May 16 – 18, 2025
College of Management, National Formosa University 國立虎尾科技大學第三校區文理暨管理大樓
Asia/Taipei timezone
The ASROC2025 Program is Now Available!

Unveiling Hidden Lyman-Alpha Emitters in DESI with Deep Learning

May 16, 2025, 5:00 PM
15m
International Conference Hall 圓形國際會議廳 (College of Management, National Formosa University 國立虎尾科技大學第三校區文理暨管理大樓)

International Conference Hall 圓形國際會議廳

College of Management, National Formosa University 國立虎尾科技大學第三校區文理暨管理大樓

632 雲林縣虎尾鎮民主路63號文理暨管理大樓 第三校區圓形國際會議廳(文理暨管理大樓一樓) National Formosa University, 1F College of Managment, Huwei Township, Yunlin County, Taiwan

Speaker

Mr Jui-Kuan Chan (National Taiwan University)

Description

Millions of spectra have been collected by the Dark Energy Spectroscopic Instrument (DESI) survey. While the DESI survey is designed to observe specific types of sources, unexpected sources are often included and hidden within the dataset. In this talk, I will show that a fraction of the sources observed by DESI are galaxies producing strong Lyman-alpha emission lines, known as Lyman-alpha emitters (LAEs), at redshifts greater than 2. These LAEs remain hidden in the DESI dataset because the survey and its data pipeline are not designed to detect them. To identify LAEs within the DESI dataset, we have developed and trained a convolutional neural network algorithm capable of automatically detecting LAEs, determining their redshifts, and estimating the emission line profiles simultaneously. Applying this algorithm to a million DESI spectra, we successfully identify approximately 15,000 LAEs. Finally, I will discuss the applications of this newly identified LAE sample, including its role in preparing for the DESI-II survey, which will select LAEs as one of its main target populations, as well as its use in investigating the physical properties of LAEs through high-quality combined spectra.

Section Galaxy/Extragalactic

Primary authors

Mr Jui-Kuan Chan (National Taiwan University) Dr Ting-Wen Lan (National Taiwan University)

Presentation materials

There are no materials yet.