Detection of Small-Amplitude Oscillations in the G-Giant HD76294 (ζ Hydrae)

Publications of the Astronomical Society of Japan

Kambe, Eiji⁴  Sato, Bun’ei¹  Ando, Hiroyasu²  Tan, Kefeng³  Zhao, Gang³ 

[1] Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550;National Astronomical Observatory of Japan, National Institutes of Natural Sciences, 2-21-1 Osawa, Mitaka, Tokyo 181-8588Department of Astronomy, Graduate University for Advanced Studies, Shonan Village, Hayama, Kanagawa 240-0193Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033;National Astronomical Observatories, Chinese Academy of Sciences, A20 Datun Road, Chaoyang District, Beijing 100012, China ,;Okayama Astrophysical Observatory, National Astronomical Observatory of Japan, National Institutes of Natural Sciences, 3037-5 Honjo, Kamogata, Asakuchi, Okayama 719-0232

关键词: asteroseismology;    "stars: G giants";    "stars: individual (ζ Hydrae)";    "stars: oscillations";    "stars: statistics";    "techniques: radial velocities";   

DOI  :  10.1093/pasj/60.2.219

学科分类：天文学(综合)

来源: Oxford University Press

【 摘 要 】

Wemadeapreciseradial-velocitymeasurementoftheG-giant$$zeta$$Hyawithaniodinecelltechnique,andfoundsmall-amplitudeoscillations.Thetimescaleoftheoscillationswas6–10hours,inwhichawavymotionwasclearlyseen.Theirpowerspectrumshowsamaximumpeakfrequencyof38.3$$mu$$Hz.Afurtherperiodanalysiswithapre-whiteningprocedurerevealsthatthefourpeaks,including38.3$$mu$$Hz,aresignificant.Thepeakfrequencyofthepowerenvelopeoftheoscillationsisabout35$$mu$$Hz,whichisquitelowcomparedwithavalue(about60$$mu$$Hz)predictedbythescalinglaw.Wealsopointoutthatthepowerexcessisconfinedtoaverynarrowbandwidth(40$$mu$$Hz)comparedwithpreviouslyobservedGgiants,$$xi$$Hyaand$$epsilon$$Oph.

【 授权许可】

Unknown