{"id":922,"date":"2026-01-29T07:47:34","date_gmt":"2026-01-29T06:47:34","guid":{"rendered":"https:\/\/sites.lesia.obspm.fr\/the-good-vibrations-seminars\/?post_type=eap_event&#038;p=922"},"modified":"2026-05-15T15:13:16","modified_gmt":"2026-05-15T13:13:16","slug":"good-vibrations-seminar-s04e11-jeong-yun-choi-heidelberg-institute-for-theoretical-studies-germany","status":"publish","type":"eap_event","link":"https:\/\/sites.lesia.obspm.fr\/the-good-vibrations-seminars\/events\/good-vibrations-seminar-s04e11-jeong-yun-choi-heidelberg-institute-for-theoretical-studies-germany\/","title":{"rendered":"Good Vibrations Seminar S04E11: Jeong Yun Choi (Heidelberg Institute for Theoretical Studies, Germany)"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\"><strong>Behind the complex red-giant oscillation power spectra<\/strong><\/h2>\n\n\n\n<p><a href=\"https:\/\/sites.lesia.obspm.fr\/the-good-vibrations-seminars\/files\/2026\/01\/CV_Choi.pdf\">Jeong Yun Choi, HITS<\/a><\/p>\n\n\n\n<p>Solar-like oscillations in red giants show characteristic patterns of pressure modes and mixed modes that allow us to probe stellar interiors. However, some red giants exhibit power density spectra (PDS) with irregular mode patterns and unusually low oscillation power. Various physical processes can produce a wide range of complex PDS morphologies, including magnetic fields, structural discontinuities, rapid rotation, and strong coupling of mixed modes. In this talk, I present a new perspective in which some of these complex PDS originate from seismically unresolved oscillation signals, i.e., red-giant asteroseismic binaries (ABs).<\/p>\n\n\n\n<p>First, I present the predicted PDS morphologies of 5,000 artificial ABs to illustrate how seismically unresolved red-giant ABs are expected to appear in the observations. Next, I compare these predictions with six seismically unresolved AB candidates identified in <em>Kepler<\/em> data. With these six AB candidates, I will show how unresolved oscillations can bias stellar masses and radii by factors of up to ~ 3 and ~ 2, and make unreliable core properties such as period spacings and coupling factors. Finally, I will present a systematic search for red giants with complex PDS and investigate&nbsp;the origins of the complexity, including AB candidates and other physical processes.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Behind the complex red-giant oscillation power spectra Jeong Yun Choi, HITS Solar-like oscillations in red giants show characteristic patterns of<\/p>\n<p class=\"readmore\"><a href=\"https:\/\/sites.lesia.obspm.fr\/the-good-vibrations-seminars\/events\/good-vibrations-seminar-s04e11-jeong-yun-choi-heidelberg-institute-for-theoretical-studies-germany\/\" title=\"Read Good Vibrations Seminar S04E11: Jeong Yun Choi (Heidelberg Institute for Theoretical Studies, Germany)\">Read more &raquo;<\/a><\/p>\n","protected":false},"author":104,"featured_media":986,"comment_status":"open","ping_status":"closed","template":"","categories":[],"class_list":["post-922","eap_event","type-eap_event","status-publish","has-post-thumbnail","hentry"],"_links":{"self":[{"href":"https:\/\/sites.lesia.obspm.fr\/the-good-vibrations-seminars\/wp-json\/wp\/v2\/eap_event\/922","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sites.lesia.obspm.fr\/the-good-vibrations-seminars\/wp-json\/wp\/v2\/eap_event"}],"about":[{"href":"https:\/\/sites.lesia.obspm.fr\/the-good-vibrations-seminars\/wp-json\/wp\/v2\/types\/eap_event"}],"author":[{"embeddable":true,"href":"https:\/\/sites.lesia.obspm.fr\/the-good-vibrations-seminars\/wp-json\/wp\/v2\/users\/104"}],"replies":[{"embeddable":true,"href":"https:\/\/sites.lesia.obspm.fr\/the-good-vibrations-seminars\/wp-json\/wp\/v2\/comments?post=922"}],"version-history":[{"count":2,"href":"https:\/\/sites.lesia.obspm.fr\/the-good-vibrations-seminars\/wp-json\/wp\/v2\/eap_event\/922\/revisions"}],"predecessor-version":[{"id":987,"href":"https:\/\/sites.lesia.obspm.fr\/the-good-vibrations-seminars\/wp-json\/wp\/v2\/eap_event\/922\/revisions\/987"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/sites.lesia.obspm.fr\/the-good-vibrations-seminars\/wp-json\/wp\/v2\/media\/986"}],"wp:attachment":[{"href":"https:\/\/sites.lesia.obspm.fr\/the-good-vibrations-seminars\/wp-json\/wp\/v2\/media?parent=922"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sites.lesia.obspm.fr\/the-good-vibrations-seminars\/wp-json\/wp\/v2\/categories?post=922"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}