The Coester Line in Relativistic Mean Field Nuclear Matter

The Walecka model contains essentially two parameters that are associated with the Lorentz scalar (S) and vector (V) interactions. These parameters are related to a two-body interaction consisting of S and V, imposing the condition that the two-body binding energy is fixed. We have obtained a set of different values for the nuclear matter binding energies at equilibrium densities. We investigated the existence of a linear correlation between $B_N$ and $\rho_0$, claimed to be universal for nonrelativistic systems and usually known as the Coester line, and found an approximate linear correlation only if $V?S$ remains constant. It is shown that the relativistic content of the model, which is related to the strength of $V?S$, is responsible for the shift of the Coester line to the empirical region of nuclear matter saturation.Comment: 7 pages, 5 figure

Four-boson scale near a Feshbach resonance

We show that an independent four-body momentum scale $\mu_{(4)}$ drives the tetramer binding energy for fixed trimer energy (or three-body scale $\mu_{(3)}$) and large scattering length ($a$). The three- and four-body forces from the one-channel reduction of the atomic interaction near a Feshbach resonance disentangle $\mu_{(4)}$ and $\mu_{(3)}$. The four-body independent scale is also manifested through a family of Tjon-lines, with slope given by $\mu_{(4)}/\mu_{(3)}$ for $a^{-1}=0$. There is the possibility of a new renormalization group limit cycle due to the new scale

Phase transition of the nucleon-antinucleon plasma at different ratios

We investigate phase transitions for the Walecka model at very high temperatures. As is well known, depending on the parametrization of this model and for the particular case of a zero chemical potential ($\mu$), a first order phase transition is possible \cite{theis}. We investigate this model for the case in which $\mu \ne 0$. It turns out that, in this situation, phases with different values of antinucleon-nucleon ratios and net baryon densities may coexist. We present the temperature versus antinucleon-nucleon ratio as well as the temperature versus the net baryon density for the coexistence region. The temperature versus chemical potential phase diagram is also presented.Comment: 5 pages, 8 figure

Nucleon-nucleon scattering within a multiple subtractive renormalization approach

A methodology to renormalize the nucleon-nucleon interaction, using a recursive multiple subtraction approach to construct the kernel of the scattering equation, is presented. We solve the subtracted scattering equation with the next-leading-order (NLO) and next-to-next-leading-order (NNLO) interactions. The results are presented for all partial waves up to $j=2$, fitted to low-energy experimental data. In our renormalizaton group invariant method, when introducing the NLO and NNLO interactions, the subtraction energy emerges as a renormalization scale and the momentum associated with it comes to be about the QCD scale ($\Lambda_{QCD}$), irrespectively to the partial wave.Comment: Final versio

Form factors in the Bullough-Dodd related models: The Ising model in a magnetic field

We consider particular modification of the free-field representation of the form factors in the Bullough-Dodd model. The two-particles minimal form factors are excluded from the construction. As a consequence, we obtain convenient representation for the multi-particle form factors, establish recurrence relations between them and study their properties. The proposed construction is used to obtain the free-field representation of the lightest particles form factors in the $\Phi_{1,2}$ perturbed minimal models. As a significant example we consider the Ising model in a magnetic field. We check that the results obtained in the framework of the proposed free-field representation are in agreement with the corresponding results obtained by solving the bootstrap equations.Comment: 20 pages; v2: some misprints, textual inaccuracies and references corrected; some references and remarks adde

Isospin Constraints on the Parametric Coupling Model for Nuclear Matter

We make use of isospin constraints to study the parametric coupling model and the properties of asymmetric nuclear matter. Besides the usual constraints for nuclear matter - effective nucleon mass and the incompressibility at saturation density - and the neutron star constraints - maximum mass and radius - we have studied the properties related with the symmetry energy. These properties have constrained to a small range the parameters of the model. We have applied our results to study the thermodynamic instabilities in the liquid-gas phase transition as well as the neutron star configurations.Comment: 11 pages, 10 figure

Integrable structures in LGTs near the deconfinement transition

In this contribution we review some recent results about the emergence of 2D integrable systems in 3D Lattice Gauge Theories near the deconfinement transition. We focus on some concrete examples involving the flux tube thickness, the ratio of k-string tensions and Polyakov loops correlators in various models.Comment: 8 pages, Poster contribution to the XXVII International Symposium on Lattice Field Theory, July 26-31, 2009, Peking University, Beijing, Chin

Naturalistic study on the effectiveness of psycho-oncological interventions in cancer patients and their partners

Background: There is evidence for the efficacy of psycho-oncological interventions (POI) in randomized controlled trials for cancer patients. Our objective was to explore, under naturalistic conditions (using propensity score matching), whether POI are effective to decrease anxiety, depression, distress and overall psychopathological symptoms within cancer patients and their partners. Methods: This study was conducted in the Oncology and Hematology Center of a University clinic in Switzerland with a group of 186 patients and 117 partners. Outcome measures of mental health were the Hospital Anxiety and Depression Scale and the Symptom Checklist (SCL-9-K). Repeated-measures ANOVAs were used to analyze change over time and group effects between individuals with POI vs. without POI. Results: Highly distressed patients and their partners participating in POI reported better mental health over time. Among moderately distressed patients, a decrease over time emerged in depression and distress independent of POI. No effectiveness of POI could be demonstrated in moderately distressed patients and partners. Conclusion: Most of the highly distressed patients receive additional POI and therefore conclusions about the efficacy of POI are difficult. For moderately distressed individuals, POI as implemented in Switzerland does not improve mental health in such patients and their partners, which may be caused by very time limited POI treatments. Studies with more intense POI treatments are neede