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Heavy-flavor hadronization mechanism from pp to AA collisions: a theoretical perspective
No full textThe interest in studying heavy-flavor hadronization in high-energy nuclear collisions is twofold. On one hand hadronization represents a source of systematic uncertainties in phenomenological attempts of extracting heavy-flavor transport coefficients in the Quark Gluon Plasma which one assumes to be produced in the collision. Hence, developing the most possible reliable model for this process is important to get a precise and accurate estimate of a fundamental property of hot QCD. On the other hand studying how hadronization changes in the presence of a dense medium of colored partons can be considered an issue of interest by itself. In particular, the observation of modifications of heavy-flavor hadronization in proton-proton collisions strongly suggests that also in this case a small droplet of Quark-Gluon Plasma can be formed. Here we try to provide a general overview on heavy-flavor hadronization, from pp to AA collisions, stressing the aspects and challenges common to all mechanisms proposed in the literature. Then, focusing on a particular model, we show how a consistent description of several observables involving heavy-flavor hadrons can be obtaine
Quantum collider probes of the fermionic Higgs portal
No full textWe explore the sensitivity of future hadron colliders to constrain the fermionic Higgs portal, with a focus on scenarios where the new fermions cannot be directly observed in exotic Higgs decays. This portal emerges in various models including twin-Higgs scenarios and dark matter models, posing significant challenges for collider tests. Working in an effective field theory (EFT), we determine the reach of the high-luminosity option of the Large Hadron Collider (HL-LHC), the high-energy upgrade of the LHC (HE-LHC) and a proposed Future Circular Collider (FCC) in probing the fermionic Higgs portal through off-shell and double-Higgs production. Notably, we find that quantum-enhanced indirect probes offer a better sensitivity than other direct Higgs measurements. We argue that this finding is valid in a wide class of ultraviolet realisations of the EFT. Our study presents a roadmap of a multifaceted search strategy for exploring the fermionic Higgs portal at forthcoming hadron machines
Factorization and resummation at next-to-leading-power
No full textWe discuss recent progress concerning the resummation of large logarithms at next-to-leading power (NLP) in scattering processes such as Drell-Yan and deep inelastic scattering near threshold, and thrust in the two-jet limit. We start by reviewing the approach based on soft-collinear effective field theory and show that the standard factorization into short distance coefficients, collinear and soft functions at NLP leads in general to the appearance of endpoint divergences, which prevent the naive application of resummation techniques based on the renormalization group. Taking thrust as a case study, we then show that these singularities are indeed an artifact of the effective theory, and discuss how they can be removed to recover a finite factorization theorem and achieve resummation at NLP, at LL accuracy. Last, we discuss recent work concerning the calculation of all collinear and soft functions necessary to reproduce Drell-Yan near threshold up to NNLO in perturbation theory. This calculation provides useful data to extend resummation at NLP beyond LL accuracy
<math><mrow><msup><mi>K</mi><mo>*</mo></msup><msup><mrow><mo>(</mo><mn>892</mn><mo>)</mo></mrow><mo>±</mo></msup></mrow></math> resonance production in Pb-Pb collisions at <math><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo>=</mo><mn>5.02</mn></mrow></math> TeV
No full textThe production of K*(892)± meson resonance is measured at midrapidity (|y|<0.5) in Pb-Pb collisions at sNN=5.02 TeV using the ALICE detector at the CERN Large Hadron Collider. The resonance is reconstructed via its hadronic decay channel K*(892)±→KS0π±. The transverse momentum distributions are obtained for various centrality intervals in the pT range of 0.4-16 GeV/c. Measurements of integrated yields, mean transverse momenta, and particle yield ratios are reported and found to be consistent with previous ALICE measurements for K*(892)0 within uncertainties. The pT-integrated yield ratio 2K*(892)±/(K++K−) in central Pb-Pb collisions shows a significant suppression at a level of 9.3σ relative to pp collisions. Thermal model calculations result in an overprediction of the particle yield ratio. Although both hadron resonance gas in partial chemical equilibrium (HRG-PCE) and music + smash simulations consider the hadronic phase, only HRG-PCE accurately represents the measurements, whereas music + smash simulations tend to overpredict the particle yield ratio. These observations, along with the kinetic freeze-out temperatures extracted from the yields measured for light-flavored hadrons using the HRG-PCE model, indicate a finite hadronic phase lifetime, which decreases with increasing collision centrality percentile. The pT-differential yield ratios 2K*(892)±/(K++K−) and 2K*(892)±/(π++π−) are presented and compared with measurements in pp collisions at s=5.02 TeV. Both particle ratios are found to be suppressed by up to a factor of five at pT<2.0 GeV/c in central Pb-Pb collisions and are qualitatively consistent with expectations for rescattering effects in the hadronic phase. The nuclear modification factor (RAA) shows a smooth evolution with centrality and is found to be below unity at pT>8 GeV/c, consistent with measurements for other light-flavored hadrons. The smallest values are observed in most central collisions, indicating larger energy loss of partons traversing the dense medium
Python Monte Carlo Simulation Read Tool
No full text<p>pyMCSRT contains reading modules: one for reading the MCNP mesh tally out format, the other one for reading the PHITS output tally format.</p>
Software Performance of the ATLAS Track Reconstruction for LHC Run 3
No full textCharged particle reconstruction in the presence of many simultaneous proton–proton () collisions in the LHC is a challenging task for the ATLAS experiment's reconstruction software due to the combinatorial complexity. This paper describes the major changes made to adapt the software to reconstruct high-activity collisions with an average of 50 or more simultaneous interactions per bunch crossing (pile-up) promptly using the available computing resources. The performance of the key components of the track reconstruction chain and its dependence on pile-up are evaluated, and the improvement achieved compared to the previous software version is quantified. For events with an average of collisions per bunch crossing, the updated track reconstruction is twice as fast as the previous version, without significant reduction in reconstruction efficiency and while reducing the rate of combinatorial fake tracks by more than a factor two
HEPScore: A new CPU benchmark for the WLCG
No full textHEPScore is a new CPU benchmark created to replace the HEPSPEC06 benchmark that is currently used by the WLCG for procurement, computing resource pledges, usage accounting and performance studies. The development of the new benchmark, based on HEP applications or workloads, has involved many contributions from software developers, data analysts, experts of the experiments, representatives of several WLCG computing centres and WLCG site managers. In this contribution, we review the selection of workloads and the validation of the new HEPScore benchmark
A Joint Fermi-GBM and Swift-BAT Analysis of Gravitational-wave Candidates from the Third Gravitational-wave Observing Run
No full textWe present Fermi Gamma-ray Burst Monitor (Fermi-GBM) and Swift Burst Alert Telescope (Swift-BAT) searches for gamma-ray/X-ray counterparts to gravitational-wave (GW) candidate events identified during the third observing run of the Advanced LIGO and Advanced Virgo detectors. Using Fermi-GBM onboard triggers and subthreshold gamma-ray burst (GRB) candidates found in the Fermi-GBM ground analyses, the Targeted Search and the Untargeted Search, we investigate whether there are any coincident GRBs associated with the GWs. We also search the Swift-BAT rate data around the GW times to determine whether a GRB counterpart is present. No counterparts are found. Using both the Fermi-GBM Targeted Search and the Swift-BAT search, we calculate flux upper limits and present joint upper limits on the gamma-ray luminosity of each GW. Given these limits, we constrain theoretical models for the emission of gamma rays from binary black hole mergers
Search for Inelastic Dark Matter in Events with Two Displaced Muons and Missing Transverse Momentum in Proton-Proton Collisions at <math display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>13</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math>
No full textA search for dark matter in events with a displaced nonresonant muon pair and missing transverse momentum is presented. The analysis is performed using an integrated luminosity of 138 fb-1 of proton-proton (pp) collision data at a center-of-mass energy of 13 TeV produced by the LHC in 2016–2018. No significant excess over the predicted backgrounds is observed. Upper limits are set on the product of the inelastic dark matter production cross section σ(pp→A′→χ1χ2) and the decay branching fraction B(χ2→χ1μ+μ-), where A′ is a dark photon and χ1 and χ2 are states in the dark sector with near mass degeneracy. This is the first dedicated collider search for inelastic dark matter
Dataset related to article \"Anti-SARS-CoV-2 IgG Antibody Response in Individuals Infected Post Complete Vaccination: A 6-Month Longitudinal Study in Healthcare Professionals\
No full text<p>Dati imputati: 1 foglio Excel contenente le informazioni raccolte per le analisi statistiche effettuate per lo studio.</p>\n\n<p>Leggenda:</p>\n\n<ul>\n\t<li>\n\t<p>ID: identificatore del campione anonimizzato</p>\n\t</li>\n\t<li>\n\t<p>Age: età del volontario alla prima acquisizione del campione biologico</p>\n\t</li>\n\t<li>\n\t<p>Sex: sesso del volontario</p>\n\t</li>\n\t<li>\n\t<p>effetti.collaterali: effetti collaterali dopo inoculazione del vaccino</p>\n\t</li>\n\t<li>\n\t<p>covid: infezione da Covid-19</p>\n\t</li>\n\t<li>\n\t<p>data infezione: data infezione da Covid-19</p>\n\t</li>\n\t<li>\n\t<p>M4D2: livello di anticorpi anti Covid-19 4 mesi dopo la seconda dose di vaccino</p>\n\t</li>\n\t<li>\n\t<p>M6D2: livello di anticorpi anti Covid-19 6 mesi dopo la seconda dose di vaccino</p>\n\t</li>\n\t<li>\n\t<p>P3D: livello di anticorpi anti Covid-19 6 al momento di inoculazione della terza dose di vaccino</p>\n\t</li>\n\t<li>\n\t<p>M1D3: livello di anticorpi anti Covid-19 1 mese dopo la terza dose di vaccino</p>\n\t</li>\n\t<li>\n\t<p>M2D3: livello di anticorpi anti Covid-19 2 mesi dopo la terza dose di vaccino</p>\n\t</li>\n\t<li>\n\t<p>M4D3: livello di anticorpi anti Covid-19 4 mesi dopo la terza dose di vaccino</p>\n\t</li>\n\t<li>\n\t<p>M6D3: livello di anticorpi anti Covid-19 6 mesi dopo la terza dose di vaccino</p>\n\t</li>\n\t<li>\n\t<p>sintomi.generici: descrizione sintomi da infezione da Covid-19</p>\n\t</li>\n\t<li>\n\t<p>sintomi: sintomi da infezione da Covid-19 classificati per livello di severità</p>\n\t</li>\n</ul>