X Sgr X-4 / 4U 1820-30

DSS color 2MASS AllWISE GLIMPSE 360 XMM Chandra

This webpage is powered by Aladin Lite v3.
Aladin Lite is developed and maintained by Thomas Boch and Matthieu Baumann. Contact at cds-question@unistra.fr.

Binary

Orbital Period: 0.19211111$\pm$0.000194 hr [2023ApJ...951...42C]
Eccentricity:
Radial Velocity:

Donor

Spectral Type: WD [1987ApJ...322..842R]
Mo: 0.065$\pm$0.015 M$_{\odot}$ [1987ApJ...322..842R]

Accretor

Type: NS [1976ApJ...205L.127G]
Mx: 1.3$\pm$0.6 M$_{\odot}$ [2011MNRAS.415.3344K]
Spin Period:
X-ray Bursts: yes [1976ApJ...205L.127G]