"""Model of the SED from type Ic-BL (broad-lined, stripped-envelope) supernovae."""
from typing import ClassVar
from astropy import units as u
from uvex_transients.models.arnett import ArnettDecaySED
from uvex_transients.models.core.parameters import Parameter
from uvex_transients.models.core.priors import (
ConstantPrior,
TruncatedNormalPrior,
UniformPrior,
)
__all__ = ["TypeIcBLSED"]
[docs]
class TypeIcBLSED(ArnettDecaySED):
r"""
Type Ic-BL (broad-lined) supernova SED, with priors fit to a ZTF sample of SNe Ic-BL.
Reuses :class:`~uvex_transients.models.arnett.ArnettDecaySED`'s radioactive-decay Arnett
diffusion and floored-photosphere blackbody entirely, exactly as
:class:`~uvex_transients.models.supernovae.Ia.TypeIaSED` does; only :attr:`_DEFAULT_PARAMETERS`
differs. The priors on ``M_Ni``, ``M_ej`` and ``v_ej`` are sample statistics (mean, sample
standard deviation) of the 36-event explosion-property table of :footcite:t:`srinivasaragavan2024`
(nickel mass, kinetic energy, ejecta mass and photospheric velocity per event). One event
(SN 2020wgz), whose reported
:math:`M_\mathrm{Ni}=2.46\,M_\odot` is a >5-sigma outlier driven by an ``e_k``/``m_ej`` *lower
limit* rather than a measurement, is excluded from the ``M_Ni`` statistics. ``M_ej`` uses only
rows with a measured (non-lower-limit) value, and ``v_ej`` is identified with the sample's
photospheric velocities (``v_ph``), regardless of the epoch quoted. ``kappa`` and ``T_floor``
are not constrained by that table and are left at `TypeIaSED`'s values; ``kappa_gamma`` is
instead fixed at a large value (full gamma-ray trapping across the simulated window), unlike
`TypeIaSED`'s Scalzo+14 value.
.. rubric:: Parameters
.. list-table::
:header-rows: 1
:widths: 18 18 64
* - Parameter
- Symbol
- Description
* - ``M_Ni``
- :math:`M_\mathrm{Ni}`
- Nickel-56 mass synthesized in the explosion.
* - ``M_ej``
- :math:`M_\mathrm{ej}`
- Ejecta mass.
* - ``v_ej``
- :math:`v_\mathrm{ej}`
- Ejecta velocity, taken to be constant and equal to the photospheric velocity.
* - ``kappa``
- :math:`\kappa`
- Grey optical opacity.
* - ``kappa_gamma``
- :math:`\kappa_\gamma`
- Opacity to high-energy photons. Fixed.
* - ``T_floor``
- :math:`T_\mathrm{floor}`
- Minimum photospheric temperature.
References
----------
.. footbibliography::
"""
_DEFAULT_PARAMETERS: ClassVar[dict[str, Parameter]] = {
"M_Ni": Parameter(
prior=TruncatedNormalPrior(mean=0.33, sigma=0.24, lower=0.02, upper=2.0),
scale=1 * u.Msun,
description="Nickel-56 mass synthesized in the explosion.",
latex=r"M_\mathrm{Ni}",
),
"M_ej": Parameter(
prior=TruncatedNormalPrior(mean=2.54, sigma=1.95, lower=0.1, upper=10.0),
scale=1 * u.Msun,
description="Ejecta mass.",
latex=r"M_\mathrm{ej}",
),
"v_ej": Parameter(
prior=TruncatedNormalPrior(mean=20.1, sigma=4.96, lower=5.0, upper=45.0),
scale=1e3 * u.km / u.s,
description="Constant ejecta velocity, identified with the photospheric velocity.",
latex=r"v_\mathrm{ej}",
),
"kappa": Parameter(
prior=UniformPrior(lower=0.05, upper=0.15),
scale=1 * u.cm**2 / u.g,
description="Grey optical opacity.",
latex=r"\kappa",
),
"kappa_gamma": Parameter(
prior=ConstantPrior(value=1000.0),
scale=1 * u.cm**2 / u.g,
description="Opacity to high-energy photons. Fixed at a large value (full gamma-ray trapping).",
latex=r"\kappa_\gamma",
),
"T_floor": Parameter(
prior=TruncatedNormalPrior(mean=6000.0, sigma=1000.0, lower=3000.0, upper=10000.0),
scale=1 * u.K,
description="Minimum photospheric temperature.",
latex=r"T_\mathrm{floor}",
),
}
