Asiago eclipsing binaries program. IV. SZ Camelopardalis, a beta Cephei pulsator in a quadruple, eclipsing system

TL;DR

This study analyzes the complex multiple system SZ Cam, revealing a beta Cephei pulsator within the system, and provides detailed spectroscopic and photometric characterization of its components and orbital dynamics.

Contribution

It offers the first detailed spectral disentangling and orbital solution of SZ Cam, identifying a beta Cephei pulsator in a quadruple eclipsing system.

Findings

Disentangled spectra of all components obtained.

Detected beta Cephei pulsation with a 0.33265-day period.

Derived atmospheric parameters consistent with orbital analysis.

Abstract

We present a spectroscopic and photometric analysis of the multiple system and early-type eclipsing binary SZ Cam (O9IV + B0.5V), which consists of an eclipsing SB2 pair of orbital period P=2.7 days in a long orbit (about 55 yrs) around a non-eclipsing SB1 pair of orbital period P=2.8 days. We have reconstructed the spectra of the individual components of SZ Cam from the observed composite spectra using the technique of spectral disentangling. We used them together with extensive and accurate BVI CCD photometry to obtain an orbital solution. Our photometry revealed the presence of a beta Cep variable in the SZ Cam hierarchical system, probably located within the non-eclipsing SB1 pair. The pulsation period is 0.33265+/-0.00005 days and the observed total amplitude in the B band is 0.0105 +/- 0.0005 mag. NLTE analysis of the disentangled spectra provided atmospheric parameters for all three components, consistent with those derived from orbital solution.