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Raj, N., Takhistov, V., & Witte, S. J. (2020). Presupernova neutrinos in large dark matter direct detection experiments. Phys. Rev. D, 101(4), 043008–10pp.
Abstract: The next Galactic core-collapse supernova (SN) is a highly anticipated observational target for neutrino telescopes. However, even prior to collapse, massive dying stars shine copiously in “pre-supernova” (pre-SN) neutrinos, which can potentially act as efficient SN warning alarms and provide novel information about the very last stages of stellar evolution. We explore the sensitivity to pre-SN neutrinos of large-scale direct dark matter detection experiments, which, unlike dedicated neutrino telescopes, take full advantage of coherent neutrino-nucleus scattering. We find that argon-based detectors with target masses of O(100)tons (i.e., comparable in size to the proposed ARGO experiment) operating at sub-keV thresholds can detect O(10-100) pre-SN neutrinos coming from a source at a characteristic distance of similar to 200 pc, such as Betelgeuse (alpha Orionis). Large-scale xenon-based experiments with similarly low thresholds could also be sensitive to pre-SN neutrinos. For a Betelgeuse-type source, large-scale dark matter experiments could provide a SN warning siren similar to 10 hours prior to the explosion. We also comment on the complementarity of large-scale direct dark matter detection experiments and neutrino telescopes in the understanding of core-collapse SN.
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LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., et al. (2020). Determination of quantum numbers for several excited charmed mesons observed in B- -> D*(+)pi(-) pi(-) decays. Phys. Rev. D, 101(3), 032005–24pp.
Abstract: A four-body amplitude analysis of the B- -> D*(+)pi(-) pi(-) decay is performed, where fractions and relative phases of the various resonances contributing to the decay are measured. Several quasi-model-independent analyses are performed aimed at searching for the presence of new states and establishing the quantum numbers of previously observed charmed meson resonances. In particular the resonance parameters and quantum numbers are determined for the D-1 (2420), D-1 (2430), D-0 (2550), D-1* (2600), D-2 (2740) and D-3*(2750) states. The mixing between the D-1 (2420) and D-1 (2430) resonances is studied and the mixing parameters are measured. The dataset corresponds to an integrated luminosity of 4.7 fb(-1), collected in proton-proton collisions at center-of-mass energies of 7, 8 and 13 TeV with the LHCb detector.
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Centelles Chulia, S., Rodejohann, W., & Saldana-Salazar, U. J. (2020). Two-Higgs-doublet models with a flavored Z(2) symmetry. Phys. Rev. D, 101(3), 035013–12pp.
Abstract: Two-Higgs-doublet models usually consider an ad-hoc Z(2) discrete symmetry to avoid flavor changing neutral currents. We consider a new class of two-Higgs-doublet models where Z(2) is enlarged to the symmetry group F(sic)Z(2), i.e., an inner semidirect product of a discrete symmetry group F and Z(2). In such a scenario, the symmetry constrains the Yukawa interactions but goes unnoticed by the scalar sector. In the most minimal scenario, Z(3)(sic)Z(2) = D-3, flavor changing neutral currents mediated by scalars are absent at tree and one-loop level, while at the same time predictions to quark and lepton mixing are obtained, namely a trivial Cabibbo-Kobayashi-Maskawa matrix and a Pontecorvo-Maki-Nakagawa-Sakata matrix (upon introduction of three heavy right-handed neutrinos) containing maximal atmospheric mixing. Small extensions allow to fully reproduce mixing parameters, including cobimaximal mixing in the lepton sector (maximal atmospheric mixing and a maximal charge-parity violating phase).
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Bonilla, C., Centelles Chulia, S., Cepedello, R., Peinado, E., & Srivastava, R. (2020). Dark matter stability and Dirac neutrinos using only standard model symmetries. Phys. Rev. D, 101(3), 033011–5pp.
Abstract: We provide a generic framework to obtain stable dark matter along with naturally small Dirac neutrino masses generated at the loop level. This is achieved through the spontaneous breaking of the global U(1)(B-L) symmetry already present in the standard model. The U(1)(B-L) symmetry is broken down to a residual even Z(n) (n >= 4) subgroup. The residual Z(n) symmetry simultaneously guarantees dark matter stability and protects the Dirac nature of neutrinos. The U(1)(B-L) symmetry in our setup is anomaly free and can also be gauged in a straightforward way. Finally, we present an explicit example using our framework to show the idea in action.
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Di Valentino, E., Melchiorri, A., Mena, O., & Vagnozzi, S. (2020). Nonminimal dark sector physics and cosmological tensions. Phys. Rev. D, 101(6), 063502–20pp.
Abstract: We explore whether nonstandard dark sector physics might be required to solve the existing cosmological tensions. The properties we consider in combination are (a) an interaction between the dark matter and dark energy components and (b) a dark energy equation of state w different from that of the canonical cosmological constant w = -1. In principle, these two parameters are independent. In practice, to avoid early-time, superhorizon instabilities, their allowed parameter spaces are correlated. Moreover, a clear degeneracy exists between these two parameters in the case of cosmic microwave background (CMB) data. We analyze three classes of extended interacting dark energy models in light of the 2019 Planck CMB results and Cepheid-calibrated local distance ladder H-0 measurements of Riess et al. (R19), as well as recent baryon acoustic oscillation (BAO) and type Ia supernovae (SNeIa) distance data. We find that in quintessence coupled dark energy models, where w > -1, the evidence for a nonzero coupling between the two dark sectors can surpass the 5 sigma significance. Moreover, for both Planck + BAO or Planck + SNeIa, we find a preference for w > -1 at about three standard deviations. Quintessence models are, therefore, in excellent agreement with current data when an interaction is considered. On the other hand, in phantom coupled dark energy models, there is no such preference for a nonzero dark sector coupling. All the models we consider significantly raise the value of the Hubble constant, easing the H-0 tension. In the interacting scenario, the disagreement between Planck thorn BAO and R19 is considerably reduced from 4.3 sigma in the case of the Lambda cold dark matter (Lambda CDM) model to about 2.5 sigma. The addition of low-redshift BAO and SNeIa measurements leaves, therefore, some residual tension with R19 but at a level that could be justified by a statistical fluctuation. Bayesian evidence considerations mildly disfavor both the coupled quintessence and phantom models, while mildly favoring a coupled vacuum scenario, even when late-time datasets are considered. We conclude that nonminimal dark energy cosmologies, such as coupled quintessence, phantom, or vacuum models, are still an interesting route toward softening existing cosmological tensions, even when low-redshift datasets and Bayesian evidence considerations are taken into account.
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