The direct 3α decay branch from the 02+ state at Ex=7.65 MeV in 12C, which is known as the Hoyle state, is considered to affect the triple-α reaction rate strongly and to give crucial information on its structure. We have performed a high-precision measurement of the 3α decay from this state using the 12C(12C,3α)12C reaction at E12C=110 MeV. The branching ratio of the direct 3α decay was under the detection limit in the present experiment. By comparing with Monte Carlo simulations for three decay mechanisms as the sequential decay through the ground state of ^{8}Be, the direct decay with equal energies of three α particles, and the direct decay to the phase space uniformly, we have obtained the upper limit of 0.2% on the direct 3α decay.
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http://dx.doi.org/10.1103/PhysRevLett.113.102501 | DOI Listing |
Phys Rev E
November 2022
Cardiff School of Engineering, Cardiff University Queens Buildings, The Parade, Cardiff CF24 3AA, United Kingdom.
We apply the functional renormalization group (fRG) to study relaxation in a stochastic process governed by an overdamped Langevin equation with one degree of freedom, exploiting the connection with supersymmetric quantum mechanics in imaginary time. After reviewing the functional integral formulation of the system and its underlying symmetries, including the resulting Ward-Takahashi identities for arbitrary initial conditions, we compute the effective action Γ from the fRG, approximated in terms of the leading and subleading terms in the gradient expansion: the local potential approximation and wave-function renormalization, respectively. This is achieved by coarse graining the thermal fluctuations in time resulting in, e.
View Article and Find Full Text PDFEur J Pediatr
December 2022
Faculty of Health and Social Sciences, Bournemouth University, Bournemouth Gateway Building, St. Paul's Lane, Bournemouth, BH8 8GP, England.
Infant cardiopulmonary resuscitation (iCPR) is often poorly performed, predominantly because of ineffective learning, poor retention and decay of skills over time. The aim of this study was to investigate whether an individualized, competence-based approach to simulated iCPR retraining could result in high skill retention of infant chest compressions (iCC) at follow-up. An observational study with 118 healthcare students was conducted over 12 months from November 2019.
View Article and Find Full Text PDFMed Image Anal
November 2022
School of Physics and Astronomy, Cardiff University, The Parade, Cardiff CF24 3AA, UK. Electronic address:
Despite their widespread use in cell biology, fluorescence lifetime imaging microscopy (FLIM) data-sets are challenging to analyse, because each spatial position can contain a superposition of multiple fluorescent components. Here, we present a data analysis method employing all information in the available photon budget, as well as being fast. The method, called uFLIM, determines spatial distributions and temporal dynamics of multiple fluorescent components with no prior knowledge.
View Article and Find Full Text PDFWater Res
May 2021
Hydro-environmental Research Centre (HRC), School of Engineering, Cardiff University, Cardiff CF24 3AA, UK.
In recent years, society has become more aware and concerned with the environmental and human health impacts of population growth and urbanisation. In response, a number of legislative measures have been introduced within Europe (and globally), which have sparked much cross-disciplinary research aimed at predicting and quantifying these impacts, and suggesting mitigation measures. In response to such measures this paper is focused on improving current understanding of, and simulating water quality, in the form of bacterial transport and decay, in the aquatic environment and particularly in macro-tidal environments.
View Article and Find Full Text PDFNano Lett
October 2020
London Centre for Nanotechnology, University College London, London WC1H 0AH, United Kingdom.
We investigate gate-induced quantum dots in silicon nanowire field-effect transistors fabricated using a foundry-compatible fully depleted silicon-on-insulator (FD-SOI) process. A series of split gates wrapped over the silicon nanowire naturally produces a 2 × bilinear array of quantum dots along a single nanowire. We begin by studying the capacitive coupling of quantum dots within such a 2 × 2 array and then show how such couplings can be extended across two parallel silicon nanowires coupled together by shared, electrically isolated, "floating" electrodes.
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