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Campanario, F., Figy, T. M., Platzer, S., & Sjodahl, M. (2013). Electroweak Higgs Boson Plus Three Jet Production at Next-to-Leading-Order QCD. Phys. Rev. Lett., 111(21), 211802–4pp.
Abstract: We calculate next-to-leading order (NLO) QCD corrections to electroweak Higgs boson plus three jet production. Both vector boson fusion (VBF) and Higgs-strahlung type contributions are included along with all interferences. The calculation is implemented within the MATCHBOX NLO framework of the HERWIG++ event generator.
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Tain, J. L. et al, Valencia, E., Algora, A., Agramunt, J., Rubio, B., Estevez, E., et al. (2015). Enhanced gamma-Ray Emission from Neutron Unbound States Populated in beta Decay. Phys. Rev. Lett., 115(6), 062502–5pp.
Abstract: Total absorption spectroscopy is used to investigate the beta-decay intensity to states above the neutron separation energy followed by gamma-ray emission in Br-87,Br-88 and Rb-94. Accurate results are obtained thanks to a careful control of systematic errors. An unexpectedly large. intensity is observed in all three cases extending well beyond the excitation energy region where neutron penetration is hindered by low neutron energy. The gamma branching as a function of excitation energy is compared to Hauser-Feshbach model calculations. For Br-87 and Br-88 the gamma branching reaches 57% and 20%, respectively, and could be explained as a nuclear structure effect. Some of the states populated in the daughter can only decay through the emission of a large orbital angular momentum neutron with a strongly reduced barrier penetrability. In the case of neutron-rich Rb-94 the observed 4.5% branching is much larger than the calculations performed with standard nuclear statistical model parameters, even after proper correction for fluctuation effects on individual transition widths. The difference can be reconciled by introducing an enhancement of 1 order of magnitude in the photon strength to neutron strength ratio. An increase in the photon strength function of such magnitude for very neutron-rich nuclei, if it proves to be correct, leads to a similar increase in the (n, gamma) cross section that would have an impact on r process abundance calculations.
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MiniBooNE Collaboration(Aguilar-Arevalo, A. A. et al), & Sorel, M. (2010). Event Excess in the MiniBooNE Search for (nu)over-bar(mu) -> (nu)over-bar(e) Oscillations. Phys. Rev. Lett., 105(18), 181801–5pp.
Abstract: The MiniBooNE experiment at Fermilab reports results from a search for (nu) over bar (mu) -> (nu) over bar (e) oscillations, using a data sample corresponding to 5.66 x 10(20) protons on target. An excess of 20.9 +/- 14.0 events is observed in the energy range 475 < E-nu(QE) < 1250 MeV, which, when constrained by the observed <(nu)over bar>(mu) events, has a probability for consistency with the background-only hypothesis of 0.5%. On the other hand, fitting for (nu) over bar (mu) -> (nu) over bar (e) oscillations, the best-fit point has chi(2) probability of 8.7%. The data are consistent with (nu) over bar (mu) -> (nu) over bar (e) oscillations in the 0.1 to 1.0 eV(2) Delta m(2) range and with the evidence for antineutrino oscillations from the Liquid Scintillator Neutrino Detector at Los Alamos National Laboratory.
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LHCb Collaboration(Aaij, R. et al), Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., & Ruiz Vidal, J. (2022). Evidence for a New Structure in the J/psi p and J/psi(p)over-bar Systems in B-s(0) -> J/psi p(p)over-bar Decays. Phys. Rev. Lett., 128(6), 062001–11pp.
Abstract: An amplitude analysis of flavor-untagged B-s(0) -> J=psi p (p) over bar decays is performed using a sample of 797 +/- 31 decays reconstructed with the LHCb detector. The data, collected in proton-proton collisions between 2011 and 2018, correspond to an integrated luminosity of 9 fb(-1). Evidence for a new structure in the J=psi p and J=psi(p) over bar systems with a mass of 4337(-4-2)(+7+2) MeV and a width of 29(-12-14)(+26+14) MeV is found, where the first uncertainty is statistical and the second systematic, with a significance in the range of 3.1 to 3.7 sigma, depending on the assigned J(P) hypothesis.
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BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2012). Evidence for an Excess of (B)over-bar -> D-(*()) tau(-)(nu)over-bar(tau) Decays. Phys. Rev. Lett., 109(10), 101802–8pp.
Abstract: Based on the full BABAR data sample, we report improved measurements of the ratios R(D-(*())) = B((B) over bar -> D-(*()) tau(-)(nu) over bar (tau))/B((B) over bar -> D-(*()) l(l)(-)(nu) over bar (l), where l is either e or mu. These ratios are sensitive to new physics contributions in the form of a charged Higgs boson. We measure R(D) = 0.440 +/- 0.058 +/- 0.042 and R(D*) = 0.332 +/- 0.024 +/- 0.018, which exceed the standard model expectations by 2.0 sigma and 2.7 sigma, respectively. Taken together, our results disagree with these expectations at the 3.4 sigma level. This excess cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model.
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