jeremy King - US grants

ABSTRACT

King, Jeremy
"NStars: Spectroscopic Abundances in Nearby Solar-Type Stars"
AST-0086576

Dr. King is measuring photospheric chemical abundances for 5000 solar-type stars within 60 parsecs of the Sun using low-resolution spectroscopy. Additional high resolution spectroscopy is performed for a subset of these stars to examine the frequency of chromospheric activity, multiplicity, kinematics, rotation rates, ages, and metallicities with which to address issues concerning planetary companions, circumstellar environment, and the Galactic chemical evolution history. The project also seeks to address how these parameters vary among stars in nearby open clusters. The necessary observations are performed at NSF-supported Cerro Tololo Inter-American Observatory, and the Lick, Keck and McDonald Observatories. The large quantity of information on stars in the solar neighborhood that is collected in the course of this project is incorporated into the NStars database, where it is widely available to the astronomical community.
Funding for this project was provided by the NSF Stellar Astronomy & Astrophysics (AST/SAA) program through the joint NSF/NASA "Nearby Stars (NStars)" initiative, and the NSF Mathematical & Physical Sciences Directorate Office of Multidisciplinary Activities (MPS/OMA).

Proposal ID: AST-0239518
Institution: Clemson University
PI: King, Jeremy

Dr. Jeremy King will use his CAREER award at Clemson University to determine high precision chemical abundances for the stars in a sample of open clusters. He will consistently determine the abundances of Li, C, O, Na, Mg, Al, Si, K, Ca, Ti, Cr, Fe, and Ni; these elements have varied nucleosynthetic origins, circumstellar condensation temperatures, and contributions to interior/atmospheric stellar opacities. Dr. King will use the magnitude and variations of these derived abundances to address several fundamental astrophysical issues, including the efficacy of standard stellar models, the relationship between age and metallicity in the galactic disk, the relationship between age and chromospheric emission in stars, and the absolute ages of star clusters. He will also study the chemical homogeneity in several kinematically-defined "stellar moving groups" as a test of their existence.

In addition to his research, Dr. King will enable the growth of observational astronomy at Clemson University through education and outreach. He will involve undergraduate students in his research, and develop astronomy-related Java applets containing self-assessment and conceptual extension exercises. The development of a dedicated astronomy server, Tiger Premier Astronomy Web Server (TigerPAWS), will not only meet the increased needs of the undergraduate students but also provide educational materials for K-12 classrooms. He will also deliver astronomy outreach programs to several different groups in South Carolina: TigerTailgate Astronomy at football games, Tigers Towards Astronomy In the Life of Seniors (TigerTAILS) for senior citizens, Tiger Rural Observational Astronomy Resource (TigerROAR) for rural K-12 students populating special education classrooms, and Tiger STudents Routinely In Precarious Educational Settings (TigerSTRIPES), aimed at youth under the care of the juvenile detention system.

AST-0908342
King

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).

Dr. Jeremy King and his students will utilize high-resolution spectroscopy to address several longstanding or timely issues of fundamental stellar astrophysics. Firstly, they will identify short-period tidally-locked binaries in globular clusters to provide an improved estimate of the big-bang production of lithium and thereby obtain a direct estimate of lithium destruction in the old stars of the Milky Way's halo. Secondly, the group will participate in an already-initiated program to investigate the large dispersion of lithium abundances in the cool stars of the Pleiades cluster, the source of which is not currently understood. Thirdly, they will initiate a program to identify exoplanets using spectrographs on meter-class telescopes to detect chromospheric flux variations due to star-planet interactions. Fourthly, they will search for and study the properties of nearby post-T-Tauri stars, which are stars like the Sun but with ages corresponding to the epoch of terrestrial planet formation. Finally, the PI and his students will derive spectroscopic parameters and abundances of stars of varying evolutionary states in an old disk moving group to establish whether this kinematic entity exhibits chemical homogeneity.

Dr. King will actively involve physics majors and summer students at South Carolina State University in all aspects of the program. This collaboration will build partnerships between research-class universities and institutions like SCSU that are successful in graduating minority students in astrophysics. The PI will continue providing undergraduate research and publication opportunities for Clemson University students. The fundamental nature of the research is expected to have a broad impact on the field of stellar astrophysics and the programs of other researchers in this field.