Dynamic polarization potential due to ⁶Li breakup on ¹²C

For 6Li scattering from 12C at five laboratory energies from 90 to 318 MeV, we study the dynamic polarization potential, DPP, due to the breakup of the projectile. The breakup is evaluated using standard continuum discretized coupled-channels formalism applied to a two-body cluster model of the projectile. The DPP is evaluated over a wide radial range using both direct S-matrix-to-potential inversion and trivially equivalent local potential methods which yield substantially and systematically different results. The radius at which the real DPP changes from external repulsion to interior attraction varies systematically with energy. This should be experimentally testable because, according to notch tests, this crossover radius is within a radial range to which elastic scattering should be sensitive. The imaginary DPP has an emissive (generative) region at the lower energies; this may be associated with counterintuitive properties of |SL|

Significant features of ⁸B scattering from ²⁰⁸Pb at 170.3 MeV

The scattering of proton-halo nucleus 8B from 208Pb at 170.3 MeV is shown to reveal a distinctive pattern in the change in |SL| that is induced by coupling to breakup channels. The same pattern had been found for 8B scattering from 58Ni at 30 MeV, an energy near the Coulomb barrier, and has been linked to various other respects in which scattering for this proton-halo nucleus differs from that of other light, weakly bound nuclei. The increase in |SL | forL < 80, induced by breakup coupling, is associated with a substantial repulsive region in the dynamic polarization potential as determined by exact inversion. This repulsion appears to reduce the penetration of the projectile into the absorptive region of the interaction. This accounts for the fact that the increase in the total reaction cross section, due to breakup, is much less than the breakup cross section, and is consistent with the relatively small effect of breakup on the elastic scattering angular distribution compared with the large breakup cross section

The NN phase shifts in the extended quark-delocalization, color-screening model

An alternative method is applied to the study of nucleon-nucleon(NN) scattering phase shifts in the framework of extended quark delocalization, color-screening model(QDCSM), where the one-pion-exchange(OPE) with short-range cutoff is included.Comment: 5 pages, 3 figures, two-colum

Geology orbiter comparison study

Instrument requirements of planetary geology orbiters were examined with the objective of determining the feasibility of applying standard instrument designs to a host of terrestrial targets. Within the basic discipline area of geochemistry, gamma-ray, X-ray fluorescence, and atomic spectroscopy remote sensing techniques were considered. Within the discipline area of geophysics, the complementary techniques of gravimetry and radar were studied. Experiments using these techniques were analyzed for comparison at the Moon, Mercury, Mars and the Galilean satellites. On the basis of these comparative assessments, the adaptability of each sensing technique was judged as a basic technique for many targets, as a single instrument applied to many targets, as a single instrument used in different mission modes, and as an instrument capability for nongeoscience objectives

Opinion Mining on Non-English Short Text

As the type and the number of such venues increase, automated analysis of sentiment on textual resources has become an essential data mining task. In this paper, we investigate the problem of mining opinions on the collection of informal short texts. Both positive and negative sentiment strength of texts are detected. We focus on a non-English language that has few resources for text mining. This approach would help enhance the sentiment analysis in languages where a list of opinionated words does not exist. We propose a new method projects the text into dense and low dimensional feature vectors according to the sentiment strength of the words. We detect the mixture of positive and negative sentiments on a multi-variant scale. Empirical evaluation of the proposed framework on Turkish tweets shows that our approach gets good results for opinion mining

Market reaction to seasoned offerings in China

This study examines stock market reaction to the announcement of various forms of seasoned issues in China. Our empirical evidence demonstrates that market reactions differ in ways that suggest a difference between management’s internal assessment and the market’s assessment of the stock price. The market responds unfavourably to the announcement, notably in the case of rights issues and also with regard to open offers. Private placements experience an unfavourable pre-announcement reaction, which contrasts with the favourable reaction after the event. Convertible bond issues generate positive excess returns consistent with the market’s confidence that they can help to align management and shareholders’ interests. Further investigation shows that market reaction is related to factors specific to the issuer and issue by reference to the period immediately surrounding the issue. Specifically, ownership concentration, agency matters connected with equity offerings, investor protection connected with fund allocation and security pricing, and the influence of powerful moneyed interests together provide an instructive insight into market reaction. Institutional inefficiency pertaining to underwriting, auditing, analysts’ forecasts and credit ratings are found to have a weak association with market price, consistent with due public scepticism concerning management and their gatekeepers