Updated orbital ephemeris of the ADC source X 1822-371: a stable orbital expansion over 40 years

S. M. Mazzola, R. Iaria, T. Di Salvo +6

The source X 1822-371 is an eclipsing compact binary system with a period close to 5.57 hr and an orbital period derivative ${\dot{P}}_{\mathrm{orb}}$ of 1.51(7)$\times 10^{-10}$ s s$^{-1…