We investigate the neutrino-process in an energetic Type Ic supernova (SN Ic) and resultant productions of the light elements including boron and its stable isotopes. SN Ic is a very unique boron source because it can produce boron through not only spallation reactions as discussed in Nakamura & Shigeyama (2004) but also the neutrino-process. The neutrino-process is considered to occur in core-collapse supernovae and previous studies were limited to Type II supernovae (SNe II). Although the progenitor star of an SN Ic does not posses a He envelope so that 7Li production via the neutrino-process is unlikely, 11B can be produced in the C-rich layers. We demonstrate a hydrodynamic simulation of SN Ic explosion and estimate the amounts of the light elements produced via the neutrino-process for the first time, and also the subsequent spallation reactions between the outermost layers of compact SN Ic progenitor and the ambient medium. We find that the neutrino-process in the current SN Ic model produces a significant amount of 11B, which is diluted by 10B from spallation reactions to get closer to B isotopic ratios observed in meteorites. We also confirm that high-temperature mu- and tau-neutrinos and their anti-neutrinos, reasonably suggested from the compact structure of SN Ic progenitors, enhance the light element production through the neutral-current reactions, which may imply an important role of SNe Ic in the Galactic chemical evolution.
We use the results of a supernova light-curve population synthesis to predict the range of possible supernova light curves arising from a population of single-star progenitors that lead to type IIP supernovae. We calculate multiple models varying the initial mass, explosion energy, nickel mass and nickel mixing and then compare these to type IIP supernovae with detailed light curve data and pre-explosion imaging progenitor constraints. Where a good fit is obtained to observations, we are able to achieve initial progenitor and nickel mass estimates from the supernova lightcurve that are compara…
Novae and supernovae play a key role in many fields of Astrophysics and Cosmology. Despite their importance, an accurate description of which objects explode and why and how they explode is still lacking. One of the main characteristics of such explosions is that they are the main suppliers of newly synthesized chemical elements in the Galaxy. Since some of these isotopes are radioactive, it is possible to use the corresponding gamma-rays as a diagnostic tool of the explosion thanks to their independence on the thermal state of the debris. The drawback is the poor sensitivity of detectors in t…
Despite the importance of Type Ia supernovae as standard candles for cosmology and to the chemical evolution of the Universe, we still have no consistent picture of the nature of these events. Much progress has been made in the hydrodynamical explosion modelling of supernovae Ia in the last few years and fully 3-D explosion models are now available. However those simulations are not directly comparable to observations: to constrain explosion models, radiative transfer calculations must be carried out. We present a new 3-D Monte Carlo radiative transfer code which allows forward modelling of th…
We present substantial extensions to the Monte Carlo radiative transfer code TARDIS to perform spectral synthesis for type II supernovae. By incorporating a non-LTE ionization and excitation treatment for hydrogen, a full account of free-free and bound-free processes, a self-consistent determination of the thermal state and by improving the handling of relativistic effects, the improved code version includes the necessary physics to perform spectral synthesis for type II supernovae to high precision as required for the reliable inference of supernova properties. We demonstrate the capabilities…
A Monte Carlo code (ARTIS) for modelling time-dependent three-dimensional spectral synthesis in chemically inhomogeneous models of Type Ia supernova ejecta is presented. Following the propagation of gamma-ray photons, emitted by the radioactive decay of the nucleosynthesis products, energy is deposited in the supernova ejecta and the radiative transfer problem is solved self-consistently, enforcing the constraint of energy conservation in the co-moving frame. Assuming a photoionisation dominated plasma, the equations of ionisation equilibrium are solved together with the thermal balance equati…
The spectrum of a supernova is a summation of numerous overlapping atomic line signatures. Consequently, empirical measurements are limited in application when compound features are assumed to be due to one or two spectral lines. Here I address matters of spectroscopic boundaries between normal and peculiar type I supernovae using multi-component empirical metrics. I discuss some obstacles faced when using supernova spectra to pair model with data and I demonstrate how spectrum synthesis can benefit from fairly complete observational coverage in wavelength and time.
The Demographics of Binary Companions to Stripped-Envelope Supernovae: Confronting Observations with Population Synthesis
Foundation for Research and Technology（研究与技术基金会）；Space Telescope Science Institute（太空望远镜科学研究所）；University of Toronto（多伦多大学）；Carnegie Institution for Science（卡内基科学促进会）；Northwestern University（西北大学）；Caltech/IPAC（加州理工学院/IPAC）；University of Washington（华盛顿大学）
We present results of a supernova light-curve population synthesis, predicting the range of possible supernova lightcurves arising from a population of progenitor stars that include interacting binary systems. We show that the known diversity of supernova lightcurves can be interpreted as arising from binary interactions. Given detailed models of the progenitor stars, we are able to the determine what parameters within these stars determine the shape of their supernova lightcurve. The primary factors are the mass of supernova ejecta and the mass of hydrogen in the final progenitor. We find tha…
(Abridged) The explosion mechanism of electron-capture supernovae (ECSNe) remains equivocal. We attempt to constrain the explosion mechanism (neutron-star-forming implosion or thermonuclear explosion) and the frequency of occurrence of ECSNe using nucleosynthesis simulations of the latter scenario, population synthesis, the solar abundance distribution, pre-solar meteoritic oxide grain isotopic ratio measurements and the white dwarf mass-radius relation. Tracer particles from 3d hydrodynamic simulations were post-processed with a large nuclear reaction network in order to determine the complet…
We infer the expected detection number of pair instability supernovae (PISNe) during the operation of the Euclid space telescope based on binary population models. Our models reproduce the global maximum of the rate at the primary BH mass of $\sim 9-10$ $M_\odot$, and the overall gradient of the primary BH mass distribution in the binary BH merger rate consistent with recent observations. We consider different PISN conditions depending on the $^{12}$C$(α, γ)^{16}$O reaction rate. The fiducial and $3σ$ models adopt the standard and $3σ$-smaller reaction rate, respectively. Our fiducial model pr…
Despite the significance of Type Ia supernovae (SNeIa) in many fields in astrophysics, SNeIa lack a theoretical explanation. The standard scenarios involve thermonuclear explosions of carbon/oxygen white dwarfs approaching the Chandrasekhar mass; either by accretion from a companion or by a merger of two white dwarfs. We investigate the contribution from both channels to the SNIa rate with the binary population synthesis (BPS) code SeBa in order to constrain binary processes such as the mass retention efficiency of WD accretion and common envelope evolution. We determine the theoretical rates …
The nature of the progenitors of Type Ia supernovae (SNe Ia) remains a mystery. Comparing theoretical rates and delay-time distributions of SNe Ia with those inferred observationally can constrain their progenitor models. In this work, taking thermohaline mixing into account in the helium-enriched main-sequence (HEMS) donor scenario, we address rates and delay times of SNe Ia in this channel by combining the results of self-consistent binary evolution calculations with population synthesis models. We find that the Galactic SN Ia rate from the HEMS donor scenario is around 0.6-1.2 per century, …
Neutron star-companion interaction in core collapse supernovae. Population synthesis based on detailed binary evolution models
Argelander Institut für Astronomie（阿根兰德天文研究所）；Max-Planck-Institut für Radioastronomie（马克斯·普朗克射电天文研究所）；Weizmann Institute of Science（魏茨曼科学研究所）；Max-Planck-Institut für Astrophysik（马克斯·普朗克天体物理研究所）；Institut d’Astrophysique de Paris, CNRS-Sorbonne Université（巴黎天体物理研究所，法国国家科学研究中心-索邦大学）；French-Chilean Laboratory for Astronomy, IRL 3386, CNRS（中法天文联合实验室，法国国家科学研究中心）；Pontificia Universidad Católica de Chile（智利天主教 Pontificia 大学）
Core-collapse supernovae (CCSNe) are the extremely energetic deaths of massive stars. They play a vital role in the synthesis and dissemination of many heavy elements in the universe. In the past, CCSN nucleosynthesis calculations have relied on artificial explosion methods that do not adequately capture the physics of the innermost layers of the star. The PUSH method, calibrated against SN1987A, utilizes the energy of heavy-flavor neutrinos emitted by the proto-neutron star (PNS) to trigger parametrized explosions. This makes it possible to follow the consistent evolution of the PNS and to en…
Physical Conditions for Synthesis of Sc, Ti, and V in Neutrino-driven Supernovae
Astronomical Science Program, Graduate Institute for Advanced Studies, SOKENDAI（日本国立天文台大学大学院高等研究院天文学专业）；National Astronomical Observatory of Japan, National Institutes of Natural Sciences（日本国立天文台，国立自然科学研究所）；Department of Physics, Faculty of Science and Engineering, Konan University（神户学院大学理工学部物理学科）；Yukawa Institute for Theoretical Physics, Kyoto University（京都大学汤川理论物理研究所）；Department of Astronomy, Graduate School of Science, The University of Tokyo（东京大学理学研究科天文学系）
The "Scenario Machine" (a computer code designed for studies of the evolution of close binaries) was used to carry out a population synthesis for a wide range of merging astrophysical objects: main-sequence stars with main-sequence stars; white dwarfs with white dwarfs, neutron stars, and black holes; neutron stars with neutron stars and black holes; and black holes with black holes.We calculate the rates of such events, and plot the mass distributions for merging white dwarfs and main-sequence stars. It is shown that Type Ia supernovae can be used as standard candles only after approximately …
Broad-lined type Ic supernovae (SNe Ic-BL) are of great importance because their association with long-duration gamma-ray bursts (LGRBs) holds the key to deciphering the central engine of LGRBs, which refrains from being unveiled despite decades of investigation. Among the two popularly hypothesized types of central engine, i.e., black holes and strongly magnetized neutron stars (magnetars), there is mounting evidence that the central engine of GRB-associated SNe (GRB-SNe) is rapidly rotating magnetars. Theoretical analysis also suggests that magnetars could be the central engine of SNe Ic-BL.…
The optical and optical/near-infrared pseudo-bolometric light curves of 85 stripped-envelope supernovae (SNe) are constructed using a consistent method and a standard cosmology. The light curves are analysed to derive temporal characteristics and peak luminosity $L_{\mathrm{p}}$, enabling the construction of a luminosity function. Subsequently, the mass of $^{56}$Ni synthesised in the explosion, along with the ratio of ejecta mass to ejecta kinetic energy, are found. Analysis shows that host-galaxy extinction is an important factor in accurately determining luminosity values as it is significa…
