Studies of Exclusive e+e- -> hadrons Reactions with Baryons and Strange Particles Using Initial State Radiation at Babar

New Babar results on exclusive e+e- -> hadrons reactions at low c.m. energy with a baryon-antibaryon or K\bar{K} pair in the final state are presented. Cross sections are measured using the initial state radiation technique from the threshold up to 4--5 GeV. From the measured e+e- -> proton\antiproton, Lambda\Lbar, Sigma0\Sigbar0, Lambda\Sigbar0(Sigma0\Lbar) cross sections we derive effective baryon form factors and compare them with predictions. We measure the K\bar{K}\pi(\eta), K+K-\pi\pi, K+K-3\pi, K+K-4\pi, K+K-K+K- final states and also study their internal structure. A new Y(2175) state is observed in e+e- -> K+K-f0(980), with f0\to\pi\pi. The total measured e+e- annihilation cross section into final states including strange baryons or strange mesons is estimated to be 10% of the full hadronic cross section.Comment: Talk at HADRON07 Conferenve, Frascati, October 8-13, 2007, 8 page

Coulomb effects in the spin-dependent contribution to the intra-beam scattering rate

Coulomb effects in the intra-beam scattering are taken into account in a way providing correct description of the spin-dependent contribution to the beam loss rate. It allows one to calculate this rate for polarized $e^{\pm}$ beams at arbitrarily small values of the ratio $\delta \varepsilon/\varepsilon$, characterizing relative change of the electron energy in the laboratory system during scattering event.Comment: 8 pages, 2 figure

Beam energy measurement at linear colliders using spin precession

Linear collider designs foresee some bends of about 5-10 mrad. The spin precession angle of one TeV electrons on 10 mrad bend is 23.2 rad and it changes proportional to the energy. Measurement of the spin direction using Compton scattering of laser light on electrons before and after the bend allows determining the beam energy with an accuracy about of 10^{-5}. In this paper the principle of the method, the procedure of the measurement and possible errors are discussed. Some remarks about importance of plasma focusing effects in the method of beam energy measurement using Moller scattering are given.Comment: 7 pages, Latex, 4 figures(.eps). In v.3 corresponds to journal publication. Talk at 26-th Advanced ICFA Beam Dynamic Workshop on Nanometre-Size Colliding Beams (Nanobeam2002), Lausanne, Switzerland, Sept 2-6, 200

Introducing a spread into the Kyle model

The Kyle (1985) model is extended to take into account market maker competition and the spread. It is shown that with a spread the Kyle model has a Nash equilibrium also with two market makers, not only with three or more, as shown in earlier research. The spread is endogenized, and two testable predictions of the model are generated. The first is that the spread is increasing in the standard deviation of the fundamentals. The second is that it is independent of the standard deviation of noise trades.market microstructure; spread; market maker;