V341 Ara - The nova-like variable that has it all

Wednesday, 09 January 2019 8 a.m. — 9 a.m. MST

AURA Lecture Hall

NOIRLab South Colloquia
NOEL CASTRO-SEGURA (University of Southhampton and NOAO South Visiting PhD Student)

Non-magnetic nova-likes are cataclysmic variables with mass-transfer rates high enough to keep the accretion disk in a permanent high state. These systems are therefore great test beds for our understanding of steady-state accretion disks.V341 Arae is an 11th magnitude blue object embedded in a large (8' x 10') emission line nebula. [O III] images suggest a parabolic bow-shock shape for the nebula, with V341 near the apex. The ionized mass of the nebula is very low compared to the canonical PN, though is inline with the spected form an old nova shell.The source was long misclassified as a Cepheid variable and first revealed as a nova-like CV by Samus, Pastukhova & Durlevich (2007) and Frew (2008) independently. Even since then, it has remained surprisingly unnoticed by the CV community. Remarkably, even though V341 Ara is one of the brightest novalikes known, only the orbital period of the system is known. Here, we present results from a spectroscopic campaign we have been carrying out with the SAAO 1.9m telescope and time resolved spectroscopy carried out with the integral field unit WiFeS at SSO. This is supplemented by archival data obtained with the CTIO 1.5m and new observations gather with SALT. We also present the results from long-term photometric light curves obtained by the ASAS-SN and KELT surveys, which reveal long-term ( 10 day) super-orbital (quasi-)periodicities. With this data we will constrain the binary parameters, and discuss the origin of the nebula and its evolutionary stage of this peculiar source. In addition we present new UV and X-Ray spectroscopic observation carried out with SWIFT which allow us to study the interaction of the accretion disk with the circumstellar medium and help us to construct a full SED of the source.