{"id":498,"date":"2025-09-07T15:32:25","date_gmt":"2025-09-07T19:32:25","guid":{"rendered":"https:\/\/sites.bu.edu\/buwd\/?p=498"},"modified":"2025-09-07T16:07:09","modified_gmt":"2025-09-07T20:07:09","slug":"gravitational-redshift-bias-in-white-dwarf-spectra","status":"publish","type":"post","link":"https:\/\/sites.bu.edu\/buwd\/2025\/09\/07\/gravitational-redshift-bias-in-white-dwarf-spectra\/","title":{"rendered":"Gravitational redshift bias in white dwarf spectra"},"content":{"rendered":"<figure style=\"width: 646px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" src=\"\/buwd\/files\/2025\/09\/gravredshiftbias-636x228.jpg\" alt=\"\" width=\"636\" height=\"228\" class=\"aligncenter size-medium wp-image-499\" srcset=\"https:\/\/sites.bu.edu\/buwd\/files\/2025\/09\/gravredshiftbias-636x228.jpg 636w, https:\/\/sites.bu.edu\/buwd\/files\/2025\/09\/gravredshiftbias-768x276.jpg 768w, https:\/\/sites.bu.edu\/buwd\/files\/2025\/09\/gravredshiftbias.jpg 858w\" sizes=\"(max-width: 636px) 100vw, 636px\" \/><figcaption class=\"wp-caption-text\">Resolution-induced radial velocity for each white dwarf (the region in gray) showing the difference between its apparent radial velocity and expected gravitational redshift (from <a href=\"https:\/\/arxiv.org\/abs\/2508.04775\">Arseneau et al. 2025<\/a>).<\/figcaption><\/figure>\n<p>In August 2025, a manuscript led by graduate student and BUWD member Stefan Arseneau (<strong><a href=\"https:\/\/arxiv.org\/abs\/2508.04775\">Arseneau, Hermes, Zakamska et al. 2025<\/a><\/strong>) was accepted which showed that substantial biases (5-15 km\/s) exist in low-resolution radial velocity measurements, indicating that all the physics of line formation in high-density plasmas is not fully accounted for in state-of-the-art white dwarf model atmospheres. Using large samples from SDSS-V, we attempt to measure this bias and provide simple corrections for surveys like SDSS, DESI, and 4MOST. The manuscript has been accepted in <a href=\"https:\/\/arxiv.org\/abs\/2508.04775\">The Astrophysical Journal<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In August 2025, a manuscript led by graduate student and BUWD member Stefan Arseneau (Arseneau, Hermes, Zakamska et al. 2025) was accepted which showed that substantial biases (5-15 km\/s) exist in low-resolution radial velocity measurements, indicating that all the physics of line formation in high-density plasmas is not fully accounted for in state-of-the-art white dwarf [&hellip;]<\/p>\n","protected":false},"author":15801,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"_links":{"self":[{"href":"https:\/\/sites.bu.edu\/buwd\/wp-json\/wp\/v2\/posts\/498"}],"collection":[{"href":"https:\/\/sites.bu.edu\/buwd\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sites.bu.edu\/buwd\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sites.bu.edu\/buwd\/wp-json\/wp\/v2\/users\/15801"}],"replies":[{"embeddable":true,"href":"https:\/\/sites.bu.edu\/buwd\/wp-json\/wp\/v2\/comments?post=498"}],"version-history":[{"count":2,"href":"https:\/\/sites.bu.edu\/buwd\/wp-json\/wp\/v2\/posts\/498\/revisions"}],"predecessor-version":[{"id":504,"href":"https:\/\/sites.bu.edu\/buwd\/wp-json\/wp\/v2\/posts\/498\/revisions\/504"}],"wp:attachment":[{"href":"https:\/\/sites.bu.edu\/buwd\/wp-json\/wp\/v2\/media?parent=498"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sites.bu.edu\/buwd\/wp-json\/wp\/v2\/categories?post=498"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sites.bu.edu\/buwd\/wp-json\/wp\/v2\/tags?post=498"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}