ATLAS Collaboration(Aad, G. et al), Alvarez Piqueras, D., Aparisi Pozo, J. A., Bailey, A. J., Barranco Navarro, L., Cabrera Urban, S., et al. (2019). Evidence for the production of three massive vector bosons with the ATLAS detector. Phys. Lett. B, 798, 134913–22pp.
Abstract: A search for the production of three massive vector bosons in proton-proton collisions is performed using data at root s = 13 TeV recorded with the ATLAS detector at the Large Hadron Collider in the years 2015-2017, corresponding to an integrated luminosity of 79.8 fb(-1). Events with two same-sign leptons l (electrons or muons) and at least two reconstructed jets are selected to search for WWW -> l nu l nu qq. Events with three leptons without any same-flavour opposite-sign lepton pairs are used to search for WWW > l nu l nu l nu, while events with three leptons and at least one same-flavour opposite-sign lepton pair and one or more reconstructed jets are used to search for WWZ -> l nu qqll. Finally, events with four leptons are analysed to search for WWZ > l nu l nu ll and WZZ > qqllll. Evidence for the joint production of three massive vector bosons is observed with a significance of 4.1 standard deviations, where the expectation is 3.1 standard deviations.
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Kang, S. K., Popov, O., Srivastava, R., Valle, J. W. F., & Vaquera-Araujo, C. A. (2019). Scotogenic dark matter stability from gauged matter parity. Phys. Lett. B, 798, 135013–10pp.
Abstract: We explore the idea that dark matter stability results from the presence of a matter-parity symmetry, arising naturally as a consequence of the spontaneous breaking of an extended SU(3) circle times SU(3)(L) circle times U(1)(X) circle times U(1)(N) electroweak gauge symmetry with fully gauged B-L. Using this framework we construct a theory for scotogenic dark matter and analyze its main features.
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Vicente, A. (2019). Higgs Lepton Flavor Violating Decays in Two Higgs Doublet Models. Front. Physics, 7, 174–13pp.
Abstract: The discovery of a non-zero rate for a lepton flavor violating decay mode of the Higgs boson would definitely be an indication of New Physics. We review the prospects for such signal in Two Higgs Doublet Models, in particular for Higgs boson decays into tau μfinal states. We will show that this scenario contains all the necessary ingredients to provide large flavor violating rates and still be compatible with the stringent limits from direct searches and low-energy flavor experiments.
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Xiao, C. W., Nieves, J., & Oset, E. (2019). Prediction of hidden charm strange molecular baryon states with heavy quark spin symmetry. Phys. Lett. B, 799, 135051–10pp.
Abstract: We have studied the meson-baryon S-wave interaction in the isoscalar hidden-charm strange sector with the coupled-channels, eta(c)Lambda, J/psi Lambda, (D) over bar Xi(c), (D) over bar (s)Lambda(c), (D) over bar Xi(c)', (D) over bar*Lambda(c), (D) over bar*Xi(c)', (D) over bar*Xi*(c) in J(p) = 1/2(-), J/psi Lambda, (D) over bar*Xi(c), (D) over bar (s)*Lambda(c), (D) over bar*Xi(c)', (D) over bar Xi(c)*, (D) over bar*Xi(c)* in 3/2(-) and (D) over bar*Xi(c)* in 5/2(-). We impose constraints of heavy quark spin symmetry in the interaction and obtain the non vanishing matrix elements from an extension of the local hidden gauge approach to the charm sector. The ultraviolet divergences are renormalized using the same meson-baryon-loops regulator previously employed in the non-strange hidden charm sector, where a good reproduction of the properties of the newly discovered pentaquark states is obtained. We obtain five states of 1/2(-), four of 3/2(-) and one of 5/2(-), which could be compared in the near future with forthcoming LHCb experiments. The 5/2(-), three of the 3/2(-) and another three of the 1/2(-) resonances are originated from isoscalar (D) over bar (()*())Xi(c)' and (D) over bar (()*()) Xi(c)* interactions. They should be located just few MeV below the corresponding thresholds (4446, 4513, 4588 and 4655 MeV), and would be SU(3)-siblings of the isospin 1/2 (D) over bar (()*())Sigma(()(c)*()) quasi-bound states previously found, and that provided a robust theoretical description of the P-c(4440), P-c(4457) and P-c(4312) LHCb exotic states. The another two 1/2(-) and 3/2(-) states obtained in this work are result of the (D) over bar (()*())Xi(c)- D-s(()*()) Lambda(c) coupled-channels isoscalar interaction, are significantly broader than the others, with widths of the order of 15 MeV, being (D) over bar (()(s)*())Lambda(c) the dominant decay channel.
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Papoulias, D. K., Kosmas, T. S., & Kuno, Y. (2019). Recent Probes of Standard and Non-standard Neutrino Physics With Nuclei. Front. Physics, 7, 191–25pp.
Abstract: We review standard and non-standard neutrino physics probes that are based on nuclear measurements. We pay special attention on the discussion of prospects to extract new physics at prominent rare event measurements looking for neutrino-nucleus scattering, such as the coherent elastic neutrino-nucleus scattering (CE nu NS) that may involve lepton flavor violation (LFV) in neutral-currents (NC). For the latter processes several appreciably sensitive experiments are currently pursued or have been planed to operate in the near future, like the COHERENT, CONUS, CONNIE, MINER, TEXONO, RED100, vGEN, Ricochet, NUCLEUS, etc. We provide a thorough discussion on phenomenological and theoretical studies, in particular those referring to the nuclear physics aspects in order to provide accurate predictions for the relevant experiments. Motivated by the recent discovery of CE nu NS at the COHERENT experiment and the active experimental efforts for a new measurement at reactor-based experiments, we summarize the current status of the constraints as well as the future sensitivities on nuclear and electroweak physics parameters, non-standard interactions, electromagnetic neutrino properties, sterile neutrinos and simplified scenarios with novel vector Z ' or scalar phi mediators. Indirect and direct connections of CE nu NS with astrophysics, direct Dark Matter detection and charge lepton flavor violating processes are also discussed.
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