NOAO >   Observing Info >   Approved Programs >   2016B-0108

Small NOAO Logo

Program Information for 2016B-0108


PI: Zachary Maas, Indiana U., zmaas@indiana.edu
Address: Department of Astronomy, 319 Swain West, Bloomington, IN, 47405 USA

CoI: Catherine A Pilachowski, Indiana U.

Title: Phosphorus Abundances in the Thin and Thick Disks

Abstract: We propose to measure phosphorus abundances from the P I features at 1.06 microns in thin and thick disk stars with -1.0<[Fe/H]<-0.4 using the Phoenix instrument on Gemini South. Chemical evolution models of phosphorus in the solar neighborhood are consistent with data for stars with metallicities below [Fe/H] <—1.5 but do not agree with stars at higher metallicities. Phosphorus abundances have been measured in few stars with -1.5<[Fe/H]<-0.4. Our sample will fill in a metallicity range where the [P/Fe] ratio transitions from greater than the model at [Fe/H]>-0.5 to consistent with models at [Fe/H]<-1.5 and help constrain chemical evolution models. Thin disk and thick disk models of phosphorus chemical evolution are offset by 0.1 dex in the metallicity range -1.0<[Fe/H]<-0.4. Additional abundance measurements in thin and thick stellar populations can also give insight to the formation of phosphorus.

Program Type: Standard/Galactic

Scheduled Nights:
Run 1 (2016B):  GEM-S-SVC/PHNX -- 21.5hrs band 3 (GS-2016B-Q-76)


National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360



NOAO >   Observing Info >   Approved Programs >   2016B-0108

noaoprop-help@noao.edu

Small NOAO Logo