The first spectra for the RX J0440.9+4431 from 2m Terskol telescope

TL;DR

This paper reports the first spectral observations of the Be/X-ray binary RX J0440.9+4431 using the 2m Terskol telescope, revealing V/R variability and disc change timescales.

Contribution

First spectral analysis of RX J0440.9+4431 from the Terskol observatory, providing new insights into its emission line profiles and disc variability.

Findings

V/R variability in H-alpha line profile

Estimated disc change timescale of about 14 years

Comparison with previous spectral data

Abstract

We present the first results on the spectra of Be/X-ray binary RX J0440.9+4431 obtained with the 2m Ritchey-Cretein-Coude telescope with Cassegrain Multi Mode Spectrograph (CMMS) (with R = 14000) at Terskol observatory. The H-alpha line profile indicates that the new episode of the V/R variability is occuring in the system. The profiles of the H-alpha, H-beta and HeI 7065.71, 6678.15, 5875.97 lines were analyzed and equivalent width were determined. We compared our H-alpha line profile parameters with the previous results from the literature and estimated characteristic time scale for disc changes as about 14 years.