New accreting compact objects and interacting binaries in e-ROSITA DR1

We report the discovery of five new Cataclysmic Variables and several interacting binary systems identified through transient analysis comparing ROSAT and eROSITA (DR1) .We present for the first time the detailed spectral analysis in the energy range 0.1-10 KeV of Main Sequence stars, Giant stars, accreting compact object binary systems,Young Stellar objects, and Long period Variables (LPV). Notably, LPVs occupy the Supergiant branch in the Hertzsprung–Russell diagram and exhibit unique X-ray spectra with excess flux up to 0.5 keV and no significant emission beyond 2 keV. Our study also highlights the enhanced X-ray luminosity of Giant stars compared to Main Sequence stars, which prompt us to do the temporal analyses to investigate binarity. Clear signatures of companion stars with orbital periods of a few days are identified in Giant systems indicating these systems may be contact binaries. These findings provide new insights into the physical properties and diversity of X-ray transients in binary and compact object systems.