UY Puppis - A New Anomalous Z Cam Type Dwarf Nova

TL;DR

This paper identifies UY Puppis as one of the rare anomalous Z Cam type dwarf novae, exhibiting atypical standstill and outburst behavior, expanding understanding of Z Cam star variability.

Contribution

It provides the first detailed observational evidence that UY Pup is an anomalous Z Cam star, adding to the limited known cases and challenging previous classifications.

Findings

UY Pup entered a standstill after an outburst, contrary to expectations.

UY Pup exhibited two outbursts during its standstill, an unusual behavior.

UY Pup is confirmed as one of only four known anomalous Z Cam stars.

Abstract

The defining characteristic of Z Cam stars are standstills in their light curves. Some Z Cams exhibit atypical behaviour by going into outburst from a standstill. It has previously been suggested that UY Pup had been a Z Cam star, but it was ruled out due to its long-term light curve. However, in December 2015 UY Pup went into outburst and unexpectedly entered into a short standstill instead of returning to quiescence. Furthermore, UY Pup exhibited additional unusual behaviour with two outbursts detected during its standstill. After this standstill UY Pup made a brief excursion to a quiescence state and slowly rose to a longer and well-defined standstill, where it again went into another outburst. Through comparative analysis, research, and observational data of UY Pup it is evident and thus concluded that it is indeed a Z Cam star, in which renders it to be one of only four known anomalous Z Cam stars.