Theoretical modelling of light curves and spectra for supernovae
Lead Research Organisation:
Queen's University Belfast
Department Name: Sch of Mathematics and Physics
Abstract
The PhD project will focus on performing radiative transfer simulations to compute synthetic spectra and light curves from explosion models and comparing these to real observational data.
The student will learn the physical principles and computational algorithms used in Monte Carlo radiative transfer calculations and will become experienced in running and analysing the results of simulations. The project will focus on a combination of improving the quality of the simulations (improving and testing of microphysics) and modelling of observations. This work be carried out in the context of international collaborations with theorists (particularly those specialising in thermonuclear supernova explosions) and supernova observers (at Queens University Belfast, and internationally).
The student will learn the physical principles and computational algorithms used in Monte Carlo radiative transfer calculations and will become experienced in running and analysing the results of simulations. The project will focus on a combination of improving the quality of the simulations (improving and testing of microphysics) and modelling of observations. This work be carried out in the context of international collaborations with theorists (particularly those specialising in thermonuclear supernova explosions) and supernova observers (at Queens University Belfast, and internationally).
Organisations
People |
ORCID iD |
| Stuart Sim (Primary Supervisor) | |
| Fionntan Callan (Student) |
Publications
Blondin S
(2022)
StaNdaRT: a repository of standardised test models and outputs for supernova radiative transfer
in Astronomy & Astrophysics
Lach F
(2022)
Type Iax supernovae from deflagrations in Chandrasekhar mass white dwarfs
in Astronomy & Astrophysics
Lach F
(2022)
Models of pulsationally assisted gravitationally confined detonations with different ignition conditions
in Astronomy & Astrophysics
Magee M
(2022)
An analysis of the spectroscopic signatures of layering in the ejecta of Type Iax supernovae
in Monthly Notices of the Royal Astronomical Society
Maunder T
(2024)
Synthetic light curves and spectra from a self-consistent 2D simulation of an ultra-strippped supernova
in Monthly Notices of the Royal Astronomical Society
Pakmor R
(2022)
On the fate of the secondary white dwarf in double-degenerate double-detonation Type Ia supernovae
in Monthly Notices of the Royal Astronomical Society
Srivastav S
(2023)
The Luminous Type Ia Supernova 2022ilv and Its Early Excess Emission
in The Astrophysical Journal Letters
Srivastav S
(2022)
SN 2020kyg and the rates of faint Iax supernovae from ATLAS
in Monthly Notices of the Royal Astronomical Society
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| ST/T506369/1 | 30/09/2019 | 29/09/2023 | |||
| 2302542 | Studentship | ST/T506369/1 | 30/09/2019 | 30/03/2023 | Fionntan Callan |
| Description | Supernovae are extremely bright astrophysical events associated with the explosive deaths of stars. They are so luminous that individual supernovae can be observed in distant galaxies and monitored as they rise and fade over weeks to years. Aside from being spectacular events in their own right, they are vital for multiple branches of modern astrophysics research: they are the nuclear furnaces in which many of the familiar chemical elements are forged, can regulate star formation in galaxies, and are used as cosmological probes of the expansion of the Universe. Additionally, the study of supernovae encompasses a wide variety of fascinating topics including atomic physics, nuclear fusion and quantum mechanics. The work carried out during this award focused on Type Ia supernovae, which result from the thermonuclear explosions of white dwarf stars. Despite extensive study the explosion mechanisms that produce type Ia supernovae (SNe Ia) are still poorly understood. Modern telescope surveys have demonstrated SNe Ia to be a diverse class, consisting of multiple sub-classes, which likely result from different explosion scenarios. The largest and most diverse peculiar sub-class of SNe Ia are type Iax supernovae (SNe Iax). Previous studies have shown pure deflagrations of Chandrasekhar mass carbon oxygen white dwarfs (CO WDs) are the most promising scenario to explain SNe Iax. In this scenario a thermonuclear runaway is ignited near the centre of a Chandrasekhar mass CO WD with the thermonuclear burning front always propagating below the sound speed of the WD (as a deflagration). Previous simulations of deflagration models predict synthetic observables in reasonable agreement with observed SNe Iax but are unable to match the full diversity of the SNe Iax sub-class and show some systematic differences. This work primarily focused on time-dependent Monte Carlo radiative transfer simulations of Chandrasekhar mass CO WD pure deflagration models and their comparisons with SNe Iax to investigate if the differences can be resolved. We first presented 3D synthetic observables, calculated using an approximate NLTE treatment in our radiative transfer simulations (ARTIS-CLASSIC), for an extensive parameter study of single spark pure deflagration models. These models produce good agreement with bright and intermediate luminosity SNe Iax although some systematic differences persist. Additionally, such models struggle to reproduce the faintest events. We demonstrated that including the contribution from a luminous remnant, predicted by pure deflagration models and suggested to have been observed for SNe Iax, leads to improved agreement with observations. We also presented a simulation of a deflagration model up to 30 days after explosion using an improved NLTE treatment of the plasma in the radiative transfer (ARTIS-NLTE). This represents the first such simulation of a pure deflagration model. Significant NLTE effects are found in the synthetic light curves and spectra which lead to an overall improved agreement with observed SNe Iax. We finally investigated one alternative explosion scenario for Chandrasekhar mass CO WDs known as the Gravitationally Confined Detonation (GCD) scenario. In this scenario the deflagration is followed by a detonation. We presented 3D synthetic observables calculated using ARTIS-CLASSIC for a parameter study of the GCD scenario and compared with observed SNe Ia. We found that the GCD scenario remains most promising for the over-luminous 91T-like SNe Ia sub-class but does not provide a good match to any of the other SNe Ia sub-classes. Overall the work presented in this thesis strengthens the case of pure deflagration models as the explanation for SNe Iax however differences still remain. |
| Exploitation Route | Future work should focus on investigating the nature of the luminous remnant, predicted by pure deflagration models and suggested to have been observed for SNe Iax, in more detail as well as simulating the radiative transfer for both standard pure deflagration models and those with the remnant contribution included utilising a full NLTE treatment of the plasma conditions. |
| Sectors | Digital/Communication/Information Technologies (including Software) Other |
| URL | https://pure.qub.ac.uk/en/studentTheses/investigating-the-origins-of-thermonuclear-supernovae-through-mul |