Roca, L., Song, J., & Oset, E. (2024). Molecular pentaquarks with hidden charm and double strangeness. Phys. Rev. D, 109(9), 094005–8pp.
Abstract: We analyze theoretically the coupled-channel meson-baryon interaction with global flavor c<overline>cssn and c<overline>csss, where mesons are pseudoscalars or vectors, and baryons have JP = 1/2+ or 3/2+. The aim is to explore whether the nonlinear dynamics inherent in the unitarization process within coupled channels can dynamically generate double- and triple-strange pentaquark-type states (Pcss and Pcsss, respectively), for which there is no experimental evidence to date. We evaluate the s-wave scattering matrix by implementing unitarity in coupled channels, using potential kernels obtained from t-channel vector meson exchange. The required PPV and VVV vertices are obtained from Lagrangians derived through appropriate extensions of the local hidden gauge symmetry approach to the charm sector, while capitalizing on the symmetry of the spin and flavor wave function to evaluate the BBV vertex. We find four different poles in the double strange sector, some of them degenerate in spin. For the triple-strange channel, we find the meson-baryon interaction insufficient to generate a bound or resonance state through the unitary coupled-channel dynamics.
|
Centelles Chulia, S., Miranda, O. G., & Valle, J. W. F. (2024). Leptonic neutral-current probes in a short-distance DUNE-like setup. Phys. Rev. D, 109(11), 115007–12pp.
Abstract: Precision measurements of neutrino -electron scattering may provide a viable way to test the nonminimal form of the charged and neutral current weak interactions within a hypothetical near -detector setup for the Deep Underground Neutrino Experiment (DUNE). Although low -statistics, these processes are clean and provide information complementing the results derived from oscillation studies. They could shed light on the scale of neutrino mass generation in low -scale seesaw schemes.
|
Rossi, R. R., Sanchez Garcia, G., & Tortola, M. (2024). Probing nuclear properties and neutrino physics with current and future CEνNS experiments. Phys. Rev. D, 109(9), 095044–17pp.
Abstract: The recent observation of coherent elastic neutrino-nucleus scattering (CEvNS) with neutrinos from pion decay at rest (N-DAR) sources by the COHERENT Collaboration has raised interest in this process in the search for new physics. Unfortunately, current uncertainties in the determination of nuclear parameters relevant to those processes can hide new physics effects. This is not the case for processes involving lower-energy neutrino sources such as nuclear reactors. Note, however, that a CEvNS measurement with reactor neutrinos depends largely on a (still-missing) precise determination of the quenching factor at very low energies, making its observation more challenging. In the upcoming years, once this signal is confirmed, a combined analysis of N-DAR and reactor CEvNS experiments will be very useful to probe particle and nuclear physics, with a reduced dependence on nuclear uncertainties. In this work, we explore this idea by simultaneously testing the sensitivity of current and future CEvNS experiments to neutrino nonstandard interactions (NSIs) and the neutron root mean square (rms) radius, considering different neutrino sources as well as several detection materials. We show how the interplay between future reactor and accelerator CEvNS experiments can help to get robust constraints on the neutron rms and to break degeneracies between the NSI parameters. Our forecast could be used as a guide to optimize the experimental sensitivity to the parameters under study.
|
Servant, G., & Simakachorn, P. (2024). Ultrahigh frequency primordial gravitational waves beyond the kHz: The case of cosmic strings. Phys. Rev. D, 109(10), 103538–24pp.
Abstract: We investigate gravitational -wave backgrounds (GWBs) of primordial origin that would manifest only at ultrahigh frequencies, from kilohertz to 100 gigahertz, and leave no signal at LIGO, the Einstein Telescope, the Cosmic Explorer, LISA, or pulsar -timing arrays. We focus on GWBs produced by cosmic strings and make predictions for the GW spectra scanning over high-energy scale (beyond 10 10 GeV) particle physics parameters. Signals from local string networks can easily be as large as the big bang nucleosynthesis/ cosmic microwave background bounds, with a characteristic strain as high as 10 – 26 in the 10 kHz band, offering prospects to probe grand unification physics in the 10 14 -10 17 GeV energy range. In comparison, GWB from axionic strings is suppressed (with maximal characteristic strain similar to 10 – 31 ) due to the early matter era induced by the associated heavy axions. We estimate the needed reach of hypothetical futuristic GW detectors to probe such GWB and, therefore, the corresponding high-energy physics processes. Beyond the information of the symmetry -breaking scale, the high -frequency spectrum encodes the microscopic structure of the strings through the position of the UV cutoffs associated with cusps and kinks, as well as potential information about friction forces on the string. The IR slope, on the other hand, reflects the physics responsible for the decay of the string network. We discuss possible strategies for reconstructing the scalar potential, particularly the scalar self -coupling, from the measurement of the UV cutoff of the GW spectrum.
|
del Rio, A., & Ester, E. A. (2024). Electrically charged black hole solutions in semiclassical gravity and dynamics of linear perturbations. Phys. Rev. D, 109(10), 105022–23pp.
Abstract: We explore quantum corrections of electrically charged black holes subject to vacuum polarization effects of fermion fields in QED. Solving this problem exactly is challenging so we restrict to perturbative corrections that one can obtain using the heat kernel expansion in the one -loop effective action for electrons. Starting from the corrections originally computed by Drummond and Hathrell, we solve the full semiclassical Einstein -Maxwell system of coupled equations to leading order in Planck 's constant and find a new electrically charged, static black hole solution. To probe these quantum corrections, we study electromagnetic and gravitational (axial) perturbations on this background and derive the coupled system of Regge-Wheeler master equations that govern the propagation of these waves. In the classical limit, our results agree with previous findings in the literature. We finally compare these results with those that one can obtain by working out the Euler-Heisenberg effective action. We find again a new electrically charged static black hole spacetime and derive the coupled system of Regge-Wheeler equations governing the propagation of axial electromagnetic and gravitational perturbations. Results are qualitatively similar in both cases. We briefly discuss some challenges found in the numerical computation of the quasinormal mode frequency spectra when quantum corrections are included.
|
Navarro, P., Gimeno, B., Monzo-Cabrera, J., Diaz-Morcillo, A., & Blas, D. (2024). Study of a cubic cavity resonator for gravitational waves detection in the microwave frequency range. Phys. Rev. D, 109(10), 104048–19pp.
Abstract: The direct detection of gravitational waves (GWs) of frequencies above MHz has recently received considerable attention. In this work, we present a precise study of the reach of a cubic cavity resonator to GWs in the microwave range, using for the first time tools allowing to perform realistic simulations. Concretely, the boundary integral -resonant mode expansion (BI-RME) 3D method, which allows us to obtain not only the detected power but also the detected voltage (magnitude and phase), is used here. After analyzing three cubic cavities for different frequencies and working simultaneously with three different degenerate modes at each cavity, we conclude that the sensitivity of the experiment is strongly dependent on the polarization and incidence angle of the GW. The presented experiment can reach sensitivities up to 1 x 10 – 19 at 100 MHz, 2 x 10 – 20 at 1 GHz, and 6 x 10 – 19 at 10 GHz for optimal angles and polarizations, and where in all cases we assumed an integration time of Delta t 1 / 4 1 ms. These results provide a strong case for further developing the use of cavities to detect GWs. Moreover, the possibility of analyzing the detected voltage (magnitude and phase) opens a new interferometric detection scheme based on the combination of the detected signals from multiple cavities.
|
LHCb Collaboration(Aaij, R. et al), Jaimes Elles, S. J., Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., Rebollo De Miguel, M., et al. (2024). Measurement of Ξc+ production in pPb collisions at √sNN=8.16 TeV at LHCb. Phys. Rev. C, 109(4), 044901–14pp.
Abstract: A study of prompt Xi(+)(c) production in proton-lead collisions is performed with the LHCb experiment at a centerof-mass energy per nucleon pair of 8.16 TeV in 2016 in pPb and Pbp collisions with an estimated integrated luminosity of approximately 12.5 and 17.4 nb(-1), respectively. The Xi(+)(c) roduction cross section, as well as the Xi(+)(c) to Lambda(+)(c) production cross-section ratio, are measured as a function of the transverse momentum and rapidity and compared to the latest theory predictions. The forward-backward asymmetry is also measured as a function of the Xi(+)(c) ransverse momentum. The results provide strong constraints on theoretical calculation and are a unique input for hadronization studies in different collision systems.
|
Domingo, F., Kim, J. S., Martin Lozano, V., Martin-Ramiro, P., & Ruiz de Austri, R. (2020). Confronting the neutralino and chargino sector of the NMSSM with the multilepton searches at the LHC. Phys. Rev. D, 101(7), 075010–29pp.
Abstract: We test the impact of the ATLAS and CMS multilepton searches performed at the LHC with 8 as well as 13 TeV center-of-mass energy (using only the pre-2018 results) on the chargino and neutralino sector of the next-to-minimal supersymmetric Standard Model (NMSSM). Our purpose consists in analyzing the actual reach of these searches for a full model and in emphasizing effects beyond the minimal supersymmetric Standard Model (MSSM) that affect the performance of current (MSSM-inspired) electroweakino searches. To this end, we consider several scenarios characterizing specific features of the NMSSM electroweakino sector. We then perform a detailed collider study, generating Monte Carlo events through PYTHIA and testing against current LHC constraints implemented in the public tool CheckMATE. We find e.g., that supersymmetric decay chains involving intermediate singlino or Higgs-singlet states can modify the naive MSSM-like picture of the constraints by inducing final states with softer or less easily identifiable SM particles-reversely, a compressed configuration with singlino next-to-lightest supersymmetric particle occasionally induces final states that are rich with photons, which could provide complementary search channels.
|
ATLAS Collaboration(Aad, G. et al), Aikot, A., Amos, K. R., Aparisi Pozo, J. A., Bailey, A. J., Bouchhar, N., et al. (2024). Measurement of the production cross-section of J/ψ and ψ(2S) mesons in pp collisions at √s=13 TeV with the ATLAS detector. Eur. Phys. J. C, 84(2), 169–30pp.
Abstract: Measurements of the differential production cross-sections of prompt and non-prompt J/psi and psi(2S) mesons with transverse momenta between 8 and 360 GeV and rapidity in the range vertical bar y vertical bar < 2 are reported. Furthermore, measurements of the non-prompt fractions of J/psi and psi(2S), and the prompt and non-prompt psi(2S)-to-J/psi production ratios, are presented. The analysis is performed using 140 fb(-1) of root s = 13 TeV pp collision data recorded by the ATLAS detector at the LHC during the years 2015-2018.
|
Torres-Sanchez, P., Steiger, H. T. J., Mastinu, P., Wyss, J. L., Kayser, L., Silvestrin, L., et al. (2024). Fast neutron production at the LNL Tandem from the 7Li(14N,xn)X reaction. Eur. Phys. J. C, 84(4), 372–11pp.
Abstract: Fast neutron beams (E-n>1 MeV) are of relevance for many scientific and industrial applications. This paper explores fast neutron production using a TANDEM accelerator at the Legnaro National Laboratories, via an energetic ion beam (90 MeV N-14) onto a lithium target. The high energy models for nuclear collision of FLUKA foresee large neutron yields for reactions of this kind. The experiment aimed at validating the expected neutron yields from FLUKA simulations, using two separate and independent set-ups: one based on the multi-foil activation technique, and the other on the time of flight technique, by using liquid scintillator detectors. The results of the experiment show clear agreement of the measured spectra with the FLUKA simulations, both in the shape and the magnitude of the neutron flux at the mea-sured positions. The neutron spectrum is centered around the 8 MeV range with mild tails, and a maximum neutron energy spanning up to 50 MeV. These advantageous results provide a starting point in the development of fast neutron beams based on high energy ion beams from medium-sized accelerator facilities
|
