First Results From The Hertzsprung Song Telescope: Asteroseismology Of The G5 Subgiant Star {\Mu}Her

Autor: Grundahl, F., Andersen, M. Fredslund, Christensen-Dalsgaard, J., Antoci, V., Kjeldsen, H., Handberg, R., Houdek, G., Bedding, T. R., Pallé, P. L., Jessen-Hansen, J., Aguirre, V. Silva, White, T. R., Frandsen, S., Albrecht, S., Andersen, M. I., Arentoft, T., Brogaard, K., Chaplin, W. J., Harpsøe, K., Jørgensen, U. G., Karovicova, I., Karoff, C., Rasmussen, P. Kjærgaard, Lund, M. N., Lundkvist, M. Sloth, Skottfelt, J., Sørensen, A. Norup, Tronsgaard, R., Weiss, E.
Rok vydání: 2017
Předmět:
Druh dokumentu: Working Paper
DOI: 10.3847/1538-4357/836/1/142
Popis: We report the first asteroseismic results obtained with the Hertzsprung SONG Telescope from an extensive high-precision radial-velocity observing campaign of the subgiant muHerculis. The data set was collected during 215 nights in 2014 and 2015. We detected a total of 49 oscillation modes with l values from 0 to 3, including some l = 1 mixed modes. Based on the rotational splitting observed in l = 1 modes, we determine a rotational period of 52 days and a stellar inclination angle of 63 degrees. The parameters obtained through modeling of the observed oscillation frequencies agree very well with independent observations and imply a stellar mass between 1.11 and 1.15M_sun and an age of 7.8+/-0.4 Gyr. Furthermore, the high-quality data allowed us to determine the acoustic depths of the He II ionization layer and the base of the convection zone.
Comment: 17 pages, 15 figures. Accepted for publication in ApJ
Databáze: arXiv