400 research outputs found
Search for d^* Dibaryon by Double-radiative Capture on Pionic Deuterium
We report a search for d^* dibaryon production by double-radiative capture on
pionic deuterium. The experiment was conducted at the TRIUMF cyclotron using
the RMC cylindrical pair spectrometer, and detected gamma-ray coincidences
following pion stops in liquid deuterium. We found no evidence for narrow
dibaryons, and obtained a branching ratio upper limit, BR < 6.7 times 10^{-6}
(90% C.L.), for narrow d^* production in the mass range from 1920 to 1980 MeV.
Replaced with Physics Letter B accepted version and corrected normalization.Comment: 9 pages, 4 figure
Data acquisition system for the MuLan muon lifetime experiment
We describe the data acquisition system for the MuLan muon lifetime
experiment at Paul Scherrer Institute. The system was designed to record muon
decays at rates up to 1 MHz and acquire data at rates up to 60 MB/sec. The
system employed a parallel network of dual-processor machines and repeating
acquisition cycles of deadtime-free time segments in order to reach the design
goals. The system incorporated a versatile scheme for control and diagnostics
and a custom web interface for monitoring experimental conditions.Comment: 19 pages, 8 figures, submitted to Nuclear Instruments and Methods
Test of isospin symmetry via low energy H(,) charge exchange
We report measurements of the differential cross
sections at six momenta (104-143 MeV/c) and four angles (0-40 deg) by detection
of -ray pairs from decays using the TRIUMF
RMC spectrometer. This region exhibits a vanishing zero-degree cross section
from destructive interference between s-- and p--waves, thus yielding special
sensitivity to pion-nucleon dynamics and isospin symmetry breaking. Our data
and previous data do not agree, with important implications for earlier claims
of large isospin violating effects in low energy pion-nucleon interactions.Comment: 5 pages, 3 figures, submitted to Physical Review Letter
Ortho-para transition rate in -molecular hydrogen and the proton's induced pseudoscalar coupling
We report a measurement of the ortho-para transition rate in the pp
molecule. The experiment was conducted at TRIUMF via the measurement of the
time dependence of the 5.2 MeV neutrons from muon capture in liquid hydrogen.
The measurement yielded an ortho-para rate s that is substantially larger than the
earlier result of Bardin {\it et al.} We discuss the striking implications for
the proton's induced pseudoscalar coupling .Comment: 4 pages, 3 figures, submitted to Phys. Rev. Let
Muon Capture on the Proton and Deuteron
By measuring the lifetime of the negative muon in pure protium (hydrogen-1),
the MuCap experiment determines the rate of muon capture on the proton, from
which the proton's pseudoscalar coupling g_p may be inferred. A precision of
15% for g_p has been published; this is a step along the way to a goal of 7%.
This coupling can be calculated precisely from heavy baryon chiral perturbation
theory and therefore permits a test of QCD's chiral symmetry. Meanwhile, the
MuSun experiment is in its final design stage; it will measure the rate of muon
capture on the deuteron using a similar technique. This process can be related
through pionless effective field theory and chiral perturbation theory to other
two-nucleon reactions of astrophysical interest, including proton-proton fusion
and deuteron breakup.Comment: Submitted to the proceedings of the 2007 Advanced Studies Institute
on Symmetries and Spin (SPIN-Praha-2007
Recent developments in effective field theory
We will give a short introduction to the one-nucleon sector of chiral
perturbation theory and will address the issue of a consistent power counting
and renormalization. We will discuss the infrared regularization and the
extended on-mass-shell scheme. Both allow for the inclusion of further degrees
of freedom beyond pions and nucleons and the application to higher-loop
calculations. As applications we consider the chiral expansion of the nucleon
mass to order O(q^6) and the inclusion of vector and axial-vector mesons in the
calculation of nucleon form factors.Comment: 8 pages, 6 figures, invited talk given at International School of
Nuclear Physics, 29th Course "Quarks in Hadrons and Nuclei", Erice, Sicily,
16 - 24 September 200
Caste: experiences in South Asia and beyond
This is an accepted manuscript of an article published by Taylor and Francis in Contemporary South Asia on 03/07/2017, available online: https://doi.org/10.1080/09584935.2017.1360246
The accepted version of the publication may differ from the final published version.This special issue of Contemporary South Asia seeks to capture the diversity and situatedness of the caste experience and deepen our understanding of caste dynamics and lives in the twenty-first century. In this Introduction, we highlight the continuing salience of caste, offer an overview of theoretical understandings of caste and foreground the importance of analysing caste in the present as a dynamic form of human relations, rather than a remnant of tradition. Following on from this, we highlight the increasingly global spread of caste and reflect on what happens to caste-based social relations when they traverse continents. In conclusion, we introduce the papers that make up this special issue. Taken together, they speak to changes in attitudes towards caste, but also the persistence of caste-based identities and dynamics in India and Britain. Even though the papers presented in this special issue work with the assumption of caste being a reality in and among the Indians, caste-like status hierarchies have existed in most, if not all, societies, and they continue to persist and intersect with other forms of differences/inequalities.Published versio
Care homes education: what can we learn?
Medical care received by care home residents can be variable. Initiatives, such as matron-led community teams, ensure a timely response to alerts about unwell residents. But early recognition of deterioration is vital in accessing this help. The aim of this project was to design and deliver an education programme for carers. It was hypothesised that the implementation of a teaching programme may result in improved medical care for residents. By understanding the enablers and barriers to implementing teaching, we hoped to identify the components of a successful teaching programme. Four care homes in Enfield received training on topics such as deterioration recognition over a 1-year period. The project was evaluated at 3, 6 and 9âmonths. Each evaluation comprised: pre-and-post-teaching questionnaires, focus groups, analysis of percentages of staff trained, review of overall and potentially avoidable, hospital admission rates. A Plan-Do-Study-Act cycle structure was used. The programme was well-received by carers, who gave examples of application of learning. Modules about conditions frequently resulting in hospital admission, or concerning real cases, demonstrated the best pre-and-post lesson change scores. However, the reach of the programme was low, with attendance rates between 5% and 28%. Overall, the percentage of staff trained in deterioration recognition ranged from 35% (care home one) to 12% (care home three). Hospital admissions reduced from 37 hospital admissions to 20 over the duration of the project. Potentially avoidable admissions reduced from 16 to 5. Proving causality to the intervention was difficult. Factors facilitating delivery of training included a flexible approach, an activity-based curriculum, alignment of topics with real cases and embedding key messages in every tutorial. Barriers included: time pressures, shift work, low attendance rates, inequitable perception of the value of teaching and IT issues. Care home factors impacting on delivery included: stability of management and internal communication systems.please ensure space here
- âŠ