Events
【DoA Seminar】July 8th by Jialu Li
Description
Title: Comprehensive High-Spectral-Resolution MIR Spectroscopy: Probing the Innermost Gas of Massive Protostars
Speaker：Jialu Li
Abstract:
The formation and evolution of massive stars are not well understood due to their deeply embedded nature. High-spectral-resolution mid-infrared (MIR) absorption spectroscopy offers a unique probe of warm, dense gas in the innermost regions of massive protostars, using the disk photosphere as a background continuum. This method resolves individual rovibrational transitions, avoids beam dilution, and provides precise constraints on physical conditions.
In this talk, I will present a comprehensive study of massive protostellar systems, based on high-resolution MIR observations (IRTF/iSHELL, SOFIA/EXES, Gemini/TEXES) targeting sources such as W3 IRS5 and NGC 7538 IRS1. I will discuss the molecular inventory revealed by hundreds of absorption lines and how our analysis constrains temperature, column density, and kinematics of the hot gas. I will also share recent results from NOEMA observations of vibrationally excited HCN, which provide complementary insight into the dense gas structures. Finally, I will highlight how our high-resolution SOFIA study aids the analysis of low-spectral-resolution JWST/MIRI data, where blending, optical depth effects, and partial coverage pose significant challenges.
Bio:
Jialu Li is a Postdoctoral Associate at the University of Maryland, College Park. Her research focuses on the formation of massive protostars during their deeply embedded hot core phases, combining high-spectral-resolution mid-infrared spectroscopy with submillimeter radio interferometry. She earned her B.S. in Astronomy from the University of Science and Technology of China and her Ph.D. in Astronomy from the University of Maryland.
Time: 14:00-15:00, 8/July, Tuesday
Venue: Room 506 (Large seminar room), Department of Astronomy
