Gravitational lensing reveals cool gas within 10-20 kpc around a quiescent galaxy

• DOI: 10.1038/s42005-024-01778-4
• Publication Date: 2024-08-24T05:02:17Z
• Authors: Tania M. Barone; Glenn G. Kacprzak; James W. Nightingale; Nikole M. Nielsen; Karl Glazebrook; Kim-Vy H. Tran; Tucker Jones; Hasti Nateghi; Keerthi Vasan Gop...; Nandini Sahu; Themiya Nanayakkara; Hannah Skobe; Jesse van de Sande; Sebastian Lopez; Geraint F. Lewis
• Keywords: Strong gravitational lensing

While quiescent galaxies have comparable amounts of cool gas in their outer circumgalactic medium (CGM) compared to star-forming galaxies, they significantly less interstellar gas. However, open questions remain on the processes causing stop forming stars and stay quiescent. Theories suggest dynamical interactions with hot corona prevent from reaching galaxy, therefore predicting inner regions galaxy CGMs are devoid there is a lack understanding due spatial information quasar-sightline methods. We present integral-field spectroscopy probing 10–20 kpc (2.4–4.8 Re) around massive using gravitationally lensed galaxy. detect absorption Magnesium (MgII) implying large atomic (108.4–109.3 M⊙ T~104 Kelvin), galaxies. Lens modeling Hubble imaging also reveals diffuse asymmetric component significant mass consistent extent MgII absorption, offset light profile. This study demonstrates power galaxy-scale gravitational lenses not only probe but independently CGM it's effect. Quiescent similar amount star yet why remains an question. The authors investigate passive background faint, use lensing configuration constrain total geometry this reservoir.