Induced Magnetic moments in three-dimensional gauge theories with external magnetic fields

We study the appearance of induced parity-violating magnetic moment, in the presence of external magnetic fields, for even-number of fermion species coupled to dynamical fields in three dimensions. Specifically, we use a SU(2)xU(1) gauge model for dynamical gauge symmetry breaking, which is also proposed recently as a field theoretical model for high-temperature superconductors. By decomposing the fermionic degrees of freedom in terms of Landau levels, we show that, in the effective theory with the lowest Landau levels, a parity-violating magnetic moment interaction is induced by the higher Landau levels when the fermions are massive. The possible relevance of this result for a recently observed phenomenon in high-temperature superconductors is also discussed.Comment: 15 pages revtex, one figure incorporated, References added no other change

Baryons with Two Heavy Quarks as Solitons

Using the chiral soliton model and heavy quark symmetry we study baryons containing two heavy quarks. If there exists a stable (under strong interactions) meson consisting of two heavy quarks and two light ones, then we find that there always exists a state of this meson bound to a chiral soliton and to a chiral anti-soliton, corresponding to a two heavy quark baryon and a baryon containing two heavy anti-quarks and five light quarks, or a ``heptaquark".Comment: 7 pages and 2 postscript figures appended, LaTex, UCI-TR 94-3

Heavy Quark Solitons

We investigate the heavy baryons which arise as solitonic excitations in a ``heavy meson" chiral Lagrangian which includes the light vector particles. It is found that the effect of the light vectors may be substantial. We also present a simple derivation which clearly shows the connection to the Callan-Klebanov approach.Comment: 13 pages; LaTex; SU-4240-532; UR 1306/ER-40685-755 (Minor typos corrected

Energy levels of the soliton--heavy-meson bound states

We investigate the bound states of heavy mesons with finite masses to a classical soliton solution in the Skyrme model. For a given model Lagrangian we solve the equations of motion exactly so that the heavy vector mesons are treated on the same footing as the heavy pseudoscalar mesons. All the energy levels of higher grand spin states as well as the ground state are given over a wide range of the heavy meson masses. We also examine the validity of the approximations used in the literatures. The recoil effect of finite mass soliton is naively estimated.Comment: 24 pages, REVTeX v3.0, 6 figures are available upon request

Heavy Quark Solitons in the Nambu--Jona-Lasinio Model

The Nambu--Jona-Lasinio model (NJL) is extended to incorporate heavy quark spin-symmetry. In this model baryons containing one heavy quark are analyzed as bound-states of light baryons, represented as chiral solitons, and mesons containing one heavy quark. From related studies in Skyrme type models, the ground-state heavy baryon is known to arise for the heavy meson in a P--wave configuration. In the limit of an infinitely large quark mass the heavy meson wave-function is sharply peaked at the center of the chiral soliton. Therefore the bound state equation reduces to an eigenvalue problem for the coefficients of the operators contained in the most general P-wave {\it ansatz} for the heavy meson. Within the NJL model a novel feature arises from the coupling of the heavy meson to the various light quark states. In this respect conceptual differences to Skyrme model calculations are discovered: The strongest bound state is given by a heavy meson configuration which is completely decoupled from the grand spin zero channel of the light quarks.Comment: 16 pages REVTEX, one postscript figure, to appear in Phys. Rev.

Heavy Quark Solitons: Strangeness and Symmetry Breaking

We discuss the generalization of the Callan-Klebanov model to the case of heavy quark baryons. The light flavor group is considered to be $SU(3)$ and the limit of heavy spin symmetry is taken. The presence of the Wess-Zumino-Witten term permits the neat development of a picture , at the collective level, of a light diquark bound to a ``heavy" quark with decoupled spin degree of freedom. The consequences of $SU(3)$ symmetry breaking are discussed in detail. We point out that the $SU(3)$ mass splittings of the heavy baryons essentially measure the ``low energy" physics once more and that the comparison with experiment is satisfactory.Comment: 17 pages, RevTEX. Minor typos corrected and new references adde

On magnetic catalysis in even-flavor QED3

In this paper, we discuss the role of an external magnetic field on the dynamically generated fermion mass in even-flavor QED in three space-time dimensions. Based on some reasonable approximations, we present analytic arguments on the fact that, for weak fields, the magnetically-induced mass increases quadratically with increasing field, while at strong fields one crosses over to a mass scaling logarithmically with the external field. We also confirm this type of scaling behavior through quenched lattice calculations using the non-compact version for the gauge field. Both the zero and finite temperature cases are examined. A preliminary study of the fermion condensate in the presence of magnetic flux tubes on the lattice is also included.Comment: 38 pages latex, 18 figures and a style file (axodraw) incorporated (some clarifying remarks concerning the validity of the approximations made and some references were added correcting an earlier version; no effect on conclusions; version to appear in Phys. Rev. D.

Excited states of heavy baryons in the Skyrme model

We obtain the spectra of excited heavy baryons containing one heavy quark by quantizing the exactly-solved heavy meson bound states to Skyrme soliton. The results are comparable to the recent experimental observations and quark model predictions, and are consistent with the heavy quark spin symmetry. However, somewhat large dependence of the results on the heavy quark mass strongly calls for the incorporation of the soliton-recoil effects.Comment: 24 pages, REVTeX, epsf.sty, 7 figures in uuencoded fil

Treating tobacco dependence in older adults: a survey of primary care clinicians’ knowledge, attitudes, and practice

BACKGROUND: The benefits of smoking cessation among older people are well documented. Despite this, evidence suggests that older smokers are rarely engaged in smoking cessation efforts, and that existing tobacco dependence treatments require further tailoring to the specific needs of older smokers. This study assesses the knowledge, attitudes, and clinical practice of primary care clinicians in relation to addressing tobacco dependence among older people. METHODS: A cross-sectional survey of 427 NHS primary care clinicians in a large English city was conducted using modified version of a previously validated questionnaire. RESULTS: One hundred and seventy one clinicians (40 % response rate) completed the survey. While the majority (90.0 %) of respondents reported enquiring regularly about older patients’ smoking status, just over half (59.1 %) reported providing older patients with smoking cessation support. A lack of awareness in relation to the prevalence and impact of smoking in later life were apparent: e.g. only 47 % of respondents were aware of that approximately 10 life years are lost due to smoking related disease, and only 59 % knew that smoking can reduce the effectiveness of medication prescribed for conditions common in later life. Self-reported attendance at smoking-related training was significantly associated with proactive clinical practice. CONCLUSIONS: There is a need to improve clinicians’ knowledge, in relation to smoking and smoking cessation in older patients and to build clinician confidence in seizing teachable moments. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12875-015-0317-7) contains supplementary material, which is available to authorized users

Excited Heavy Baryons in the Bound State Picture

The orbitally excited heavy quark baryons are studied in the Callan Klebanov bound state model with heavy spin symmetry. First, a compact description of the large $N_c$, infinite heavy quark mass bound state wavefunctions and the collective quantization is given. In order to study the kinematical corrections due to finite masses we motivate an approximate Schrodinger-like equation for the bound state. The effective potential in this equation is compared with the quadratic approximation (spherical harmonic oscillator) to it. This oscillator approximation is seen to be not very accurate. It is noted that the present experimental information cannot be even qualitatively understood with the usual light sector chiral Lagrangian containing only light pseudoscalar mesons. The addition of light vector mesons helps to overcome this problem.Comment: LaTex, 23 pages, SU-4240-586/UCI-TR 94-3