Investigation of WZ Sge-type Dwarf Nova ASASSN-19oc:Optical Spectroscopy and Multicolor Light Curve Analysis  

作　　者：Viktoriia Krushevska Sergey Shugarov Paolo Ochner Yuliana Kuznyetsova Mykola Petrov Peter Kroll 

机构地区：[1]Astronomical Institute of the Slovak Academy of Sciences,Tatranska Lomnica,05960 VysokéTatry,Slovakia [2]Main Astronomical Observatory of NAS of Ukraine,27 Akademika Zabolotnoho St.,03143 Kyiv,Ukraine [3]INAF—Osservatorio Astronomico di Padova,Vicolo dell’Osservatorio 5,I-35122 Padova,Italy [4]Department of Physics and Astronomy,University of Padova,Via F.Marzolo 8,I-35131 Padova,Italy [5]Max Planck Computing and Data Facility(MPCDF),Gießenbachstrasse 2,D-85748 Garching,Germany [6]Sonneberg Observatory,Sternwartestr.32,D-96515 Sonneberg,Germany

出　　处：《Research in Astronomy and Astrophysics》2024年第8期20-31,共12页天文和天体物理学研究（英文版）

基　　金：financial support of the APVV-20-0148,VEGA 2/0030/21 and VEGA 2/0031/22grants;support from the Government Office of the Slovak Republic within EU NextGenerationEU through the Recovery and Resilience Plan for Slovakia under the project No.09I03-03-V01-00002;the private company 4pi Systeme GmbH for partial sponsorship。

摘　　要：In this study,we present an investigation of the newly discovered dwarf nova ASASSN-19oc during its superoutburst on 2019 June 2.We carried out detailed UBVRcIc-photometric observations and also obtained a spectrum on day 7 of the outburst,which shows the presence of hydrogen absorption lines commonly found in dwarf nova outbursts.Analysis of photometric data reveals the occurrence of early superhumps in the initial days of observations,followed by ordinary and late superhumps.We have accurately calculated the period of the ordinary superhumps as Pord=0.05681(10)days and determined the periods at different stages,as well as the rate of change of the superhump period(P_(dot)=(5)P/P=8.1×10^(-5)).Additionally,we have derived the mass ratio of the components(q=0.09),and estimated the color temperature during the outburst as~11,000 K,the distance to the system(d=560 pc)and absolute magnitude of the system in outburst(MV=5.3).We have shown that outbursts of this star are very rare:based on brightness measurements on 600 archival photographic plates,we found only one outburst that occurred in 1984.This fact,as well as the properties listed above,convincingly shows that the variable ASASSN-19oc is a dwarf nova of WZ Sge type.

关 键 词：(stars)binaries(including multiple) close-(stars)novae-cataclysmic variables-stars dwarf novae 

分 类 号：P152[天文地球—天文学]