# A Radio Emission Analysis of Classical Nova V351 Pup (1991)

## TL;DR

This study reanalyzes unpublished radio data of Nova V351 Pup, modeling its ejecta to estimate mass and distance, and infers the white dwarf's high mass, contributing to understanding nova ejecta characteristics.

## Contribution

It provides the first comprehensive analysis of all available radio data for V351 Pup, estimating ejecta mass and distance, and supports the presence of a very massive white dwarf.

## Key findings

- Ejecta mass estimated at 10^-5.2 solar masses.
- Distance to V351 Pup estimated at 5.0 ± 1.5 kpc.
- White dwarf inferred to be 1.25 solar masses.

## Abstract

Previously, Nova Puppis 1991 (V351 Pup) was measured to host one of the most massive ejections claimed in the literature. Multi-frequency radio detections from one epoch were published for this nova in the 1990's, and yet, the remaining data collected by the Very Large Array (VLA) have remained unpublished. In this paper, we analyze the remaining unpublished data sets for V351 Pup at frequencies of 4.9, 8.4, 14.9, and 22.5 GHz. We fit the resulting light curve to a model of expanding thermal ejecta, under the assumption that the radio emission is dominated by free-free radiation and accounting for high levels of clumping in the ejecta. Images of V351 Pup in both the radio (from the VLA) and H$\alpha$+[N II] (from HST) exhibit no aspherical structure, strengthening our assumption of spherical symmetry. From expansion parallax methods, we estimate the distance to V351 Pup to be $5.0 \pm 1.5$ kpc. Our light curve fit yields a value of $log_{10}(M_{ej})={-5.2} \pm {0.7}$ M$_{\odot}$ for the ejecta mass, implying that V351 Pup is on the low end of expectations for ejecta mass from classical novae. A comparison between our derived ejecta mass and theoretical models gives evidence for a very massive (1.25 M$_{\odot}$) white dwarf, which is consistent with spectroscopic evidence for an oxygen-neon white dwarf.