First Search for Dark-Trident Processes Using the MicroBooNE Detector.

We present a first search for dark-trident scattering in a neutrino beam using a dataset corresponding to 7.2×10^{20} protons on target taken with the MicroBooNE detector at Fermilab. Proton interactions in the neutrino target at the main injector produce π^{0} and η mesons, which could decay into dark-matter (DM) particles mediated via a dark photon A^{'}. A convolutional neural network is trained to identify interactions of the DM particles in the liquid-argon time projection chamber (LArTPC) exploiting its imagelike reconstruction capability. In the absence of a DM signal, we provide limits at the 90% confidence level on the squared kinematic mixing parameter ϵ^{2} as a function of the dark-photon mass in the range 10≤M_{A^{'}}≤400 MeV. The limits cover previously unconstrained parameter space for the production of fermion or scalar DM particles χ for two benchmark models with mass ratios M_{χ}/M_{A^{'}}=0.6 and 2 and for dark fine-structure constants 0.1≤α_{D}≤1.

First Measurement of η Meson Production in Neutrino Interactions on Argon with MicroBooNE.

We present a measurement of η production from neutrino interactions on argon with the MicroBooNE detector. The modeling of resonant neutrino interactions on argon is a critical aspect of the neutrino oscillation physics program being carried out by the DUNE and Short Baseline Neutrino programs. η production in neutrino interactions provides a powerful new probe of resonant interactions, complementary to pion channels, and is particularly suited to the study of higher-order resonances beyond the Δ(1232). We measure a flux-integrated cross section for neutrino-induced η production on argon of 3.22±0.84(stat)±0.86(syst) 10^{-41} cm^{2}/nucleon. By demonstrating the successful reconstruction of the two photons resulting from η production, this analysis enables a novel calibration technique for electromagnetic showers in GeV accelerator neutrino experiments.

Search for Heavy Neutral Leptons in Electron-Positron and Neutral-Pion Final States with the MicroBooNE Detector.

We present the first search for heavy neutral leptons (HNLs) decaying into νe^{+}e^{-} or νπ^{0} final states in a liquid-argon time projection chamber using data collected with the MicroBooNE detector. The data were recorded synchronously with the NuMI neutrino beam from Fermilab's main injector corresponding to a total exposure of 7.01×10^{20} protons on target. We set upper limits at the 90% confidence level on the mixing parameter |U_{µ4}|^{2} in the mass ranges 10≤m_{HNL}≤150 MeV for the νe^{+}e^{-} channel and 150≤m_{HNL}≤245 MeV for the νπ^{0} channel, assuming |U_{e4}|^{2}=|U_{τ4}|^{2}=0. These limits represent the most stringent constraints in the mass range 35

First Double-Differential Measurement of Kinematic Imbalance in Neutrino Interactions with the MicroBooNE Detector.

We report the first measurement of flux-integrated double-differential quasielasticlike neutrino-argon cross sections, which have been made using the Booster Neutrino Beam and the MicroBooNE detector at Fermi National Accelerator Laboratory. The data are presented as a function of kinematic imbalance variables which are sensitive to nuclear ground-state distributions and hadronic reinteraction processes. We find that the measured cross sections in different phase-space regions are sensitive to different nuclear effects. Therefore, they enable the impact of specific nuclear effects on the neutrino-nucleus interaction to be isolated more completely than was possible using previous single-differential cross section measurements. Our results provide precision data to help test and improve neutrino-nucleus interaction models. They further support ongoing neutrino-oscillation studies by establishing phase-space regions where precise reaction modeling has already been achieved.

First Measurement of Quasielastic Λ Baryon Production in Muon Antineutrino Interactions in the MicroBooNE Detector.

We present the first measurement of the cross section of Cabibbo-suppressed Λ baryon production, using data collected with the MicroBooNE detector when exposed to the neutrinos from the main injector beam at the Fermi National Accelerator Laboratory. The data analyzed correspond to 2.2×10^{20} protons on target running in neutrino mode, and 4.9×10^{20} protons on target running in anti-neutrino mode. An automated selection is combined with hand scanning, with the former identifying five candidate Λ production events when the signal was unblinded, consistent with the GENIE prediction of 5.3±1.1 events. Several scanners were employed, selecting between three and five events, compared with a prediction from a blinded Monte Carlo simulation study of 3.7±1.0 events. Restricting the phase space to only include Λ baryons that decay above MicroBooNE's detection thresholds, we obtain a flux averaged cross section of 2.0_{-1.7}^{+2.2}×10^{-40} cm^{2}/Ar, where statistical and systematic uncertainties are combined.

First Constraints on Light Sterile Neutrino Oscillations from Combined Appearance and Disappearance Searches with the MicroBooNE Detector.

We present a search for eV-scale sterile neutrino oscillations in the MicroBooNE liquid argon detector, simultaneously considering all possible appearance and disappearance effects within the 3+1 active-to-sterile neutrino oscillation framework. We analyze the neutrino candidate events for the recent measurements of charged-current ν_{e} and ν_{µ} interactions in the MicroBooNE detector, using data corresponding to an exposure of 6.37×10^{20} protons on target from the Fermilab booster neutrino beam. We observe no evidence of light sterile neutrino oscillations and derive exclusion contours at the 95% confidence level in the plane of the mass-squared splitting Δm_{41}^{2} and the sterile neutrino mixing angles θ_{µe} and θ_{ee}, excluding part of the parameter space allowed by experimental anomalies. Cancellation of ν_{e} appearance and ν_{e} disappearance effects due to the full 3+1 treatment of the analysis leads to a degeneracy when determining the oscillation parameters, which is discussed in this Letter and will be addressed by future analyses.

Search for an Excess of Electron Neutrino Interactions in MicroBooNE Using Multiple Final-State Topologies.

We present a measurement of ν_{e} interactions from the Fermilab Booster Neutrino Beam using the MicroBooNE liquid argon time projection chamber to address the nature of the excess of low energy interactions observed by the MiniBooNE Collaboration. Three independent ν_{e} searches are performed across multiple single electron final states, including an exclusive search for two-body scattering events with a single proton, a semi-inclusive search for pionless events, and a fully inclusive search for events containing all hadronic final states. With differing signal topologies, statistics, backgrounds, reconstruction algorithms, and analysis approaches, the results are found to be either consistent with or modestly lower than the nominal ν_{e} rate expectations from the Booster Neutrino Beam and no excess of ν_{e} events is observed.

First Measurement of Energy-Dependent Inclusive Muon Neutrino Charged-Current Cross Sections on Argon with the MicroBooNE Detector.

We report a measurement of the energy-dependent total charged-current cross section σ(E_{ν}) for inclusive muon neutrinos scattering on argon, as well as measurements of flux-averaged differential cross sections as a function of muon energy and hadronic energy transfer (ν). Data corresponding to 5.3×10^{19} protons on target of exposure were collected using the MicroBooNE liquid argon time projection chamber located in the Fermilab booster neutrino beam with a mean neutrino energy of approximately 0.8 GeV. The mapping between the true neutrino energy E_{ν} and reconstructed neutrino energy E_{ν}^{rec} and between the energy transfer ν and reconstructed hadronic energy E_{had}^{rec} are validated by comparing the data and Monte Carlo (MC) predictions. In particular, the modeling of the missing hadronic energy and its associated uncertainties are verified by a new method that compares the E_{had}^{rec} distributions between data and a MC prediction after constraining the reconstructed muon kinematic distributions, energy, and polar angle to those of data. The success of this validation gives confidence that the missing energy in the MicroBooNE detector is well modeled and underpins first-time measurements of both the total cross section σ(E_{ν}) and the differential cross section dσ/dν on argon.

Search for Neutrino-Induced Neutral-Current Δ Radiative Decay in MicroBooNE and a First Test of the MiniBooNE Low Energy Excess under a Single-Photon Hypothesis.

We report results from a search for neutrino-induced neutral current (NC) resonant Δ(1232) baryon production followed by Δ radiative decay, with a ⟨0.8⟩ GeV neutrino beam. Data corresponding to MicroBooNE's first three years of operations (6.80×10^{20} protons on target) are used to select single-photon events with one or zero protons and without charged leptons in the final state (1γ1p and 1γ0p, respectively). The background is constrained via an in situ high-purity measurement of NC π^{0} events, made possible via dedicated 2γ1p and 2γ0p selections. A total of 16 and 153 events are observed for the 1γ1p and 1γ0p selections, respectively, compared to a constrained background prediction of 20.5±3.65(syst) and 145.1±13.8(syst) events. The data lead to a bound on an anomalous enhancement of the normalization of NC Δ radiative decay of less than 2.3 times the predicted nominal rate for this process at the 90% confidence level (C.L.). The measurement disfavors a candidate photon interpretation of the MiniBooNE low-energy excess as a factor of 3.18 times the nominal NC Δ radiative decay rate at the 94.8% C.L., in favor of the nominal prediction, and represents a greater than 50-fold improvement over the world's best limit on single-photon production in NC interactions in the sub-GeV neutrino energy range.

Search for a Higgs Portal Scalar Decaying to Electron-Positron Pairs in the MicroBooNE Detector.

We present a search for the decays of a neutral scalar boson produced by kaons decaying at rest, in the context of the Higgs portal model, using the MicroBooNE detector. We analyze data triggered in time with the Fermilab NuMI neutrino beam spill, with an exposure of 1.93×10^{20} protons on target. We look for monoenergetic scalars that come from the direction of the NuMI hadron absorber, at a distance of 100 m from the detector, and decay to electron-positron pairs. We observe one candidate event, with a standard model background prediction of 1.9±0.8. We set an upper limit on the scalar-Higgs mixing angle of θ<(3.3-4.6)×10^{-4} at the 95% confidence level for scalar boson masses in the range (100-200) MeV/c^{2}. We exclude, at the 95% confidence level, the remaining model parameters required to explain the central value of a possible excess of K_{L}^{0}→π^{0}νν[over ¯] decays reported by the KOTO collaboration. We also provide a model-independent limit on a new boson X produced in K→πX decays and decaying to e^{+}e^{-}.

Treatment of cutaneous basal cell carcinoma with combined laser extirpation and methyl aminolevulinic acid: five-year success rates.

INTRODUCTION: Basal cell carcinoma is the most common cancer. Excisional surgery is associated with a high clearance rate, at the expense of significant functional and aesthetic morbidity, especially within the T-zone or for extensive lesions. We report five-year follow-up outcomes for carbon dioxide laser extirpation of cutaneous basal cell carcinoma, assisted by immediate methyl aminolevulinate photodynamic therapy and cost-benefit considerations. MATERIALS AND METHODS: Retrospective cohort database analysis of adult patients with biopsy-proven primary cutaneous basal cell carcinoma, completing five years of follow-up. Direct per-lesion cost was compared with conventional wide local excision. Patients with morphoeic basal cell carcinoma were excluded. RESULTS: Treated lesions were up to 1% total body surface area and up to 3.8mm (1.38 ± 0.695cm, mean ± standard deviation) in biopsy-proven depth. At the five-year follow-up mark, 93.6% of treated areas remained free of recurrence. Nodular basal cell carcinoma was the most common subtype (41.5%). A mean tumour depth greater than 2 ± 0.872mm was significantly associated with recurrence (Mann-Whitney, p = 0.0487). For a service delivered through the NHS at 2015 prices, we report a 43% saving, equating to a saving of £235 per basal cell carcinoma or a national annualised saving of £70 million by 2025 for the NHS. CONCLUSION: Our results suggest that CO2-assisted photodynamic therapy is non-inferior to excision but may offer better functional and cosmetic preservation at a fraction of the direct like for like cost of operative surgery. Investigation of this method by randomised controlled methodology is warranted.

Evaluation of radiotherapy education across the EU and the impact on graduates' competencies working on the linear accelerator.

INTRODUCTION: Regulation and education of the professionals administering radiotherapy treatments in the linear accelerator varies across the EU. However, how different programme characteristics affect the level of competency of these professionals has never been studied before. This study also aimed to assess which are the least and most developed competencies in radiotherapy across the EU. METHODS: An online questionnaire was distributed to academic staff teaching radiotherapy across the EU. Staff were asked to identify the characteristics of the course programmes and to classify the level of competency of graduates regarding linear accelerator tasks. RESULTS: Fifty respondents from 19 EU countries answered the questionnaire. The least developed competency theme was pharmacology followed by equipment quality assurance and management and leadership. The most developed competency was positioning and immobilisation, followed by radiotherapy treatment delivery and professional and ethical practice. Some competencies are developed at the same level across EU countries, while others vary considerably between member-states. Longer programmes, with more placements, and larger proportions of radiotherapy in the programme showed significant increase in the development of some competencies. Longer placements in skills labs was correlated with a decrease in competency. CONCLUSION: There is no harmonisation of radiotherapy eduction across the EU and the differences in programme characteristics are reflected in differences in competency levels of radiotherapy radiographers. This may hinder movement of professionals and create disparities in the level of care offered across the EU. IMPLICATIONS FOR PRACTICE: Longer programmes, with longer clinical practice and adequate proportion of radiotherapy in the course are essential to ensure that these professionals are competent at similar levels across the EU and to ensure patient safety.

First Measurement of Differential Charged Current Quasielasticlike ν_{µ}-Argon Scattering Cross Sections with the MicroBooNE Detector.

We report on the first measurement of flux-integrated single differential cross sections for charged-current (CC) muon neutrino (ν_{µ}) scattering on argon with a muon and a proton in the final state, ^{40}Ar (ν_{µ},µp)X. The measurement was carried out using the Booster Neutrino Beam at Fermi National Accelerator Laboratory and the MicroBooNE liquid argon time projection chamber detector with an exposure of 4.59×10^{19} protons on target. Events are selected to enhance the contribution of CC quasielastic (CCQE) interactions. The data are reported in terms of a total cross section as well as single differential cross sections in final state muon and proton kinematics. We measure the integrated per-nucleus CCQE-like cross section (i.e., for interactions leading to a muon, one proton, and no pions above detection threshold) of (4.93±0.76_{stat}±1.29_{sys})×10^{-38} cm^{2}, in good agreement with theoretical calculations. The single differential cross sections are also in overall good agreement with theoretical predictions, except at very forward muon scattering angles that correspond to low-momentum-transfer events.

First Measurement of Inclusive Muon Neutrino Charged Current Differential Cross Sections on Argon at E_{ν}∼0.8 GeV with the MicroBooNE Detector.

We report the first measurement of the double-differential and total muon neutrino charged current inclusive cross sections on argon at a mean neutrino energy of 0.8 GeV. Data were collected using the MicroBooNE liquid argon time projection chamber located in the Fermilab Booster neutrino beam and correspond to 1.6×10^{20} protons on target of exposure. The measured differential cross sections are presented as a function of muon momentum, using multiple Coulomb scattering as a momentum measurement technique, and the muon angle with respect to the beam direction. We compare the measured cross sections to multiple neutrino event generators and find better agreement with those containing more complete treatment of quasielastic scattering processes at low Q^{2}. The total flux integrated cross section is measured to be 0.693±0.010(stat)±0.165(syst)×10^{-38} cm^{2}.

Bicuspid and tricuspid aortic valve do not have the same ascending aorta morphology.

Bicuspid aortic valves are associated with histopathological abnormalities of the aorta. Their diameters have been measured in several studies, but the literature concerning changes in the overall anatomy of the ascending aorta is limited. We wanted to know whether the anatomy of the valve, bicuspid or tricuspid, is associated with anatomical differences. We prospectively included patients requiring aortic valve surgery. The protocol included a chest CT scan before the operation to determine the angulations and straight lengths of aortic segments 0 and 1. All of the patients underwent surgery to assess their aortic valve morphology. We included 107 patients, 25 (23%) with bicuspid diagnostic valves and 82 (77%) with tricuspid ones. Most angulations were similar between the groups. However, the angle between the ring and the plane of the top of the commissures of the semilunar cusps was lower in bicuspid than tricuspid aortic valves. The straight lengths in the aortic root did not differ significantly, but the lengths separating these planes from the BCAT plane were consistently greater in the bicuspid group. The angle between the ring plane and the patient's vertical axis was lower in the bicuspid, the plane of the ring being verticalized in this group. In conclusion, we were able to confirm significant morphological differences in addition to the diameters. However, this study does not establish causal relationships among valve morphology, ascending aortic morphology, histology, and possibly associated pathologies. An extremely large cohort will be required indicate such causal connections. Clin. Anat. 31:693-697, 2018. © 2018 Wiley Periodicals, Inc.

The Pandora multi-algorithm approach to automated pattern recognition of cosmic-ray muon and neutrino events in the MicroBooNE detector.

The development and operation of liquid-argon time-projection chambers for neutrino physics has created a need for new approaches to pattern recognition in order to fully exploit the imaging capabilities offered by this technology. Whereas the human brain can excel at identifying features in the recorded events, it is a significant challenge to develop an automated, algorithmic solution. The Pandora Software Development Kit provides functionality to aid the design and implementation of pattern-recognition algorithms. It promotes the use of a multi-algorithm approach to pattern recognition, in which individual algorithms each address a specific task in a particular topology. Many tens of algorithms then carefully build up a picture of the event and, together, provide a robust automated pattern-recognition solution. This paper describes details of the chain of over one hundred Pandora algorithms and tools used to reconstruct cosmic-ray muon and neutrino events in the MicroBooNE detector. Metrics that assess the current pattern-recognition performance are presented for simulated MicroBooNE events, using a selection of final-state event topologies.

[Late discover of a coronaro-pulmonary fistula]. / Une fistule coronaro-pulmonaire de découverte tardive.

Anomalies of the coronary arteries mainly concern a pediatric population, bringing together a wide range of defects. In adults, the evolution is linked to the hemodynamic consequences of fistula. Several therapeutic options have been proposed such as surgery or embolization. We report the case of a 55 years old patient addressed because of dyspnea secondary to aortic insufficiency. The preoperative assessment shown the coexistence of coronary abnormality corresponding to a coronaro-pulmonary fistula. This type of coronary anomaly is rarely described in the adult population, because of its consequences secondary to the closure of the foramen ovale, resulting in angina symptoms in childhood. Without treatment, mortality from this type of malformation is important (90%).

The apex of the aortic arch backshifts with aging.

BACKGROUND: Only a few studies, involving small numbers of patients, have globally assessed the curvature of the thoracic aorta but without any details concerning the location of the supra-aortic trunks. OBJECTIVES: Using CT to describe normal aortic-arch morphology and its changes with age and sex. METHODS: 344 CT scans were studied. We measured the distances from the apex to the ascending and descending aorta, the curvilinear length of the entire arch, that of the segment, including bifurcations of supra-aortic vessels, and the angle, height, and shift of the arch. RESULTS: In men, the arch was significantly longer (146.2 vs 122.8 mm; p < 0.001), higher (49.3 vs 40.1 mm, p < 0.001), and wider transversely (83.6 vs 73.3 mm; p < 0.001) than in women. The average men's arch also had a more acute angle at the apex (79.7° vs 83.7° p < 0.001). Neither morphology nor age influenced the winding angle around the mediastinum. Aging was accompanied by deflection and extension of the aortic arch, which grew more anteroposteriorly (6.1 mm/10 years in men) than vertically (2.5 mm/10 years in men), while the apex moved towards the rear of the arch. The ascending aorta was the only curvilinear length unaffected by age, whereas the supra-aortic trunks parted from each other. CONCLUSION: We believe that all these original observations could lead to a better assessment of normal aging of the aorta and guide technical choices during surgical or hybrid procedures.