20 research outputs found
COHERENT Collaboration data release from the measurements of CsI[Na] response to nuclear recoils
Description of the data release 10.13139/OLCF/1969085
(https://doi.ccs.ornl.gov/ui/doi/426) from the measurements of the CsI[Na]
response to low energy nuclear recoils by the COHERENT collaboration. The
release corresponds to the results published in "D. Akimov et al 2022 JINST 17
P10034". We share the data in the form of raw ADC waveforms, provide benchmark
values, and share plots to enhance the transparency and reproducibility of our
results. This document describes the contents of the data release as well as
guidance on the use of the data
Monitoring the SNS basement neutron background with the MARS detector
We present the analysis and results of the first dataset collected with the
MARS neutron detector deployed at the Oak Ridge National Laboratory Spallation
Neutron Source (SNS) for the purpose of monitoring and characterizing the
beam-related neutron (BRN) background for the COHERENT collaboration. MARS was
positioned next to the COH-CsI coherent elastic neutrino-nucleus scattering
detector in the SNS basement corridor. This is the basement location of closest
proximity to the SNS target and thus, of highest neutrino flux, but it is also
well shielded from the BRN flux by infill concrete and gravel. These data show
the detector registered roughly one BRN per day. Using MARS' measured detection
efficiency, the incoming BRN flux is estimated to be
for neutron energies
above ~MeV and up to a few tens of MeV. We compare our results with
previous BRN measurements in the SNS basement corridor reported by other
neutron detectors.Comment: Submitted to JINS
First Probe of Sub-GeV Dark Matter Beyond the Cosmological Expectation with the COHERENT CsI Detector at the SNS
The COHERENT collaboration searched for scalar dark matter particles produced
at the Spallation Neutron Source with masses between 1 and 220~MeV/c using
a CsI[Na] scintillation detector sensitive to nuclear recoils above
9~keV. No evidence for dark matter is found and we thus place
limits on allowed parameter space. With this low-threshold detector, we are
sensitive to coherent elastic scattering between dark matter and nuclei. The
cross section for this process is orders of magnitude higher than for other
processes historically used for accelerator-based direct-detection searches so
that our small, 14.6~kg detector significantly improves on past constraints. At
peak sensitivity, we reject the flux consistent with the cosmologically
observed dark-matter concentration for all coupling constants ,
assuming a scalar dark-matter particle. We also calculate the sensitivity of
future COHERENT detectors to dark-matter signals which will ambitiously test
multiple dark-matter spin scenarios
Measurement of scintillation response of CsI[Na] to low-energy nuclear recoils by COHERENT
We present results of several measurements of CsI[Na] 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.Comment: The version accepted by JINST. The changes made as a result of the
peer review process: 1. Section 8 "Global CsI[Na] QF data fit" is expanded.
The main fit result and its uncertainty is NOT CHANGED. An alternative fit is
now shown in Figure 14, Figure 15 is added to further validate the
assumptions in the main fit. 2. The Appendix B is restructured for clarit
Measurement of Pb(,X) production with a stopped-pion neutrino source
Using neutrinos produced at the Spallation Neutron Source (SNS) at Oak Ridge
National Laboratory (ORNL), the COHERENT collaboration has studied the
Pb(,X) process with a lead neutrino-induced-neutron (NIN) detector.
Data from this detector are fit jointly with previously collected COHERENT data
on this process. A combined analysis of the two datasets yields a cross section
that is times that predicted by the MARLEY event
generator using experimentally-measured Gamow-Teller strength distributions,
consistent with no NIN events at 1.8. This is the first inelastic
neutrino-nucleus process COHERENT has studied, among several planned exploiting
the high flux of low-energy neutrinos produced at the SNS.Comment: 11 pages, 9 figures, version accepted by Phys. Rev.
Beyond compliance: project on an integrated systems approach for pest risk management in South East Asia
The Beyond Compliance project, which began in July 2011 with funding from the Standards and Trade Development Facility for 2 years, aims to enhance competency and confidence in the South East Asian sub-region by applying a Systems Approach for pest risk management. The Systems Approach involves the use of integrated measures, at least two of which are independent, that cumulatively reduce the risk of introducing exotic pests through trade. Although useful in circumstances where single measures are inappropriate or unavailable, the Systems Approach is inherently more complicated than single-measure approaches, which may inhibit its uptake. The project methodology is to take prototype decision-support tools, such as Control Point-Bayesian Networks (CP-BN), developed in recent plant health initiatives in other regions, including the European PRATIQUE project, and to refine them within this sub-regional context. Case studies of high-priority potential agricultural trade will be conducted by National Plant Protection Organizations of participating South East Asian countries in trials of the tools, before further modifications. Longer term outcomes may include: more robust pest risk management in the region (for exports and imports); greater inclusion of stakeholders in development of pest risk management plans; increased confidence in trade negotiations; and new opportunities for trade