Rapid Rotation of Low-mass Red Giants Using Apokasc: a Measure of Interaction Rates on the Post-main-sequence
Year: 2015
Type: article
Abstract: We investigate the occurrence rate of rapidly rotating ( >10 km s −1 ), low-mass giant stars in the Apache Point Observatory Galaxy Evolution Experiment- Kepler (APOKASC) fields with asteroseismic mass and surface gravity measurements. Such stars are likely merger products and their frequency places interesting constraints on stellar population models. We also identify anomalous rotators, i.e., stars with 5 km s −1 < < 10 km s −1 that are rotating significantly faster than both angular momentum evolution predictions and the measured rates of similar stars. Our data set contains fewer rapid rotators than one would expect given measurements of the Galactic field star population, which likely indicates that asteroseismic detections are less common in rapidly rotating red giants. The number of low-mass moderate (5–10 km s −1 ) rotators in our sample gives a lower limit of 7% for the rate at which low-mass stars interact on the upper red giant branch because single stars in this mass range are expected to rotate slowly. Finally, we classify the likely origin of the rapid or anomalous rotation where possible. KIC 10293335 is identified as a merger product and KIC 6501237 is a possible binary system of two oscillating red giants.
Source: The Astrophysical Journal
Authors: Jamie Tayar, Tugdual Ceillier, D. A. García-Hernández, Nicholas W. Troup, Savita Mathur, Rafael A. García, O. Zamora, Jennifer A. Johnson, Marc H. Pinsonneault, Szabolcs Mészáros, Carlos Allende Prieto, William J. Chaplin, Yvonne Elsworth, Saskia Hekker, David L. Nidever, David Salabert, Donald P. Schneider, Aldo Serenelli, Matthew Shetrone, Dennis Stello
Institutions: The Ohio State University, Centre National de la Recherche Scientifique, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Astrophysique, Instrumentation et Modélisation, Institut de Recherche sur les Lois Fondamentales de l'Univers, Universidad de La Laguna, Instituto de Astrofísica de Canarias, University of Virginia, Space Science Institute, Eötvös Loránd University, Aarhus University, University of Birmingham, Max Planck Institute for Solar System Research, University of Michigan, Pennsylvania State University, Institute of Space Sciences, Consejo Superior de Investigaciones Científicas, McDonald Observatory, The University of Sydney
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
Awards: Stellar Rotation and the Chronology of the Galaxy, Collaborative Research: Ages for Red Giants, New Insights into the Star Formation History of the Milky Way, SAP PURCHASE REQUISITION: 4200416562 - WHILE THE KEPLER MISSION'S MAIN GOAL CONSISTS OF SEARCHING FOR EXOPLANETS THROUGH THE DETECTION OF TRANSITS, A, Asteroseismology and Helioseismology at Birmingham and Queen Mary, G8885709231
OpenAlex ID: W2168595868