Cross Section Measurements Research Articles

Recent Results from the FASER Experiment at the LHC

The ForwArd Search ExpeRiment (FASER), is an LHC experiment that aims to: (1) detect and study TeV-energy neutrinos, the most energetic neutrinos ever detected from a humanmade source and (2) search for new light and very weakly interacting particles. The FASER detector is located 480 m downstream of the ATLAS p-p interaction point, along the beam collision axis. FASER was designed, constructed, installed, and commissioned during 2019–2022 and has been taking physics data since the start of LHC Run 3 in July 2022. Recently, FASER reported the first measurement of ve and vμ interaction cross sections at the LHC with its sub-detector FASERv , FASER’s emulsion detector, first results on Axion-Like Particles at FASER and dark photons limits. These results will be reported in this article.

Measurement of flux-weighted average cross-section in the photo-neutron reactions of Nb at the bremsstrahlung end-point energies of 20 MeV and 67 MeV

The photo-neutron flux-weighted average cross-sections for 93Nb(γ,xn) reactions at the bremsstrahlung end-point energies of 20 MeV and 67 MeV have been measured by the activation technique using the electron linear accelerator LUE-75 located at the A.I. Alikhanyan National Science Laboratory (AANL). Furthermore, the isomeric cross-section ratio has been determined for the 89m,gNb isomeric pair. TALYS 1.96 and EMPIRE 3.2 nuclear codes were used to calculate the 93Nb(γ,xn) reaction cross-sections and isomeric ratio as functions of bremsstrahlung end-point energy. The energy distribution of bremsstrahlung photons has been calculated by GEANT4. The measured experimental data has been compared with currently available literature data as well as with the values based on theoretical calculations.

Status and perspective of ICARUS-T600 detector at the Fermilab Short-Baseline Neutrino program

The ICARUS collaboration has employed the 760-ton T600 detector in a successful three-year physics run at the underground LNGS laboratory, performing a search for anomalous νe appearance in the CERN Neutrino to Gran Sasso beam, which contributed to the constraints on the allowed neutrino oscillation parameters to a narrow region around 1 eV. After a significant overhaul at CERN, the T600 detector has been installed at Fermilab. In 2020 the cryogenic commissioning began with detector cool down, liquid argon filling and recirculation. ICARUS started its operation collecting the first neutrino events from the Booster Neutrino Beam and the Neutrinos at the Main Injector beam off-axis, which were used to test the ICARUS event selection, reconstruction and analysis algorithms. ICARUS successfully completed its commissioning phase in June 2022, moving then to data taking for neutrino oscillation physics. In the short term, ICARUS will be able to either confirm or refute the claim by Neutrino-4 short-baseline reactor. At the completion of the Short-Baseline Near Detector, near and far detectors will join within the Fermilab Short-Baseline program searching for evidence of sterile neutrinos. measurements of neutrino cross sections with the NuMI beam and several Beyond-Standard-Model searches. In this presentation, the technical achievements of the ICARUS detector subsystems (Time Projection Chambers, Light Photo-detection System, Cosmic Ray Tagger, Trigger and Data Acquisition) during the commissioning phase and early data taking will be presented; the prospects for the first physics analysis will be reported.

Non-contact measurement method of liquid composition using microwave radar cross-section

This study aims to provide a non-contact detection of liquid composition inside containers using Microwave Radar Cross-section (RCS) measurement technology. Firstly, it analyzes the limitations of traditional near-infrared spectroscopy methods and proposes the necessity of introducing microwave detection methods. The research demonstrates through experiments a significant correlation between polar substances like total acid content and radar scattering capability, showing microwave radar’s effectiveness in reflecting the polarity characteristics of liquids. Furthermore, theoretical derivations and experimental validations illustrate that differences in electromagnetic properties of different liquid components lead to variations in echo loss, thereby impacting RCS levels. Experimental results indicate that microwave radar RCS measurement technology achieves an accuracy level of 2%, capable of distinguishing between different concentrations of ethanol, acetic acid, and other solutions. This study highlights the significant advantages of microwave radar RCS measurement technology in non-contact detection of liquid composition, providing new methods and a technological foundation for precise liquid component detection.

Reactivity Impact of Updated 35Cl Nuclear Data on the Molten Chloride Reactor Experiment

The Molten Chloride Reactor Experiment (MCRE) will be built and operated as part of an Advanced Reactor Demonstration Project Risk Reduction Award. This fast spectrum, chloride salt–fueled molten salt reactor is sensitive to chlorine nuclear data. Recent experimental measurements of the 35Cl (n,p) cross section disagree with 35Cl nuclear data evaluations outside the bounds of the nuclear data uncertainty covariance matrices. To address this challenge, Los Alamos National Laboratory has been charged with measuring the 35Cl (n,p) cross section at the Los Alamos Neutron Science Center and generating an updated 35Cl nuclear data evaluation integrating recent cross-section measurements. This paper evaluates the reactivity impact of using the updated 35Cl evaluation on the MCRE application compared to publicly available evaluations (ENDF/B up to VIII.0 and JENDL-5).

Comparison of fast-neutron-induced reaction cross-sections in [formula omitted], [formula omitted], [formula omitted], [formula omitted], [formula omitted], [formula omitted], and [formula omitted] in quasi-monoenergetic fields of p+Li and d+TiT neutron sources

This paper describes cross-section measurements of fast-neutron-induced reactions using the neutron activation method. The study employed two accelerator-driven fast neutron sources, each possessing distinct characteristics during irradiation of analogous sets of samples. Specifically, the neutron source at the NPI Řež relied on the p+Li(C) reaction, while MONNET at JRC Geel utilized the d+TiT(Ag) reaction for neutron production. Building upon prior experiments conducted at NPI, we present new cross-sections for reactions, some of which suffer from a dearth of experimental data. The results presented in this paper originate from samples of Al, Au, Bi, Co, NaF, and Y that were irradiated with neutrons at energies of 17.6(3) MeV, and 18.5(4) MeV at MONNET, and an energy of 22.5(8) MeV at the NPI. Following neutron irradiation, the samples were analysed using gamma-ray spectrometry. Cross-sections of several fast-neutron-induced reactions were determined on the basis of the measurement of neutron spectra and corresponding reaction yields. By comparing the results of analogous experiments conducted in different experimental setups, it becomes possible to assess systematic uncertainties. The obtained cross-sections may contribute to the further development of both advanced nuclear reactors and to a more precise fast-neutron dosimetry.

Quantifying whole human hair scalp fibres of varying curl: A micro-computed tomographic study.

Scalp hair is a key feature of humans and its variability has been the subject of a broad range of studies. A small subset of these studies has focused on geometric quantification of human scalp hair fibres, however the use of race- and ethnicity-based classification systems makes it challenging to draw objective conclusions about fibre variability. Furthermore, sample preparation techniques for micro-imaging studies often alter the original form of hair fibres. This study sought to determine which of the commonly reported descriptors could be resolved using micro-computed tomography (micro-CT) for fibres of varying curl. Images obtained from micro-CT were used to reconstruct three-dimensional images that were then analysed. The study also explored the capabilities and limitations of micro-CT as an imaging modality by comparing and cross-validating findings with those obtained from scanning electron microscopy (SEM) and laser micrometry. The former deals with surface imaging while the latter deals with cross-sectional measurements. Micro-CT was found to be highly effective at resolving cross-sectional ellipsoidal parameters, but performed more poorly than SEM in reconstructing surface level details at a 2 resolution. The technique was, however, able to reveal the presence of the medulla in type VI (high curl) hair fibres. When compared with high curl fibres, greater intra-fibre variability was observed for the low and medium curl fibres, highlighting the importance more objective classificationsystems.

Measurement of the differential cross section for neutral pion production in charged-current muon neutrino interactions on argon with the MicroBooNE detector

We present a measurement of neutral pion production in charged-current interactions using data recorded with the MicroBooNE detector exposed to Fermilab’s booster neutrino beam. The signal comprises one muon, one neutral pion, any number of nucleons, and no charged pions. Studying neutral pion production in the MicroBooNE detector provides an opportunity to better understand neutrino-argon interactions, and is crucial for future accelerator-based neutrino oscillation experiments. Using a dataset corresponding to 6.86×1020 protons on target, we present single-differential cross sections in muon and neutral pion momenta, scattering angles with respect to the beam for the outgoing muon and neutral pion, as well as the opening angle between the muon and neutral pion. Data extracted cross sections are compared to generator predictions. We report good agreement between the data and the models for scattering angles, except for an over-prediction by generators at muon forward angles. Similarly, the agreement between data and the models as a function of momentum is good, except for an underprediction by generators in the medium momentum ranges, 200–400 MeV for muons and 100–200 MeV for pions. Published by the American Physical Society 2024

Interpretations of the ATLAS measurements of Higgs boson production and decay rates and differential cross-sections in pp collisions at s = 13 TeV

Measurements of the Higgs boson production times decay rates and differential cross-sections have recently been performed by the ATLAS experiment in several decay channels using up to 139 fb−1 of proton-proton collision data at s = 13 TeV recorded at the Large Hadron Collider. This paper presents multiple interpretations of these Higgs boson measurements. Measurements of production-mode cross-sections, simplified template cross-sections and fiducial differential cross-sections in different decay channels are reparameterised in terms of the impact of Standard Model effective field theory operators, and constraints are reported on the corresponding Wilson coefficients. Production and decay rate measurements are interpreted in UV-complete extensions of the Standard Model, namely the two-Higgs-doublet model (2HDM) near the alignment limit and the Minimal Supersymmetric Standard Model (MSSM) for various MSSM benchmark scenarios. The constraints on the 2HDM parameters (cos(β − α), tanβ) and the MSSM parameters (mA, tanβ) are complementary to those obtained from direct searches for additional Higgs bosons.

First measurement of the total inelastic cross section of positively charged kaons on argon at energies between 5.0 and 7.5 GeV

First measurement of the total inelastic cross section of positively charged kaons on argon at energies between 5.0 and 7.5 GeV

GABA and glutamate measurements in temporal cortex of autistic children.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder and presents with challenges in social communication. A hypothesized underlying contributing mechanism is the imbalance in excitation and inhibition (E/I), partly influenced by the levels of excitatory neurotransmitter glutamate (Glu) and inhibitory neurotransmitter γ-aminobutyric acid (GABA) in the brain. Although many have reported the levels of GABA and Glu in the brain, only a few reports address the temporal cortex and then only with a small sample of autistic children, and often only in one hemisphere. We used a macromolecular suppressed edited-magnetic resonance spectroscopy (MRS) sequence to study GABA and Glu (as potential key players influencing E/I) in a large sample of children with ASD in the right and left temporal cortices of children with (N = 56) and without (N = 30) ASD (7-18 years). As a group, children with ASD exhibited no differences in the left hemisphere (GABA and Glu Cohen's |d|: 0.24 and 0.03), but the right hemisphere showed higher GABA and lower Glu concentrations (GABA and Glu Cohen's |d|: 0.53 and 0.65) compared to neurotypicals. Furthermore, a negative association was found between the right hemisphere Glu levels of the ASD group and a clinical assessment tool (r = -0.361, p = 0.022), reflecting autism trait severity (social responsiveness scale). In conclusion, we highlight the chemical abnormalities in children with ASD through a cross-sectional measurement. Longitudinal studies are warranted to determine whether these chemical levels persist or resolve over development.

Measurements of neutron capture cross-section for nuclides of interest in decommissioning (II): 58Fe(n,γ)59Fe

ABSTRACT As nuclear facilities are dismantled in decommissioning, large amounts of various waste are generated. Even more inconveniently, such waste is radioactive due to neutron activation. Thus, the neutron capture cross-sections of nuclides targeted in decommissioning are required to evaluate the radioactivity produced. In this work, 58Fe nuclide was selected among objective nuclides for decommissioning, and its thermal-neutron capture cross-section was measured by a neutron activation method at the graphite thermal column of Kyoto University Research Reactor in 5-MW operation. The thermal-neutron capture cross-section was derived using Westcott’s convention. The present work obtained 1.36 ± 0.03 barns for the58Fe(n,γ)59Fe reaction. The present result supports the JENDL-5 evaluation within 2σ. If updated with currently recommended nuclear data, some of the reported past data would support the present result.

Experimental Validation of the Remote Sensing Method for River Velocity Measurement Using an Open-Source PIV Scheme—Case Study: Antisana River in the Ecuadorian Andes

This study presents the experimental validation of a remote sensing method for river flow velocity measurement, from which discharge is calculated, using Particle Image Velocimetry (PIV) combined with Unmanned Aerial Vehicles (UAVs). The case study focuses on the Antisana River in the Ecuadorian Andes, a region with challenging geography where accurate flow measurement is crucial for hydroelectric projects. The validation results demonstrate that the velocity measurements obtained through PIV closely align with those from standardized traditional methods. Furthermore, integrating technologies such as LiDAR for cross-sectional measurements, along with UAVs, would enable the accurate estimation of discharge in difficult-to-access areas. This approach has the potential to significantly enhance hydrological studies and water resource management in remote regions, especially for hydroelectric projects in the Ecuadorian Andes.

Added value in low-risk pregnancies of longitudinal changes in uterine Doppler and circulating angiogenic factors during the third trimester in predicting term preeclampsia.

To assess the relationship between longitudinal changes in the uterine Doppler velocimetry and the maternal profile of angiogenic factors in the third trimester of pregnancy and to assess their ability to predict term preeclampsia. A cohort of low-risk pregnant women was constructed at second trimester routine scan and scheduled for a uterine Doppler evaluation and measurement of the circulating levels of angiogenic factors at ~30 and ~36 weeks. The performance of both parameters at both time-points and their change over time from the first to the second measurement in predicting term preeclampsia was evaluated by logistic regression and receiver operating characteristic curve (ROC) analyses. A total of 1172 women were analyzed, of which 28 (2.4%) women developed term preeclampsia. At ~30 weeks, a model including the ratio sFlt-1/PlGF (fms-like tyrosine kinase-1/placental growth factor) and the uterine Doppler explained 16.2% of the uncertainty of developing term preeclampsia, while at ~36 weeks the same variables explained 25.2% [p<0.001]. A model including the longitudinal changes of both predictors had an R2 of 26.8%, which was not significantly different from that of the ~36 weeks evaluation [p=0.45]. The area under the curve (AUC) of the ~36 weeks sFlt-1/PlGF ratio was significantly higher than at ~30 weeks (0.86 [0.77-0.94] vs. 0.81 [0.73-0.9]; p=0.043). The AUC of the 30-to-36 week change of the sFlt-1/PlGF ratio (0.85 [0.77-0.94]) did not significantly differ from that of at ~36 weeks (p=0.82). At ~36 weeks, for a 10% of false positives, the sFlt-1/PlGF ratio had a detection rate of 71.4%, with positive and negative likelihood ratios of 7.3 and 0.32, respectively. A cross-sectional measurement of the sFlt-1/PlGF ratio outperforms uterine Doppler in predicting term preeclampsia. The combination of both markers does not improve such prediction, nor the evaluation of the longitudinal changes between ~30 and ~36 weeks.

Towards a new generation of solid total-energy detectors for neutron-capture time-of-flight experiments with intense neutron beams

Challenging neutron-capture cross-section measurements of small cross sections and samples with a very limited number of atoms require high-flux time-of-flight facilities. In turn, such facilities need innovative detection setups that are fast, have low sensitivity to neutrons, can quickly recover from the so-called γ-flash, and offer the highest possible detection sensitivity. In this paper, we present several steps toward such advanced systems. Specifically, we describe the performance of a high-sensitivity experimental setup at CERN n_TOF EAR2. It consists of nine sTED detector modules in a compact cylindrical configuration, two conventional used large-volume C6D6 detectors, and one LaCl3(Ce) detector. The performance of these detection systems is compared using 93Nb(n, γ) data. We also developed a detailed Geant4 Monte Carlo model of the experimental EAR2 setup, which allows for a better understanding of the detector features, including their efficiency determination. This Monte Carlo model has been used for further optimization, thus leading to a new conceptual design of a γ detector array, STAR, based on a deuterated-stilbene crystal array. Finally, the suitability of deuterated-stilbene crystals for the future STAR array is investigaged experimentally utilizing a small stilbene-d12 prototype. The results suggest a similar or superior performance of STAR with respect to other setups based on liquid-scintillators, and allow for additional features such as neutron-gamma discrimination and a higher level of customization capability.

Experimental validation of the Gaseous Proton Recoil Telescope for quasi-absolute neutron flux measurements

The accuracy of neutronics simulations of actual or future reactor cores is nowadays driven by the precision of the nuclear data used as input. Among the most important neutron-induced fission cross sections to understand well are the actinides. It is, indeed, of primary importance to know accurately these cross sections around 1 MeV for the safety of Generation IV reactors. High accuracy measurements of neutron flux are essential for accurate cross section measurements; measurements of this flux with respect to the 1H(n,n)p cross section can be made with the proton recoil technique. For an accurate measurement below 1 MeV, the Gaseous Proton Recoil Telescope (GPRT) is developed and characterized, with the aim to provide quasi-absolute neutron flux measurements with an accuracy better than 2%. This detector is composed of a double ionization chamber with a Micromegas segmented detection plane. The pressure of the gas can be adjusted to protons stopping range — and therefore to neutrons energy. An accurate neutron flux measurement requires that the GPRT has an intrinsic efficiency of 100%, and thus an important effort has been made to verify this. An alpha source and proton micro-beam have been used and the intrinsic efficiency is confirmed to be 100%. Additionally the dead-time of the detector has been investigated on a test bench, and is found to be 7.3 ms.

Measurable progression of giant cell tumour of bone associated with pregnancy - A tertiary sarcoma centre analysis

IntroductionGiant cell tumour of bone (GCTB) is a benign but locally aggressive bone tumour with a higher predilection for females of reproductive age. GCTB management poses a unique set of challenges during pregnancy due to risks associated with imaging and treatment options. Pregnancy has been implicated in GCTB progression and tumour recurrence, however an exact mechanism has not been established. This study aims to confirm the relationship between the diagnosis and progression of GCTB during pregnancy. MethodsA 17-year retrospective analysis of our tertiary sarcoma referral centre database was performed to identify the relevant patients. Pregnancy-associated tumours were defined by those already present or diagnosed during pregnancy, and up to 12 months postpartum. Lesion volume was determined by mathematical ellipsoidal modelling technique to simplify the estimation, with cross-sectional measurements obtained from the three standard orthogonal planes on initial and surveillance imaging. Due to logistical challenges, follow-up imaging was performed at either our tertiary sarcoma centre or under guidance at regional imaging centres convenient to the patient. ResultsThe diagnosis of GCTB was made in 113 female patients during this 17-year period, of which 20 were associated with pregnancy with a mean age of 28.8 years (range 19–40 years). 12 patients had their primary or recurrent GCTB diagnosed, or known tumour progress during pregnancy, whilst the remaining 8 were diagnosed shortly thereafter to within 12 months postpartum. The most common tumour sites were located around the knee (30 %) and distal radius (25 %). A statistically significant pattern of growth was observed through the surveillance period (p 0.018), within a relatively short mean follow-up period of only 89.8 days (SD 54.5; 13–192 days). ConclusionThis study demonstrates the significant association that pregnancy has with the growth and progression of both primary and recurrent GCTB. Pregnant patients should be subject to close surveillance well into the postpartum period due to possible accelerated disease progression and potential for disease recurrence.

Modeling the Process of Critical Exhaustion of Oxygen in a River Caused by Exponential Source of Pollution

The analysis and improvement of the river's change dynamics are critical to the global investigation of water quality issues. This study investigates the mathematical model representation of one dimension of a pair of advection-dispersion equations. These equations pertain to the concentrations of both pollutants and dissolved oxygen. Certain terms, which demonstrate an increase in the decay rate of pollution through exponential sources and assume a decreasing river's cross-sectional measurement, lead to the diminished oxygen levels observed in this study. The crucial points are demonstrated using both analytical and numerical analysis of the steady-state model, which allows for examining multiple situations about the elimination of oxygen and aquatic survival in a river with severe pollution.

Measurement of high-temperature absorption cross-sections using an optical cell with a non-uniform temperature distribution

A mathematical method to enable absorption cross-section measurements using an optical cell with a non-uniform temperature distribution is formulated, validated and experimentally demonstrated in this study. The motivation of the proposed method is to facilitate high-temperature spectroscopic studies in the long-wavelength mid-IR region, and to offer an alternative to highly engineered optical cells. The method is based on virtual segmentation of the non-uniform temperature field within an optical cell into bins, each having a sufficiently uniform temperature. By collecting a set of absorbance measurements corresponding to unique temperature profiles and expressing the temperature dependence of the absorption cross-section in terms of a model with limited number of unknowns, a closed-form system of equations is obtained which can be solved to evaluate absorption cross-sections. It is shown, through a set of simulated validation cases, that modeling the temperature dependence in terms of a third order polynomial results in accurate reconstruction of the cross-section spectra for a wide range of cases. Piece-wise polynomials and an alternative nonlinear model are proposed for improved accuracy and to model potentially complex temperature dependencies of the absorption cross-sections. To demonstrate the application of the proposed method, an optical cell with a non-uniform temperature profile was used to measure the cross-section spectra of methane over 1280 – 1330 cm-1 at temperatures up to 523 K. The proposed method is expected to be highly useful in collecting spectroscopic data at high temperatures particularly in the mid-infrared region.

First 70Zn(p,x) nuclear cross section measurements for theranostic 67Cu radionuclide production extended up to 100 MeV

In this work the nuclear reaction routes 70Zn(p,x)64,67Cu, 66,67Ga, and 65,69mZn, induced by a high-energy proton beam up to 100 MeV have been investigated. Demand for 67Cu is increasing worldwide because it is known to be one of the best radionuclides having theranostic properties. Thus, efforts to improve its global production are underway. In previous studies, experimental data about nuclear cross-section measurements on 70Zn-enriched targets induced by proton beams were limited to an energy range of up to 70 MeV. Our goal was to extend nuclear data on 70Zn over a wider and unexplored so far region from 42 MeV to 98 MeV. As a result, our data turned out to be in good agreement with the literature ones in the overlapping energy range. In addition, to the best of our knowledge, new nuclear data exceeding 70 MeV were provided, demonstrating an excellent analytical method for producing 67Cu in the extended energy range.