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The UCNA experiment was designed to measure the neutron β-asymmetry parameter A0 using polarized ultracold neutrons (UCN). UCN produced via downscattering in solid deuterium were polarized via transport through a 7 T magnetic field, and then directed to a 1 T solenoidal electron spectrometer, where the decay electrons were detected in electron detector packages located on the two ends of the spectrometer. A value for A0 was then extracted from the asymmetry in the numbers of counts in the two detector packages. We summarize all of the results from the UCNA experiment, obtained during run periods in 2007, 2008–2009, 2010, and 2011–2013, which ultimately culminated in a 0.67% precision result for A₀.

It has been proposed recently that a previously unobserved neutron decay branch to a dark matter particle ($\chi$) could account for the discrepancy in the neutron lifetime observed in experiments that use two different measurement techniques. One of the possible final states discussed includes a single $\chi$ along with an $e^{+}e^{-}$ pair. We use data from the UCNA (Ultracold Neutron Asymmetry) experiment to set limits on this decay channel. Coincident electron-like events are detected with $\sim 4\pi$ acceptance using a pair of detectors that observe a volume of stored Ultracold Neutrons (UCNs). The summed kinetic energy ($E_{e^{+}e^{-}}$) from such events is used to set limits, as a function of the $\chi$ mass, on the branching fraction for this decay channel. For $\chi$ masses consistent with resolving the neutron lifetime discrepancy, we exclude this as the dominant dark matter decay channel at $\gg~5\sigma$ level for $100~\text{keV} < E_{e^{+}e^{-}} < 644~\text{keV}$. If the $\chi+e^{+}e^{-}$ final state is not the only one, we set limits on its branching fraction of $< 10^{-4}$ for the above $E_{e^{+}e^{-}}$ range at $> 90\%$ confidence level., Comment: 5 pages, 5 figures

The primary objective of this Project was to provide an understanding of UK produced biomass properties, how these vary and what causes this variability. This report provides an overview of the first phase (2015/16) of the Characterisation of Feedstocks project, excluding the extension work (reported in Deliverables D12 Report and D13 Whole Project Executive Report). The report starts with a summary of the key findings from the four studies carried out during 2015 and 2016. This is followed by an introduction to the context of the Project, including background, rationale and objectives; a description of the project approach, including the parameters investigated;The hypotheses tested; and the experimental protocols.The report then provides a summary of the two main areas of study, the results obtained and the statistical analyses used. An initial comparison of the results with those in the principal International database of biomass properties is discussed to put the results into context.The results and findings from the third and fourth areas of study are presented: comparison of variation within individual fields with those observed between sites, and the effect of pelletisation on Miscanthus properties. Commentary on the relative costs of establishment and production for the different feedstocks are provided. Finally the implications of, and recommendations to be drawn from the study are discussed

The primary objective of this 2015/16/17 Project was to provide an understanding of UK produced biomass properties, how these vary and what causes this variability. This document contains the Appendices to the Final Report from the second Phase (2016/17) of the Characterisation of Feedstocks (CofF) project, Deliverable D12. This deliverable (D12) is one of three to be provided under the second phase (2016/17) of the Characterisation of Feedstocks Project. It is supported by the Excel dataset (D11). A synthesis and summary of the findings from the whole project, Phases 1 plus 2, is provided separately (Deliverable D13).The purpose of this deliverable D12 is to reportthe findings from the 2016/17 investigations into the impact of harvest time on the properties of UK produced Short Rotation Coppice (SRC) willow and Miscanthus;the impact of variety on UK produced SRC willow properties, and;the impact of four different types of commonly used storage types over time on UK produced Miscanthus properties.

The primary objective of this 2015/16/17 Project was to provide an understanding of UK produced biomass properties, how these vary and what causes this variability. This slide set was presented on 16th March 2017 to ETI by theForest Research led team, and covers the findings from the whole of the Characterisation of Feedstocks Project.

The ETI appointed North Energy Associates (NEA) to lead a new Carbon Life Cycle Assessment (LCA) Evidence Analysis project in its Bioenergy Programme. LCAs are used to understand the greenhouse gas emissions associated with bioenergy from across the supply chain, from feedstock production to energy production. Several different methodologies can be used in LCAs and this ETI project assessed the strengths and weaknesses associated with applying these methodologies to bioenergy value chains. It also reviewed sources of data for LCAs and produced a compendium of the best and most reliable data across different UK-relevant bioenergy feedstocks and value chains. This compendium has formed the basis of a series of carbon balance calculations across a range of bioenergy value chains so that emissions from different feedstocks can be compared.This report documents the outcomes of Work Package 2 of this project which has the main objectives of analysing previous relevant LCA studies by providinga critique of the robustness of the evidence base based on both data and methodologies used;a measure of certainty behind the data reviewed; anddetails of the confidence the reviewer may have in interpreting the data.As a basis for this, a concise summary of the context of bioenergy LCA studies has been produced to cover the types of questions that, typically, they attempt to answer and the appropriate methodologies that they should use to do this, and to highlight some of the areas where there are conflicting views as to the appropriate approach.

Appendices to the final report on investigations into the effect of harvest time and variety on willow SRC and the effect of harvest time and storage method on Miscanthus quality Deliverable Context and Key Content.

The primary objective of this Project was to provide an understanding of UK produced biomass properties, how these vary and what causes this variability. This deliverable is provided under the second phase (2016/17) of the Characterisation of Feedstocks Project. This report is a summary of the findings from the whole project, it complements the Final Reports from the first and second phases (D6 and D12) and is supported by the Excel dataset (D11). Some key findings from the report are:inclusion of leaves in biomass should be avoided. An exclusion might be conifer tops where the levels of most elements were sufficiently low to not exceed quality thresholds;harvesting time had a marked effect;while there were species differences between SRC willow varieties, no variety combined the best ranking in all parameters across all sites;there were major changesto Miscanthus quality during storage (decreasing fuel quality);for growers of Miscanthus, poplar SRF and spruce SRF, the key influences on many properties, i.e. season and storage, can be manipulated;SRC willow growers have a reasonable degree of control over some of the important feedstock characteristics by their choice of variety;for poplar SRF and spruce SRF, many properties can be adjusted by choice of plant part to market, and harvest timefeedstock properties were relatively insensitive to the way spruce SRF as grown.

The primary objective of this 2015/16/17 Project was to provide an understanding of UK produced biomass properties, how these vary and what causes this variability. This slideset was the first of seven deliverables to be produced under the first phase (2015/16) of this Project and the first of two under Milestone 1.The report provides the following: a schedule of work detailing the list of feedstocks to be sampled; the type, number and source of samples to be collected; a plan for gathering the samples? provenance data; a planned schedule of laboratory preparation and testing to be carried out; a clear plan for delivering the ETI project objectives. rationale for choices made list of laboratory tests to be performed list of provenance data collected sample site locations

We present a detailed report of a measurement of the neutron $\beta$-asymmetry parameter $A_0$, the parity-violating angular correlation between the neutron spin and the decay electron momentum, performed with polarized ultracold neutrons (UCN). UCN were extracted from a pulsed spallation solid deuterium source and polarized via transport through a 7-T magnetic field. The polarized UCN were then transported through an adiabatic-fast-passage spin-flipper field region, prior to storage in a cylindrical decay volume situated within a 1-T $2 \times 2\pi$ solenoidal spectrometer. The asymmetry was extracted from measurements of the decay electrons in multiwire proportional chamber and plastic scintillator detector packages located on both ends of the spectrometer. From an analysis of data acquired during runs in 2008 and 2009, we report $A_0 = -0.11966 \pm 0.00089_{-0.00140} ^{+0.00123}$, from which we extract a value for the ratio of the weak axial-vector and vector coupling constants of the nucleon, $\lambda = g_A/g_V = -1.27590 \pm 0.00239_{-0.00377}^{+0.00331}$. Complete details of the analysis are presented., Comment: 54 pages, 41 figures, submitted to Phys. Rev. C

An experiment has been performed to search for the muon- and electron-number non-conserving decay mu+ to e+_gamma. The upper limit for the branching ratio to be GAMMA(mu+ to e+_gamma)/GAMMA(mu+ to e+_nu_nubar) < 1.2e-11 with 90% confidence., 4 pages, 3 figures, submitted to Phys. Rev. Lett