
LHCb Collaboration(Aaij, R. et al), MartinezVidal, F., Oyanguren, A., Ruiz Valls, P., & Sanchez Mayordomo, C. (2014). Measurement of CP violation parameters in B0 > DK*(0) decays. Phys. Rev. D, 90(11), 112002–14pp.
Abstract: An analysis of B0 > DK*(0) decays is presented, where D represents an admixture of D0 and (D) over bar (0) mesons reconstructed in four separate final states: Kpi(+), pi K(+), K+K and pi(+)pi(). The data sample corresponds to 3.0 fb(1) of protonproton collision, collected by the LHCb experiment. Measurements of several observables are performed, including CP asymmetries. The most precise determination is presented of r(B)(DK*(0)), the magnitude of the ratio of the amplitudes of the decay B0 > DK+pi() with a b > u or a b > c transition, in a K pi mass region of +/ 50 MeV/c(2) around the K*(892) mass and for an absolute value of the cosine of the K*(0) helicity angle larger than 0.4.



BABAR Collaboration(Lees, J. P. et al), MartinezVidal, F., & Oyanguren, A. (2014). Study of the reaction e(+)e() > psi(2S)pi(+)pi() via initialstate radiation at BABAR. Phys. Rev. D, 89(11), 111103–8pp.
Abstract: We study the process e(+)e() > psi(2S)pi(+)pi() with initialstateradiation events produced at the PEPII asymmetricenergy collider. The data were recorded with the BABAR detector at centerofmass energies at and near the (nS) (n = 2, 3, 4) resonances and correspond to an integrated luminosity of 520 fb(1). We investigate the psi(2S)pi(+)pi() mass distribution from 3.95 to 5.95 GeV/c(2), and measure the centerofmass energy dependence of the associated e(+)e() > psi(2S)pi(+)pi() cross section. The mass distribution exhibits evidence of two resonant structures. A fit to the psi(2S)pi(+)pi() mass distribution corresponding to the decay mode psi(2S) > J/psi pi(+)pi() yields a mass value of 4340 +/ 16 (stat) +/ 9 (syst) MeV/c(2) and a width of 94 +/ 32 (stat) +/ 13 (syst) MeV for the first resonance, and for the second a mass value of 4669 +/ 21 (stat) +/ 3 (syst) MeV/c(2) and a width of 104 +/ 48 (stat) +/ 10 (syst) MeV. In addition, we show the pi(+)pi() mass distributions for these resonant regions.



BABAR Collaboration(Lees, J. P. et al), MartinezVidal, F., Oyanguren, A., & VillanuevaPerez, P. (2014). Antideuteron production in Upsilon(nS) decays and in e(+)e() > q(q) over bar at root s approximate to 10.58 GeV. Phys. Rev. D, 89(11), 111102–8pp.
Abstract: We present measurements of the inclusive production of antideuterons in e(+)e() annihilation into hadrons at approximate to 10.58 GeV centerofmass energy and in Upsilon(1S, 2S, 3S) decays. The results are obtained using data collected by the BABAR detector at the PEPII electronpositron collider. Assuming a fireball spectral shape for the emitted antideuteron momentum, we find B(Upsilon(1S) > (d) over barX) = (2.81 +/ 0.49(stat)(+0.20)(0.24)(syst)) x 10(5), B(Upsilon(2S) > (d) over barX) = (2.64 +/ 0.11(stat)(0.21)(+0.26)(syst)) x 10(5), B(Upsilon(3S) > (d) over barX) = (2.33 +/ 0.15(stat)(0.28)(+0.31)(syst)) x 10(5), and sigma(e(+)e() > (d) over barX) = (9.63 +/ 0.41(stat)(1.01)(+1.17)(syst) fb.



Anderson, P. R., Balbinot, R., Fabbri, A., & Parentani, R. (2014). Graybody factor and infrared divergences in 1D BEC acoustic black holes. Phys. Rev. D, 90(10), 104044–6pp.
Abstract: It is shown that the graybody factor for a onedimensional elongated BoseEinstein condensate (BEC) acoustic black hole with one horizon does not vanish in the lowfrequency (omega > 0) limit. This implies that the analog Hawking radiation is dominated by the emission of an infinite number (1/omega) of soft phonons in contrast with the case of a Schwarzschild black hole where the graybody factor vanishes as omega > 0 and the spectrum is not dominated by lowenergy particles. The infrared behaviors of certain correlation functions are also discussed.



Boubekeur, L., Giusarma, E., Mena, O., & Ramirez, H. (2014). Current status of modified gravity. Phys. Rev. D, 90(10), 103512–10pp.
Abstract: We revisit the cosmological viability of the HuSawicki modified gravity scenario. The impact of such a modification on the different cosmological observables, including gravitational waves, is carefully described. The most recent cosmological data, as well as constraints on the relationship between the clustering parameter sigma(8) and the current matter massenergy density Omega(m) from cluster number counts and weak lensing tomography, are considered in our numerical calculations. The strongest bound we find is vertical bar f(R0)vertical bar < 3.7 x 10(6) at 95% C.L. Forthcoming cluster surveys covering 10 000 deg(2) in the sky, with galaxy surface densities of O(10) arcmin(2) could improve the precision in the sigma(8)Omega(m) relationship, tightening the above constraint.



RuizFemenia, P. (2014). First estimate of the NNLO nonresonant corrections to topantitop threshold production at lepton colliders. Phys. Rev. D, 89(9), 097501–4pp.
Abstract: We compute the dominant term in the expansion in rho = 1 – Mw/m(t) of the unknown nexttonexttoleading order nonresonant contributions to the e+ e() > W+ W b (b) over bar total cross section at energies close to the topantitop threshold. Our analytic result disagrees with a previous calculation by other authors [A. A. Penin and J. H. Piclum, J. High Energy Phys. 01 (2012) 034]. We show that our determination has the correct infrared structure needed to cancel the divergences proportional to the top width arising in the resonant production of the same final state, and we point to a missing contribution in the computation of Penin and Piclum to explain the discrepancy.



Bertolini, S., Maiezza, A., & Nesti, F. (2014). Present and future K and B meson mixing constraints on TeV scale leftright symmetry. Phys. Rev. D, 89(9), 095028–15pp.
Abstract: We revisit the Delta F = 2 transitions in the K and Bd,Bs neutral meson systems in the context of the minimal leftright symmetric model. We take into account, in addition to uptodate phenomenological data, the contributions related to the renormalization of the flavorchanging neutral Higgs treelevel amplitude. These contributions were neglected in recent discussions, albeit formally needed in order to obtain a gaugeindependent result. Their impact on the minimal LR model is crucial and twofold. First, the effects are relevant in B meson oscillations, for both CP conserving and CP violating observables, so that for the first time these imply constraints on the LR scenario which compete with those of the K sector (plagued by longdistance uncertainties). Second, they sizably contribute to the indirect kaon CP violation parameter epsilon. We discuss the bounds from B and K mesons in both cases of LR symmetry: generalized parity (P) and charge conjugation (C). In the case of P, the interplay between the CPviolation parameters epsilon and epsilon' leads us to rule out the regime of very hierarchical bidoublet vacuum expectation values nu(2)/nu(1) < m(b)/m(t) similar or equal to 0.02. In general, by minimizing the scalar field contribution up to the limit of the perturbative regime and by definite values of the relevant CP phases in the charged righthanded currents, we find that a righthanded gauge boson WR as light as 3 TeV is allowed at the 95% C. L. This is well within the reach of direct detection at the next LHC run. If not discovered, within a decade the upgraded LHCb and Super B factories may reach an indirect sensitivity to a leftright scale of 8 TeV.



Celis, A., Cirigliano, V., & Passemar, E. (2014). Modeldiscriminating power of lepton flavor violating tau decays. Phys. Rev. D, 89(9), 095014–14pp.
Abstract: Within an effective field theory framework, we discuss the possibility to discriminate among different operators that contribute to lepton flavor violating (LFV) tau decays. Correlations among decay rates in different channels are shown to provide a basic handle to unravel the origin of LFV in these processes. More information about the underlying dynamics responsible for LFV can be gathered from differential distributions in threebody decays like tau > μpi pi or tau > 3 mu: these are considered in some detail. We incorporate in our analysis recent developments in the determination of the hadronic form factors for tau > μpi pi. Future prospects for the observation of LFV tau decays and its interpretation are also discussed.



Park, J. H. (2014). Lepton flavor violation from righthanded neutrino thresholds. Phys. Rev. D, 89(9), 095005–6pp.
Abstract: Charged lepton flavor violation is reappraised in the context of a supersymmetric seesaw mechanism. It is pointed out that a nontrivial flavor structure of righthanded neutrinos, whose effect has been thus far less studied, can give rise to significant slepton flavor transitions. Under the premise that the neutrino Yukawa couplings are of O(1), the righthanded neutrino mixing contribution could form a basis of the μ> e gamma amplitude, which by itself might lead to an experimentally accessible rate, given a typical lowenergy sparticle spectrum. Emphasis is placed on the crucial role of the recently measured lepton mixing angle theta(13) as well as the leptonic CPviolating phases.



Maiezza, A., & Nemevsek, M. (2014). Strong P invariance, neutron electric dipole moment, and minimal leftright parity at LHC. Phys. Rev. D, 90(9), 095002–10pp.
Abstract: In the minimal leftright model the choice of leftright symmetry is twofold: either generalized parity P or charge conjugation C. In the minimal model with spontaneously broken strict P, a large treelevel contribution to strong CP violation can be computed in terms of the spontaneous phase alpha. Searches for the neutron electric dipole moments then constrain the size of alpha. Following the latest update on indirect CP violation in the kaon sector, a bound on WR mass at 20 TeV is set. Possible ways out of this bound require a further hypothesis, either a relaxation mechanism or explicit breaking of P. To this end, the chiral loop of the neutron electric dipole moment at nexttoleading order is recomputed and provides an estimate of the weak contribution. Combining this constraint with other CPviolating observables in the kaon sector allows for MWR greater than or similar to 3 TeV. On the other hand, C symmetry is free from such constraints, leaving the righthanded scale within the experimental reach.

