T. AFFOLDER et al.PHYSICAL REVIEW D 65 052006 052006-2We have searched for evidence of physics beyond the standard model in events that include an energetic photon and an energetic b-quark jet, produced in 85 pb Ϫ1 of p p collisions at 1.8 TeV at the Tevatron Collider at Fermilab. This signature, containing at least one gauge boson and a third-generation quark, could arise in the production and decay of a pair of new particles, such as those predicted by supersymmetry, leading to a production rate exceeding standard model predictions. We also search these events for anomalous production of missing transverse energy, additional jets and leptons (e, and ), and additional b quarks. We find no evidence for any anomalous production of ␥b or ␥bϩX events. We present limits on two supersymmetric models: a model where the photon is produced in the decay 2 0 →␥ 1 0 , and a model where the photon is produced in the neutralino decay into the gravitino LSP, 1 0 →␥G . We also present our limits in a modelindependent form and test methods of applying model-independent limits.

We study the production of gravitational waves from primordial scalar perturbations in doubleinflection-point inflation, in which one of the inflection points predicts the power spectra consistent with CMB observations at large scales and the other generates a large peak in the power spectrum of scalar perturbations at small scales. We calculate the energy spectrum of the reduced gravitational waves and find that the gravitational-wave signal can be detected by future space-based laser interferometers. * xwutao@itp.ac.cn