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1. Measurement of the e+e− → $$ {B}_s^0{\overline{B}}_s^0X $$ cross section in the energy range from 10.63 to 11.02 GeV using inclusive $$ {D}_s^{+} $$ and D0 production

   https://doi.org/10.1007/JHEP08(2023)131  

   Zhukova, V; Mizuk, R; Adachi, I; Aihara, H; Al_Said, S; Asner, D M; Atmacan, H; Aulchenko, V; Aushev, T; Ayad, R; et al (August 2023, Journal of High Energy Physics)

   A<sc>bstract</sc> We report the first measurement of the inclusivee⁺e⁻→$$ b\overline{b} $$ $b\overline{b}$→$$ {D}_s^{\pm } $$ $D_s^{\pm }$Xande⁺e⁻→$$ b\overline{b} $$ $b\overline{b}$→ D⁰/$$ {\overline{D}}^0 $$ ${\overline{D}}^0$Xcross sections in the energy range from 10.63 to 11.02 GeV. Based on these results, we determineσ(e⁺e⁻→$$ {B}_s^0{\overline{B}}_s^0 $$ $B_s^0{\overline{B}}_s^0$X) andσ(e⁺e⁻→$$ B\overline{B} $$ $B\overline{B}$X) in the same energy range. We measure the fraction of$$ {B}_s^0 $$ $B_s^0$events at Υ(10860) to bef_s= ($$ {22.0}_{-2.1}^{+2.0} $$ ${22.0}_{-2.1}^{+2.0}$)%. We determine also the ratio of the$$ {B}_s^0 $$ $B_s^0$inclusive branching fractions$$ \mathcal{B} $$ $B$($$ {B}_s^0 $$ $B_s^0$→ D⁰/$$ {\overline{D}}^0 $$ ${\overline{D}}^0$X)/$$ \mathcal{B} $$ $B$($$ {B}_s^0 $$ $B_s^0$→$$ {D}_s^{\pm } $$ $D_s^{\pm }$X) = 0.416 ± 0.018 ± 0.092. The results are obtained using the data collected with the Belle detector at the KEKB asymmetric-energye⁺e⁻collider. 

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2. Measurement of CP asymmetry in $$ {\textrm{B}}_{\textrm{s}}^0\to {\textrm{D}}_{\textrm{s}}^{\mp }{\textrm{K}}^{\pm } $$ decays

   https://doi.org/10.1007/JHEP03(2025)139  

   Aaij, R; Abdelmotteleb, A_S W; Abellan_Beteta, C; Abudinén, F; Ackernley, T; Adefisoye, A A; Adeva, B; Adinolfi, M; Adlarson, P; Agapopoulou, C; et al (March 2025, Journal of High Energy Physics)

   A<sc>bstract</sc> A measurement of theCP-violating parameters in$$ {B}_s^0\boldsymbol{\to}{D}_s^{\mp }{K}^{\pm} $$ $B_s^0\to D_s^{\mp }{K}^{\pm }$decays is reported, based on the analysis of proton-proton collision data collected by the LHCb experiment corresponding to an integrated luminosity of 6 fb⁻¹at a centre-of-mass energy of 13 TeV. The measured parameters are obtained with a decay-time dependent analysis yieldingC_f= 0.791 ± 0.061 ± 0.022,$$ {A}_f^{\Delta \Gamma} $$ $A_f^{\text{∆}\Gamma }$= −0.051 ± 0.134 ± 0.058,$$ {A}_{\overline{f}}^{\Delta \Gamma} $$ $A_{\overline{f}}^{\text{∆}\Gamma }$= −0.303 ± 0.125 ± 0.055,S_f= −0.571 ± 0.084 ± 0.023 and$$ {S}_{\overline{f}} $$ $S_{\overline{f}}$= −0.503 ± 0.084 ± 0.025, where the first uncertainty is statistical and the second systematic. This corresponds to CP violation in the interference between mixing and decay of about 8.6σ. Together with the value of the$$ {B}_s^0 $$ $B_s^0$mixing phase −2β_s, these parameters are used to obtain a measurement of the CKM angleγequal to (74 ± 12)° modulo 180°, where the uncertainty contains both statistical and systematic contributions. This result is combined with the previous LHCb measurement in this channel using 3 fb⁻¹resulting in a determination of$$ \gamma ={\left({81}_{-11}^{+12}\right)}^{\circ } $$ $\gamma ={\left({81}_{-11}^{+12}\right)}^{\circ }$. 

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3. Strong-lensing Analysis of SPT-CL J2325−4111 and SPT-CL J0049−2440, Two Powerful Cosmic Telescopes ( R _E > 40″) from the SPT Clusters Sample

   https://doi.org/10.3847/1538-4357/ad9aa5  

   Mahler, Guillaume; Sharon, Keren; Bayliss, Matthew; Bleem, Lindsey E; Brodwin, Mark; Floyd, Benjamin; Gassis, Raven; Gladders, Michael D; Khullar, Gourav; Remolina_González, Juan D; et al (February 2025, The Astrophysical Journal)

   Abstract We report the results from a study of two massive (M_500c> 6.0 × 10¹⁴M_⊙) strong-lensing clusters selected from the South Pole Telescope cluster survey for their large Einstein radius (R_E> 40″), SPT-CL J2325−4111 and SPT-CL J0049−2440. Ground-based and shallow Hubble Space Telescope (HST) imaging indicated extensive strong-lensing evidence in these fields, with giant arcs spanning 18″ and 31″, respectively, motivating further space-based imaging follow-up. Here, we present multiband HST imaging and ground-based Magellan spectroscopy of the fields, from which we compile detailed strong-lensing models. The lens models of SPT-CL J2325−4111 and SPT-CL J0049−2440 were optimized using nine and eight secure multiply imaged systems with a final image-plane rms of 0 $\stackrel{″}{.}$63 and 0 $\stackrel{″}{.}$73, respectively. From the lensing analysis, we measure a projected mass density within 500 kpc ofM(<500 kpc) = (7.30 ± 0.07) × 10¹⁴M_⊙and $M(<500\mathrm{kpc})=7.12_{-0.19}^{+0.16}\times 10^{14}$M_⊙for these two clusters, and subhalo mass ratios of 0.12 ± 0.01 and $0.21_{-0.05}^{+0.07}$, respectively. Both clusters produce a large area with high magnification (μ≥ 3) for a source atz= 9, ${\mathcal{A}}_{\left|\mu \right|\ge 3}^{\mathrm{lens}}=4.93_{-0.04}^{+0.03}$arcmin²and ${\mathcal{A}}_{\left|\mu \right|\ge 3}^{\mathrm{lens}}=3.64_{-0.10}^{+0.14}$arcmin², respectively, placing them in the top tier of strong-lensing clusters. We conclude that these clusters are spectacular sightlines for further observations that will reduce the systematic uncertainties due to cosmic variance. This paper provides the community with two additional well-calibrated cosmic telescopes, as strong as the Frontier Fields and suitable for studies of the highly magnified background Universe. 

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4. Charm production and fragmentation fractions at midrapidity in pp collisions at $$ \sqrt{\textrm{s}} $$ = 13 TeV

   https://doi.org/10.1007/JHEP12(2023)086  

   Acharya, S; Adamová, D; Aglieri_Rinella, G; Agnello, M; Agrawal, N; Ahammed, Z; Ahmad, S; Ahn, S U; Ahuja, I; Akindinov, A; et al (December 2023, Journal of High Energy Physics)

   A<sc>bstract</sc> Measurements of the production cross sections of prompt D⁰, D⁺, D^*+,$$ {\textrm{D}}_{\textrm{s}}^{+} $$ $D_s^{+}$,$$ {\Lambda}_{\textrm{c}}^{+} $$ ${\Lambda }_c^{+}$, and$$ {\Xi}_{\textrm{c}}^{+} $$ ${\Xi }_c^{+}$charm hadrons at midrapidity in proton-proton collisions at$$ \sqrt{s} $$ $\sqrt{s}$= 13 TeV with the ALICE detector are presented. The D-meson cross sections as a function of transverse momentum (p_T) are provided with improved precision and granularity. The ratios ofp_T-differential meson production cross sections based on this publication and on measurements at different rapidity and collision energy provide a constraint on gluon parton distribution functions at low values of Bjorken-x(10⁻⁵–10⁻⁴). The measurements of$$ {\Lambda}_{\textrm{c}}^{+} $$ ${\Lambda }_c^{+}$($$ {\Xi}_{\textrm{c}}^{+} $$ ${\Xi }_c^{+}$) baryon production extend the measuredp_Tintervals down top_T= 0(3) GeV/c. These measurements are used to determine the charm-quark fragmentation fractions and the$$ \textrm{c}\overline{\textrm{c}} $$ $c\overline{c}$production cross section at midrapidity (|y|<0.5) based on the sum of the cross sections of the weakly-decaying ground-state charm hadrons D⁰, D⁺,$$ {\textrm{D}}_{\textrm{s}}^{+} $$ $D_s^{+}$,$$ {\Lambda}_{\textrm{c}}^{+} $$ ${\Lambda }_c^{+}$,$$ {\Xi}_{\textrm{c}}^0 $$ ${\Xi }_c^0$and, for the first time,$$ {\Xi}_{\textrm{c}}^{+} $$ ${\Xi }_c^{+}$, and of the strongly-decaying J/ψmesons. The first measurements of$$ {\Xi}_{\textrm{c}}^{+} $$ ${\Xi }_c^{+}$and$$ {\Sigma}_{\textrm{c}}^{0,++} $$ ${\Sigma }_c^{0,++}$fragmentation fractions at midrapidity are also reported. A significantly larger fraction of charm quarks hadronising to baryons is found compared to e⁺e⁻and ep collisions. The$$ \textrm{c}\overline{\textrm{c}} $$ $c\overline{c}$production cross section at midrapidity is found to be at the upper bound of state-of-the-art perturbative QCD calculations. 

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5. Measurement of the branching fractions of $$ \overline{B} $$ → D(*)K−$$ {K}_{(S)}^{\left(\ast \right)0} $$ and $$ \overline{B} $$ → D(*)$$ {D}_s^{-} $$ decays at Belle II

   https://doi.org/10.1007/JHEP08(2024)206  

   Adachi, I; Aggarwal, L; Aihara, H; Akopov, N; Aloisio, A; Althubiti, N; Anh_Ky, N; Asner, D M; Atmacan, H; Aushev, T; et al (August 2024, Journal of High Energy Physics)

   Abstract We present measurements of the branching fractions of eight$$ {\overline{B}}^0 $$ ${\overline{B}}^0$→D^(*)+K⁻$$ {K}_{(S)}^{\left(\ast \right)0} $$ $K_{\left(S\right)}^{\left(\ast \right)0}$,B⁻→D^(*)0K⁻$$ {K}_{(S)}^{\left(\ast \right)0} $$ $K_{\left(S\right)}^{\left(\ast \right)0}$decay channels. The results are based on data from SuperKEKB electron-positron collisions at the Υ(4S) resonance collected with the Belle II detector, corresponding to an integrated luminosity of 362 fb⁻¹. The event yields are extracted from fits to the distributions of the difference between expected and observedBmeson energy, and are efficiency-corrected as a function ofm(K⁻$$ {K}_{(S)}^{\left(\ast \right)0} $$ $K_{\left(S\right)}^{\left(\ast \right)0}$) andm(D^(*)$$ {K}_{(S)}^{\left(\ast \right)0} $$ $K_{\left(S\right)}^{\left(\ast \right)0}$) in order to avoid dependence on the decay model. These results include the first observation of$$ {\overline{B}}^0 $$ ${\overline{B}}^0$→D⁺K⁻$$ {K}_S^0 $$ $K_S^0$,B⁻→D*⁰K⁻$$ {K}_S^0 $$ $K_S^0$, and$$ {\overline{B}}^0 $$ ${\overline{B}}^0$→D*⁺K⁻$$ {K}_S^0 $$ $K_S^0$decays and a significant improvement in the precision of the other channels compared to previous measurements. The helicity-angle distributions and the invariant mass distributions of theK⁻$$ {K}_{(S)}^{\left(\ast \right)0} $$ $K_{\left(S\right)}^{\left(\ast \right)0}$systems are compatible with quasi-two-body decays via a resonant transition with spin-parityJ^P= 1⁻for theK⁻$$ {K}_S^0 $$ $K_S^0$systems andJ^P= 1⁺for theK⁻K*⁰systems. We also present measurements of the branching fractions of four$$ {\overline{B}}^0 $$ ${\overline{B}}^0$→D^(*)+$$ {D}_s^{-} $$ $D_s^{-}$,B⁻→D^(*)0$$ {D}_s^{-} $$ $D_s^{-}$decay channels with a precision compatible to the current world averages. 

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