Haffner 16: A Young Moving Group in the Making

Abstract

The photometric properties of main sequence (MS) and pre-main sequence (PMS) stars in the young cluster Haffner 16 are examined using images recorded with the Gemini South Adaptive Optics Imager (GSAOI) and corrected for atmospheric blurring by the Gemini Multi-Conjugate Adapative Optics System (GeMS). A rich population of PMS stars is identified, and comparisons with isochrones suggest an age < 10 Myr assuming a distance modulus of 13.5 (D = 5 kpc). When compared with the solar neighborhood, Haffner 16 is roughly a factor of two deficient in objects with sub-solar masses. PMS objects in the cluster are also more uniformly distributed on the sky than bright MS stars. It is suggested that Haffner 16 is dynamically evolved, and that it is shedding protostars with sub-solar masses. Young low mass clusters like Haffner 16 are one possible source of PMS stars in the field. The cluster will probably evolve on time scales of ~ 100 - 1000 Myr into a diffuse moving group with a mass function that is very different from that which prevailed early in its life.

To appear in the Publications of the Astronomical Society of the Pacific

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Cited by in corpus (5)

• Gemini multi-conjugate adaptive optics system review I: Design, trade-offs and integration
• GeMS in the Outer Galaxy: Near-Infrared Imaging of Three Young Clusters at Large Galactic Radii
• The Distribution of Main Sequence and Pre-Main Sequence Stars in the Young Anticenter Cluster NGC 2401
• Galactic astronomy with AO: Nearby star clusters and moving groups
• Haffner 16 Redux: Revisiting a Young Cluster in the Outer Galaxy