Public Seminar of MPhil Candidate:- Excitation of multi-phase emission nebulae in giant elliptical galaxies
The giant elliptical galaxies at the centers of galaxy clusters can host luminous emission-line nebulae that span up to tens of kpc, which in some cases are closely associated with recent star formation. The manner by which these nebulae form and are energized, and consequently their physical properties and propensity for star formation, are poorly understood. In his thesis, the speaker presents spectroscopy of atomic and molecular emission lines from the nebula in NGC5044, the BCG of the NGC5044 group. He demonstrates, for the first time, strong kinematic coupling between the atomic(H-alpha) and molecular(H2, CO) phases of the nebula, suggesting emission from common gas volumes. This is consistent with excitation by penetration of energetic particles from the surrounding hot X-ray intracluster medium into the nebula. The speaker also shows that the relative strengths of the high- and low-ionization lines from the nebula are consistent with excitation by energetic particles.
時間：2021.12.20(一) 15:30
地點：香港大學 莊月明物理樓518室；或
頻道：Zoom ID:997-6284-6838←318060
講者：James Michael George NIANIAS(香港大學)
語言：英語
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【此屬轉載訊息，以主事單位發佈為準】
此活動由香港大學物理系.主辦。
