Criminal neighbourhoods: does the density of prior offenders encourage others to commit crime?

Using crime data over a period of a decade for Glasgow, this paper explores whether the density of prior offenders in a neighbourhoods has an influence on the propensity of others to (re)commence offending. The study shows that the number of ‘newly active’ offenders in a neighbourhood in the current quarter is positively associated with the density of prior offenders for both violent and property crime from the previous two years. In the case of ‘newly active’ property offenders, the relationship with active prior offenders is only apparent when prior offender counts exceed the median. The paper postulates that intraneighbourhood social mechanisms may be at work to create these effects. The results suggest that policies which concentrate offenders in particular neighbourhoods may increase the number of ‘newly active’ offenders, and point to evidence of a threshold at which these effects take place

Inclusive Nucleon Emission Induced by Quasi--Elastic Neutrino--Nucleus Interactions

We study the quasi--elastic contribution to the inclusive $(\nu_l,\nu_l N)$, $(\nu_l,l^- N)$, $({\bar \nu}_l,{\bar \nu}_l N)$ and $({\bar \nu}_l,l^+ N)$ reactions in nuclei using a Monte Carlo simulation method to account for the rescattering of the outgoing nucleon. As input, we take the reaction probability from the microscopical many body framework developed in Phys. Rev. {\bf C70} (2004) 055503 for charged-current induced reactions, while for neutral currents we use results from a natural extension of the model described in that reference. The nucleon emission process studied here is a clear signal for neutral--current neutrino driven reactions, that can be used in the analysis of future neutrino experiments.Comment: 23 pages, 17 figures; Version 2: few typos correcte

The electric form factor of the neutron and its chiral content

Considering the nucleon as a system of confined valence quarks surrounded by pions we derive a Galster-like parameterization of the neutron electric form factor $G_E^n$. Furthermore, we show that the proposed parameterization can be linked to properties of the pion cloud. By this, the high quality data for the pion form factor can be used in predictions of $G_E^n$ in the low $Q^2$ region, where the direct double polarization measurements are not available.Comment: 11 pages, 3 figure

Income Diversity Within Neighborhoods and Very Low-Income Families

The past decades have witnessed increasing concern over the family ills engendered by neighborhoods inhabited overwhelmingly by families with limited resources. This study focuses on a different sort of residential context—neighborhoods with substantial income mixing—and the extent to which very low-income (VLI) families—those earning less than 50 percent of the area median income (AMI)—live in them. The study’s primary units of analysis are the 100 largest metropolitan areas in the United States, according to the 2000 Census, and the secondary units of analysis are census tracts. The study specifies six mutually exclusive income groups based on the ratios relative to AMI, as defined by the U.S. Department of Housing and Urban Development. It also specifies four groups of neighborhoods according to their diversity of the six income groups, as measured by an entropy index. The descriptive results show that in 2000 (1) most neighborhoods had high diversity, although a decline is apparent in the overall income diversity of neighborhoods and in the share comprising high-diversity neighborhoods; (2) no neighborhoods with median incomes of less than 50 percent of AMI had high diversity; (3) 19 percent of all high-diversity neighborhoods (on average) consist of VLI families and 65 percent of all VLI families live in high-diversity neighborhoods, although both percentages have declined since 1970; (4) 5 percent of VLI families live in neighborhoods with median incomes of less than 50 percent of AMI, twice the percentage of 1970 but lower than in 1990; and (5) exposure of VLI families to other VLI families and moderate-income groups has steadily fallen since 1970 and concomitantly increased for families that have very high incomes (VHIs); indeed, the exposure to VHI families is approximately the same as exposure to other VLI families. This article addresses the mixed implications of these trends for the potential socioeconomic mobility of VLI families. This research was presented at Wayne State University\u27s 2010 Sociology Student Research & Awards Day. Presentation slides are included as supplemental materials. This research was supported by a grant from the U.S. Department of Housing and Urban Development, Office of Policy Development and Research. The opinions expressed in this article are those of the authors and do not necessarily reflect those of the Department

The role of the pion cloud in electroproduction of the Δ\Delta(1232)

We calculate the ratios $E2/M1$ and $C2/M1$ of the multipole amplitudes for electroproduction of the $\Delta$(1232) in the range of photon virtuality $0<-K^2<1$~GeV$^2$ in a chiral chromodielectric model and a linear $\sigma$-model. We find that relatively large experimental values can be explained in terms of the pion contribution alone; the contribution arising from d-state quark admixture remains below 10\%. We describe the pion cloud as a coherent state and use spin and isospin projection to obtain the physical nucleon and the $\Delta$. The $A_{1/2}$ and $A_{3/2}$ amplitudes are reasonably well reproduced in the $\sigma$-model; in the chromodielectric model, however, they are a factor of two too small.Comment: 10 pages LaTeX2e, 3 LaTeX figures within the text; Requires elsart.cls (included in the self-unpacking uuencoded gzipped file). (Accepted for publication in Phys. Lett. B

Can neutron electromagnetic form factors be obtained by polarized inclusive electron scattering off polarized three-nucleon bound states?

The investigation of the electromagnetic inclusive responses of polarized $^{3}$He within the plane wave impulse approximation is briefly reported. A particular emphasys is put on the extraction, from the inclusive responses at the quasielastic peak, of the neutron form factors from feasible experiments.Comment: 6 pages, Latex, 4 Postscript figures. Presented to XVth Conference on "Few-body problems in Physics", Groningen July 1997.To appear in Nucl. Phys.

Li+D Reaction in Pd and Au for 30<E_d<75 keV(I. Nuclear Physics)

Thick target yields of α particles emitted in the ^Li (d, α) ^He reactions in PdLi_x and AuLi_x were measured as a function of the bombarding energy between 30 and 75 keV. It was found that the reaction rate in Pd at lower energies is enhanced strongly over the one predicted by the cross section for the reaction with bare nuclei, but no enhancement is observed in Au. A screening energy is introduced to reproduce the excitation function of the thick target yield for each metal. The deduced value for Pd amounts to 1500±310 eV, whereas it is only 60±150 eV for Au. The enhancement in the Pd case cannot be explained by electron screening alone but suggests the existence of an additional and important mechanism of screening in metal

New determinations of gamma-ray line intensities of the Ep = 550 keV and Ep = 1747 keV resonances of the 13-C(p,gamma)14-N reaction

Gamma-ray angular distributions for the resonances at Ep = 550 keV and 1747 keV of the radiative capture reaction 13-C(p,g)14-N have been measured, using intense proton beams on isotopically pure 13-C targets. Relative intensities for the strongest transitions were extracted with an accuracy of typically five per cent, making these resonances new useful gamma-ray standards for efficiency calibration in the energy range Egamma = 1.6 to 9 MeV.Comment: 17 pages, 6 figures, Nuclear Instruments and Methods, Sec. A, accepte

Investigation of the Neutron Form Factors by Inclusive Quasi-Elastic Scattering of Polarized Electrons off Polarized 3^{3}He: A Theoretical Overview

The theory of quasi-elastic inclusive scattering of polarized leptons off polarized $^3$He is critically reviewed and the origin of different expressions for the polarized nuclear response function appearing in the literature is explained. The sensitivity of the longitudinal asymmetry upon the neutron form factors is thoroughly investigated and the role played by the polarization angle for minimizing the proton contribution is illustrated.Comment: Phys. Rev C in press; 9 figs. (available upon request