First Constraints on Heavy QCD Axions with a Liquid Argon Time Projection Chamber Using the ArgoNeuT Experiment.

We present the results of a search for heavy QCD axions performed by the ArgoNeuT experiment at Fermilab. We search for heavy axions produced in the NuMI neutrino beam target and absorber decaying into dimuon pairs, which can be identified using the unique capabilities of ArgoNeuT and the MINOS near detector. This decay channel is motivated by a broad class of heavy QCD axion models that address the strong CP and axion quality problems with axion masses above the dimuon threshold. We obtain new constraints at a 95% confidence level for heavy axions in the previously unexplored mass range of 0.2-0.9 GeV, for axion decay constants around tens of TeV.

Scintillation light detection in the 6-m drift-length ProtoDUNE Dual Phase liquid argon TPC.

DUNE is a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon decay searches. ProtoDUNE Dual Phase (DP) is a 6  ×  6  ×  6 m 3 liquid argon time-projection-chamber (LArTPC) that recorded cosmic-muon data at the CERN Neutrino Platform in 2019-2020 as a prototype of the DUNE Far Detector. Charged particles propagating through the LArTPC produce ionization and scintillation light. The scintillation light signal in these detectors can provide the trigger for non-beam events. In addition, it adds precise timing capabilities and improves the calorimetry measurements. In ProtoDUNE-DP, scintillation and electroluminescence light produced by cosmic muons in the LArTPC is collected by photomultiplier tubes placed up to 7 m away from the ionizing track. In this paper, the ProtoDUNE-DP photon detection system performance is evaluated with a particular focus on the different wavelength shifters, such as PEN and TPB, and the use of Xe-doped LAr, considering its future use in giant LArTPCs. The scintillation light production and propagation processes are analyzed and a comparison of simulation to data is performed, improving understanding of the liquid argon properties.

Prospects for beyond the Standard Model physics searches at the Deep Underground Neutrino Experiment: DUNE Collaboration.

The Deep Underground Neutrino Experiment (DUNE) will be a powerful tool for a variety of physics topics. The high-intensity proton beams provide a large neutrino flux, sampled by a near detector system consisting of a combination of capable precision detectors, and by the massive far detector system located deep underground. This configuration sets up DUNE as a machine for discovery, as it enables opportunities not only to perform precision neutrino measurements that may uncover deviations from the present three-flavor mixing paradigm, but also to discover new particles and unveil new interactions and symmetries beyond those predicted in the Standard Model (SM). Of the many potential beyond the Standard Model (BSM) topics DUNE will probe, this paper presents a selection of studies quantifying DUNE's sensitivities to sterile neutrino mixing, heavy neutral leptons, non-standard interactions, CPT symmetry violation, Lorentz invariance violation, neutrino trident production, dark matter from both beam induced and cosmogenic sources, baryon number violation, and other new physics topics that complement those at high-energy colliders and significantly extend the present reach.

New Constraints on Tau-Coupled Heavy Neutral Leptons with Masses m_{N}=280-970 MeV.

A search for heavy neutral leptons has been performed with the ArgoNeuT detector exposed to the NuMI neutrino beam at Fermilab. We search for the decay signature N→νµ^{+}µ^{-}, considering decays occurring both inside ArgoNeuT and in the upstream cavern. In the data, corresponding to an exposure to 1.25×10^{20} POT, zero passing events are observed consistent with the expected background. This measurement leads to a new constraint at 90% confidence level on the mixing angle |U_{τN}|^{2} of tau-coupled Dirac heavy neutral leptons with masses m_{N}=280-970 MeV, assuming |U_{eN}|^{2}=|U_{µN}|^{2}=0.

Cosmic Ray Background Removal With Deep Neural Networks in SBND.

In liquid argon time projection chambers exposed to neutrino beams and running on or near surface levels, cosmic muons, and other cosmic particles are incident on the detectors while a single neutrino-induced event is being recorded. In practice, this means that data from surface liquid argon time projection chambers will be dominated by cosmic particles, both as a source of event triggers and as the majority of the particle count in true neutrino-triggered events. In this work, we demonstrate a novel application of deep learning techniques to remove these background particles by applying deep learning on full detector images from the SBND detector, the near detector in the Fermilab Short-Baseline Neutrino Program. We use this technique to identify, on a pixel-by-pixel level, whether recorded activity originated from cosmic particles or neutrino interactions.

Improved Limits on Millicharged Particles Using the ArgoNeuT Experiment at Fermilab.

A search for millicharged particles, a simple extension of the standard model, has been performed with the ArgoNeuT detector exposed to the Neutrinos at the Main Injector beam at Fermilab. The ArgoNeuT liquid argon time projection chamber detector enables a search for millicharged particles through the detection of visible electron recoils. We search for an event signature with two soft hits (MeV-scale energy depositions) aligned with the upstream target. For an exposure of the detector of 1.0×10^{20} protons on target, one candidate event has been observed, compatible with the expected background. This search is sensitive to millicharged particles with charges between 10^{-3}e and 10^{-1}e and with masses in the range from 0.1 to 3 GeV. This measurement provides leading constraints on millicharged particles in this large unexplored parameter space region.

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.

First measurement of neutrino and antineutrino coherent charged pion production on argon.

We report on the first cross section measurements for charged current coherent pion production by neutrinos and antineutrinos on argon. These measurements are performed using the ArgoNeuT detector exposed to the NuMI beam at Fermilab. The cross sections are measured to be 2.6(-1.0)(+1.2)(stat)(-0.4)(+0.3)(syst)×10(-38) cm(2)/Ar for neutrinos at a mean energy of 9.6 GeV and 5.5(-2.1)(+2.6)(stat)(-0.7)(+0.6)(syst)×10(-39) cm(2)/Ar for antineutrinos at a mean energy of 3.6 GeV.

Effects of phacoemulsification time on the corneal endothelium using phacofracture and phaco chop techniques.

PURPOSE: To quantitatively assess early postoperative endothelial damage caused by two phacoemulsification techniques and to ascertain the effect of differences in phacoemulsification time. SETTING: Department of Ophthalmology, Umberto Hospital, Lugo, Italy. METHODS: This prospective study evaluated 100 patients who had phacoemulsification using one of two techniques: phaco chop (n = 50) or four-quadrant, divide and conquer phacofracture (n = 50). The endothelium of both groups was analyzed preoperatively and 8 weeks postoperatively by specular microscopy. RESULTS: Phaco chop led to significantly shorter phacoemulsification time and less endothelial damage. Mean equivalent phacoemulsification time was 25.53 seconds +/- 11.26 (SD) in the phaco chop group and 87.26 +/- 48.03 seconds in the phacofracture group. Endothelial cell loss was 4.72 +/- 1.2% and 13.80 +/- 4.3%, respectively. CONCLUSION: The phaco chop technique led to shorter phacoemulsification time and less endothelial cell loss.

Orbital cavernous angiomas: surgical experience on a series of 13 cases.

Cavernous angiomas of the orbit are benign vascular growths, commonly occurring in adults and usually causing a slowly progressive proptosis from their mass effect. These lesions have behavioural and radiological findings different from those of brain cavernous angiomas, probably due to their particular origin and structure. The authors present a surgical series of 13 patients with orbital cavernous angiomas. Complete excision of lesions, with histological diagnosis, was obtained in all the 13 cases. Results were good in 10 patients, while 2 remained clinically unchanged and another one showed acute visual deterioration after a period of postoperative clinical stabilization. The main clinical and radiological characteristics of orbital cavernous angiomas are analyzed, together with their surgical management.

Intracranial and orbital cavernous angiomas: a review of 74 surgical cases.

We present a surgical series of 74 patients (30 males and 44 females) with pathologically verified cavernous angiomas of the intracranial and orbital compartments. Patients were admitted between 1975 and 1991; six had a family history of cerebral cavernomas, and two had multiple (two) lesions. The 76 malformations were located as follows: 57 were in the cerebral hemispheres, four in the supratentorial ventricles, one was in the middle cranial fossa, two were in the brain stem, five in the cerebellum and seven in the orbits. Seizures and focal neurological deficits, and decrease of visual acuity with exophthalmus, were the main clinical signs observed in patients with intracranial and orbital cavernomas, respectively. Sixteen patients (21.6%) had a clinically significant haemorrhage attributable to the cavernous angioma. A number of these vascular malformations were misdiagnosed by computed tomography. In the last 10 years magnetic resonance imaging has been the most sensitive method for detecting these lesions. Seventy-four of the 76 diagnosed cavernomas were treated surgically: a complete excision was obtained in 68 patients; in two patients with multiple lesions only those causing symptoms were removed. Surgery for the 10 deep lesions was aided considerably by stereotactic localization. Two patients died in the immediate postoperative course. The overall outcome was good in 66 of the 72 remaining patients, resulting in improved seizure control or lessened neurological deficit.