Unveiling the Nature of Type Ia Supernovae with Early-phase Photometry by Subaru/HSC

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K23456
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0204:Astronomy, earth and planetary science, and related fields
• Research Institution: The University of Tokyo
• Principal Investigator: Jiang Jian 東京大学, カブリ数物連携宇宙研究機構, 特任研究員 (00846503)
• Project Period (FY): 2019-08-30 – 2022-03-31
• Keywords: Supernova / Observation / Survey / Transient / Time-domain

Outline of Final Research Achievements

Our team carried out a series of observations with the 8.2m Subaru telescope from 2019 to 2021. Over 10 early-phase Type Ia supernovae (SNe Ia) have been discovered by Subaru/HSC and follow-up observations have been conducted for most of them by using various telescopes through domestic and international collaborations. On the other hand, another early-phase SN Ia that shows interesting features has been found by the Tomo-e Gozen transient survey. These early-phase SNe Ia helped us to further understand the explosion mechanism and progenitor system of specific SN Ia subclasses. In addition, a fast-evolving ultra-luminous transient, MUSSES2020J, has been discovered by our Subaru observation in 2020, which provides a unique opportunity of studying these rare and extreme astronomical phenomena in the universe. Three scientific papers based on the Subaru/HSC observations have already been published/accepted.

Free Research Field

Astronomy

Academic Significance and Societal Importance of the Research Achievements

Ia型超新星は宇宙膨張測定に用いられてきているが、その起源はよくわかっていない。早期観測によって起源解明への重要な情報をえることができ、将来より高精度な宇宙膨張測定が可能になることが期待される。