The longitudinal response function of the deuteron in chiral effective field theory

We use chiral effective field theory (EFT) to make predictions for the longitudinal electromagnetic response function of the deuteron, f_L, which is measured in d(e,e'N) reactions. In this case the impulse approximation gives the full chiral EFT result up to corrections that are of O(P^4) relative to leading. By varying the cutoff in the chiral EFT calculations between 0.6 and 1 GeV we conclude that the calculation is accurate to better than 10 % for values of q^2 within 4 fm^{-2} of the quasi-free peak, up to final-state energies E_{np}=60 MeV. In these regions chiral EFT is in reasonable agreement with predictions for f_L obtained using the Bonn potential. We also find good agreement with existing experimental data on f_L, albeit in a more restricted kinematic domain.Comment: 33 pages, 10 figures. Accepted for publication in EPJA, with a few further correction

Extra dimensions, SN1987a, and nucleon-nucleon scattering data

One of the strongest constraints on the existence of large, compact, "gravity-only" dimensions comes from SN1987a. If the rate of energy loss into these putative extra dimensions is too high, then the neutrino pulse from the supernova will differ from that actually seen. The dominant mechanism for the production of Kaluza-Klein gravitons and dilatons in the supernova is via gravistrahlung and dilastrahlung from the nucleon-nucleon system. In this paper we compute the rates for these processes in a model-independent way using low-energy theorems which relate the emissivities to the measured nucleon-nucleon cross section. This is possible because for soft gravitons and dilatons the leading contribution to the energy-loss rate is from graphs in which the gravitational radiation is produced from external nucleon legs. Previous calculations neglected these mechanisms. We re-evaluate the bounds on toroidally-compactified "gravity-only" dimensions (GODs), and find that consistency with the observed SN1987a neutrino signal requires that if there are two such dimensions then their radius must be less than 1 micron.Comment: 24 pages, 5 figures. Minor changes to first two paragraphs of introductio

Central pain mechanisms in the rheumatic diseases: Future directions

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/96384/1/37739_ftp.pd

Towards being genuinely smart : ‘isothermally-responsive’ polymers as versatile, programmable scaffolds for biologically-adaptable materials

Responsive polymers have found diverse application across polymer, biomaterials, medical, sensing and engineering fields. Despite many years of study, this has focussed mainly on those polymers which undergo thermally-induced changes – either a lower or upper critical solution temperature. To rival the adaptability of Nature's macromolecules, polymers must respond in a ‘smarter’ way to other triggers such as enzymes, biochemical gradients, ion concentration or metabolites, to name a few. Here we review the concept of ‘isothermal’ responses where core thermoresponsive polymers are chemically engineered such that they undergo their useful response (such as coil-globule transition, cell uptake or cargo release) but at constant temperature. This is achieved by consideration of their phase diagram where solubility can be changed by small structural changes to the end-group, side-chain/substituents or through main chain modification/binding. The current state-of-the-art is summarised here

From Hadrons to Nuclei: Crossing the Border

The study of nuclei predates by many years the theory of quantum chromodynamics. More recently, effective field theories have been used in nuclear physics to ``cross the border'' from QCD to a nuclear theory. We are now entering the second decade of efforts to develop a perturbative theory of nuclear interactions using effective field theory. This work describes the current status of these efforts.Comment: 141 pages, 58 figs, latex. To appear in the Boris Ioffe Festschrift, ed. by M. Shifman, World Scientifi

Chiral effective theory predictions for deuteron form factor ratios at low Q^2

We use chiral effective theory to predict the deuteron form factor ratio G_C/G_Q as well as ratios of deuteron to nucleon form factors. These ratios are calculated to next-to-next-to-leading order. At this order the chiral expansion for the NN isoscalar charge operator (including consistently calculated 1/M corrections) is a parameter-free prediction of the effective theory. Use of this operator in conjunction with NLO and NNLO chiral effective theory wave functions produces results that are consistent with extant experimental data for Q^2 < 0.35 GeV^2. These wave functions predict a deuteron quadrupole moment G_Q(Q^2=0)=0.278-0.282 fm^2-with the variation arising from short-distance contributions to this quantity. The variation is of the same size as the discrepancy between the theoretical result and the experimental value. This motivates the renormalization of G_Q via a two-nucleon operator that couples to quadrupole photons. After that renormalization we obtain a robust prediction for the shape of G_C/G_Q at Q^2 < 0.3 GeV^2. This allows us to make precise, model-independent predictions for the values of this ratio that will be measured at the lower end of the kinematic range explored at BLAST. We also present results for the ratio G_C/G_M.Comment: 31 pages, 7 figure