The MiniBooNE experiment at Fermilab reports a total excess of 638.0 ± 52.1 (stat .) ± 122.2 (syst.) electronlike events from a data sample corresponding to 18.75 × 10 20 protons-on-target in ...neutrino mode, which is a 46% increase in the data sample with respect to previously published results and 11.27 × 10 20 protons-on-target in antineutrino mode. The overall significance of the excess, 4.8σ, is limited by systematic uncertainties, assumed to be Gaussian, as the statistical significance of the excess is 12.2σ. The additional statistics allow several studies to address questions on the source of the excess. First, we provide two-dimensional plots in visible energy and the cosine of the angle of the outgoing lepton, which can provide valuable input to models for the event excess. Second, we test whether the excess may arise from photons that enter the detector from external events or photons exiting the detector from π 0 decays in two model independent ways. Beam timing information shows that almost all of the excess is in time with neutrinos that interact in the detector. The radius distribution shows that the excess is distributed throughout the volume, while tighter cuts on the fiducial volume increase the significance of the excess. The data likelihood ratio disfavors models that explain the event excess due to entering or exiting photons.
A
bstract
This article reports global fits of short-baseline neutrino data to oscillation models involving light sterile neutrinos. In the commonly-used 3+1 plane wave model, there is a well-known ...4.9
σ
tension between data sets sensitive to appearance versus disappearance of neutrinos. We find that models that damp the oscillation prediction for the reactor data sets, especially at low energy, substantially improve the fits and reduce the tension. We consider two such scenarios. The first scenario introduces the quantum mechanical wavepacket effect that accounts for the source size in reactor experiments into the 3+1 model. We find that inclusion of the wavepacket effect greatly improves the overall fit compared to a three-neutrino model by ∆
χ
2
/
dof = 61
.
1
/
4 (7
.
1
σ
improvement) with best-fit ∆
m
2
= 1
.
4 eV
2
and wavepacket length of 67 fm. The internal tension is reduced to 3.4
σ
. If reactor-data only is fit, then the wavepacket preferred length is 91 fm (
>
20 fm at 99% CL). The second model introduces oscillations involving sterile flavor and allows the decay of the heaviest, mostly sterile mass state,
ν
4
. This model introduces a damping term similar to the wavepacket effect, but across all experiments. Compared to a three-neutrino fit, this has a ∆
χ
2
/
dof = 60
.
6
/
4 (7
σ
improvement) with preferred ∆
m
2
= 1
.
4 eV
2
and decay Γ = 0
.
35 eV. The internal tension is reduced to 3.7
σ
.
For many years, the reactor event rates have been observed to have structure that deviates from prediction. Community discussion has focused on an excess compared to prediction observed at 5 MeV; however, other deviations are apparent. This structure has
L
dependence that is well-fit by the damped models. Before assuming this points to new physics, we urge closer examination of systematic effects that could lead to this
L
dependence.
Single ventricle physiology is a rare form of congenital heart disease and was, historically, a uniformly lethal condition. However, the atriopulmonary Fontan operation, and its successive ...iterations, the lateral tunnel and extracardiac conduit Fontan, became the fundamental approach to treating single ventricle heart disease. Over time, dysrhythmias are some of the most common complications with Fontan physiology, compounding morbidity and mortality. Atrial arrhythmias are prevalent in the Fontan population and occur in about 15–60% of patients with Fontan palliation, increasingly with age. Diagnosing atrial arrhythmias in patients with Fontan palliation may be challenging because of low voltage amplitudes arising from myopathic atrial tissue making it difficult to clearly assess atrial depolarization on surface electrocardiograms (ECG), vague symptoms not suggestive of tachyarrhythmia, or atrial arrhythmia with ventricular rates below 100 beats per minute. Intra-atrial reentrant tachycardia (IART) is the most common type of supraventricular tachycardia in adults with Fontan palliation. Acute management of atrial arrhythmias in patients with Fontan palliation involves prompt assessment of a patient’s hemodynamic stability, anticoagulation and thrombosis risk, systemic ventricular function, and risk of sedation or anesthesia if needed. Long-term management of atrial arrhythmias is often multifactorial and may include long-term anti-arrhythmic therapy, permanent pacing, and ablation. The best approach for the management of atrial arrhythmias in adults with Fontan palliation is patient-specific and involves collaboration between congenital electrophysiologists, adult congenital cardiologists, and the patient.
Field-applied liquid animal manure (slurry) is a significant source of ammonia (NH3) emission, which is harmful to the environment and human health. To evaluate mitigation options, reliable emission ...measurement methods are needed. A new system of dynamic flux chambers (DFCs) with high-temporal-resolution online measurements was developed. The system was investigated in silico with computational fluid dynamics and tested using three respective field trials, with each trial assessing the variability in the measured emission after application with trailing hose at different scales: manual (handheld) application, a 3 m experimental slurry boom, and a 30 m farm-scale commercial slurry boom. For the experiments with machine application, parallel NH3 emission measurements were made using an inverse dispersion modeling method (backward Lagrangian stochastic, bLS, modeling). The lowest coefficient of variation among replicate DFC measurements was obtained with manual application (5 %), followed by the 3 m slurry boom (14 %), and lastly the 30 m slurry boom (20 %). Conditions in DFCs resulted in a consistently higher NH3 flux than that measured with the inverse dispersion technique, but both methods showed a similar emission reduction by injection compared with the trailing hose: 89 % by DFC and 97 % by bLS modeling. The new measurement system facilitates NH3 emission measurement with replication after both manual and farm-scale slurry application with relatively high precision.
We report the first results of a search for leptophobic dark matter (DM) from the Coherent–CAPTAIN-Mills (CCM) liquid argon (LAr) detector. An engineering run with 120 photomultiplier tubes (PMTs) ...and 17.9 × 1020 protons on target (POT) was performed in fall 2019 to study the characteristics of the CCM detector. The operation of this 10-ton detector was strictly light based with a threshold of 50 keV and used coherent elastic scattering off argon nuclei to detect DM. Despite only 1.5 months of accumulated luminosity, contaminated LAr, and nonoptimized shielding, CCM’s first engineering run has already achieved sensitivity to previously unexplored parameter space of light dark matter models with a baryonic vector portal. With an expected background of 115 005 events, we observe 115 005 + 16.5 events which is compatible with background expectations. For a benchmark mediator-to-DM mass ratio of mVB=mχ = 2.1, DM masses within the range 9 MeV ≲ mχ ≲ 50 MeV are excluded at 90% C. L. in the leptophobic model after applying the Feldman-Cousins test statistic. CCM’s upgraded run with 200 PMTs, filtered LAr, improved shielding, and 10 times more POT will be able to exclude the remaining thermal relic density parameter space of this model, as well as probe new parameter space of other leptophobic DM models.
Background The objective of this international multicenter study was to investigate both early and late outcomes of cardiac resynchronization therapy (CRT) in patients with a systemic right ventricle ...(SRV) and to identify predictors for congestive heart failure readmissions and mortality. Methods and Results This retrospective international multicenter study included 13 centers. The study population comprised 80 adult patients with SRV (48.9% women) with a mean age of 45±14 (range, 18-77) years at initiation of CRT. Median follow-up time was 4.1 (25th-75th percentile, 1.3-8.3) years. Underlying congenital heart disease consisted of congenitally corrected transposition of the great arteries and dextro-transposition of the great arteries in 63 (78.8%) and 17 (21.3%) patients, respectively. CRT resulted in significant improvement in functional class (before CRT: III, 25th-75th percentile, II-III; after CRT: II, 25th-75th percentile, II-III;
=0.005) and QRS duration (before CRT: 176±27; after CRT: 150±24 milliseconds;
=0.003) in patients with pre-CRT ventricular pacing who underwent an upgrade to a CRT device (n=49). These improvements persisted during long-term follow-up with a marginal but significant increase in SRV function (before CRT; 30%, 25th-75th percentile, 25-35; after CRT: 31%, 25th-75th percentile, 21-38;
=0.049). In contrast, no beneficial change in the above-mentioned variables was observed in patients who underwent de novo CRT (n=31). A quarter of all patients were readmitted for heart failure during follow-up, and mortality at latest follow-up was 21.3%. Conclusions This international experience with CRT in patients with an SRV demonstrated that CRT in selected patients with SRV dysfunction and pacing-induced dyssynchrony yielded consistent improvement in QRS duration and New York Heart Association functional status, with a marginal increase in SRV function.
One of the most important doctrines a constitutional court must consider when exercising judicial review is severability. If a court decides that a statutory provision is unconstitutional, it must ...also decide whether that provision may be severed from the statute to allow the remainder to carry the full force of law. While the use of severability by constitutional courts has generated substantial controversy among legal scholars, there has been scant empirical analysis evaluating their claims of how courts employ severability doctrine. Relying on both legal and social science scholarship, I craft a series of hypotheses about how courts use severability. I test these hypotheses on the U.S. Supreme Court’s constitutional decisions on important federal statutes over the post-war period. The analysis shows that both political and legal considerations influence the Court’s severability doctrine, simultaneously fueling and allaying the criticisms of the legal community.
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