Barry Rice

- doing science on a terrestrial planet -

Astronomy research (return)

My research at Steward Observatory focused on star formation in the Milky Way, and especially in the young (about five million years old) galactic cluster NGC 2264. This star formation region is filled with young stars, dust, and gas.

A major advancement in understanding this cluster was made by surveying the point sources in this region. This survey was combined with work by C.J. Lada, Erick Young, and Tom Greene, to produce a catalogue of 4900 detections at the V, R, I, J, H, and K photometric bands. I built a device that could be used with existing infrared imaging camera hardware. This device enabled high quality polarimetric maps to be made of sources such as Sharpless 106, Sharpless 140, and also a region in NGC 2264.

Using the coordinates obtained by making the multiband survey mentioned above, the spectra of 361 sources in NGC 2264 were obtained. I wanted to determine the spectral types of these stars, but since the spectra spanned the range 3690-6960 Angstroms, I had to extend the MK classification system to these red wavelengths. Using spectra published in the literature, temperature and luminosity sensitive features were identified and this extension was accomplished.

The hydrogen and calcium spectral lines of the stars in NGC 2264 were often in emission, as expected for young stars such as T Tauri stars.

Stars with absorption lines that are narrower than expected were defined as anemic stars. It was seen that this classification which was based purely on spectral characters also carried over to photometric characteristics.

Furthermore, I found the dereddened SEDs could be modelled as cases of stars surrounded by disks with holes. These simple disk models were very successful.


10 November 2007