BEGIN:VCALENDAR VERSION:2.0 CALSCALE:GREGORIAN PRODID:iCalendar-Ruby BEGIN:VEVENT CATEGORIES:Lectures & Presentations DESCRIPTION:Physics Colloquium | The Galaxy-Halo Connection from Gravitatio nal LensingAstronomy\, April 2\n\nThe Physics & Astronomy Colloquium Series presents Alexie Leauthaud of University of California\, Santa Cruz on “The Galaxy-Halo Connection from Gravitational Lensing” on Friday\, April 2\, a t 4:10 p.m. at an Online Departmental Colloquium.\n\nJoin on your computer or mobile app \n\nClick here to join the meeting \n\nOr call in (audio only ) \n\n+1 614-706-6572\,\,519079818# United States\, Columbus \n\nPhone Co nference ID: 519 079 818# \n\nAbstract: I will begin this talk with an over view of galaxy-galaxy lensing and how it informs us about the connection be tween galaxies and their dark matter halos. I will then present a variety o f new results in this field. First\, I will discuss the “lensing is low” ef fect whereby the lensing signal around massive galaxies has a lower amplitu de than predicted based on the galaxy auto-correlation function from BOSS. I will present some new updates on this topic and discuss the cosmological implications of this effect. I will further present “Lensing without Border s”\, an inter survey collaborative effort to empirically test the accuracy of galaxy-galaxy lensing measurements in current day surveys. I will also p resent new results suggesting that the light from central galaxies is a muc h better tracer of halo mass than previously recognized and I will discuss how this effect might be used to improve optical cluster finding algorithms . Finally\, I will present the Merian survey: a new program that will use 60 nights on the Blanco telescope and two custom made filters to detect 100 \,000 dwarf galaxies and measure their halo masses via gravitational lensin g. DTEND:20210402T211000Z DTSTAMP:20241123T085459Z DTSTART:20210402T201000Z LOCATION: SEQUENCE:0 SUMMARY:Physics Colloquium | The Galaxy-Halo Connection from Gravitational Lensing\, April 2 UID:tag:localist.com\,2008:EventInstance_35714779802367 URL:https://calendar.ohio.edu/event/physics_colloquium_astronomy_april_2 END:VEVENT END:VCALENDAR