turbulent molecular cloud
- A Census of the Carina Nebula -- II. Energy Budget and Global Properties of the Nebulosity
- Main-Seqence Fitting Distance to the sigma Ori Cluster
- An X-ray Census of Young Stars in the Massive Southern Star-Forming Complex NGC 6357
- Aromatic emission from the ionised mane of the Horsehead nebula
- Chandra Observations of the Eagle Nebula. I. Embedded Young Stellar Objects near the Pillars of Creation
- SCUBA observations of the Horsehead Nebula - what did the horse swallow?
- Sequential star formation in a cometary globule (BRC37) of IC1396
- Infrared Properties of Close Pairs of Galaxies
- Circumstellar discs in the young sigma Orionis cluster
- A radiation driven implosion model for the enhanced luminosity of protostars near HII regions