Fri·Jul 10, 2009Friday·July 10, 2009

1. 01*

   Spin Sum Rules at Low $Q^2$

   Jian-ping Chen🇺🇸

   Recent precision spin-structure data from Jefferson Lab have significantly advanced our knowledge of nucleon structure at low $Q^2$. Results on the neutron spin sum rules and polarizabilities in the low to intermediate $Q^2$ region are presented. The Burkhardt-Cuttingham Sum Rule was verified within experimental uncertainties. When comparing with theoretical calculations, results on spin polarizability show surprising disagreements with Chiral Perturbation Theory predictions. Preliminary results on first moments at very low $Q^2$ are also presented.

   nucl-exhep-exhep-phnucl-thAIP Conf.Proc.(2009)·0 citations
2. 02*

   Comparative studies of the interaction in the low energy ppeta and ppeta' systems

   Pawel Klaja🇵🇱

   The COSY-11 collaboration measured the pp -> ppeta and pp -> ppeta' reactions in order to perform comparative studies of the interactions within the proton-proton-meson system. This thesis presents in detail the analysis of the pp -> ppeta' reaction which was measured at the proton beam momentum of 3.260 GeV/c. The elaboration results in differential distributions of squared invariant proton-proton (s_pp) and proton-eta' (s_peta') masses, as well as in angular distributions and the total cross section at an excess energy of 16.4 MeV. The differential distributions s_pp and s_peta' are compared to theoretical predictions and to the analogous spectra determined for the pp -> ppeta reaction. The comparison of the results for the eta and eta' meson production rather excludes the hypothesis that the enhancement observed in the invariant mass distributions is due to the meson-proton interaction. Further, the shapes of the distributions do not favour any of the postulated theoretical models.

   nucl-ex5 citations
3. 03*

   ALICE pp physics programme

   Ingrid Kraus (for the ALICE Collaboration)🇩🇪

   The physics programme of the ALICE experiment at CERN-LHC comprises besides studies of high-energy heavy-ion collisions measurements of proton-proton interactions at unprecedented energies, too. This paper focuses on the global event characterisation in terms of the multiplicity distribution of charged hadrons and mean transverse momentum. These bulk observables become accessible because the detector features excellent track reconstruction, especially at low transverse momenta. The measurement of strange hadrons is of particular interest since the strange-particle phase-space was found to be suppressed beyond canonical reduction at lower center-of-mass energies and the production mechanism of soft particles is not yet fully understood. Here we benefit in particular from particle identification down to very low transverse momentum, i.e. 100 - 300 MeV/c, giving access to spectra and integrated yields of identified hadrons. Equipped with these features, ALICE will play a complementary role w.r.t. other LHC experiments. New interest in the soft part of pp collisions arose recently and new insights in the physics of the underlying event are expected from both, theory and experiment.

   nucl-ex0 citations
4. 04*

   The MAJORANA DEMONSTRATOR: An R&D project towards a tonne-scale germanium neutrinoless double-beta decay search

   Reyco Henning (for the MAJORANA Collaboration)

   The MAJORANA collaboration is pursuing the development of the so-called MAJORANA DEMONSTRATOR. The DEMONSTRATOR is intended to perform research and development towards a tonne-scale germanium-based experiment to search for the neutrinoless double-beta decay of Ge-76. The DEMONSTRATOR can also perform a competitive direct dark matter search for light WIMPs in the 1-10 GeV/c^2 mass range. It will consist of approximately 60-kg of germanium detectors in an ultra-low background shield located deep underground at the Sanford Underground Laboratory in Lead, SD. The DEMONSTRATOR will also perform background and technology studies, and half of the detector mass will be enriched germanium. This talk will review the motivation, design, technology and status of the DEMONSTRATOR.

   nucl-exAIP Conf.Proc.(2009)·19 citations
5. 05*

   Discovery of the Silver Isotopes

   A. Schuh🇺🇸 · A. Fritsch🇺🇸 · J.Q. Ginepro🇺🇸 · M. Heim🇺🇸 · A. Shore🇺🇸 · M. Thoennessen🇺🇸

   Thirty-eight silver isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

   nucl-exAtom.Data Nucl.Data Tabl.(2010)·5 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.