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Upcoming Seminar/Colloqium

Topic:

Exploring the physical scenario of the stripped envelope and the interacting supernovae

Speaker : Anjasha Gangopadhyay
Affiliation : ARIES
Date & Time :
Venue : Auditorium
Abstract :

Supernovae (SNe) are the giant stellar explosions that radiates a huge amount of energy 10$^{51-52}$ erg outshining the entire galaxy endorsing chemical enrichment. Observational classification diversifies SNe into Hydrogen rich and Hydrogen poor sub-class. However, peculiarities exist for which some SNe may gain outer envelopes due to interaction with circumstellar medium (CSM) while some may shred outer envelopes due to high stellar winds/accretion. In this talk, I will briefly mention about the typical characteristics of the representative members of the stripped envelope SNe (SE-SNe) of type IIb, Ib and Ic (SNe 2015as, 2015ap and 2016P) and the interacting SNe of type IIn, Ibn (SNe 2012ab and 2019uo). The SE-SNe group represents a wide diversity in luminosities and a highly asymmetric ejecta configuration. I will discuss the proposed future work to establish whether these groups are distinct or they are linked by a continuum of outer layer. For the interacting SNe, heterogeneity in the light curves are inferred. We have detected flash ionisation signatures in SN 2019uo which is the second in the row after SN 2010al. Probing the H$\alpha$ profile of SN 2012ab, we inferred the possible scenario governing the interaction. To diversify the scenarios, I will also discuss a case study of ASASSN-14il whose H$\alpha$ profile indicates a different interaction geometry. In the recent past, some SE-SNe have shown interaction signatures when monitored over a timescale of several years. Long term spectroscopic monitoring of the SE-SNe group using the 4 m class telescopes of ARIES is quintessential to see their geometry and whether they interact on a longer timescale. Moreover, a systematic study of the LBV and WR stars is required to discern the progenitor scenario of type IIn and Ibn SNe. We aim to fulfil the above goals with the use of ARIES telescopes and other national/international observing facilities.

About Speaker :

Anjasha submitted her thesis. This talk is a part of the application process of her post-thesis-submission fellowship.