Title:  Nova explosions and their influences on the origin of heavy elements and binary evolutions

Speaker: 钱声帮

Institute: 云南大学

Host: 顾为民

Time: 2025.2.27 周四 14:30

Location: 物理楼 552

Abstract:

Classical novae are caused by thermonuclear eruptions on the surfaces of white dwarfs accreting material from their hydrogen-rich companions in cataclysmic variables (CVs), which produces mass ejection and loss as well as influencing the evolutions of CVs. However, both the mass-loss rate and physical properties of CVs during nova outbursts are poorly understood. The release of a large amount of photometrically survey data provides a valuable opportunity to study the properties of classical novae. We have already carried out in-depth investigations on classical novae based on TESS data. In this talk, I will review some of the progresses. A large suddenly increase in the orbital period is discovered during a nova eruption, which is caused a mass ejection larger than 24 Jupiter masses. This is about two orders of magnitude larger than those determined ever before indicating that some classical novae may be major contributors to the origin of heavy elements. It also will cause a decline in accretion rate of the CV and thus a hibernation after the nova eruption. The precession and nutation of the accreting disk are found during the nova outburst. Meanwhile, the shortest-period novae are also detected and some binary systems may be merging during the nova eruptions. These results will shed light on the binary evolution, and suggest that classical novae, the most common astrophysical thermonuclear explosions, may be major contributors to Galactic-scale nucleosynthesis.

Bio:

钱声帮，云南大学物理与天文学院副院长，教授，博士生导师。国家“高层次人才特殊支持计划”领军人才，国家杰出青年基金获得者，国家创新人才推进计划中青年科技创新领军人才，云南省首批“云岭学者”和云南省劳模（先进工作者）。主要从事双星、系外行星和致密天体的研究。在国内外重要天文期刊上发表第一/通讯作者SCI论文120多篇，多次被授予英国物理学会（IOP）出版社“高被引作者奖”和连续4次入选爱思唯尔(Elsevier)“中国高被引学者”榜单。从2019年起，连续7次入选全球前2％顶尖科学家“终身科学影响力榜单”和“年度科学影响力榜单”。研究成果4次被评为全国十大天文科技进展，并获云南省科学技术奖励一等奖3次。主持国家自然科学基金重点、杰出青年基金等项目20多项。多次作为主席召开国际学术会议和国际天文培训学校，并多次做特邀报告。积极促进与“一带一路”国家间的科技合作与交流，建立了《云南省中泰天文联合研究中心》和《云南省面向南亚东南亚天文科技交流与教育培训基地》等国际科技合作基地。