209 research outputs found
Test of OPE and OGE through mixing angles of negative parity N* resonances in electromagnetic transitions
In this report, by using the mixing angles of one-gluon-exchange model(OGE)
and one-pion-exchange model(OPE), and by using the electromagnetic Hamiltonian
of Close and Li, we calculate the amplitudes of L=1 N* resonances for
photoproduction and electroproduction. The results are compared to experimental
data. It's found that the data support OGE, not OPE.Comment: 5 pages, Latex, 1 figure, accepted by Phys.Rev.
Sound archaeology: terminology, Palaeolithic cave art and the soundscape
This article is focused on the ways that terminology describing the study of music and sound within archaeology has changed over time, and how this reflects developing methodologies, exploring the expectations and issues raised by the use of differing kinds of language to define and describe such work. It begins with a discussion of music archaeology, addressing the problems of using the term âmusicâ in an archaeological context. It continues with an examination of archaeoacoustics and acoustics, and an emphasis on sound rather than music. This leads on to a study of sound archaeology and soundscapes, pointing out that it is important to consider the complete acoustic ecology of an archaeological site, in order to identify its affordances, those possibilities offered by invariant acoustic properties. Using a case study from northern Spain, the paper suggests that all of these methodological approaches have merit, and that a project benefits from their integration
On the Particle Data Group evaluation of Psi' and chi_c Branching Ratios
I propose a new evaluation of and branching ratios
which avoids the correlations affecting the current Particle Data Group
evaluation.
These correlations explain the apparent technique-dependent discrepancies
between the available determinations of the
and under the hypotesis that the current
values of the branching ratios are
overestimated.
In the process I also noticed that Particle Data Group has not restated many
of the older measurements, when necessary, for the new value of , which significantly affects the evaluation of some
relevant and exclusive branching ratios.Comment: 13 pages. Revised version. Submitted to Phys. Rev.
Radiative decays: a new flavour filter
Radiative decays of the orbital excitations of the ,
and to the scalars , and are shown to
provide a flavour filter, clarifying the extent of glueball mixing in the
scalar states. A complementary approach to the latter is provided by the
radiative decays of the scalar mesons to the ground-state vectors ,
and . Discrimination among different mixing scenarios is strong.Comment: 12 pages, 1 table, 0 figure
Quark-antiquark potential with retardation and radiative contributions and the heavy quarkonium mass spectra
The charmonium and bottomonium mass spectra are calculated with the
systematic account of all relativistic corrections of order v^2/c^2 and the
one-loop radiative corrections. Special attention is paid to the contribution
of the retardation effects to the spin-independent part of the quark-antiquark
potential, and a general approach to accounting for retardation effects in the
long-range (confining) part of the potential is presented. A good fit to
available experimental data on the mass spectra is obtained.Comment: 20 pages, revtex, 2 Postscript figure
Living biointerfaces based on non-pathogenic bacteria to direct cell differentiation
Genetically modified Lactococcus lactis, non-pathogenic bacteria expressing the FNIII7-10 fibronectin fragment as a protein membrane have been used to create a living biointerface between synthetic materials and mammalian cells. This FNIII7-10 fragment comprises the RGD and PHSRN sequences of fibronectin to bind α5ÎČ1 integrins and triggers signalling for cell adhesion, spreading and differentiation. We used L. lactis strain to colonize material surfaces and produce stable biofilms presenting the FNIII7-10 fragment readily available to cells. Biofilm density is easily tunable and remains stable for several days. Murine C2C12 myoblasts seeded over mature biofilms undergo bipolar alignment and form differentiated myotubes, a process triggered by the FNIII7-10 fragment. This biointerface based on living bacteria can be further modified to express any desired biochemical signal, establishing a new paradigm in biomaterial surface functionalisation for biomedical applications
Clubbing masculinities: Gender shifts in gay men's dance floor choreographies
This is an Author's Accepted Manuscript of an article published in Journal of Homosexuality, 58(5), 608-625, 2011 [copyright
Taylor & Francis], available online at: http://www.tandfonline.com/10.1080/00918369.2011.563660This article adopts an interdisciplinary approach to understanding the intersections of gender, sexuality, and dance. It examines the expressions of sexuality among gay males through culturally popular forms of club dancing. Drawing on political and musical history, I outline an account of how gay men's gendered choreographies changed throughout the 1970s, 80s, and 90s. Through a notion of âtechnologies of the body,â I situate these developments in relation to cultural levels of homophobia, exploring how masculine expressions are entangled with and regulated by musical structures. My driving hypothesis is that as perceptions of cultural homophobia decrease, popular choreographies of gay men's dance have become more feminine in expression. Exploring this idea in the context of the first decade of the new millennium, I present a case study of TigerHeat, one of the largest weekly gay dance club events in the United States
Variational Estimation of the Wave Function at Origin for Heavy Quarkonium
The wave function at the origin (WFO) is an important quantity in studying
many physical problems concerning heavy quarkonia. However, when one used the
variational method with fewer parameters, in general, the deviation of
resultant WFO from the "accurate" solution was not well estimated. In this
paper, we discuss this issue by employing several potential forms and trial
wave functions in detail and study the relation between WFO and the reduced
mass.Comment: 17 pages, .zip file of the LATEX2
Understood at Last?: A Memetic Analysis of Beethovenâs âBloody Fistâ
As a singular moment in the western canon, the opening of the recapitulation in the first movement of Beethovenâs Ninth Symphony has prompted a variety of structural and expressive readings. This paper explores its intertextual connections with Mozartâs Don Giovanni from a memetic perspective, outlining certain extra musical interpretations, including some related to Susan McClaryâs controversial reading of the passage, one might infer from the strong musical connections
Heavy quarkonium: progress, puzzles, and opportunities
A golden age for heavy quarkonium physics dawned a decade ago, initiated by
the confluence of exciting advances in quantum chromodynamics (QCD) and an
explosion of related experimental activity. The early years of this period were
chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in
2004, which presented a comprehensive review of the status of the field at that
time and provided specific recommendations for further progress. However, the
broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles
could only be partially anticipated. Since the release of the YR, the BESII
program concluded only to give birth to BESIII; the -factories and CLEO-c
flourished; quarkonium production and polarization measurements at HERA and the
Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the
deconfinement regime. All these experiments leave legacies of quality,
precision, and unsolved mysteries for quarkonium physics, and therefore beg for
continuing investigations. The plethora of newly-found quarkonium-like states
unleashed a flood of theoretical investigations into new forms of matter such
as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the
spectroscopy, decays, production, and in-medium behavior of c\bar{c}, b\bar{b},
and b\bar{c} bound states have been shown to validate some theoretical
approaches to QCD and highlight lack of quantitative success for others. The
intriguing details of quarkonium suppression in heavy-ion collisions that have
emerged from RHIC have elevated the importance of separating hot- and
cold-nuclear-matter effects in quark-gluon plasma studies. This review
systematically addresses all these matters and concludes by prioritizing
directions for ongoing and future efforts.Comment: 182 pages, 112 figures. Editors: N. Brambilla, S. Eidelman, B. K.
Heltsley, R. Vogt. Section Coordinators: G. T. Bodwin, E. Eichten, A. D.
Frawley, A. B. Meyer, R. E. Mitchell, V. Papadimitriou, P. Petreczky, A. A.
Petrov, P. Robbe, A. Vair
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