Nov
04
2022

Stars that Freeze: White Dwarf Crystallization as Revealed by Gaia featuring Simon Blouin (University of Victoria) (Opens in a new window)

Online

Seminars

White dwarfs are stellar embers that simply cool down for the rest of time, eventually freezing into a solid state. This predictable evolution makes them precise cosmic clocks; they have been used for decades to measure the ages of stellar populations. But data from the Gaia space observatory is now calling into question the accuracy of this age dating technique. The cooling process appears to be much more delayed by the onset of crystallization than predicted by current models. I will present my recent work on the physics of core crystallization.

Oct
21
2022

Multidimensional Modelling of Magnetic Fields in Supernovae and Their Progenitors featuring Vishnu Varma (Keele, UK) (Opens in a new window)

Online

Seminars

Core-collapse supernovae (CCSNe) are some of the brightest, most energetic events in the universe. In order to model these phenomena accurately, we need to have a diverse range of physics such as neutrino transport and neutrino interactions, general-relativistic gravity, detailed equations of state (EoS) of dense matter, magnetohydrodynamic (MHD) and detailed progenitor models.

Oct
07
2022

The Contribution of Classical Novae to the Galactic Abundance of 26Al featuring Laetitia Canete (University of Surrey, UK) (Opens in a new window)

Online

Seminars

The discovery of radioactive 26Al via the observation of the 1809-keV γ ray in 1982 is one of the most famous pieces of evidence of on-going nucleosynthesis in the cosmos. The 26Al is likely to be produced dominantly in massive stars and supernovae. Nevertheless, a number of additional sources such as classical novae and AGB stars may still contribute considerably to the production of 26Al. Thus, up to 29% of the total observed 26Al abundance is predicted to have a nova origin. 

Feb
04
2022

IReNA Online Seminar featuring Daid Kahl, Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering (IFIN-HH) (Opens in a new window)

Online via Zoom

Seminars

Title: Radioactive Nuclides in Outer Space

Abstract: Nuclear astrophysics is generally the study of the energy generation in stars and the origins of the chemical elements. In this highly multidisciplinary field, the job of experimental nuclear physicists is to constrain the nuclear reaction rates which are linked with astronomical observables. Observation of the lightest chemical element with no stable isotopes, technetium, in stellar spectra, was the first evidence that nucleosynthesis is an on-going process in our Galaxy.

Apr
08
2021

Three-dimensional hydrodynamical simulations unravel the evolution of SN 1987A from the explosion to the supernova remnant (Opens in a new window)

IReNA Online Seminar

Seminars

Dr. Masaomi Ono

RIKEN

Abstract: Supernova 1987A (SN 1987A) provides a unique opportunity to unravel the  evolution of core-collapse supernovae (CCSNe) from the explosions to  their supernova remnants (SNRs) thanks to its proximity and youth. Early  observation of iron lines has indicated matter mixing during the  explosion to convey innermost 56Ni to outer layers. Since the density  structure of the progenitor star affects the matter mixing, it provides  a hint on the properties of the progenitor star.