| Name: | Govind Nandakumar |
| Affiliation: | Department of astronomy and theoretical physics, Lund University |
| Conference ID : | ASI2023_68 |
| Title : | The Galactic chemical evolution of phosphorus observed with IGRINS |
| Authors : | Govind Nandakumar
Nils Ryde
Martin Montelius
Brian Thorsbro
Henrik Jonsson
Gregory Mace |
| Mode of Presentation: | Poster |
| Abstract Category : | Stars, ISM and Galaxy |
| Abstract : | Phosphorus (P) is considered to be one of the key elements for life, making it an important element to look for in the abundance analysis of spectra of stars. Yet, there exists only a handful of spectroscopic studies to estimate the P abundances and investigate its trend across a range of metallicities. This is due to the lack of good P lines in the optical wavelength region and the requirement of careful manual analysis of the blended P lines in near infrared H band spectra.
We determined P abundances for 37 K giants stars by fitting CO blended phosphorus line at 16482.92 Å in their IGRINS HK band spectra. We have reliable stellar parameters estimated using optical FIES spectra obtained in a previous study of the same set of stars called Giants in the Local Disk (GILD).
I will present [P/Fe] vs [Fe/H] trend for these stars in the metallicity range of -1.2 dex < [Fe/H] < 0.4 dex and compare this trend with the very limited literature sample as well as the theoretical chemical evolution trend in Cescutti et al. (2012). I will then discuss the possible nucleosynthetic origin sites of P by comparing it with other elemental abundances whose nucleosynthetic origins are comparatively well known. I will also discuss briefly about the two metal poor P enhanced s-rich stars belonging to the Milky Way halo population whose origins are a mystery. Finally I will discuss the best stars (i.e, the range of stellar parameters) to reliably measure P abundance from the P I line at 16482.92 Å. |
