An anomalous low-state from the globular cluster X-ray source X 1732-304 (Terzan 1)

During a BeppoSAX observation of the X-ray burst source X 1732-304 located in the globular cluster Terzan I in April 1999, the source was detected in an anomalous low-state with an X-ray luminosity of 1.4 x 10(33) erg s(-1), about 300 times fainter than the lowest previously reported measure of the persistent flux. The spectral shape and intensity of this low-state emissio n is similar to that of a number of neutron star soft X-ray transients in q uiescence, being well fit by a similar or equal to 0.34 keV blackbody toget her with a power-law with a photon index of 1.0+/-(1.0)(1.3) .These similar ities suggest that the same mechanism, such as the inhibition of accretion due to the propeller effect, is also operating in X 1732-304. Alternatively , the X 1732-304 low-state may be due to obscuration of the line of sight t o the central neutron star, with only scattered and/or reflected X-rays bei ng detected. The possibility that the source detected by BeppoSAX is not X 1732-304, but a nearby dim source of the cluster field (what would make the observed dimming of X 1732-304 even more remarkable) is also discussed.