Low-energy cross section data for 86 charged-particle induced reactions involving light (1 ⩽ Z ⩽ 14), mostly stable, nuclei are compiled. The corresponding Maxwellian-averaged thermonuclear reaction ...rates of relevance in astrophysical plasmas at temperatures in the range from 10
6 K to 10
10 K are calculated. These evaluations assume either that the target nuclei are in their ground state, or that the target states are thermally populated following a Maxwell-Boltzmann distribution, except in some cases involving isomeric states.
Adopted values complemented with lower and upper limits of the rates are presented in tabular form. Analytical approximations to the adopted rates, as well as to the inverse/direct rate ratios, are provided.
The uncertainties in neutron star (NS) radii and crust properties due to our limited knowledge of the equation of state (EOS) are quantitatively analysed. We first demonstrate the importance of a ...unified microscopic description for the different baryonic densities of the star. If the pressure functional is obtained matching a crust and a core EOS based on models with different properties at nuclear matter saturation, the uncertainties can be as large as $\sim 30\%$ for the crust thickness and $4\%$ for the radius. Necessary conditions for causal and thermodynamically consistent matchings between the core and the crust are formulated and their consequences examined. A large set of unified EOS for purely nucleonic matter is obtained based on 24 Skyrme interactions and 9 relativistic mean-field nuclear parametrizations. In addition, for relativistic models 17 EOS including a transition to hyperonic matter at high density are presented. All these EOS have in common the property of describing a $2\;M_\odot$ star and of being causal within stable NS. A span of $\sim 3$ km and $\sim 4$ km is obtained for the radius of, respectively, $1.0\;M_\odot$ and $2.0\;M_\odot$ star. Applying a set of nine further constraints from experiment and ab-initio calculations the uncertainty is reduced to $\sim 1$ km and $2$ km, respectively. These residual uncertainties reflect lack of constraints at large densities and insufficient information on the density dependence of the EOS near the nuclear matter saturation point. The most important parameter to be constrained is shown to be the symmetry energy slope $L$ which exhibits a linear correlation with the stellar radius, particularly for masses $\sim 1.0\;M_\odot$. Potential constraints on $L$, the NS radius and the EOS from observations of thermal states of NS are also discussed. Abriged
Aims. In this work, we study the structure of neutron stars under the effect of a poloidal magnetic field and determine the limiting largest magnetic field strength that induces a deformation such ...that the ratio between the polar and equatorial radii does not exceed 2%. We consider that, under these conditions, the description of magnetic neutron stars in the spherical symmetry regime is still satisfactory. Methods. We described different compositions of stars (nucleonic, hyperonic, and hybrid) using three state-of-the-art relativistic mean field models (NL3ωρ, MBF, and CMF, respectively) for the microscopic description of matter, all in agreement with standard experimental and observational data. The structure of stars was described by the general relativistic solution of both Einstein’s field equations assuming spherical symmetry and Einstein-Maxwell’s field equations assuming an axi-symmetric deformation. Results. We find a limiting magnetic moment on the order of 2 × 1031 Am2, which corresponds to magnetic fields on the order of 1016 G at the surface and 1017 G at the center of the star, above which the deformation due to the magnetic field is above 2%, and therefore not negligible. We show that the intensity of the magnetic field developed in the star depends on the equation of state (EoS), and, for a given baryonic mass and fixed magnetic moment, larger fields are attained with softer EoS. We also show that the appearance of exotic degrees of freedom, such as hyperons or a quark core, is disfavored in the presence of a very strong magnetic field. As a consequence, a highly magnetized nucleonic star may suffer an internal conversion due to the decay of the magnetic field, which could be accompanied by a sudden cooling of the star or a gamma ray burst.
Despite the existence of several risk scores, the accurate prediction of the prognosis in pulmonary embolism (PE) remains a challenge. The Global Registry of Acute Coronary Events (GRACE) risk score ...has a high diagnostic performance for adverse outcomes in acute coronary syndrome. We aimed to assess the applicability and extend the use of the GRACE risk score to PE. A case-control study of 206 consecutive patients admitted with PE was performed. The GRACE, Geneva, Simplified Pulmonary Embolism Severity Index, Shock Index, and European Society of Cardiology risk scores were tested for the prediction of the primary end point: all-cause 30-day mortality. Comparisons between GRACE and the other risk scores were performed using receiver operating characteristic area under the curve and the integrated discrimination improvement index. All-cause 30-day mortality was observed in 18.9% of the patients. Unlike the other classifications, no adverse outcomes were observed in patients classified as low risk using the GRACE risk score (100% negative predictive value for GRACE risk score ≤113). The GRACE score showed greater discriminative performance than the Geneva score (area under the curve 0.623, 95% confidence interval CI 0.53 to 0.71), Shock Index (area under the curve 0.639, 95% CI 0.55 to 0.73), European Society of Cardiology (area under the curve 0.662, 95% CI 0.57 to 0.76), and Simplified Pulmonary Embolism Severity Index (area under the curve 0.705, 95% CI 0.61 to 0.80), although statistical significance was not reached. The integrated discrimination improvement index suggested a more appropriate risk classification with the GRACE score. In conclusion, our results have demonstrated that the GRACE risk score can accurately predict 30-day mortality in patients admitted for acute PE. Compared to previously proposed PE prediction rules, the GRACE risk score presented improved overall risk classification.
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