5,872 research outputs found
The Diverse Properties of GPS Sources
We discuss the morphology and kinematics of five gigahertz-peaked spectrum
(GPS) sources that have been observed with the VLBA. We find a wide range of
observed properties including core-jet structure, superluminal motion,
variability, extended structure, and polarization, all of which appear to
deviate from commonly-accepted GPS paradigms (e.g., O'Dea 1998). We suggest
that the observed low frequency cutoff in GPS sources may be primarily due to
free-free absorption rather than synchrotron self-absorption.Comment: Proceedings of the 6th European VLBI Network Symposium, Ros E.,
Porcas R.W., Lobanov, A.P., & Zensus, J.A. (eds), MPIfR, Bonn, Germany. (4
pages, 5 figures, needs evn2002.cls style file
Delocalized Entanglement of Atoms in optical Lattices
We show how to detect and quantify entanglement of atoms in optical lattices
in terms of correlations functions of the momentum distribution. These
distributions can be measured directly in the experiments. We introduce two
kinds of entanglement measures related to the position and the spin of the
atoms
The QCD equation of state at finite T/\mu on the lattice
We present N_t=4 lattice results for the equation of state of 2+1 flavour
staggered, dynamical QCD at finite temperature and chemical potential. We use
the overlap improving multi-parameter reweighting technique to extend the
equation of state for non-vanishing chemical potentials. The results are
obtained along the line of constant physics. Our physical parameters extend in
temperature and baryon chemical potential upto \approx 500-600 MeV.Comment: 13 pages 9 figures, talk given at Finite Density QCD at Nara, Nara,
Japan, 10-12 July 200
Lattice QCD at non-vanishing density: phase diagram, equation of state
We propose a method to study lattice QCD at non-vanishing temperature (T) and
chemical potential (\mu). We use n_f=2+1 dynamical staggered quarks with
semi-realistic masses on L_t=4 lattices. The critical endpoint (E) of QCD on
the Re(\mu)-T plane is located. We calculate the pressure (p), the energy
density (\epsilon) and the baryon density (n_B) of QCD at non-vanishing T and
\mu.Comment: Contributed to Workshop on Strong and Electroweak Matter (SEWM 2002),
Heidelberg, Germany, 2-5 Oct 200
VLBI imaging of extremely high redshift quasars at 5 GHz
We present very long baseline interferometry (VLBI) images of ten very high
redshift (z>3) quasars at 5 GHz. The sources 0004+139, 0830+101, 0906+041,
0938+119 and 1500+045 were observed in September 1992 using a global VLBI
array, while 0046+063, 0243+181, 1338+381, 1428+423 and 1557+032 were observed
in October 1996 with the European VLBI Network and Hartebeesthoek, South
Africa. Most of the sources are resolved and show asymmetric structure. The
sample includes 1428+423, the most distant radio loud quasar known to date
(z=4.72). It is barely resolved with an angular resolution of about 2.0*1.4
mas.Comment: Astronomy and Astrophysics, in press, Latex2e, 10 pages, 3 figures
(and lots of sub-figures
Influences on students’ attainment and progress in Key Stage 3: academic outcomes in English, Maths and Science in Year 9
The Effective Pre-school, Primary and Secondary Education Project (EPPSE) has investigated the academic and social-behavioural development of approximately 3,000 children from the age of 3+ years since 1997. This Research Brief focuses on the relationships between a range of individual student, family, home, pre-, primary and secondary school characteristics and students\u27 academic attainment in English, maths and science in Year 9 at secondary school (age 14). It compares the latest findings with those found for students\u27 attainment at younger ages. It also highlights the influences of secondary school on students\u27 attainment in the core curriculum areas and studies their academic progress across Key Stage 3 between the ages of 11 and 14
Effective pre-school, primary and secondary education project (EPPSE 3-14): students’ reports of their experiences of school in Year 9
The Effective Pre-school, Primary and Secondary Education Project (EPPSE) has inves tigated the academic and social
behavioural (+ in the later stages the affective)
development of approximately 3,000 children from the age of 3+ years since 1997. This report presents the results of analyses related to student’s experiences in Year 9 (age 14), with the purpose of creating measures of both school and classroom life as experienced by students. These measures have been used in the analysis of academic and social-behavioural outcomes as well as dispositions to investigate whether a student’s reported experience of school can significantly predict outcomes in other areas. The findings highlight the importance of the ‘student voice’ and provide an insight into the experiences of teenagers in the first decade of the 21st Century
Effective Pre-school, Primary and Secondary Education 3-14 Project (EPPSE 3-14): influences on students’ dispositions in Key Stage 3: exploring enjoyment of school, popularity, anxiety, citizenship values and academic self-concept in Year 9
The Effective Pre-school, Primary and Secondary Education Project (EPPSE) has investigated the academic and social-behavioural development of approximately 3,000 children from the age of 3+ years since 1997. This Report and Research Brief reports on students’ dispositions when they were age 14 (Year 9) in six main areas: ‘enjoyment of school’, ‘academic self concept’ (English and maths), ‘popularity’, ‘citizenship values’ and ‘anxiety’. It examines how these dispositions have changed during Key Stage 3 (KS3) and the relationships between dispositions and a range of individual student, family, home, pre-, primary and secondary school measures. It shows how school experiences help to shape dispositions, and also explores the relationships between dispositions to school and students’ academic and social-behavioural outcomes. The findings highlight the importance of the ‘student voice’ and provides an insight into the experiences of teenagers in the first decade of the 21st Century
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