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The SHiP-charm project was proposed to measure the associated charm production induced by 400 GeV/c protons in a thick target, including the contribution from cascade production. An optimisation run was performed in July 2018 at CERN SPS using a hybrid setup. The high resolution of nuclear emulsions acting as vertex detector was complemented by electronic detectors for kinematic measurements and muon identification. Here we present first results on the analysis of nuclear emulsions exposed in the 2018 run, which prove the capability of reconstructing proton interaction vertices in a harsh environment, where the signal is largely dominated by secondary particles produced in hadronic and electromagnetic showers within the lead target.

The CMS detector, including its muon system, has been operating at the CERN LHC in increasingly challenging conditions for about 15 years. The muon detector was designed to provide excellent triggering and track reconstruction for muons produced in proton–proton collisons at an instantaneous luminosity ( $$\\mathcal {L}$$ L ) of $$1 \\times 10^{34}$$ 1 × 10 34  cm $$^{-2}$$ - 2 s $$^{-1}$$ - 1 . During the Run 2 data-taking period (2015–2018), the LHC achieved an instantaneous luminosity of twice its design value, resulting in larger background rates and making the efficient detection of muons more difficult. While some backgrounds result from natural radioactivity, cosmic rays, and interactions of the circulating protons with residual gas in the beam pipe, the dominant source of background hits in the muon system arises from proton–proton interactions themselves. Charged hadrons leaving the calorimeters produce energy deposits in the muon chambers. In addition, high-energy particles interacting in the hadron calorimeter and forward shielding elements generate thermal neutrons, which leak out of the calorimeter and shielding structures, filling the CMS cavern. We describe the method used to measure the background rates in the various muon subsystems. These rates, in conjunction with simulations, can be used to estimate the expected backgrounds in the High-Luminosity LHC. This machine will run for at least 10 years starting in 2029 reaching an instantaneous luminosity of $$\\mathcal {L} = 5 \\times \\text {10}^\\text {34}\\,\\text {cm}^\\text {-2}\\,\\text {s}^\\text {-1}$$ L = 5 × 10 34 cm -2 s -1 and increasing ultimately to $$\\mathcal {L} = 7.5 \\times \\text {10}^\\text {34}\\,\\text {cm}^\\text {-2}\\,\\text {s}^\\text {-1}$$ L = 7.5 × 10 34 cm -2 s -1 . These background estimates have been a key ingredient for the planning and design of the muon detector upgrade.

The Compact Muon Solenoid (CMS) experiment prepares its Phase-2 upgrade for the high-luminosity era of the LHC operation (HL-LHC). Due to the increase of occupancy, trigger latency and rates, the full electronics of the CMS Drift Tube (DT) chambers will need to be replaced. In the new design, the time bin for the digitisation of the chamber signals will be of around 1~ns, and the totality of the signals will be forwarded asynchronously to the service cavern at full resolution. The new backend system will be in charge of building the trigger primitives of each chamber. These trigger primitives contain the information at chamber level about the muon candidates position, direction, and collision time, and are used as input in the L1 CMS trigger. The added functionalities will improve the robustness of the system against ageing. An algorithm based on analytical solutions for reconstructing the DT trigger primitives, called Analytical Method, has been implemented both as a software C++ emulator and in firmware. Its performance has been estimated using the software emulator with simulated and real data samples, and through hardware implementation tests. Measured efficiencies are 96 to 98\\% for all qualities and time and spatial resolutions are close to the ultimate performance of the DT chambers. A prototype chain of the HL-LHC electronics using the Analytical Method for trigger primitive generation has been installed during Long Shutdown 2 of the LHC and operated in CMS cosmic data taking campaigns in 2020 and 2021. Results from this validation step, the so-called Slice Test, are presented.

Dark photons are hypothetical massive vector particles that could mix with ordinary photons. The simplest theoretical model is fully characterised by only two parameters: the mass of the dark photon m\\(_{\\gamma^{\\mathrm{D}}}\\) and its mixing parameter with the photon, \\(\\varepsilon\\). The sensitivity of the SHiP detector is reviewed for dark photons in the mass range between 0.002 and 10 GeV. Different production mechanisms are simulated, with the dark photons decaying to pairs of visible fermions, including both leptons and quarks. Exclusion contours are presented and compared with those of past experiments. The SHiP detector is expected to have a unique sensitivity for m\\(_{\\gamma^{\\mathrm{D}}}\\) ranging between 0.8 and 3.3\\(^{+0.2}_{-0.5}\\) GeV, and \\(\\varepsilon^2\\) ranging between \\(10^{-11}\\) and \\(10^{-17}\\).

We propose to build and operate a detector that, for the first time, will measure the process \\(pp\\to\\nu X\\) at the LHC and search for feebly interacting particles (FIPs) in an unexplored domain. The TI18 tunnel has been identified as a suitable site to perform these measurements due to very low machine-induced background. The detector will be off-axis with respect to the ATLAS interaction point (IP1) and, given the pseudo-rapidity range accessible, the corresponding neutrinos will mostly come from charm decays: the proposed experiment will thus make the first test of the heavy flavour production in a pseudo-rapidity range that is not accessible by the current LHC detectors. In order to efficiently reconstruct neutrino interactions and identify their flavour, the detector will combine in the target region nuclear emulsion technology with scintillating fibre tracking layers and it will adopt a muon identification system based on scintillating bars that will also play the role of a hadronic calorimeter. The time of flight measurement will be achieved thanks to a dedicated timing detector. The detector will be a small-scale prototype of the scattering and neutrino detector (SND) of the SHiP experiment: the operation of this detector will provide an important test of the neutrino reconstruction in a high occupancy environment.

PurposeTo evaluate the maternal and neonatal safety of vaginal delivery in women with HIV following the implementation of a national protocol in Italy.MethodsVaginal delivery was offered to all eligible women who presented antenatally at twelve participating clinical sites. Data collection and definition of outcomes followed the procedures of the National Program on Surveillance on Antiretroviral Treatment in Pregnancy. Pregnancy outcomes were compared according to the mode of delivery, classified as vaginal, elective cesarean (ECS) and non-elective cesarean section (NECS).ResultsAmong 580 women who delivered between January 2012 and September 2017, 142 (24.5%) had a vaginal delivery, 323 (55.7%) had an ECS and 115 (19.8%) had an NECS. The proportion of vaginal deliveries increased significantly over time, from 18.9% in 2012 to 35.3% in 2017 (p < 0.001). Women who delivered vaginally were younger, more commonly nulliparous, diagnosed with HIV during current pregnancy, and antiretroviral-naïve, but had a slightly longer duration of pregnancy, with significantly higher birthweight of newborns. NECS was associated with adverse pregnancy outcomes. The rate of HIV transmission was minimal (0.4%). There were no differences between vaginal and ECS about delivery complications, while NECS was more commonly associated with complications compared to ECS.ConclusionsVaginal delivery in HIV-infected women with suppressed viral load appears to be safe for mother and children. No cases of HIV transmission were observed. Despite an ongoing significant increase, the rate of vaginal delivery remains relatively low compared to other countries, and further progress is needed to promote this mode of delivery in clinical practice.