The Pion-Photon Transition Form Factor and New Physics in the Tau Sector

Recent measurement of the $\gamma\gamma^\ast$ form factor of the neutral pion in the high $Q^2$ region disagrees with {\em a priori} predictions of QCD-based calculations. We comment on existing explanations, and analyze a possibility that this discrepancy is not due to poorly understood QCD effects, but is a result of some new physics beyond the standard model (SM). We show that such physics would necessarily involve a new neutral light state with mass close to the mass of $\pi^0$, and with stronger than $\pi^0$ couplings to heavier SM flavors such as $c$, $\tau$, and $b$. It is found that only the coupling to the $\tau$ lepton can survive the existing constraints and lead to the observed rise of the pion form factor relative to $Q^{-2}$ at high $Q^2$. We perform numerical fits to data and determine the allowed range of masses and couplings for such new particles. This range of masses and couplings could also reduce or eliminate the tension between the $e^+e^-$ and $\tau$ decay determinations of the hadronic vacuum polarization. Dedicated experimental analysis of $\tau$ pair production in association with such new states should provide a conclusive test of the new physics hypothesis as an explanation to the pion form factor rise. We also comment on the calculations of the pion form factor in the chiral quark model, and point out a possible dynamical origin of the quark mass scale inferred from the form factor measurement.Comment: 13 pages, 6 figures, revtex4-1; v2: additional references, improved discussion of pion mixing case, published versio

Magnetic Induction Wand Design for Novel Penile Prosthesis​

Uronext LLC designed a novel penile prosthesis made of the shape change alloy nitinol for men who suffer from erectile dysfunction. The optimal way to induce the shape change in the prosthesis is by applying heat through induction heating. Existing induction heaters are too heavy and too powerful to safely and effectively heat the Uronext implanted penile prosthesis. An induction heating wand was made to combat this issue and provide a more appropriate induction heating device. A test bench was designed to test the effectiveness of the wand on the prosthesis

Tau and muon pair production cross-sections in electron-positron annihilations at sqrt{s} = 10.58 GeV

The calculational precision of \ee\to\tautau and \ee\to\mumu production cross-sections in electron-positron annihilations at \roots = 10.58 \gev are studied for the \kk Monte Carlo simulation program. We determine \sigma(\ee\to\tautau) = (0.919 \pm 0.003) \nb and \sigma(\ee\to\mumu) = (1.147 \pm 0.005) \nb, where the error represents the precision of the calculation.Comment: 7 pages, 3 tables, 1 figure (published in Physical Review D 77, 054012 (2008)

Toward testing the magnetic moment of the tau at one part per million

If physics beyond the Standard Model (BSM) explains the 4.2 σ difference between the Standard Model and measured muon anomalous magnetic moment a μ , minimal flavor violation predicts a shift in the analog quantity for the τ lepton a τ at the 10 − 6 level, and even larger effects are possible in generic BSM scenarios such as leptoquarks. We show that this produces equivalent BSM deviations in the Pauli form factor F 2 ( s ) at s = ( 10  GeV ) 2 and report the first complete two-loop prediction of Re F eff 2 ( 100 GeV 2 ) = − 268.77 ( 50 ) × 10 − 6 for resonant τ -pair production in e + e − → Υ ( n S ) → τ + τ − , = 1 , 2, 3. Re  F eff 2 can be measured from e − -helicity-dependent transverse and longitudinal asymmetries in τ -pair events, which requires a longitudinally polarized e − beam. We discuss how Belle II asymmetry measurements could probe a BSM τ at 10 − 6 , assuming such a polarization upgrade of the SuperKEKB e + e − collider, and conclude by outlining the next steps to be taken in theory and experiment along this new avenue for exploring realistic BSM effects in a τ

Systematic bias in surgeons' predictions of the donor‐specific risk of liver transplant graft failure

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/99664/1/lt23683.pd