Using an 185-kg NaITl array, COHERENT has measured the inclusive electron-neutrino chargedcurrent cross section on 127I with pion decay-at-rest neutrinos produced by the Spallation Neutron Source at ...Oak Ridge National Laboratory. Iodine is one the heaviest targets for which low-energy (≤ 50 MeV) inelastic neutrino-nucleus processes have been measured, and this is the first measurement of its inclusive cross section. After a five-year detector exposure, COHERENT reports a flux-averaged cross section for electron neutrinos of ${9.2}_{—1.8}^{+2.1}$ × 10—40 cm2. This corresponds to a value that is ~41% lower than predicted using the MARLEY event generator with a measured Gamow-Teller strength distribution. In addition, the observed visible spectrum from charged-current scattering on 127I has been measured between 10 and 55 MeV, and the exclusive zero-neutron and one-or-more-neutron emission cross sections are measured to be ${5.2}_{—3.1}^{+3.4}$ × 10—40 and ${2.2}_{—2.2}^{+3.5}$ × 10—40 cm2, respectively.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
We have measured proton and deuteron virtual photon-nucleon asymmetries A{sup p}{sub 2} and A{sup d}{sub 2} and structure functions g{sup p}{sub 2} and g{sup d}{sub 2} over the range 0.03 < x < 0.8 ...and 1.3 < Q{sup 2} < 10 (GeV/c){sup 2} by inelastically scattering polarized electrons off polarized ammonia targets. Results for A{sub 2} are significantly smaller than the positivity limit (sqrt)R for both targets. Within experimental precision the g{sub 2} data are well described by the twist-2 contribution, g{sup ww}{sub 2}. Twist-3 matrix elements have been extracted and are compared to theoretical predictions.
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We consider the potential for a 10 kg undoped cryogenic CsI detector operating at the Spallation Neutron Source to measure coherent elastic neutrino-nucleus scattering and its sensitivity to discover ...new physics beyond the standard model (BSM). Through a combination of increased event rate, lower threshold, and good timing resolution, such a detector would significantly improve on past measurements. We considered tests of several BSM scenarios such as neutrino nonstandard interactions and accelerator-produced dark matter. This detector’s performance was also studied for relevant questions in nuclear physics and neutrino astronomy, namely the weak charge distribution of Cs and I nuclei and detection of neutrinos from a core-collapse supernova. Published by the American Physical Society 2024
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We present a next-to-leading order perturbative QCD analysis of world data on the spin dependent structure functions
g
1
p
,
g
1
n
, and
g
1
d
, including the new experimental information on the
Q
2 ...dependence of
g
1
n
. Careful attention is paid to the experimental and theoretical uncertainties. The data constrain the first moments of the polarized valence quark distributions, but only qualitatively constrain the polarized sea quark and gluon distributions. The NLO results are used to determine the
Q
2 dependence of the ratio
g
1
F
1
and evolve the experimental data to a constant
Q
2 = 5 GeV
2. We determine the first moments of the polarized structure functions of the proton and neutron and find agreement with the Bjorken sum rule.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The Near Detector for the MINOS Experiment at Fermilab is composed of alternating planes of scintillator strips and steel plates, and is read out with 64-channel, multi-anode photomultiplier tubes. ...The instrumentation uses a custom integrated circuit designed at Fermilab for the front end analog processing, called the QIE. The system can measure single photoelectrons to high precision with a dynamic range of 16 bits. The electronics operates in two modes. It records all events that occur during the 10 /spl mu/s "fast spill" of the beam from the Fermilab Main Injector at a rate of 53 MHz, using a gate from the beamline controls to force data acquisition. The system can also acquire data from cosmic rays that pass through the detector for calibration. In this case, dynode signals from the photomultipliers are used as the trigger, causing digitization and readout of the associated channels. Zero suppression and normalization are done in the front end electronics. The system is "triggerless" in that there is no global hardware trigger. Instead, each event is tagged with a "timestamp", which is used in postprocessing to reconstruct events and discard noise hits. The system of 10,000 channels is now built and installed, and operational at Fermilab. The components of the system are described and preliminary system performance is reported.
Abstract
We present results of several measurements of CsINa
scintillation response to 3–60 keV energy nuclear recoils
performed by the COHERENT collaboration using tagged neutron elastic
scattering ...experiments and an endpoint technique. Earlier results,
used to estimate the coherent elastic neutrino-nucleus scattering
(CEvNS) event rate for the first observation of this process
achieved by COHERENT at the Spallation Neutron Source (SNS), have
been reassessed. We discuss corrections for the identified
systematic effects and update the respective uncertainty values. The
impact of updated results on future precision tests of CEvNS is
estimated. We scrutinize potential systematic effects that could
affect each measurement. In particular we confirm the response of
the H11934-200 Hamamatsu photomultiplier tube (PMT) used for the
measurements presented in this study to be linear in the relevant
signal scale region.
In the pharmaceutical industry, new drugs are tested to find appropriate compounds for therapeutic purposes for contemporary diseases. Unfortunately, novel compounds emerge at expensive prices and ...current target evaluation processes have limited throughput, thus leading to an increase of cost and time for drug development. This work shows the development of the novel inkjet-based deposition method for assembling a miniature drug-screening platform, which can realistically and inexpensively evaluate biochemical reactions in a picoliter-scale volume at a high speed rate. As proof of concept, applying a modified Hewlett Packard model 5360 compact disc printer, green fluorescent protein expressing Escherichia coli cells along with alginate gel solution have been arrayed on a coverslip chip under a repeatable volume of 180% ± 26% picoliters per droplet; subsequently, different antibiotic droplets were patterned on the spots of cells to evaluate the inhibition of bacteria for antibiotic screening. The proposed platform was compared to the current screening process, validating its effectiveness. The viability and basic function of the printed cells were evaluated, resulting in cell viability above 98% and insignificant or no DNA damage to human kidney cells transfected. Based on the reduction of investment and compound volume used by this platform, this technique has the potential to improve the actual drug discovery process at its target evaluation stage.
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