BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:On the baryon-driven contraction of dark matter halos DTSTART;VALUE=DATE-TIME:20230324T084000Z DTEND;VALUE=DATE-TIME:20230324T085500Z DTSTAMP;VALUE=DATE-TIME:20241114T092453Z UID:indico-contribution-213@meetings.aip.de DESCRIPTION:Speakers: Pengfei Li (Leibniz-Institute for Astrophysics at Po tsdam)\nThe gravitational interaction between dark matter (DM) and baryons has long been ignored when building galaxies semi-empirically and observa tionally. In this talk\, I will show that the baryonic gravity leads to an adiabatic contraction of DM halos\, ignoring which would result in the bu ilt galaxies that are not in a dynamic equilibrium and hence cannot exist in reality. We propose a new approach to fitting galaxy rotation curves by numerically calculating the contraction of DM halos. We find adiabatic co ntraction makes DM halos more cuspy for massive galaxies\, so that their r otation curves cannot be fit without systematically reducing baryonic cont ributions. We also examine the baryonic effect on the predicted radial acc eleration relation of cold DM model\, and find the predicted relations of massive galaxies are systematically higher than observed. Both tensions po int to a core-cusp problem\, a classical problem for dwarf galaxies but pe rsisting in massive galaxies as well due to strong adiabatic contraction. In order to reconcile this problem\, feedback must work in massive galaxie s as efficiently as in dwarf galaxies.\n\nhttps://iaus379.aip.de/event/20/ contributions/213/ LOCATION:Haus H\, Telegrafenberg URL:https://iaus379.aip.de/event/20/contributions/213/ END:VEVENT END:VCALENDAR