T2K Collaboration(Abe, K. et al), Cervera-Villanueva, A., Izmaylov, A., Novella, P., & Sorel, M. (2017). Updated T2K measurements of muon neutrino and antineutrino disappearance using 1.5 x 10(21) protons on target. Phys. Rev. D, 96(1), 011102–9pp.
Abstract: We report measurements by the T2K experiment of the parameters theta(23) and Delta m(32)(2) governing the disappearance of muon neutrinos and antineutrinos in the three-flavor neutrino oscillation model. Utilizing the ability of the experiment to run with either a mainly neutrino or a mainly antineutrino beam, the parameters are measured separately for neutrinos and antineutrinos. Using 7.482 x 10(20) POT in neutrino running mode and 7.471 x 10(20) POT in antineutrino mode, T2K obtained sin(2) (theta(23)) = 0.51(-0.07)(+0.08) and Delta (m) over bar (2)(32) = (+0.15)(-2.53) -0.13 x 10(-3) eV(2)/c(4) for neutrinos, and sin(2) ((theta) over bar (23)) = 0.42(-0.07)(+0.25) and Delta(m) over bar (2)(32) = 2.55(-0.27)(+0.33) x 10(-3) eV(2)/c(4) for antineutrinos (assuming normal mass ordering). No significant differences between the values of the parameters describing the disappearance of muon neutrinos and antineutrinos were observed.
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CDF Collaboration(Aaltonen, T. et al), & Cabrera, S. (2010). Updated search for the flavor-changing neutral-current decay D-0 -> mu(+)mu(-) in p(p)over-bar collisions at root s=1.96 TeV. Phys. Rev. D, 82(9), 091105–8pp.
Abstract: We report on a search for the flavor-changing neutral-current decay D-0 -> mu(+)mu(-) in p (p) over bar collisions at root s = 1.96 TeV using 360 pb(-1) of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. A displaced vertex trigger selects long-lived D-0 candidates in the mu(+)mu(-), pi(+)pi(-), and K-pi(+) decay modes. We use the Cabibbo-favored D-0 -> K-pi(+) channel to optimize the selection criteria in an unbiased manner, and the kinematically similar D-0 -> pi(+)pi(-) channel for normalization. We set an upper limit on the branching fraction B(D-0 -> mu(+)mu(-)) < 2.1 X 10(-7) (3.0 X 10(-7)) at the 90% (95%) confidence level.
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Das, D., & Santamaria, A. (2016). Updated scalar sector constraints in the Higgs triplet model. Phys. Rev. D, 94(1), 015015–10pp.
Abstract: We show that in the Higgs triplet model, after the Higgs discovery, the mixing angle in the CP-even sector can be strongly constrained from unitarity. We also discuss how large quantum effects in h -> gamma gamma may arise in a Standard-Model-like scenario and a certain part of the parameter space can be ruled out from the diphoton signal strength. Using T-parameter and diphoton signal strength measurements, we update the bounds on the nonstandard scalar masses.
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Karan, A., Miralles, V., & Pich, A. (2024). Updated global fit of the aligned two-Higgs-doublet model with heavy scalars. Phys. Rev. D, 109(3), 035012–29pp.
Abstract: An updated global fit on the parameter-space of the aligned two-Higgs-doublet model is performed with the help of the open-source package HEPfit, assuming the Standard-Model Higgs to be the lightest scalar. No new sources of CP violation, other than the phase in the Cabibbo-Kobayashi-Maskawa matrix of the Standard Model, are considered. A similar global fit was previously performed by O. Eberhardt et al. [Global fits in the aligned two-Higgs-doublet model, J. High Energy Phys. 05 (2021) 005] with a slightly different set of parameters. Our updated fit incorporates improved analyses of the theoretical constraints required for the perturbative unitarity and boundedness of the scalar potential from below, additional flavor observables and updated data on direct searches for heavy scalars at the LHC, Higgs signal strengths, and electroweak precision observables. Although not included in the main fit, the implications of the CDF measurement of the W +/- mass are also discussed.
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LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., et al. (2018). Updated determination of D-0-(D)over-bar(0) mixing and CP violation parameters with D-0 -> K+ pi(-) decays. Phys. Rev. D, 97(3), 031101–11pp.
Abstract: We report measurements of charm-mixing parameters based on the decay-time-dependent ratio of D-0 -> K+pi(-) to D-0 -> K-pi(+) rates. The analysis uses a data sample of proton-proton collisions corresponding to an integrated luminosity of 5.0 fb(-1) recorded by the LHCb experiment from 2011 through 2016. Assuming charge-parity (CP) symmetry, the mixing parameters are determined to be x'(2) = (3.9 +/- 2.7) x 10(-5), y' = (5.28 +/- 0.52) x 10(-3), and R-D = (3.454 +/- 0.031) x 10(-3). Without this assumption, the measurement is performed separately for D-0 and (D) over bar (0) mesons, yielding a direct CP-violating asymmetry A(D) = (-0.1 +/- 9.1) x 10(-3), and magnitude of the ratio of mixing parameters 1.00 < vertical bar q/p vertical bar < 1.35 at the 68.3% confidence level. All results include statistical and systematic uncertainties and improve significantly upon previous single-measurement determinations. No evidence for CP violation in charm mixing is observed.
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Gonzalez-Alonso, M., Pich, A., & Rodriguez-Sanchez, A. (2016). Updated determination of chiral couplings and vacuum condensates from hadronic tau decay data. Phys. Rev. D, 94(1), 014017–14pp.
Abstract: We analyze the lowest spectral moments of the left-right two-point correlation function, using all known short-distance constraints and the recently updated ALEPH V – A spectral function from tau decays. This information is used to determine the low-energy couplings L-10 and C-87 of chiral perturbation theory and the lowest-dimensional contributions to the operator product expansion of the left-right correlator. A detailed statistical analysis is implemented to assess the theoretical uncertainties, including violations of quark-hadron duality.
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Lattanzi, M., Riemer-Sorensen, S., Tortola, M., & Valle, J. W. F. (2013). Updated CMB and x- and gamma-ray constraints on Majoron dark matter. Phys. Rev. D, 88(6), 063528–8pp.
Abstract: The Majoron provides an attractive dark matter candidate, directly associated with the mechanism responsible for spontaneous neutrino mass generation within the standard model SU(3)(c) circle times SU(2)(L) circle times U(1)(Y) framework. Here we update the cosmological and astrophysical constraints on Majoron dark matter coming from the cosmic microwave background and a variety of x- and gamma-ray observations.
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Dias, J. M., Toledo, G., Roca, L., & Oset, E. (2021). Unveiling the K-1(1270) double-pole structure in the (B)over-bar -> J/psi rho(K)over-bar and (B)over-bar -> J/psi(K)over-bar*pi decays. Phys. Rev. D, 103(11), 116019–13pp.
Abstract: By looking at the pseudoscalar-vector meson spectra in the (B) over bar -> J/psi rho(K) over bar and (B) over bar -> J/psi(K) over bar*pi weak decays, we theoretically investigate the double-pole structure of the K-1 (1270) resonance by using the chiral unitary approach to account for the final-state interactions between the pseudoscalar (P) and vector (V) mesons. The K-1 (1270) resonance is dynamically generated through these interactions in coupled channels and influences the shape of the invariant mass distributions under consideration. We show how these shapes are affected by the K-1 (1270) double-pole structure to confront the results from our model with future experiments that might investigate the PV spectra in these decays.
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Vagnozzi, S., Giusarma, E., Mena, O., Freese, K., Gerbino, M., Ho, S., et al. (2017). Unveiling nu secrets with cosmological data: Neutrino masses and mass hierarchy. Phys. Rev. D, 96(12), 123503–26pp.
Abstract: Using some of the latest cosmological data sets publicly available, we derive the strongest bounds in the literature on the sum of the three active neutrino masses, M-nu, within the assumption of a background flat Lambda CDM cosmology. In the most conservative scheme, combining Planck cosmic microwave background temperature anisotropies and baryon acoustic oscillations (BAO) data, as well as the up-to-date constraint on the optical depth to reionization (tau), the tightest 95% confidence level upper bound we find is M-nu < 0.151 eV. The addition of Planck high-l polarization data, which, however, might still be contaminated by systematics, further tightens the bound to M-nu < 0.118 eV. A proper model comparison treatment shows that the two aforementioned combinations disfavor the inverted hierarchy at similar to 64% C.L. and similar to 71% C.L., respectively. In addition, we compare the constraining power of measurements of the full- shape galaxy power spectrum versus the BAO signature, from the BOSS survey. Even though the latest BOSS full-shape measurements cover a larger volume and benefit from smaller error bars compared to previous similar measurements, the analysis method commonly adopted results in their constraining power still being less powerful than that of the extracted BAO signal. Our work uses only cosmological data; imposing the constraint M-nu > 0.06 eV from oscillations data would raise the quoted upper bounds by O(0.1 sigma) and would not affect our conclusions.
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Aguilar, A. C., Binosi, D., & Papavassiliou, J. (2012). Unquenching the gluon propagator with Schwinger-Dyson equations. Phys. Rev. D, 86(1), 014032–24pp.
Abstract: In this article we use the Schwinger-Dyson equations to compute the nonperturbative modifications caused to the infrared finite gluon propagator (in the Landau gauge) by the inclusion of a small number of quark families. Our basic operating assumption is that the main bulk of the effect stems from the "one-loop dressed'' quark loop contributing to the full gluon self-energy. This quark loop is then calculated, using as basic ingredients the full quark propagator and quark-gluon vertex; for the quark propagator we use the solution obtained from the quark-gap equation, while for the vertex we employ suitable Ansatze, which guarantee the transversality of the answer. The resulting effect is included as a correction to the quenched gluon propagator, obtained in recent lattice simulations. Our main finding is that the unquenched propagator displays a considerable suppression in the intermediate momentum region, which becomes more pronounced as we increase the number of active quark families. The influence of the quarks on the saturation point of the propagator cannot be reliably computed within the present scheme; the general tendency appears to be to decrease it, suggesting a corresponding increase in the effective gluon mass. The renormalization properties of our results, and the uncertainties induced by the unspecified transverse part of the quark-gluon vertex, are discussed. Finally, the gluon propagator is compared with the available unquenched lattice data, showing rather good agreement.
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