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XENON Collaboration(Aprile, E. et al), & Orrigo, S. E. A. (2017). Online Rn-222 removal by cryogenic distillation in the XENON100 experiment. Eur. Phys. J. C, 77(6), 358–8pp.
Abstract: We describe the purification of xenon from traces of the radioactive noble gas radon using a cryogenic distillation column. The distillation column was integrated into the gas purification loop of the XENON100 detector for online radon removal. This enabled us to significantly reduce the constant Rn-222 background originating from radon emanation. After inserting an auxiliary 222Rn emanation source in the gas loop, we determined a radon reduction factor of R > 27 (95% C.L.) for the distillation column by monitoring the Rn-222 activity concentration inside the XENON100 detector.
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Wang, Y. F., Yao, D. L., & Zheng, H. Q. (2018). New insights on low energy pi N scattering amplitudes. Eur. Phys. J. C, 78(7), 543–18pp.
Abstract: The S- and P- wave phase shifts of low-energy pion-nucleon scatterings are analysed using Peking University representation, in which they are decomposed into various terms contributing either from poles or branch cuts. We estimate the left-hand cut contributions with the help of tree-level perturbative amplitudes derived in relativistic baryon chiral perturbation theory up to O(p(2)). It is found that in S-11 and P-11 channels, contributions from known resonances and cuts are far from enough to saturate experimental phase shift data – strongly indicating contributions from low lying poles undiscovered before, and we fully explore possible physics behind. On the other side, no serious disagreements are observed in the other channels.
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Wang, G. Y., Roca, L., Wang, E., Liang, W. H., & Oset, E. (2020). Signatures of the two K1(1270) poles in D – plus ve plus V P decay. Eur. Phys. J. C, 80(5), 388–7pp.
Abstract: We analyze theoretically the D+ ye+ pK and D+ pe+ K*7 decays to see the feasibility to check the double pole nature of the axial -vector resonance Kt(1270) predicted by the unitary extensions of chiral perturbation theory (UChPT). Indeed, within UChPT the K1(1270) is dynamically generated from the interaction of a vector and a pseudoscalar meson, and two poles are obtained for the quantum numbers of this resonance. The lower mass pole couples dominantly to 10 and the higher mass pole to pK, therefore we can expect that different reactions weighing differently these channels in the production mechanisms enhance one or the other pole. We show that the different final V P channels in D pe+ V P weigh differently both poles, and this is reflected in the shape of the final vector-pseudoscalar invariant mass distributions. Therefore, we conclude that these decays are suitable to distinguish experimentally the predicted double pole of the Kt(1270) resonance.
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Wang, D. (2023). Pantheon plus tomography and Hubble tension. Eur. Phys. J. C, 83(9), 813–12pp.
Abstract: The recently released Type Ia supernovae (SNe Ia) sample, Pantheon+, is an updated version of Pantheon and has very important cosmological implications. To explore the origin of the enhanced constraining power and internal correlations of datasets in different redshifts, we perform a comprehensively tomographic analysis of the Pantheon+ sample without and with the Cepheid host distance calibration, respectively. Specifically, we take two binning methods to analyze the Pantheon+ sample, i.e., equal redshift interval and equal supernovae number for each bin. For the case of equal redshift interval, after dividing the sample to 10 bins, the first bin in the redshift range z is an element of [0.00122, 0.227235] dominates the constraining power of the whole sample. For the case of equal supernovae number, the first three low redshift bins prefer a large matter fraction Omega(m) and only the sixth bin gives a relatively low cosmic expansion rate H-0. For both binning methods, we find no obvious evidence of evolution of H-0 and Omega(m) at the 2 sigma confidence level. The inclusion of the SHOES calibration can significantly compress the parameter space of background dynamics of the universe in each bin. When not considering the calibration, combining the Pantheon+ sample with cosmic microwave background, baryon acoustic oscillations, cosmic chronometers, galaxy clustering and weak lensing data, we give the strongest 1 sigma constraint H-0 = 67.88 +/- 0.42kms(-1) Mpc(-1). However, the addition of the calibration leads to a global shift of the parameter space from the combined constraint and H-0 = 68.66 +/- 0.42 km s(-1) Mpc(-1), which is inconsistent with the Planck-2018 result at about 2 sigma confidence level.
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Vento, V., & Traini, M. (2020). Scattering of charged particles off monopole-anti-monopole pairs. Eur. Phys. J. C, 80(1), 62–10pp.
Abstract: The Large Hadron Collider is reaching energies never achieved before allowing the search for exotic particles in the TeV mass range. In a continuing effort to find monopoles we discuss the effect of the magnetic dipole field created by a pair of monopole-anti-monopole or monopolium on the successive bunches of charged particles in the beam at LHC.
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