TITLE: GCN CIRCULAR NUMBER: 6690 SUBJECT: Konus-A observation of GRB 070729 DATE: 07/07/31 12:33:00 GMT FROM: Valentin Pal'shin at Ioffe Inst S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P. Oleynik and M. Ulanov on behalf of the Konus-A team report: The short hard GRB 070729 (Swift-BAT trigger #286373: Guidorzi et al., GCN 6678; Sato et al., GCN 6681), triggered Konus-A (Cosmos-2421) at T0=1554.9 s UT (00:25:54.9). As observed by Konus-A the burst had a fluence of 5.59(-4.38, +0.05)x10^-7 erg/cm2, and a 64-ms peak flux measured from T0-0.840 s of 1.07(-0.92, +0.38)x10^-6 erg/cm2/s (both in the 20 keV - 1 MeV energy range). Preliminary analysis shows that the time-integrated spectrum of the burst (from T0-1 s to T0) can be fitted (in the 20 keV - 1 MeV range) by a power law with exponential cutoff model: dN/dE ~ E^(-alpha)*exp(-E*(2-alpha)/Ep) with alpha = 1.08 (-0.36, +0.28) and Ep = 467(-195, +848) keV (chi2 = 36/48 dof). All the quoted errors are at the 90% confidence level.