Deducing spectroscopic factors from wave-function asymptotics

In a coupled-channel model, we explore the effects of coupling between configurations on the radial behavior of the wave function and, in particular, on the spectroscopic factor (SF) and the asymptotic normalization coefficient (ANC). We evaluate the extraction of a SF from the ratio of the ANC of the coupled-channel model to that of a single-particle approximation of the wave function. We perform this study within a core + n collective model, which includes two states of the core that connect by a rotational coupling. To get additional insights, we also use a simplified model that takes a delta function for the coupling potential. Calculations are performed for 11Be. Fair agreement is obtained between the SF inferred from the single-particle approximation and the one obtained within the coupled-channel models. Significant discrepancies are observed only for large coupling strength and/or large admixture, that is, a small SF. This suggests that reliable SFs can be deduced from the wave-function asymptotics when the structure is dominated by one configuration, that is, for a large SF.Comment: Title correcte

One-neutron halo structure by the ratio method

We present a new observable to study halo nuclei. This new observable is a particular ratio of angular distributions for elastic breakup and scattering. For one-neutron halo nuclei, it is shown to be independent of the reaction mechanism and to provide significant information about the structure of the projectile, including binding energy, partial-wave configuration, and radial wave function of the halo. This observable offers new capabilities for the study of nuclear structure far from stability.Comment: 9 pages, 4 figure

Time-dependent analysis of the nuclear and Coulomb dissociation of 11Be

The breakup of 11Be on carbon and lead targets around 70 MeV/nucleon is investigated within a semiclassical framework. The role of the 5/2+ resonance is analyzed in both cases. It induces a narrow peak in the nuclear-induced breakup cross section, while its effect on Coulomb breakup is small. The nuclear interactions between the projectile and the target is responsible for the transition toward this resonant state. The influence of the parametrization of the 10Be-n potential that simulates 11Be is also addressed. The breakup calculation is found to be dependent on the potential choice. This leads us to question the reliability of this technique to extract spectroscopic factors.Comment: 9 pages, 6 figures, to be published in the Proceedings of the Second Argonne/MSU/JINA/INT RIA Workshop on Reaction Mechanisms for rare Isotope Beams (2005

Comparing non-perturbative models of the breakup of neutron-halo nuclei

Breakup reactions of loosely-bound nuclei are often used to extract structure and/or astrophysical information. Here we compare three non-perturbative reaction theories often used when analyzing breakup experiments, namely the continuum discretized coupled channel model, the time-dependent approach relying on a semiclassical approximation, and the dynamical eikonal approximation. Our test case consists of the breakup of 15C on Pb at 68 MeV/nucleon and 20 MeV/nucleon.Comment: 8 pages, 6 figures, accepted for publication in Phys. Rev.

Exchange of information about physical education to support the transition of pupils from primary and secondary school

The purpose of this study was to identify how information about physical education is exchanged between secondary schools and their respective feeder primary schools, what information is exchanged and how this information is used. A secondary purpose was to look at whether there is any relationship between schools engaging in liaison activities and exchanging information about physical education, and between exchanging information and the number of associated secondary schools to which pupils are sent or feeder primary schools from which pupils are received. Questionnaires were sent to 177 secondary and 538 feeder primary schools. Responses from 80 secondary schools and 299 primary schools showed that the highest percentage of teachers exchanged information through written documentation, followed by discussion at cross phase liaison meetings. The type of information exchanged by the highest percentage of teachers was identified as generic information about key stage 2 and 3 of the National Curriculum for Physical Education (NCPE) areas of activity and schemes of work, rather than information about the specific physical education content covered or information about individual pupils, such as levels of attainment or ability. Further, results suggest that information may be used for pastoral purposes and that only a small percentage of teachers used the information exchanged to plan for continuity and progression in the physical education curriculum. There was a significant positive relationship between engagement in liaison activities and information received about the physical education curriculum followed by pupils, but a significant negative relationship for primary teachers between the number of different secondary schools to which pupils' progress and knowledge about the key stage 3 schemes of work that Year 6 pupils will follow in their associated secondary schools. These results are discussed in relation to continuity and progression in physical education in the transfer of pupils from primary to secondary schools

A study of current practice in liaison between primary and secondary schools in physical education

The purpose of this study was to investigate current practice in liaison between primary and secondary schools to promote continuity and progression in physical education during the transfer of pupils from Key Stage 2 to Key Stage 3 and to identify constraints to engaging in liaison activities. A questionnaire was completed by the head of the physical education department in secondary schools in five local education authorities in England that received pupils from primary schools in year 7 (n = 80) and by the physical education coordinator of the primary feeder schools of those secondary schools that responded to the questionnaire (n = 299). Results showed that 32 (43.8%) secondary teachers and 157 (53.4%) primary teachers identified that they had established contacts with their primary feeder schools or associated secondary schools respectively; and 49 (64.5%) secondary teachers but 114 (39.6%) primary teachers identified that currently they were engaged in liaison activities. There was a discrepancy between the percentages of teachers who indicated they had contacts with their primary feeder schools or associated secondary schools respectively, and who indicated they were engaged in liaison activities with them. These results suggested that contacts with and/or engagement in liaison activities between primary and secondary schools were not consistent across schools. A range of constraints for developing effective contacts/liaison activities were identified, with time being identified as the major constraint by both primary and secondary teachers. A range of suggestions for overcoming the constraints were also identified. These results are discussed in relation to findings from studies looking at liaison in other subjects and also in relation to the implications for schools

The transfer of pupils from primary to secondary school: A case study of a foundation subject - physical education

A series of transitions, from class to class, year to year and school to school, are integral to the education system in England. The transfer of pupils from primary to secondary education is an important stage of transition. Models for managing this transfer highlight different aspects of the experience, including social/pastoral integration and curriculum continuity and progression of individual pupils. The purpose of this study was to investigate the transfer of pupils from primary to secondary school in relation to physical education. Semi-structured interviews were conducted with 14 secondary school physical education heads of department. Results showed that although all of the heads of department reported the transfer of pupils from primary to secondary school to be very important in relation to physical education, this was not translated into practice. There was limited involvement in activities supporting the transfer from primary to secondary school, and what involvement there was placed greater emphasis on activities to support social/pastoral integration than to support continuity and progression of individual pupils during transfer. Some possible reasons for these results are considered, along with some suggestions for further research

An examination of knowledge prioritisation in secondary physical education teacher education courses

A number of terms have been used to describe knowledge needed for teaching, one of which is subject knowledge. How knowledge for teaching is conceptualised in teacher education prioritises some knowledge bases over other knowledge bases. Further, knowledge prioritised by student teachers is influenced by socialisation prior to and during an initial teacher education course and priorities for student teachers as they develop as teachers. Previous research in physical education teacher education points to the pre-eminence of content knowledge above other knowledge bases. The purpose of this study was to look at what knowledge is prioritised by student teachers, school-based mentors and university tutors working on three secondary physical education initial teacher education courses in England. Results showed that content knowledge was seen as having greater importance for student teachers and mentors, but university tutors generally conceptualised subject knowledge more broadly, suggesting that it should be seen as covering a number of knowledge bases needed for teaching. These results are discussed in relation to socialisation processes in education and phases of development. Although there is a clear physical education focus to this work, it is possible that student teachers learning to teach other subjects may also focus excessively on subject content knowledge above other knowledge bases

Asymptotic normalization of mirror states and the effect of couplings

Assuming that the ratio between asymptotic normalization coefficients of mirror states is model independent, charge symmetry can be used to indirectly extract astrophysically relevant proton capture reactions on proton-rich nuclei based on information on stable isotopes. The assumption has been tested for light nuclei within the microscopic cluster model. In this work we explore the Hamiltonian independence of the ratio between asymptotic normalization coefficients of mirror states when deformation and core excitation is introduced in the system. For this purpose we consider a phenomenological rotor + N model where the valence nucleon is subject to a deformed mean field and the core is allowed to excite. We apply the model to 8Li/8B, 13C/13N, 17O/17F, 23Ne/23Al, and 27Mg/27P. Our results show that for most studied cases, the ratio between asymptotic normalization coefficients of mirror states is independent of the strength and multipolarity of the couplings induced. The exception is for cases in which there is an s-wave coupled to the ground state of the core, the proton system is loosely bound, and the states have large admixture with other configurations. We discuss the implications of our results for novae.Comment: 8 pages, 2 figures, submitted to PR