Long-term Optical Studies of the Be/X-ray Binary RX J0440.9+4431/LS V+44 17

Jingzhi Yan, Peng Zhang, Wei Liu +1

We present the spectroscopic and photometric observations on the Be/X-ray binary RX~J0440.9+4431 from 2001 to 2014. The short-term and long-term variability of the H$\alpha$ line profil…