ATLAS Collaboration(Aad, G. et al), Aparisi Pozo, J. A., Bailey, A. J., Cabrera Urban, S., Cardillo, F., Castillo Gimenez, V., et al. (2022). Search for exotic decays of the Higgs boson into b(b)over-bar and missing transverse momentum in pp collisions at root s=13 TeV with the ATLAS detector. J. High Energy Phys., 01(1), 063–38pp.
Abstract: A search for the exotic decay of the Higgs boson (H) into a b (b) over bar resonance plus missing transverse momentum is described. The search is performed with the ATLAS detector at the Large Hadron Collider using 139 fb(-1) of pp collisions at root s = 13 TeV. The search targets events from ZH production in an NMSSM scenario where H -> chi(similar to 0)(2)chi(similar to 0)(1), with chi(similar to 0)(2) -> a chi(similar to 0)(1), where a is a light pseudoscalar Higgs boson and chi(similar to 0)(1,)(2) are the two lightest neutralinos. The decay of the a boson into a pair of b-quarks results in a peak in the dijet invariant mass distribution. The final-state signature consists of two leptons, two or more jets, at least one of which is identified as originating from a b-quark, and missing transverse momentum. Observations are consistent with Standard Model expectations and upper limits are set on the product of cross section times branching ratio for a three-dimensional scan of the masses of the chi(similar to 0)(2), chi(similar to 0)(1) and a boson.
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LHCb Collaboration(Aaij, R. et al), Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., & Ruiz Vidal, J. (2022). Measurement of chi(c1) (3872) production in proton-proton collisions at root s=8 and 13 TeV. J. High Energy Phys., 01(1), 131–27pp.
Abstract: The production cross-section of the chi(c1)(3872) state relative to the psi(2S) meson is measured using proton-proton collision data collected with the LHCb experiment at centre-of-mass energies of root s = 8 and 13 TeV, corresponding to integrated luminosities of 2.0 and 5.4 fb(-1), respectively. The two mesons are reconstructed in the J/psi pi(+) pi(-) final state. The ratios of the prompt and nonprompt chi(c1)(3872) to psi(2S) production cross-sections are measured as a function of transverse momentum, p(T), and rapidity, y, of the chi(c1)(3872) and psi(2S) states, in the kinematic range 4 < p(T) < 20 GeV/c and 2.0 < y < 4.5. The prompt ratio is found to increase with pT , independently of y. For the prompt component, the double ratio of the chi(c1)(3872) and psi(2S) production cross-sections between 13 and 8 TeV is observed to be consistent with unity, independent of p(T) and centre-of-mass energy.
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LHCb Collaboration(Aaij, R. et al), Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., & Ruiz Vidal, J. (2022). Measurement of prompt charged-particle production in pp collisions at root s=13 TeV. J. High Energy Phys., 01(1), 166–39pp.
Abstract: The differential cross-section of prompt inclusive production of long-lived charged particles in proton-proton collisions is measured using a data sample recorded by the LHCb experiment at a centre-of-mass energy of root s = 13 TeV. The data sample, collected with an unbiased trigger, corresponds to an integrated luminosity of 5.4 nb(-1). The differential cross-section is measured as a function of transverse momentum and pseudorapidity in the ranges P-T is an element of [80, 10 000) MeV/c and eta is an element of [2.0, 4.8) and is determined separately for positively and negatively charged particles. The results are compared with predictions from various hadronic-interaction models.
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LHCb Collaboration(Aaij, R. et al), Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., & Ruiz Vidal, J. (2022). Search for the radiative Xi(-)(b) -> Xi(-)gamma decay. J. High Energy Phys., 01(1), 069–20pp.
Abstract: The first search for the rare radiative decay Xi(-)(b) -> Xi(-)gamma is performed using data collected by the LHCb experiment in proton-proton collisions at a center-of-mass energy of 13TeV, corresponding to an integrated luminosity of 5.4 fb(-1). The Xi(-)(b) -> Xi(-)-J/ psi channel is used as normalization. No Xi(-)(b) -> Xi(-)gamma signal is found and an upper limit of B(Xi(-)(b) -> Xi(-)gamma) < 1.3 x 10(-4) at 95% confidence level is obtained.
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Sierra, D. A., De Romeri, V., Flores, L. J., & Papoulias, D. K. (2022). Impact of COHERENT measurements, cross section uncertainties and new interactions on the neutrino floor. J. Cosmol. Astropart. Phys., 01(1), 055–26pp.
Abstract: We reconsider the discovery limit of multi-ton direct detection dark matter experiments in the light of recent measurements of the coherent elastic neutrino-nucleus scattering process. Assuming the cross section to be a parameter entirely determined by data, rather than using its Standard Model prediction, we use the COHERENT CsI and LAr data sets to determine WIMP discovery limits. Being based on a data-driven approach, the results are thus free from theoretical assumptions and fall within the WIMP mass regions where XENONnT and DARWIN have best expected sensitivities. We further determine the impact of subleading nuclear form factor and weak mixing angle uncertainties effects on WIMP discovery limits. We point out that these effects, albeit small, should be taken into account. Moreover, to quantify the impact of new physics effects in the neutrino background, we revisit WIMP discovery limits assuming light vector and scalar mediators as well as neutrino magnetic moments/transitions. We stress that the presence of new interactions in the neutrino sector, in general, tend to worsen the WIMP discovery limit.
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