2S 1845-024

Also known as: GX 1843-02 Simbad

Monitoring data: Swift/BAT Monitored but not detected by Fermi/GBM

RA	18h 48m 17.7s	Dec	-02° 25' 13"
l	30.4197	b	-0.4046

Orbit and Pulse

Very regular outbursts every 242d indicate orbital period, making it similar to GRO J1008-57. Orbit determined by Finger et al (1999):

Period	242.180 ± 0.012 days
T0	JD 2449616.98 ± 0.18
a sin i	689 ± 38 lt-s
e	0.8792 ± 0.0054
ω	252.2 ± 9.4

Pulse period about 94s (no recent measurement available).

Available data

• RXTE in 1998 and 2000 (PI Mark Finger)
• Chandra 55ks total (PI Mark Finger)
• XMM 40ks total
• many INTEGRAL SCWs
• sometimes in FOV of Swift

Literature

This is likely an incomplete list!

• Makino (1988) - Discovery (GS 1843-024)
• Zhang el al. (1996) - 2nd discovery (GRO 1849-03), BATSE-spectra
• Soffitta et al. (1998) - classification as BeXRTB
• Finger et al. (1999) - orbital parameters, pulse profiles, association with SAS-3 source (2S 1854-024)
• Doroshenko et al. (2008) - INTEGRAL data, fitted with simple power-law (no cutoff)