Ancient nova shells of RX Pup indicate evolution of mass transfer rate

TL;DR

This paper reports the discovery of three nova shells around RX Pup, revealing a significant increase in mass transfer rate over 10,000 years, and providing insights into long-term binary evolution.

Contribution

It presents the first observation of three nova shells around a single system, indicating long-term evolution of mass transfer rates in a symbiotic binary.

Findings

Discovery of ~1300 and ~7000-year-old nova shells around RX Pup.

Evidence of a three-epoch nova eruption history in RX Pup.

Increase in mass transfer rate by a factor of three over 10,000 years.

Abstract

RX Pup is a symbiotic binary which experienced a nova outburst in the 1970's. Here we report a discovery of a ~1300 year old nova shell around the system and a possible detection of a ~7000 year old nova shell. Together with the nova shell ejected in the 1970's this makes RX Pup the first system with three nova shells observed. This triad of eruptions suggests a change in the nova recurrence time. The most likely explanation is an alteration in the mass transfer rate attributed to evolutionary changes of the mass-donor in the system. Notably, comparative analyses with theoretical models indicate an increase in the average mass transfer rate by a factor of three over the past 10,000 years. This makes RX Pup a unique system, which allows us to probe millenium-scale evolution of mass transfer rates in binary systems.