Batse search for the similar to 540 keV feature in the Crab spectrum observed by Granat-SIGMA

We report the first simultaneous observations of the gamma -ray spectrum of the Crab in the energy range 25-1.7 MeV made by the BATSE and SIGMA experi ments. These observations were made on 1992 March 10-11. We report specific ally results of a search in the JPL BATSE Earth Occultation database for th e transient high-energy feature at similar to 540 keV reported by Granat-SI GMA during this period. We obtain a null result for this feature on both Ma rch 10 and March 11. The time-averaged continuum spectrum in the 25 keV-MeV range for the 2 day average spectrum is consistent with a single power law , with photon index of 2.25 +/-0.02. The best-fit line flux for either a na rrow (0 keV FWHM) feature at 541 keV or a broad (44 keV FWHM) feature at 53 6 keV of the same 2 day spectrum is (-1.2 +/-0.8) x 10(-3) and (-1.3 +/-0.8 ) x 10(-3) photons cm(-2) s(-1), compared to (4.3 +/-1.2) x 10(-3) and (5.1 +/-1.7) x 10(-3) photons cm(-2) s(-1), respectively, reported by the SIGMA investigators. The difference of the line fluxes measured simultaneously b y the BATSE and SIGMA experiments is estimated to be 3.8 a significance for the narrow feature and 3.4 sigma significance for the broad feature.