Gluonic Excitations and Experimental Hall-D at Jefferson Lab

A new tagged photon beam facility is being constructed in experimental Hall-D at Jefferson Lab as a part of the 12 GeV upgrade program. The 9 GeV linearly-polarized photon beam will be produced via coherent Bremsstrahlung using the CEBAF electron beam, incident on a diamond radiator. The GlueX experiment in Hall-D will use this photon beam to search for and study the pattern of gluonic excitations in the meson spectrum produced through photoproduction reactions with a liquid hydrogen target. Recent lattice QCD calculations predict a rich spectrum of hybrid mesons, that are formed by exciting the gluonic field that couples the quarks. A subset of these hybrid mesons are predicted to have exotic quantum numbers which cannot be formed from a simple $q\bar{q}$ pair, and thus provide an ideal laboratory for testing QCD in the confinement regime. In these proceedings the status of the construction and installation of the GlueX detector will be presented, in addition to simulation results for some reactions of interest in hybrid meson searches.Comment: 5 pages, 4 figures, 1 table, contribution to the proceedings of XXII. International Workshop on Deep-Inelastic Scattering and Related Subjects, 28 Apr - 2 May, 2014, Warsaw, Polan

U(1) gauge invariance from open string field theory

The naive low energy effective action of the tachyon and the U(1) gauge field obtained from string field theory does not correspond to the world volume action of unstable branes in bosonic string theory. We show that there exists a field redefinition which relates the gauge field and the tachyon of the string field theory action to the fields in the world volume action of unstable branes. We identify a string gauge symmetry which corresponds to the U(1) gauge transformation. This is done to the first non-linear order in the fields. We examine the vector fluctuations at the tachyon condensate till level (4,8).Comment: Section on transverse photon at tachyon condensate added, 23 pages, Uses JHEP.cl

A Community Schools Approach to Accessing Services and Improving Neighborhood Outcomes in Manchester, NH

This brief uses data collected by the Manchester Health Department in 2013 and analyzed by the Carsey School of Public Policy in the Bakersville, Beech Street, and Gossler Park neighborhoods in Manchester, New Hampshire, to provide information about how barriers to various dimensions of well-being differ by place and also across race/ethnicity, foreign-born status, and age. Survey data and focus groups also gave residents a voice in the implementation of the Manchester Community Schools Project—a partnership between the Manchester Health Department, city elementary schools, philanthropists, neighborhood residents, and several nonprofit agencies—to improve and enhance educational achievement, economic well-being, access to health care services, healthy behaviors, social connectedness, safety, and living environments. A key element of this project is to make elementary schools in the Bakersville, Beech Street, and Gossler Park neighborhoods centerpieces of community life for all residents, not just those with children. Author Justin Young reports that one-quarter of residents surveyed in 2013 in the Manchester neighborhoods of Bakersville, Beech Street, and Gossler Park say that difficulty in finding services is a major hindrance, especially to economic stability, health, and social connectedness. Focus group data suggest that the city’s foreign-born residents, especially Hispanics, have the most trouble finding and accessing services. Cost is an obstacle to accessing health care services, and older and younger focus group participants, as well as immigrants, say the cost of transportation is a barrier to accessing services. He concludes that the neighborhood in which one lives shapes a variety of outcomes related to well-being, and that a place-based approach like the community schools model can improve outcomes not only for residents of the Bakersville, Beech Street, and Gossler Park areas but for all Manchester residents

The STAR W Program at RHIC

The production of $W$ bosons in polarized $p+p$ collisions at RHIC provides an excellent tool to probe the proton's sea quark distributions. At leading order $W^{-(+)}$ bosons are produced in $\bar{u}+d\,(\bar{d}+u)$ collisions, and parity-violating single-spin asymmetries measured in longitudinally polarized $p+p$ collisions give access to the flavor-separated light quark and antiquark helicity distributions. In this proceedings we report preliminary results for the single-spin asymmetry, $A_L$ from data collected in 2012 by the STAR experiment at RHIC with an integrated luminosity of 72 pb$^{-1}$ at $\sqrt{s}=510$ GeV and an average beam polarization of 56%.Comment: Proceedings of the 3rd Workshop on the QCD Structure of the Nucleon (QCD-N' 2012

Infra-red dynamics of D1-branes at the conifold

We study the infra-red dynamics of D1-branes at the conifold. We show using methods developed to study the infra-red dynamics of (4,4) theories, the infra-red degrees of freedom of the (2,2) theory of a single D1-brane at the conifold is that of a linear dilaton with background charge of $\sqrt{2}$ and a compact scalar. The gauge theory of $N$ D1-branes at the conifold is used to formulate the matrix string in the conifold background.Comment: 20 pages, latex, some clarifications added, version to appear in JHE