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Results and prospects of the Zero Mesons/QE/2p2h-like $\nu$-A interactions at the NOvA Near Detector. Our analysis program comprises two released analyses, focusing on the hadronic and leptonic aspects of the interaction; and three upcoming analyses with improved exposure and detail on the final state.
This report documents an evaluation of 240 Pu prompt fission neutron spectra (PFNS) including Chi-Nu experimental data. This work is a FY2025 Q4 NCSP (Nuclear Criticality Safety Program) milestone and named a “strategic priority”. This evaluation is new; it differs substantially from the most recent evaluation included in the ENDF/B library, which was for ENDF/B-VII.1 and then carried over unchanged to ENDF/B-VIII.1. The key difference between ENDF/B-VIII.1 and the new evaluation is that we have, for the first time, realistic experimental 240 Pu PFNS covering a broad incident and outgoing neutron energy range.
Current and future generation neutrino oscillation experiments aim towards a high-precisionmeasurement of the oscillation parameters, which requires an unprecedented understanding ofneutrino-nucleus scattering. Charged-current quasi-elastic (CCQE) scattering is the process inwhich the neutrino produces a charged lepton and removes a single intact nucleon from the nu-cleus without producing any additional particles. For existing and forthcoming accelerator–based neutrino experiments, CCQE interactions are either the dominant process or part of the signal.MicroBooNE is the first liquid argon time projection chamber (LArTPC) commissioned as part ofthe Short Baseline Neutrino (SBN) program at Fermilab and its excellent particle reconstructioncapabilities allow the detection of neutrino interactions using exclusive final states, which will playa crucial role in the success of future kiloton LArTPC detectors such as DUNE. This talk willpresent the first measurement of exclusive νμ-Ar CCQE–like flux integrated total and differentialcross sections using single proton knock–out interactions recorded by the MicroBooNE LArTPCdetector, which has comparable acceptance to deuterium Bubble Chambers.
Semileptonic $B_{(s)}$ decays are of great phenomenological interestbecause they allow to extract CKM matrix elements or test lepton flavouruniversality. Taking advantage of existing data, we explore extractingform factors for vector final states using the narrow widthapproximation. Based on RBC/UKQCD's set of 2+1 flavour gauge fieldensembles with Shamir domain-wall fermion and Iwasaki gauge fieldaction, we study semileptonic $B_{(s)}$ decays using domain-wallfermions for light, strange and charm quarks, whereas bottom quarks aresimulated with the relativistic heavy quark (RHQ) action. Exploratoryresults for $B_s \to D_s^* \ell \nu_\ell$ are presented.
Nitrogen abundance of subgiant nu Indi from observed and computed stellar spectra of CN violet bands
The 3 nu sub 3 absorption band of C-12H4 has been measured using a high-resolution vacuum infrared spectrometer. A technique is described which allows an extension of the use of the absorption standards available at 4.7 microns to the photomultiplier region of the spectrum. The new measurements indicate a shift of about 0.18 per cm from the most recently published measurements of this band.
The rotational temperature of the 2 nu 3 methane absorptions in the solar/telluric spectrum and the methane abundance in the earth's atmosphere have been measured and are found to be 243.4 plus or minus 5.3 K and 1.137 plus or minus 0.117 cm-atm (STP) in a vertical column, respectively. The data were reduced using the results of laboratory measurements with proper allowance for the fine-structure of the methane absorption manifold and the effects of vibration-rotation interaction (which causes an enhancement of the R-branch of this band).
Presented integrated intensity data at 300 K for J multiplets between P(11) and R(11) in the nu-3 fundamental of C-12 methane are shown to be in good agreement with most previously published pertinent values. Also, line widths measured at 100 K, 130 K, 190 K, 250 K, and 300 K for R(0), R(1), and R(2) broadened by He, Ne, and Ar are presented, and the line-width temperature dependence is discussed for the three cases of broadening.
Measurements of the absolute intensity and integrated band absorption have been performed for the nu sub 9 fundamental band of ethane. The intensity is found to be about 34 per sq cm per atm at STP, and this is significantly higher than previous estimates. It is shown that a Gaussian profile provides an empirical representation of the apparent spectral absorption coefficient. Employing this empirical profile, a simple expression is derived for the integrated band absorption, which is in excellent agreement with experimental values. The band model is then employed to investigate the possible role of ethane as a source of thermal infrared opacity within the atmospheres of Jupiter and Saturn, and to interpret qualitatively observed brightness temperatures for Saturn.
Mathematical procedures are developed which can provide an exact solution for the structure of synchronously rotating close binaries built on the polytropic model with nu equal to 3. Results are discussed for separations of centers of 10.0, 4.0, 3.0, and 2.8 solar radii. For the present discussion, both components are assumed to have the solar mass and, in the zeroth approximation, the solar radius. The present results are compared with those obtained by Chandrasekhar (1933) using first-order perturbation theory.
Using parameters recently measured in the laboratory, the shapes of manifolds belonging to the R-branch of Saturn's 3 nu 3 CH4 band were analyzed in terms of a homogeneous scattering model of Saturn's atmosphere, and the results were compared with those of an earlier analysis in terms of a reflecting-layer model. The resulting effective pressure is an order of magnitude smaller than for the reflecting-layer analysis, and the C/H ratio is an order of magnitude higher than the solar value. The overall fit of the theoretical profiles to the observed manifold shapes is distinctly worse, especially for R(7). Scattering evidently plays only a minor role in the formation of this band along Saturn's south-central meridian.
A complete atlas of the 5 nu-1 absorption band of NH3 is presented together with measurements of the total band intensity, line intensities, and self-broadening coefficients. The spectrum, which is displayed in the interval from 6418 to 6550 A, was obtained photoelectrically at a pressure of 0.061 atm, and many more lines were seen in this spectrum than in a previous one obtained at a pressure of 0.39 atm. The band intensity is used to derive the NH3 abundance in the atmospheres of Jupiter and Saturn, and the abundances in a single vertical path are found to be about 10 m amagat for Jupiter and 2 m amagat for Saturn. These results are shown to be in agreement with previous results obtained from higher resolution photographic spectra.
Observations of the nu-2 band of NH3 in the Jovian atmosphere have been made at resolutions varying from 4 per cm to 0.15 per cm. The observations have been interpreted by computation of synthetic atmospheric spectra. Derived atmospheric parameters include a pressure of 0.5 atm at 145 K and a minimum temperature of 118 K.
Observed profiles of the R branch of Saturn's CH4 3 nu (3) band are compared with synthetic profiles computed from inhomogeneous models which are consistent with Saturn's H2 quadrupole-line equivalent widths. A C/H ratio approximately three times the solar value and a CH4 abundance of about 100 m am are found. Scattering plays a significant role in the formation of manifold profiles below a depth where the H2 abundance is 20-30 km am.
The absolute integrated intensity of the IR vibration-rotation nu-1 SO2 band was measured using the linear portion of the curve of growth. Infrared spectroscopic-absorption cell measurements were performed on sulfur dioxide at partial pressures less than 0.15 torr with nitrogen added to give a total pressure of 705 torr, the path length being 4 mm. The absolute integrated intensity was determined to be 112.0 plus or minus 2.6/cm/sq (atm cm) at 296 K at the 95% confidence level.
The absorption strengths of the Q-branch manifolds of the nu-1 band of methyl chloride were measured. The results were used to deduce the band strength, which is 32.1 plus or minus 2.9 per sq cm-atm at 297 K. The P-branch absorptions were investigated to assess the possibility of determining a vibration-rotation factor for the band. This factor is approximately 1.026.
Comparison of infrared solar spectra in the 750 to 950 kayser region obtained during sunrise and sunset shows that a number of features due to the nu-2 NH3 band are present on the sunset spectra but are indicated by only a trace on the sunrise spectra. The sunset path shows approximately 0.007 atm-cm NH3, and the reason for the discrepancy between sunrise and sunset spectra is not known. The ground-based measurements at Denver were obtained with a 0.06 kayser resolution.
The computer program NUED for analyzing potential flow about arbitrary three dimensional lifting bodies using the panel method was modified to use vector operations and run on the STAR-100 computer. A high speed of computation and ability to approximate the body surface with a large number of panels are characteristics of NUEDV. The new program shows that vector operations can be readily implemented in programs of this type to increase the computational speed on the STAR-100 computer. The virtual memory architecture of the STAR-100 facilitates the use of large numbers of panels to approximate the body surface.