Astron. Astrophys. 364, 165-169 (2000)

7. Conclusions

We have detected VHE gamma ray emission from Cen X-3 during each dark moon period that we have observed this object. The data are consistent with a weak but persistent emission, both when the VHE data is averaged over dark moon periods and when considered observation by observation. Although the observation that yields the strongest gamma ray flux occurs on the day when the daily averaged RXTE X-ray flux was the highest of any day on which we observed Cen X-3, there is no evidence for a formal correlation between the VHE gamma-ray and X-ray fluxes.

We have also tested for modulation of the VHE gamma ray flux at the orbital period of the binary system and at the pulsar period. We have no evidence for modulation of the VHE gamma ray emission at either period.

The model of Katz and Smith (Katz & Smith 1988; Smith et al. 1992) for VHE gamma ray production in X-ray binaries is shown to be consistent with the VHE observations, especially in the light of its prediction of kHz fluctuations in X-ray intensity which have been observed during one of the epochs of VHE emission (Jernigan et al. 2000). As well as gamma ray emission at EGRET energies, the Katz and Smith model predicts an infrared excess from Cen X-3. It is suggested that IR observations of Cen X-3 should be made, especially as part of future multiwavelength studies.

© European Southern Observatory (ESO) 2000

Online publication: December 15, 2000
helpdesk.link@springer.de