The recently proposed PRFG3 method is extended in order to synthesise an atmospheric boundary layer flow, which can be used as inflow condition for Large Eddy Simulation (LES). Firstly, PRFG3 is used ...for generating homogeneous isotropic and homogeneous anisotropic turbulence fields. Based on the obtained results, the method is applied to generate an atmospheric boundary layer, which is used as inflow condition for a LES of a uniform rough terrain, specified in agreement with the Eurocode. Results are discussed based on the analysis of one and two points statistics of the flow field. Good agreement between the target values used in the inflow generation, the synthetic field and the LES, highlights the soundness of the proposed approach. A PRFG3 implementation is available for download at https://site.unibo.it/cwe-lamc/en.
•The recently proposed PRFG3 method is extended in order to synthesise an atmospheric boundary layer flow.•An Eurocode category III velocity profile is generated and applied as inflow condition of a LES.•The resulting flow field is characterized in terms of turbulence intensities and all nine integral length scales.•The obtained flow field well complies with the target values without need of a posteriori calibration.
We report a study of B→(J/ψγ)K and B→(ψ'γ)K decay modes using 772×10⁶ B ̅B events collected at the Υ(4S) resonance with the Belle detector at the KEKB energy-asymmetric e(+)e(-) collider. We observe ...X(3872)→J/ψγ and report the first evidence for χ(c2)→J/ψγ in B→(X_{c ̅cγ)K decays, while in a search for X(3872)→ψ'γ no significant signal is found. We measure the branching fractions, B(B(±)→X(3872)K(±))B(X(3872)→J/ψγ)=(1.78(-0.44)(+0.48)±0.12)×10(-6), B(B(±)→χ(c2)K(±))=(1.11(-0.34)(+0.36)±0.09)×10(-5), B(B(±)→X(3872)K(±))B(X(3872)→ψ'γ)<3.45×10⁶ (upper limit at 90% C.L.), and also provide upper limits for other searches.
We study B --> K(*)l+l- decays (l = e, mu) based on a data sample of 657 x 10(6) BB pairs collected with the Belle detector at the KEKB e+e- collider. We report the differential branching fraction, ...isospin asymmetry, K* polarization, and the forward-backward asymmetry (A(FB)) as functions of q2 = M(ll)(2)c2. The fitted A(FB) spectrum exceeds the standard model expectation by 2.7 standard deviations. The measured branching fractions are B(B --> K*l+l-) = (10.7(-1.0)(+1.1) +/- 0.9) x 10(-7) and B(B --> Kl+l-) = (4.8(-0.4)(+0.5) +/- 0.3) x 10(-7), where the first errors are statistical and the second are systematic, with the muon to electron ratios R(K*) = 0.83 +/- 0.17 +/- 0.08 and R(K) = 1.03 +/- 0.19 +/- 0.06.
We report the results of a high-statistics search for H dibaryon production in inclusive Υ(1S) and Υ(2S) decays. No indication of an H dibaryon with a mass near the M(H)=2m(Λ) threshold is seen in ...either the H→Λpπ(-) or ΛΛ decay channels and 90% confidence level branching-fraction upper limits are set that are between one and two orders of magnitude below the measured branching fractions for inclusive Υ(1S) and Υ(2S) decays to antideuterons. Since Υ(1S,2S) decays produce flavor-SU(3)-symmetric final states, these results put stringent constraints on H dibaryon properties. The results are based on analyses of 102 million Υ(1S) and 158 million Υ(2S) events collected with the Belle detector at the KEKB e(+)e(-) collider.
Abstract
The Cherenkov Telescope Array Observatory (CTAO), currently under construction, is the next-generation very-high-energy gamma-ray observatory, providing the coverage for photons in the ...energy range 20GeV to 300TeV. CTAO will increase detection sensitivity in the 100 GeV to 10TeV range by a factor of 5 — 10 with respect to present experiments. CTAO retrieves the properties of very-high-energy gamma-rays by measuring Cherenkov light emitted by atmospheric showers of secondary particles that incident gamma rays produce in upper layers of the atmosphere. The key for reaching the required energy measurement accuracy is a precise knowledge of the atmospheric transmittance for Cherenkov light, which can be obtained using a dedicated Raman LIDAR. The device should operate at 355nm (near the maximum of Cherenkov light spectrum) and have the capability of taking data at specific azimuth and zenith angles up to distances of 30 km, so that atmospheric transmission along all possible air-shower directions can be determined. The
Barcelona Raman LIDAR
(BRL) is the official CTAO Pathfinder prototype, developed for atmospheric characterization of the Northern CTAO Site at the Observatorio del Roque de los Muchachos (ORM) on the Canary island of La Palma. BRL was deployed at ORM for extensive on-field tests between February 2021 and May 2022. We report on the commissioning results, including the remote operation capabilities of the system and its contribution to the understanding of atmospheric phenomena during its deployment period. In particular, we report on the properties of the volcanic plume from the eruption of the Cumbre Vieja volcano on 22 September 2021.
The cross section for e+ e- --> pi+ pi- psi(2S) between threshold and sqrts=5.5 GeV is measured using 673 fb(-1) of data on and off the Upsilon(4S) resonance collected with the Belle detector at ...KEKB. Two resonant structures are observed in the pi+ pi- psi(2S) invariant-mass distribution, one at 4361 +/- 9 +/- 9 MeV/c2 with a width of 74 +/- 15 +/- 10 MeV/c2, and another at 4664 +/- 11 +/- 5 MeV/c2 with a width of 48 +/- 15 +/- 3 MeV/c2, if the mass spectrum is parametrized with the coherent sum of two Breit-Wigner functions. These values do not match those of any of the known charmonium states.
The lifetime of the τ lepton is measured using the process e+ e- → τ+ τ- , where both τ leptons decay to 3πν(τ). The result for the mean lifetime, based on 711 fb(-1) of data collected with the ...Belle detector at the ϒ(4S) resonance and 60 MeV below, is τ=(290.17±0.53(stat)±0.33(syst))×10(-15) s. The first measurement of the lifetime difference between τ+ and τ- is performed. The upper limit on the relative lifetime difference between positive and negative τ leptons is |Δτ|/τ<7.0×10(-3) at 90% C.L.
We present results from a study of X(3872)→ππJ/ψ decays produced via exclusive B→KX(3872) decays. We determine the mass to be MX(3872)=(3871.85±0.27(stat)±0.19(syst)) MeV, a 90% confidence level ...upper limit on the natural width of ΓX(3872)<1.2 MeV, the product branching fraction B(B+→K+X(3872))×B(X(3872)→π+π-J/ψ)=(8.63±0.82(stat)±0.52(syst))×10-6, and a ratio of branching fractions B(B0→K0X(3872))/B(B+→K+X(3872))=0.50±0.14(stat)±0.04(syst). The difference in mass between the X(3872)→π+π-J/ψ signals in B+ and B0 decays is ΔMX(3872)=(-0.71±0.96(stat)±0.19(syst)) MeV. A search for a charged partner of the X(3872) in the decays B0→K-X+ or B+→K0X+, X+→π+π0J/ψ resulted in upper limits on the product branching fractions for these processes that are well below expectations for the case that the X(3872) is the neutral member of an isospin triplet. In addition, we examine possible JPC quantum number assignments for the X(3872) based on comparisons of angular correlations between final state particles in X(3872)→π+π-J/ψ decays with simulated data for JPC values of 1++ and 2-+. We examine the influence of ρ-ω interference in the M(π+π-) spectrum. The analysis is based on a 711 fb-1 data sample that contains 772×106 BB meson pairs collected at the Υ(4S) resonance in the Belle detector at the KEKB e+e- collider.
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