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At least 253 records · Page 14

Measurement of the cross section of $$ {e}^{+}{e}^{-}\to {\Xi}^{-}{\overline{\Xi}}^{+} $$ at center-of-mass energies between 3.510 and 4.843 GeV

Abstract Usinge + e − collision data corresponding to a total integrated luminosity of 12.9 fb −1 collected with the BESIII detector at the BEPCII collider, the exclusive Born cross sections and the effective form factors of the reaction$$ {e}^{+}{e}^{-}\to {\Xi}^{-}{\overline{\Xi}}^{+} $$ e + e − → Ξ − Ξ ¯ + are measured via the single baryon-tag method at 23 center-of-mass energies between 3.510 and 4.843 GeV. Evidence for the decay$$ \psi (3770)\to {\Xi}^{-}{\overline{\Xi}}^{+} $$ ψ 3770 → Ξ − Ξ ¯ + is observed with a significance of 4.5σby analyzing the measured cross sections together with earlier BESIII results. For the other charmonium(-like) statesψ(4040),ψ(4160),Y(4230),Y(4360),ψ(4415), andY(4660), no significant signal of their decay to$$ {\Xi}^{-}{\overline{\Xi}}^{+} $$ Ξ − Ξ ¯ + is found. For these states, upper limits of the products of the branching fraction and the electronic partial width at the 90% confidence level are provided.

Physics↗

Measurement of the inclusive WZ production cross section in pp collisions at $\sqrt{\textrm{s}}$ = 13.6 TeV

The inclusive WZ production cross section is measured in proton-proton collisions at a centre-of-mass energy of 13.6 TeV, using data collected during 2022 with the CMS detector, corresponding to an integrated luminosity of 34.7 fb −1 . The measurement uses multileptonic final states and a simultaneous likelihood fit to the number of events in four different lepton flavour categories: eee, ee μ , μμ e, and μμμ . The selection is optimized to minimize the number of background events, and relies on an efficient prompt lepton discrimination strategy. The WZ production cross section is measured in a phase space defined within a 30 GeV window around the Z boson mass, as σ total (pp → WZ) = 55.2 ± 1.2 (stat) ± 1.2 (syst) ± 0.8 (lumi) ± 0.3 (theo) pb. In addition, the cross section is measured in a fiducial phase space closer to the detector-level requirements. All the measurements presented in this paper are in agreement with standard model predictions.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Measurement of exclusive pion pair production in proton–proton collisions at $\sqrt{s}={7}\,\text {TeV}$ with the ATLAS detector

The exclusive production of pion pairs in the process $pp$ → $pp π$ + $π$ - has been measured at $\sqrt{s}={7}\,\text {TeV}$ with the ATLAS detector at the LHC, using $80 µb$ -1 of low-luminosity data. The pion pairs were detected in the ATLAS central detector while outgoing protons were measured in the forward ATLAS ALFA detector system. This rep resents the first use of proton tagging to measure an exclusive hadronic final state at the LHC. A cross-section measurement is performed in two kinematic regions defined by the pro ton momenta, the pion rapidities and transverse momenta, and the pion–pion invariant mass. Cross-section values of $4.8 ± 1.0$ ${(stat)}^{+0.3}_{-0.2}$ $(syst) µ b$ and $9 ± 6$ ${(stat)}^{+2}_{-2}$ $(syst) µ b$ are obtained in the two regions; they are compared with theoretical models and provide a demonstration of the feasibility of measurements of this type.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Threshold charmonium photoproduction with GlueX

Exclusive charmonium photoproduction near threshold opens the door for studying the gluonic properties of the proton: gluonic GPDs, anomalous contribution to the mass of the proton, gravitational form factors, the mass radius of the proton. However, such an ambitious program requires precise measurements to validate the theoretical assumptions that relate the experimental results to the above quantities. The first total cross-section measurements of near-threshold exclusive J/? photoproduction (?p?J/?p) by the GlueX collaboration sparked remarkable theoretical interest, however had limited statistics. We will report new total cross-section results based on more than a four-fold increase in statistics. Even more, due to the full acceptance of the GlueX experiment for this reaction, we will present first measurements of the differential cross-sections over the whole near-threshold kinematic region. Such measurements enable more general conclusions about the reaction mechanism when compared to a wide range of theoretical predictions including GPD calculations and models with open-charm intermediate states.

Pentchev, Lubomir↗

Inclusive Charged-Current Electron Neutrino Interactions in SBND

The Short-Baseline Near Detector (SBND), a 112 ton liquid argon time projection chamber (LArTPC), is the near detector of the Short- Baseline Neutrino Program at Fermilab. Due to its proximity to the Booster Neutrino Beam target, SBND has already seen a record-breaking number of electron neutrino interactions on argon. We present preliminary results from SBND’s differential inclusive electron neutrino charged-current analysis from our first year of beam data, selecting over 2,000 interactions. This analysis will present the largest sample of electron neutrinos on argon to date, as well as the first differential cross section measurement of electron neutrinos. This poster will give an overview of the selection, cross-section extraction, and demonstrate SBND’s detector and electromagnetic shower reconstruction performance through data/MC comparisons.

Tung, Lynn [Chicago U.]↗

$\nu$-Ar Interaction Measurements in the NuMI Beam at ICARUS

This work presents progress toward neutrino-Ar cross-section measurements at ICARUS using the NuMI beam. ICARUS observes muon and electron neutrino interactions in the GeV energy range. Measurements of these interactions offer unique opportunities to infer neutrino interaction cross sections on an argon nuclear target within an energy range that overlaps both the SBN oscillation search and a significant portion of the DUNE spectrum.

Salmoria, Gabrieli [Parana Tech. Fed. U., Toledo] ↗

Recognizing Unrecognized Sources of Uncertainty (USU) in Nuclear Data

Historically, time-of-flight (TOF) nuclear cross section measurements on different nuclides are assumed to be uncorrelated if they were recorded in different facilities with identical methods, identical facilities with different methods, and even identical facilities with identical methods. Ideally, measurements of different nuclides would truly be uncorrelated thus providing independent assessments of some cross section. In reality, correlations exist between measurements but are simply assumed to be unimportant. To eliminate these qualitative assumptions, in this paper we make a counter-intuitive suggestion to perform an intentionally correlated measurement of energy-differential fission and capture reactions for nuclides in a single criticality safety benchmark during a single experimental campaign. While this would introduce undesirable correlations, it would fully quantify correlations between datasets, rather than assume that the correlations do not exist.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

VAIM-CFF: a variational autoencoder inverse mapper solution to Compton form factor extraction from deeply virtual exclusive reactions

We develop a new methodology for extracting Compton form factors (CFFs) from deeply virtual exclusive reactions such as the unpolarized DVCS cross section using a specialized inverse problem solver, a variational autoencoder inverse mapper (VAIM). The VAIM-CFF framework not only allows us access to a fitted solution set possibly containing multiple solutions in the extraction of all 8 CFFs from a single cross section measurement, but also accesses the lost information contained in the forward mapping from CFFs to cross section. We investigate various assumptions and their effects on the predicted CFFs such as cross section organization, number of extracted CFFs, use of uncertainty quantification technique, and inclusion of prior physics information. We then use dimensionality reduction techniques such as principal component analysis to visualize the missing physics information tracked in the latent space of the VAIM framework. Through re-framing the extraction of CFFs as an inverse problem, we gain access to fundamental properties of the problem not comprehensible in standard fitting methodologies: exploring the limits of the information encoded in deeply virtual exclusive experiments.

Accelerator Physics↗

MicroBooNE Electron-Neutrino Cross-Section Results

Measurement of the electron-neutrino cross-section with argon ($\nu$-Ar) is crucial for current and future neutrino experiments. Results from MicroBooNE detector, a liquid argon time projection chamber (LArTPC) based at Fermilab, provide the most extensive and precise determination of these electron-neutrino cross-sections. MicroBooNE is situated on both on-axis and off-axis beams: the Booster Neutrino Beam (BNB) and Neutrinos at the Main Injector (NuMI) beam, respectively. The background for both beams is dominated by showers from neutral pion decay, necessitating an electron-photon separation technique. In this proceeding, we review three recent electron-neutrino cross-section results from MicroBooNE using NuMI and BNB.

Guzzo, Marina [Edinburgh U.]↗

Multi-Differential Charged Current 𝝂_𝝁− Argon Cross Section without Pions in the Final State Measurement in MicroBooNE , and Current Status of Simultaneous Cross Section Extraction with ANNIE

MicroBooNE, an 85-tonne liquid argon time projection chamber detector is on-axis to the Booster Neutrino Beam (BNB) at Fermi National Accelerator Laboratory. MicroBooNE is elucidating neutrino interactions with argon through cross-section measurements to refine interaction models and reduce uncertainties. In this poster, we present recent published single and double multi-differential charged current (CC) cross section with zero pions in the final state (CC-0 ) as a function of muon momentum ( ) and the cosine of the muon angle ( ). We present the details of the event selection and the extraction of 1D and 2D cross sections. We further report on the status of a simultaneous cross-section extraction conducted in conjunction with the ANNIE experiment, which employs a Gd-H O target and operates on the same BNB beamline. This joint measurement enables a precision test of nuclear A-dependence between oxygen and argon, with shared flux and cross-section model correlations leading to the cancellation of systematic uncertainties.

Nguyen, Christian Van [Rutgers U., Piscataway] (OR↗

Measurement of charge state distributions using a scintillation screen

Absolute cross sections measured using electromagnetic devices to separate and detect heavy recoiling ions need to be corrected for charge state fractions. Accurate prediction of charge state distributions using theoretical models is not always a possibility, especially in energy and mass regions where data is sparse. As such, it is often necessary to measure charge state fractions directly. In this paper we present a novel method of using a scintillation screen along with a CMOS camera to image the charge dispersed beam after a set of magnetic dipoles. A measurement of the charge state distribution for 88 Sr passing through a natural carbon foil is performed. Using a Bayesian model to extract statistically meaningful uncertainties from these images, we find agreement between the new method and a more traditional method using Faraday cups. Additional future work is need to better understand systematic uncertainties. Our technique offers a viable method to measure charge state distributions.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Measurement of differential cross sections and charge ratios for t -channel single top quark production in proton–proton collisions at $\sqrt{s}=13$ $\,\text {Te}\text {V}$

A measurement is presented of differential cross sections for t-channel single top quark and antiquark production in proton–proton collisions at a centre-of-mass energy of 13$\,\text {Te}\text {V}$ by the CMS experiment at the LHC. From a data set corresponding to an integrated luminosity of 35.9$\,\text {fb}^{-1}$, events containing one muon or electron and two or three jets are analysed. The cross section is measured as a function of the top quark transverse momentum ($p_{\mathrm{T}} $), rapidity, and polarisation angle, the charged lepton $p_{\mathrm{T}} $ and rapidity, and the $p_{\mathrm{T}} $ of the $\text {W}{}{}$ boson from the top quark decay. In addition, the charge ratio is measured differentially as a function of the top quark, charged lepton, and $\text {W}{}{}$ boson kinematic observables. The results are found to be in agreement with standard model predictions using various next-to-leading-order event generators and sets of parton distribution functions. Additionally, the spin asymmetry, sensitive to the top quark polarisation, is determined from the differential distribution of the polarisation angle at parton level to be $0.440 \pm 0.070$, in agreement with the standard model prediction.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Studies of Single-Transverse Kinematic Variables for Neutrino Interactions on Argon

It is now well-known that a variety of theoretically-challenging nuclear effects play an important role in determining neutrino-nucleus interaction cross sections. Deficiencies in existing models of these effects represent a leading source of systematic uncertainty for neutrino oscillation experiments. In recent neutrino cross section measurements published by the T2K and MINERvA experiments, the study of kinematic observables called Single-Transverse (Kinematic) Variables (STVs) in the plane transverse to the neutrino beam have been demonstrated to provide a powerful tool on nuclear modeling uncertainties. In the near future, the SBN and DUNE experiments will both leverage the novel Liquid Argon Time Projection Chamber technology to pursue high-precision measurements of neutrino oscillations. As the interpretation of the results from these measurements will require a detailed understanding of neutrino-argon scattering cross sections and given the scarcity of available neutri no-argon data, a measurement of Single-Transverse Kinematic Variables distributions in neutrino-argon scattering is of high interest for the neutrino physics community. This thesis presents the first detailed comparison of model predictions for distributions of these observables obtained using four standard neutrino event simulation tools (GENIE, NuWro, GiBUU and NEUT). Results are shown for simulations of muon neutrinos from the Fermilab Booster Neutrino Beam interacting in the MicroBooNE LArTPC. Opportunities for discrimination between nuclear models with respect to future measurements is highlighted. Furthermore, first calculations of STVs from experimental argon data are shown. Data corresponding to 4.449x10^19 POT of exposure were collected using the MicroBooNE LArTPC in the Fermilab Booster Neutrino Beam.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Measurements of WH and ZH production with Higgs boson decays into bottom quarks and direct constraints on the charm Yukawa coupling in 13 TeV pp collisions with the ATLAS detector

A study of the Higgs boson decaying into bottom quarks (H → $b\bar{b}$) and charm quarks (H → $c\bar{c}$) is performed, in the associated production channel of the Higgs boson with a W or Z boson, using 140 fb −1 of proton-proton collision data at $\sqrt{s}$ = 13 TeV collected by the ATLAS detector. The individual production of WH and ZH with H → $b\bar{b}$ is established with observed (expected) significances of 5.3 (5.5) and 4.9 (5.6) standard deviations, respectively. Differential cross-section measurements of the gauge boson transverse momentum within the simplified template cross-section framework are performed in a total of 13 kinematical fiducial regions.

Hadron-Hadron Scattering↗

Measurement of vector boson production cross sections and their ratios using pp collisions at s = 13.6 TeV with the ATLAS detector

Fiducial and total W± and Z boson cross sections, their ratios and the ratio of top-antitop-quark pair and W-boson fiducial cross sections are measured in proton–proton collisions at a centre-of-mass energy of s=13.6 TeV, corresponding to an integrated luminosity of 29 fb−1 of data collected in 2022 by the ATLAS experiment at the Large Hadron Collider. The measured fiducial cross-section values for W+→ℓ+ν, W−→ℓ−ν¯, and Z→ℓ+ℓ− (ℓ=e or μ) boson productions are 4250±150 pb, 3310±120 pb, and 744±20 pb, respectively, where the uncertainty is the total uncertainty, including that arising from the luminosity of about 2.2%. The measurements are in agreement with Standard-Model predictions calculated at next-to-next-to-leading-order in αs, next-to-next-to-leading logarithmic accuracy and next-to-leading-order electroweak accuracy.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Identification of Final-State Neutrons in ANNIE

The Accelerator Neutrino Neutron Interaction Experiment (ANNIE) is a 26-ton gadolinium-loaded (Gd-loaded) water Cherenkov detector located on the Booster Neutrino beamline at Fermilab. ANNIE's primary physics objectives include measuring neutron multiplicity for neutrino-nucleus interactions and performing cross-section measurements of charge current quasi-elastic and neutral current quasi-elastic processes. These measurements aim to improve neutrino energy reconstruction and reduce uncertainties in current and future neutrino oscillation experiments. Additionally, ANNIE serves as a testbed for advanced technologies such as Large Area Picosecond Photodetectors (LAPPDs) and Water-Based Liquid Scintillator, which enhance vertex resolution and enable detection below the Cherenkov threshold. By leveraging the high neutron capture cross section of Gd-loaded water, ANNIE is well positioned to observe final-state neutrons in beam-correlated neutrino interactions. To constrain the uncertainties in the neutron capture efficiency and time within the detector, we have conducted multiple calibration campaigns using an AmBe source. The AmBe source is deployed at different locations of the tank to map the neutron capture efficiency and determine the expected neutron capture time. Additionally, the AmBe calibration data are used to define the precise neutron clustering that will be useful for identifying neutron-like clusters from neutrino interaction. In this poster, we will present the current status of the AmBe neutron calibration program and the development of neutron cluster definition for the ANNIE Experiment.

Ajana, Dhavalkumar [Florida State U.]↗

Measurement of differential cross sections for Z bosons produced in association with charm jets in pp collisions at $\sqrt{s} =$ 13 TeV

Measurements are presented of differential cross sections for the production of Z bosons in association with at least one jet initiated by a charm quark in pp collisions at $ \sqrt{s} $ = 13 TeV. The data recorded by the CMS experiment at the LHC correspond to an integrated luminosity of 35.9 fb$^{−1}$. The final states contain a pair of electrons or muons that are the decay products of a Z boson, and a jet consistent with being initiated by a charm quark produced in the hard interaction. Differential cross sections as a function of the transverse momentum p$_{T}$ of the Z boson and p$_{T}$ of the charm jet are compared with predictions from Monte Carlo event generators. The inclusive production cross section 405.4 ± 5.6 (stat) ± 24.3 (exp) ± 3.7 (theo) pb, is measured in a fiducial region requiring both leptons to have pseudorapidity |η| < 2.4 and p$_{T}$> 10 GeV, at least one lepton with p$_{T}$> 26 GeV, and a mass of the pair in the range 71–111 GeV, while the charm jet is required to have p$_{T}$> 30 GeV and |η| < 2.4. These are the first measurements of these cross sections in proton-proton collisions at 13 TeV.[graphic not available: see fulltext]

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Measurement of $d^2 \sigma/d|\vec{q}|d E_{avail}$ and 2p2h contribution using charged current $\nu_\mu$ interactions in the NOvA Near Detector

This Thesis presents the analysis methods and measurement of the $d^2 \sigma/d|\vec{q}|d E_{avail}$-CC inclusive cross section that describes neutrino scattering in a predominantly hydrocarbon medium. Studies that are prerequisite for the analysis including, variable determinations, event selections, efficiency, purity determinations, and systematic uncertainty estimations, are summarized. Tests of the analysis are also detailed, and shown to reproduce the input distributions. The double-differential cross-section measurement provides the foundation for determination of the inclusive rate for the excess induced by 2p2h processes together with nuclear medium effects that are not described by the Fermi gas model. The methodology for the extraction of this rate, defined as the excess observed relative to the rate estimated for known single-nucleon interactions, is described in detail. The following new measurements are reported in this Thesis: (1) The $\nu_\mu-$CC inclusive double-differential cross section as a function of three-momentum transfer and available hadronic energy, for an average $E_\nu$ of 1.8 GeV, is obtained. The double-differential cross section value that obtains when the bin widths are taken to be the dimensions of the entire analysis domain, e.g. $0.2 \le |\vec{q}| \le 2.0 GeV/c$ and $0.0 \le E_{avail} \le 2.0$ GeV, is inclusive cross section is $(6.05 \pm 0.75)\times10^{-39}$ cm$^2$/GeV/GeV/$c$/nucleon. An event excess attributed to 2p2h-MEC processes is observed; most of the rate occurs in a contiguous phase space region $0.3 \le |\vec{q}| \le 1.0$ GeV$/c$ $0.0 \le E_{avail} \le 0.35$ GeV. This rate represents $12.0\pm 6.5\%$ of the observed CC inclusive cross section; its cross section ratio relative to CCQE scattering is estimated to be $44.3 \pm 23.9\%$.

Olson, Travis Grant↗