Analysis on RXTE, INTEGRAL and ROTSE IIId observations of the X-ray Pulsar 4U 1907+09

TL;DR

This study combines RXTE, INTEGRAL, and ROTSE IIId data to analyze the timing, spectral properties, and optical behavior of the X-ray pulsar 4U 1907+09, providing an updated pulse period history and optical light curve.

Contribution

It offers a comprehensive timing and spectral analysis with an extended pulse period history and optical light curve, integrating multi-instrument observations for the first time.

Findings

Extended pulse period history of 4U 1907+09

Revised orbital distribution of X-ray dips

Long-term optical light curve of the source

Abstract

In this paper we present our recent timing and spectral analysis of the X-ray pulsar 4U 1907+09. Our X-ray data consist of an extended set of RXTE & INTEGRAL observations that were analyzed before ({\c{S}}ahiner et al. 2012). From the X-ray observations we extend the pulse period history of the source and obtain a revised orbital distribution of the X-ray dips. Using ROTSE IIId optical observations, we present the long term optical light curve of the source to have an understanding of long term optical behaviour.