Molina, R., Liang, W. H., Xiao, C. W., Sun, Z. F., & Oset, E. (2024). Two states for the Ξ(1820) resonance. Phys. Lett. B, 856, 138872–4pp.
Abstract: We recall that the chiral unitary approach for the interaction of pseudoscalar mesons with the baryons of the decuplet predicts two states for the Xi(1820) resonance, one with a narrow width and the other one with a large width. We contrast this fact with the recent BESIII measurement of the K- Lambda mass distribution in the psi(3686) decay to K- Lambda Xi(+), which demands a width much larger than the average of the PDG, and show how the consideration of the two Xi(1820) states provides a natural explanation to the experimental data.
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Abreu, L. M., Dai, L. R., & Oset, E. (2023). J/Psi decay to omega, phi, K*0 plus f0(1370), f0(1710), K0*(1430), f2(1270), f'2 (1525) and K2*(1430): Role of the D-wave for tensor production. Phys. Lett. B, 843, 137999–10pp.
Abstract: We reassess the decay of the J/Psi into an omega, phi, K*0 and one of the f0(1370), f0(1710), f2(1270), f'2 (1525), K0*(1430) and K2*(1430) resonances. We benefit from previous works that considered this reaction as a J/Psi decay into three vector mesons, with a scalar or tensor resonance being formed from the interaction of two of these vectors. The novelty here with respect to former studies is the investigation of the relation between the scalar meson and tensor productions for the first time. To this end, the spin structure of the four vectors present in the production vertex is analyzed, and the D-wave mechanism in the tensor production is included. Then, beyond the ratios studied previously involving scalar states and tensor states independently, new ratios relating the scalar and tensor meson productions are estimated. Our results suggest that the D-wave mechanism of tensor production assumes a relevant contribution. New experimental data reporting the angular distributions of these processes will be important for checking this conclusion.
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Shi, P. P., Albaladejo, M., Du, M. L., Guo, F. K., & Nieves, J. (2025). P-wave charmonium contribution to hidden-charm states from a reanalysis of lattice QCD data. Phys. Rev. D, 111(7), 074043–26pp.
Abstract: We reanalyze, considering the contribution of P-wave charmonia, lattice data for the DD<overline>-DSD<overline>S coupled-channel of Prelovsek et al. [J. High Energy Phys. 06 (2021) 035.] and DD<overline>* systems of Prelovsek et al. [Phys. Rev. Lett. 111, 192001 (2013).] with m pi <^> 280 and 266 MeV, and L = 24a/32a (a <^> 0.09 fm) and L = 16a (a <^> 0.1239(13) fm), respectively. The hidden-charm states with JPC = 0++, 1++, and 2++ quantum numbers are then searched for. For 0++, the analysis reveals three poles in the DD<overline>-DSD<overline>S coupled-channel amplitude, corresponding to three states. Two of these poles, located near the DD<overline> and DSD<overline>S thresholds, can be interpreted as mostly molecular states. A third pole above the DSD<overline>S threshold is originated from the P-wave chi c0(2P) charmonium state. The number of poles found in the DD<overline>-DSD<overline>S system is the same as that found in the original lattice analysis though the position of the third pole changes sizeably. In the 1++ sector, we find two poles in the complex energy plane. The first one is related to the molecular X(3872) state, with a compositeness exceeding 90%, while the second one, stemming from the chi c1(2P) charmonium, appears above the DD<overline>* threshold and it likely corresponds to the recently discovered chi c1(4010) state. In the 2++ sector, we also report two poles and find that the dressed chi c2(2P) is lighter than the D*D<overline>* molecular state, with the dynamics of the latter closely related to that of the heavy-quark spin-symmetry partner of the X(3872). Our exploratory study of the 1++ and 2++ sectors offers valuable insights into their dynamics, but given that the fits that we carry out are underconstrained, more lattice data are required to draw robust conclusions.
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IceCube Collaboration(Abbasi, R. et al), & Garcia, A. (2024). Methods and stability tests associated with the sterile neutrino search using improved high-energy νμ event reconstruction in IceCube. Phys. Rev. D, 110(9), 092009–19pp.
Abstract: We provide supporting details for the search for a 3 +1 sterile neutrino using data collected over 10.7 years at the IceCube Neutrino Observatory. The analysis uses atmospheric muon-flavored neutrinos from 0.5 to 100 TeV that traverse Earth to reach the IceCube detector and finds a best-fit point at sin(2)(2 theta(24)) = 0.16 and Delta m(41)(2) = 3.5 eV(2) with a goodness-of-fit p value of 12% and consistency with the null hypothesis of no oscillations to sterile neutrinos with a p value of 3.1%. Several improvements were made over past analyses, which are reviewed in this article, including upgrades to the reconstruction and the study of sources of systematic uncertainty. We provide details of the fit quality and discuss stability tests that split the data for separate samples, comparing results. We find that the fits are consistent between split datasets.
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Bazzocchi, F., Cerdeño, D. G., Muñoz, C., & Valle, J. W. F. (2010). Calculable inverse-seesaw neutrino masses in supersymmetry. Phys. Rev. D, 81(5), 051701–5pp.
Abstract: We provide a scenario where naturally small and calculable neutrino masses arise from a supersymmetry-breaking renormalization-group-induced vacuum expectation value. The construction consists of an extended version of the next-to-minimal supersymmetric standard model and the mechanism is illustrated for a universal choice of the soft supersymmetry-breaking parameters. The lightest supersymmetric particle can be an isosinglet scalar neutrino state, potentially viable as WIMP dark matter through its Higgs new boson coupling. The scenario leads to a plethora of new phenomenological implications at accelerators including the Large Hadron Collider.
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Husek, T., Goudzovski, E., & Icampf, K. (2019). Precise Determination of the Branching Ratio of the Neutral-Pion Dalitz Decay. Phys. Rev. Lett., 122(2), 022003–6pp.
Abstract: We provide a new value for the ratio R = Gamma(pi(0) -> e(+)e(-)gamma(gamma))/Gamma(pi(0) -> gamma gamma) = 11.978(6) x 10(-3), which is by 2 orders of magnitude more precise than the current Particle Data Group average. It is obtained using the complete set of the next-to-leading-order radiative corrections in the QED sector, and incorporates up-to-date values of the pi(0)-transition-form-factor slope. The ratio R translates into the branching ratios of the two main pi(0) decay modes: B(pi(0) -> gamma gamma) = 98.8131(6)% and B(pi(0) -> e(+)e(-)gamma(gamma)) = 1.1836(6)%.
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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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Centelles Chulia, S., Herrero-Brocal, A., & Vicente, A. (2024). The Type-I Seesaw family. J. High Energy Phys., 07(7), 060–35pp.
Abstract: We provide a comprehensive analysis of the Type-I Seesaw family of neutrino mass models, including the conventional type-I seesaw and its low-scale variants, namely the linear and inverse seesaws. We establish that all these models essentially correspond to a particular form of the type-I seesaw in the context of explicit lepton number violation. We then focus into the more interesting scenario of spontaneous lepton number violation, systematically categorizing all inequivalent minimal models. Furthermore, we identify and flesh out specific models that feature a rich majoron phenomenology and discuss some scenarios which, despite having heavy mediators and being invisible in processes such as μ-> e gamma, predict sizable rates for decays including the majoron in the final state.
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Centelles Chulia, S., Cepedello, R., Peinado, E., & Srivastava, R. (2019). Systematic classification of two-loop d=4 Dirac neutrino mass models and the Diracness-dark matter stability connection. J. High Energy Phys., 10(10), 093–33pp.
Abstract: We provide a complete systematic classification of all two-loop realizations of the dimension four operator for Dirac neutrino masses. Our classification is multi-layered, starting first with a classification in terms of all possible distinct two loop topologies. Then we discuss the possible diagrams for each topology. Model-diagrams originating from each diagram are then considered. The criterion for genuineness is also defined and discussed at length. Finally, as examples, we construct two explicit models which also serve to highlight the intimate connection between the Dirac nature of neutrinos and the stability of dark matter.
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Motohashi, H., & Hu, W. (2017). Generalized slow roll in the unified effective field theory of inflation. Phys. Rev. D, 96(2), 023502–17pp.
Abstract: We provide a compact and unified treatment of power spectrum observables for the effective field theory (EFT) of inflation with the complete set of operators that lead to second-order equations of motion in metric perturbations in both space and time derivatives, including Horndeski and Gleyzes-Langlois-Piazza-Vernizzi theories. We relate the EFT operators in ADM form to the four additional free functions of time in the scalar and tensor equations. Using the generalized slow-roll formalism, we show that each power spectrum can be described by an integral over a single source that is a function of its respective sound horizon. With this correspondence, existing model independent constraints on the source function can be simply reinterpreted in the more general inflationary context. By expanding these sources around an optimized freeze-out epoch, we also provide characterizations of these spectra in terms of five slow-roll hierarchies whose leading-order forms are compact and accurate as long as EFT coefficients vary only on time scales greater than an e-fold. We also clarify the relationship between the unitary gauge observables employed in the EFT and the comoving gauge observables of the postinflationary universe.
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