On the nucleon-nucleon interaction leading to a standing wave instability in symmetric nuclear matter

We examine a recently proposed nucleon-nucleon interaction, claimed by its authors both realistic and leading to a standing wave instability in symmetric nuclear matter. Contrary to these claims, we find that this interaction leads to a serious overbinding of 4He, 16O and 40Ca nuclei when the Hartree-Fock method is properly applied. The resulting nuclear densities contradict the experimental data and all realistic Hartree-Fock results.Comment: 4 pages, 1 figur

Mass spectrometry-directed synthesis of early–late sulfide-bridged heterobimetallic complexes from the metalloligand [Pt₂(PPh₃)₄(μ-S)₂] and oxo compounds of vanadium(V), molybdenum(VI) and uranium(VI)

The metalloligand [Pt₂(PPh₃)₄(μ-S)₂] has been found to react with the transition metal oxo compounds, ammonium metavanadate, sodium molybdate, and the actinide complex uranyl nitrate to give sulfide-bridged heterobimetallic complexes [Pt₂(PPh₃)₄(μ₃-S)₂VO(OMe)₂]⁺, [Pt₂(PPh₃)₄(μ₃-S)₂MoO₂(OMe)]⁺, and [Pt₂(PPh₃)₄(μ₃-S)₂UO₂( ₂-NO₃)₂], respectively. Electrospray mass spectrometry (ESMS) was used to probe the reactivity of [Pt₂(PPh₃)₄(μ-S)₂] and thus identify likely targets for isolation and characterization. ESMS has also been used to investigate fragmentation pathways of the new species. No bimetallic species were detected with hydrated La(NO₃)₃or Th(NO₃)₄, or with the lanthanide shift reagent Eu(fod)₃ (fod = 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionate). X-Ray crystal structure determinations have been carried out on [Pt₂(PPh₃)₄(μ₃-S)₂VO(OMe)₂]⁺, 2, (as its hexafluorophosphate salt) and [Pt₂(PPh₃)₄(μ₃-S)₂UO₂( ₂-NO₃)₂], 4. The vanadium atom of 2 has a distorted square pyramidal geometry, while the uranium in 4 has the expected linear dioxo coordination geometry, with two bidentate nitrates and a bidentate {Pt₂S₂} moiety

Deformation Projected RMF Calculation for Cr and Fe nuclei in Hybrid Derivative Coupling Model

The ground state properties of even mass Cr and Fe isotopes are studied using the generalized hybrid derivative coupling model. The energy surface of each isotope is plotted as a function of the mass quadrupole moment. The neutron numbers N=20 and N=40 are seen to remain magic numbers but N= 28 and 50 are predicted to be non-magic. The neutron number N=70 turns out to be a magic number according to the present calculation. In all the isotopes studied the calculated binding energy values are less than those obtained from experiment while the deformation is in better agreement.Comment: To appear in Int. Jour. Mod. Phys.

A rapid screening, “combinatorial-type” survey of the metalloligand chemistry of Pt₂(PPh₃)₄(μ-S)₂ using electrospray mass spectrometry

Electrospray mass spectrometry is a rapid and powerful technique for a combinatorial-like survey of the chemistry of the metalloligand Pt₂(PPh₃)₄(μ-S)₂, leading to the successful isolation and crystallographic characterisation of the novel protonated species Pt₂(PPh₃)₄(μ-S)(μ-SH) together with a range of metallated derivatives

Beta decay of 115-In to the first excited level of 115-Sn: Potential outcome for neutrino mass

Recent observation of beta decay of 115-In to the first excited level of 115-Sn with an extremely low Q_beta value (Q_beta ~ 1 keV) could be used to set a limit on neutrino mass. To give restriction potentially competitive with those extracted from experiments with 3-H (~2 eV) and 187-Re (~15 eV), atomic mass difference between 115-In and 115-Sn and energy of the first 115-Sn level should be remeasured with higher accuracy (possibly of the order of ~1 eV).Comment: 9 pages, 3 figures; talk at the NANP'05 Conferenc

The NUBASE evaluation of nuclear and decay properties

This paper presents the first version of the NUBASE evaluation of nuclear and decay properties of nuclides in their ground- and isomeric-states. All nuclides for which some experimental information is known are considered. NUBASE has basically been derived from the “Evaluated Nuclear Structure Data Files” and from the “Atomic Mass Evaluation” of 1995, but it also includes information from recent literature or literature missed in one of these two evaluations and is meant to cover all experimental data along with their references. In case no experimental data is available, whenever possible, trends in the systematics of neighboring nuclides have been used to derive estimated values (labeled in the database as non-experimental). Adopted procedures and policies are presented

The Nuclear Science References (NSR) Database and Web Retrieval System

The Nuclear Science References (NSR) database together with its associated Web interface, is the world's only comprehensive source of easily accessible low- and intermediate-energy nuclear physics bibliographic information for more than 200,000 articles since the beginning of nuclear science. The weekly-updated NSR database provides essential support for nuclear data evaluation, compilation and research activities. The principles of the database and Web application development and maintenance are described. Examples of nuclear structure, reaction and decay applications are specifically included. The complete NSR database is freely available at the websites of the National Nuclear Data Center http://www.nndc.bnl.gov/nsr and the International Atomic Energy Agency http://www-nds.iaea.org/nsr.Comment: 16 pages, 5 figure

Anomalous Behavior of 2+ Excitations around 132Sn

In certain neutron-rich Te isotopes, a decrease in the energy of the first excited 2+ state is accompanied by a decrease in the E2 strength to that state from the ground state, contradicting simple systematics and general intuition about quadrupole collectivity. We use a separable quadrupole-plus-pairing Hamiltonian and the quasiparticle random phase approximation to calculate energies, B(E2,0+ -> 2+) strengths, and g factors for the lowest 2+ states near 132Sn (Z >= 50). We trace the anomalous behavior in the Te isotopes to a reduced neutron pairing above the N = 82 magic gap.Comment: 1 figure added. to be published in Phys. Rev.

Are Neutron-Rich Elements Produced in the Collapse of Strange Dwarfs ?

The structure of strange dwarfs and that of hybrid stars with same baryonic number is compared. There is a critical mass (M~0.24M_sun) in the strange dwarf branch, below which configurations with the same baryonic number in the hybrid star branch are more stable. If a transition occurs between both branches, the collapse releases an energy of about of 3x10^{50} erg, mostly under the form of neutrinos resulting from the conversion of hadronic matter onto strange quark matter. Only a fraction (~4%) is required to expel the outer neutron-rich layers. These events may contribute significantly to the chemical yield of nuclides with A>80 in the Galaxy, if their frequency is of about one per 1500 years.Comment: Accepted for publication in IJMP

Practical reasoning in political discourse: The UK government's response to the economic crisis in the 2008 Pre-Budget Report

This article focuses on practical reasoning in political discourse and argues for a better integration of argumentation theory with critical discourse analysis (CDA). Political discourse and its specific genres (for example, deliberation) primarily involve forms of practical reasoning, typically oriented towards finding solutions to problems and deciding on future courses of action. Practical reasoning is a form of inference from cognitive and motivational premises: from what we believe (about the situation or about means—end relations) and what we want or desire (our goals and values), leading to a normative judgement (and often a decision) concerning action. We offer an analysis of the main argument in the UK government’s 2008 Pre-Budget Report (HM Treasury, 2008) and suggest how a critical evaluation of the argument from the perspective of a normative theory of argumentation (particularly the informal logic developed by Douglas Walton) can provide the basis for an evaluation in terms of characteristic CDA concerns. We are advancing this analysis as a contribution to CDA, aimed at increasing the rigour and systematicity of its analyses of political discourse, and as a contribution to the normative concerns of critical social science