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We study the reactions e + e − → e + e − η (′) in the single-tag mode and measure the γγ * → η (′) transition form factors in the momentum-transfer range from 4 to 40 GeV 2 . The analysis is based on 469 fb −1 of integrated luminosity collected at PEP-II with the BABAR detector at e + e − centerof-mass energies near 10.6 GeV.

Study of B → X u ℓν decays in BB events tagged by a fully reconstructed B-meson decay and determination of |V ub | We report measurements of partial branching fractions for inclusive charmless semileptonic B decays B → Xuℓν, and the determination of the CKM matrix element |V ub |. The analysis is based on a sample of 467 million Υ (4S) → BB decays recorded with the BABAR detector at the PEP-II e + e − storage rings. We select events in which the decay of one of the B mesons is fully reconstructed and an electron or a muon signals the semileptonic decay of the other B meson. We measure partial branching fractions ∆B in several restricted regions of phase space and determine the CKM element |V ub | based on different QCD predictions. For decays with a charged lepton momentum p

, where the photon is radiated from the initial state. About 84000, 8000, and 4200 fully-reconstructed events, respectively, are selected from 454 fb −1 of BABAR data. The invariant mass of the hadronic final state defines the e + e − center-of-mass energy, so that the K + K − π + π − γ data can be compared with direct measurements of the e + e − → K + K − π + π − reaction. No direct measurements exist for the e + e − → K + K − π 0 π 0 or e + e − → K + K − K + K − reactions, and we present an update of our previous result based on a data sample that is twice as large. Studying the structure of these events, we find contributions from a number of intermediate states, and extract their cross sections. In particular, we perform a more detailed study of the e + e − → φ(1020)ππγ reaction, and confirm the presence of the Y (2175) resonance in the φ(1020)f0(980) and K + K − f0(980) modes. In the charmonium region, we observe the J/ψ in all three final states and in several intermediate states, as well as the ψ(2S) in some modes, and measure the corresponding products of branching fraction and electron width.