1,097,754 research outputs found
Primordial Nucleosynthesis: from precision cosmology to fundamental physics
We present an up-to-date review of Big Bang Nucleosynthesis (BBN). We discuss
the main improvements which have been achieved in the past two decades on the
overall theoretical framework, summarize the impact of new experimental results
on nuclear reaction rates, and critically re-examine the astrophysical
determinations of light nuclei abundances. We report then on how BBN can be
used as a powerful test of new physics, constraining a wide range of ideas and
theoretical models of fundamental interactions beyond the standard model of
strong and electroweak forces and Einstein's general relativity.Comment: 148 pages, 66 figures, revised version accepted by Physics Report
Tulczyjew triples and higher Poisson/Schouten structures on Lie algebroids
We show how to extend the construction of Tulczyjew triples to Lie algebroids
via graded manifolds. We also provide a generalisation of triangular Lie
bialgebroids as higher Poisson and Schouten structures on Lie algebroids.Comment: 28 pages. Completely rewritten and improved. Typos corrected. A
version is to appear in Reports on Mathematical Physics, Vol.66, No. 2, 2010.
Further minor typos correcte
Gamma ray production cross sections in proton induced reactions on natural Mg, Si and Fe targets over the proton energy range 30 up to 66 MeV
Gamma-ray excitation functions have been measured for 30, 42, 54 and 66 MeV
proton beams accelerated onto C + O (Mylar), Mg, Si, and Fe targets of
astrophysical interest at the separate-sector cyclotron of iThemba LABS in
Somerset West (Cape Town, South Africa). A large solid angle, high energy
resolution detection system of the Eurogam type was used to record Gamma-ray
energy spectra. Derived preliminary results of Gamma-ray line production cross
sections for the Mg, Si and Fe target nuclei are reported and discussed. The
current cross section data for known, intense Gamma-ray lines from these nuclei
consistently extend to higher proton energies previous experimental data
measured up to Ep ~ 25 MeV at the Orsay and Washington tandem accelerators.
Data for new Gamma-ray lines observed for the first time in this work are also
reported.Comment: 11 pages, 6 figures. IOP Institute of Physics Conference Nuclear
Physics in Astrophysics VII, 28th EPF Nuclear Physics Divisional Conference,
May 18-22 2015, York, U
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