|
|
Chen, P., Centelles Chulia, S., Ding, G. J., Srivastava, R., & Valle, J. W. F. (2019). CP symmetries as guiding posts: Revamping tribimaximal mixing. II. Phys. Rev. D, 100(5), 053001–15pp.
Abstract: In this follow up of arXiv:1812.04663 we analyze the generalized CP symmetries of the charged lepton mass matrix compatible with the complex version of the tribimaximal (TBM) lepton mixing pattern. These symmetries are used to “revamp” the simplest TBM Ansatz in a systematic way. Our generalized patterns share some of the attractive features of the original TBM matrix and are consistent with current oscillation experiments. We also discuss their phenomenological implications both for upcoming neutrino oscillation and neutrinoless double beta decay experiments.
|
|
|
|
Chen, P., Centelles Chulia, S., Ding, G. J., Srivastava, R., & Valle, J. W. F. (2018). Neutrino predictions from generalized CP symmetries of charged leptons. J. High Energy Phys., 07(7), 077–26pp.
Abstract: We study the implications of generalized CP transformations acting on the mass matrices of charged leptons in a model-independent way. Generalized e – mu, e – tau and μ- tau symmetries are considered in detail. In all cases the physical parameters of the lepton mixing matrix, three mixing angles and three CP phases can be expressed in terms of a restricted set of independent “theory parameters” that characterize a given choice of CP transformation. This leads to implications for neutrino oscillations as well as neutrinoless double beta decay experiments.
|
|
|
|
Chen, P., Centelles Chulia, S., Ding, G. J., Srivastava, R., & Valle, J. W. F. (2018). Realistic tribimaximal neutrino mixing. Phys. Rev. D, 98(5), 055019–6pp.
Abstract: We propose a generalized version of the tribimaximal (TBM) ansatz for lepton mixing, leading to a nonzero reactor angle theta(13) and CP violation. The latter is characterized by two CP phases. The Dirac phase, affecting neutrino oscillations, is nearly maximal (delta(CP) similar to +/- pi/2), while the Majorana phase implies narrow allowed ranges for the neutrinoless double beta decay amplitude. The solar angle theta(12) lies nearly at its TBM value, while the atmospheric angle theta(23) has the TBM value for a maximal delta(CP). Neutrino oscillation predictions can be tested in present and upcoming experiments.
|
|
|
|
Chen, P., Ding, G. J., Srivastava, R., & Valle, J. W. F. (2019). Predicting neutrino oscillations with “bi-large” lepton mixing matrices. Phys. Lett. B, 792, 461–464.
Abstract: We propose two schemes for the lepton mixing matrix U = (U1U nu)-U-dagger, where U = U-1 refers to the charged sector, and U-v denotes the neutrino diagonalization matrix. We assume U-nu to be CP conserving and its three angles to be connected with the Cabibbo angle in a simple manner. CP violation arises solely from the U-1, assumed to have the CKM form, U-1 similar or equal to V-CKM, suggested by unification. Oscillation parameters depend on a single parameter, leading to narrow ranges for the “solar” and “accelerator” angles theta(12) and theta(23), as well as for the CP phase, predicted as delta(CP) similar to +/- 1.3 pi.
|
|
|
|
De Romeri, V., Majumdar, A., Papoulias, D. K., & Srivastava, R. (2024). XENONnT and LUX-ZEPLIN constraints on DSNB-boosted dark matter. J. Cosmol. Astropart. Phys., 03(3), 028–34pp.
Abstract: We consider a scenario in which dark matter particles are accelerated to semirelativistic velocities through their scattering with the Diffuse Supernova Neutrino Background. Such a subdominant, but more energetic dark matter component can be then detected via its scattering on the electrons and nucleons inside direct detection experiments. This opens up the possibility to probe the sub -GeV mass range, a region of parameter space that is usually not accessible at such facilities. We analyze current data from the XENONnT and LUX-ZEPLIN experiments and we obtain novel constraints on the scattering cross sections of sub -GeV boosted dark matter with both nucleons and electrons. We also highlight the importance of carefully taking into account Earth's attenuation effects as well as the finite nuclear size into the analysis. By comparing our results to other existing constraints, we show that these effects lead to improved and more robust constraints.
|
|
