5,028 research outputs found
Low-energy expansion of the pion-nucleon Lagrangian
The renormalized pion-nucleon Lagrangian is calculated to O(p^3) in heavy
baryon chiral perturbation theory. By suitably chosen transformations of the
nucleon field, the Lagrangian is brought to a standard form.Comment: 10 pages, Latex, 1 figure in uuencoded postscript file embedded with
epsfig.st
Curvature estimates for Weingarten hypersurfaces in Riemannian manifolds
We prove curvature estimates for general curvature functions. As an
application we show the existence of closed, strictly convex hypersurfaces with
prescribed curvature , where the defining cone of is \C_+. is only
assumed to be monotone, symmetric, homogeneous of degree 1, concave and of
class C^{m,\al}, .Comment: 9 pages, v2:final version, to be publishe
<VAP> Green Function in the Resonance Region
We analyse the three-point function of vector, axial-vector and
pseudoscalar currents. In the spirit of large N_C, a resonance dominated Green
function is confronted with the leading high-energy behaviour from the operator
product expansion. The matching is shown to be fully compatible with a chiral
resonance Lagrangian and it allows to determine some of the chiral low-energy
constants of O(p^6).Comment: 13 pages, 2 figures. Published version. Results and conclusions
unchange
Anatomy of Mixing-Induced CP Asymmetries in Left-Right-Symmetric Models with Spontaneous CP Violation
We investigate the pattern of CP violation in K, B_d and B_s mixing in a
symmetrical SU(2)_R x SU(2)_L x U(1) model with spontaneous CP violation. We
calculate the phases of the left and right quark mixing matrices beyond the
small phase approximation and perform a careful analysis of all relevant
restrictions on the model's parameters from Delta m_K, Delta m_B, epsilon,
epsilon'/epsilon and the CP asymmetry in B->J/psi K_S. We find that, with
current experimental data, the mass of the right-handed charged gauge boson,
M2, is restricted to be in the range 2.75 to 13 TeV and the mass of the
flavour-changing neutral Higgs boson, MH, in 10.2 to 14.6 TeV. This means in
particular that the decoupling limit M2, MH -> infinity is already excluded by
experiment. We also find that the model favours opposite signs of epsilon and
sin 2beta and is excluded if sin 2beta > 0.1.Comment: 33 pages Latex with 11 Postscript-Figures (included
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The phenomenology of emotion in depressed young adolescents.
Depressive affect and depressive disorders have been shown to increase in the transition from childhood to early adolescence. Furthermore, although Major Depression is classified as an affective disorder and many have asserted the importance that knowledge about emotions holds for understanding the organization, etiology, neurobiology, and treatment of depression, empirical investigation has been lacking. This is particularly true as regards adolescence. The current study explored the subjective experience of emotions, with attention also to emotional expression, associated with depression in groups of 39 psychiatric inpatients and 22 non-clinical control young adolescents. Measures included a self-report measure of depressive symptomatology, the Childhood Depression Inventory (CDI), and a self-report measure of the frequency of experience of individual emotions, the Differential Emotions Scale-IV (DES-IV). Two new emotions scales, Loved and Detached, were added to the DES-IV. There also was a video mood induction procedure accompanied by verbal report of immediate emotional state and detailed analysis of emotional facial expressions using the AFFEX system. Results were analyzed considering differences in depression level and gender. Depressed subjects scored significantly higher on a Dysphoria factor, most saliently comprised of Inward Hostility and Shame but also including Shyness, Fear and Sadness, and significantly lower on a Joy/Loved factor. The depressed subjects also reported being more aware of their emotions. Regarding emotional expression, depressed subjects showed a higher frequency of negative emotions (anger, sadness, disgust) and a lower frequency of joy than their non-depressed counterparts. There were no depression-related differences in self-report of emotional state in response to the video mood induction procedure, though males reported being happier than females. The relationship between emotional experience and emotional expression was stable over all depression level by gender groupings with the exception of highly depressed males. Overall, there were large gender-related differences in the organization of emotions associated with depression, with relationships for males characterized as fragmented. Study results are discussed in reference to research on emotions and depression in children and adults, normal adolescent emotional development, and adolescent development in other domains, most notably the self-concept
Comment on soft-pion emission in DVCS
The soft-pion theorem for pion production in deeply virtual Compton
scattering, derived by Guichon, Mosse and Vanderhaegen, is shown to be
consistent with chiral perturbation theory. Chiral symmetry requires that the
nonsinglet operators corresponding to spin-independent and spin-dependent
parton distributions have the same anomalous dimensions in cases where those
operators are related by chiral transformations. In chiral perturbation theory,
their scale-dependences can thus be absorbed in the coefficents of the
corresponding effective operators, without affecting their chiral structures.Comment: 2 pages, RevTe
Long distance contribution to decay and terms in CHPT
The long distance contribution to is
calculated using chiral perturbation theory. The leading contribution comes
from tree terms. The branching ratio of the long distance
contribution is found to be of order smaller than the short distance
contributions.Comment: 12 pages, 1 figure (available upon request
Role of Scalar Meson Resonances in $K_{L}^{0} \rightarrow \pi^{0} \gamma \gamma Decay
Corrections to decay induced by
scalar meson exchange are studied within chiral perturbation theory. In spite
of bad knowledge of scalar-mesons parameters, the calculated branching ratio
can be changed by a few percent.Comment: 18 pages of text, 2 figures (available upon request); preprint
IJS-TP-16-94 , TUM-T31-63-94
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