NERO - A Post Maximum Supernova Radiation Transport Code

Abstract

The interpretation of supernova (SN) spectra is essential for deriving SN ejecta properties such as density and composition, which in turn can tell us about their progenitors and the explosion mechanism. A very large number of atomic processes are important for spectrum formation. Several tools for calculating SN spectra exist, but they mainly focus on the very early or late epochs. The intermediate phase, which requires a NLTE treatment of radiation transport has rarely been studied. In this paper we present a new SN radiation transport code, NERO, which can look at those epochs. All the atomic processes are treated in full NLTE, under a steady-state assumption. This is a valid approach between roughly 50 and 500 days after the explosion depending on SN type. This covers the post-maximum photospheric and the early and the intermediate nebular phase. As a test, we compare NERO to the radiation transport code of Jerkstrand et al. (2011) and to the nebular code of Mazzali et al. (2001). All three codes have been developed independently and a comparison provides a valuable opportunity to investigate their reliability. Currently, NERO is one-dimensional and can be used for predicting spectra of synthetic explosion models or for deriving SN properties by spectral modelling. To demonstrate this, we study the spectra of the 'normal' SN Ia 2005cf between 50 and 350 days after the explosion and identify most of the common SN Ia line features at post maximum epochs.

9 pages, 14 figures, submitted to MNRAS

References in corpus (6)

• Time Dependent Monte Carlo Radiative Transfer Calculations For 3-Dimensional Supernova Spectra, Lightcurves, and Polarization
• The 44Ti-powered spectrum of SN 1987A
• The properties of the "standard" type Ic supernova 1994I from spectral models
• ESC observations of SN 2005cf: II. Optical Spectroscopy and the high velocity features
• Atomic data from the Iron Project. LXIV. Radiative transition rates and collision strengths for Ca II
• On the gamma-ray emission of Type Ia Supernovae

Cited by in corpus (16)

• The progenitor mass of the Type IIP supernova SN 2004et from late-time spectral modeling
• The nebular spectra of SN 2012aw and constraints on stellar nucleosynthesis from oxygen emission lines
• Time Dependent Radiative Transfer Calculations for Supernovae
• Late-time spectral line formation in Type IIb supernovae, with application to SN 1993J, SN 2008ax, and SN 2011dh
• Using late-time optical and near-infrared spectra to constrain Type Ia supernova explosion properties
• Spectra of supernovae in the nebular phase
• PESSTO monitoring of SN 2012hn: further heterogeneity among faint type I supernovae
• Nebular spectra of pair-instability supernovae
• Multimessengers from core-collapse supernovae: multidimensionality as a key to bridge theory and observation
• Critical ingredients of supernova Ia radiative-transfer modeling
• Monte Carlo radiative transfer for the nebular phase of Type Ia supernovae
• How do Type Ia Supernova Nebular Spectra Depend on Explosion Properties? Insights from Systematic non-LTE Modeling
• [CoIII] versus NaID in type Ia supernova spectra
• Study of Supernovae Important for Cosmology
• Supernova Resonance--scattering Line Profiles in the Absence of a Photosphere
• Spectral synthesis techniques for supernovae and kilonovae