5,919 research outputs found

    Two-Loop O(αt2){\cal O}(\alpha_t^2) Corrections to the Neutral Higgs Boson Masses in the CP-Violating NMSSM

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    We present our calculation of the two-loop corrections of O(αt2){\cal O}(\alpha_t^2) to the neutral Higgs boson masses of the CP-violating Next-to-Minimal Supersymmetric extension of the Standard Model (NMSSM). The calculation is performed in the Feynman diagrammatic approach in the gaugeless limit at vanishing external momentum. We apply a mixed DR\overline{\mathrm{DR}}-on-shell (OS) renormalization scheme for the NMSSM input parameters. Furthermore, we exploit a DR\overline{\mathrm{DR}} as well as an OS renormalization in the top/stop sector. The corrections are implemented in the Fortran code NMSSMCALC for the calculation of the Higgs spectrum both in the CP-conserving and CP-violating NMSSM. The code also provides the Higgs boson decays including the state-of-the-art higher-order corrections. The corrections computed in this work improve the already available corrections in NMSSMCALC which are the full one-loop corrections without any approximation and the two-loop O(αtαs){\cal O}(\alpha_t \alpha_s) corrections in the gaugeless limit and at vanishing external momentum. Depending on the chosen parameter point, we find that the O(αtαs+αt2){\cal O}(\alpha_t \alpha_s + \alpha_t^2) corrections add about 4-7% to the one-loop mass of the SM-like Higgs boson for DR\overline{\mathrm{DR}} renormalization in the top/stop sector and they reduce the mass by about 6-9% if OS renormalization is applied. For an estimate of the theoretical uncertainty we vary the renormalization scale and change the renormalization scheme and show that care has to be taken in the corresponding interpretation

    Probing the isovector transition strength of the low-lying nuclear excitations induced by inverse kinematics proton scattering

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    A compact approach based on the folding model is suggested for the determination of the isoscalar and isovector transition strengths of the low-lying (ΔS=ΔT=0\Delta S=\Delta T=0) excitations induced by inelastic proton scattering measured with exotic beams. Our analysis of the recently measured inelastic 18,20^{18,20}O+p scattering data at Elab=30E_{\rm lab}=30 and 43 MeV/nucleon has given for the first time an accurate estimate of the isoscalar β0\beta_0 and isovector β1\beta_1 deformation parameters (which cannot be determined from the (p,p') data alone by standard methods) for 21+^+_1 and 313^-_1 excited states in 18,20^{18,20}O. Quite strong isovector mixing was found in the 21+^+_1 inelastic 20^{20}O+p scattering channel, where the strength of the isovector form factor F1F_1 (prototype of the Lane potential) corresponds to a β1\beta_1 value almost 3 times larger than β0\beta_0 and a ratio of nuclear transition matrix elements Mn/Mp4.2M_n/M_p\simeq 4.2.Comment: 5 pages, 3 figure

    Neutron transition strengths of 21+2^+_1 states in the neutron rich Oxygen isotopes determined from inelastic proton scattering

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    A coupled-channel analysis of the 18,20,22^{18,20,22}O(p,p)(p,p') data has been performed to determine the neutron transition strengths of 21+^+_1 states in Oxygen targets, using the microscopic optical potential and inelastic form factor calculated in the folding model. A complex density- and \emph{isospin} dependent version of the CDM3Y6 interaction was constructed, based on the Brueckner-Hatree-Fock calculation of nuclear matter, for the folding model input. Given an accurate isovector density dependence of the CDM3Y6 interaction, the isoscalar (δ0\delta_0) and isovector (δ1\delta_1) deformation lengths of 21+^+_1 states in 18,20,22^{18,20,22}O have been extracted from the folding model analysis of the (p,p)(p,p') data. A specific NN-dependence of δ0\delta_0 and δ1\delta_1 has been established which can be linked to the neutron shell closure occurring at NN approaching 16. The strongest isovector deformation was found for 21+^+_1 state in 20^{20}O, with δ1\delta_1 about 2.5 times larger than δ0\delta_0, which indicates a strong core polarization by the valence neutrons in 20^{20}O. The ratios of the neutron/proton transition matrix elements (Mn/MpM_n/M_p) determined for 21+^+_1 states in 18,20^{18,20}O have been compared to those deduced from the mirror symmetry, using the measured B(E2)B(E2) values of 21+^+_1 states in the proton rich 18^{18}Ne and 20^{20}Mg nuclei, to discuss the isospin impurity in the 21+2^+_1 excitation of the A=18,T=1A=18,T=1 and A=20,T=2A=20,T=2 isobars.Comment: Version accepted for publication in Physical Review

    Pair formation and collapse in imbalanced Fermion populations with unequal masses

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    We present an exact Quantum Monte Carlo study of the effect of unequal masses on pair formation in Fermionic systems with population imbalance loaded into optical lattices. We have considered three forms of the attractive interaction and find in all cases that the system is unstable and collapses as the mass difference increases and that the ground state becomes an inhomogeneous collapsed state. We also address the question of canonical vs grand canonical ensemble and its role, if any, in stabilizing certain phases

    GEODYN programmer's guide, volume 2, part 2

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    A computer program for executive control routine for orbit integration of artificial satellites is presented. At the beginning of each arc, the program initiates required constants as well as the variational partials at epoch. If epoch needs to be reset to a previous time, the program negates the stepsize, and calls for integration backward to the desired time. After backward integration is completed, the program resets the stepsize to the proper positive quantity

    Analytical approximation for the sphere-sphere Coulomb potential

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    A simple analytical expression, which closely approximates the Coulomb potential between two uniformly charged spheres, is presented. This expression can be used in the optical potential semiclassical analyses which require that the interaction be analytic on and near the real r-axis.Comment: 4 pages including 3 figures and 1 tabl

    Asymptotic Behavior of Ext functors for modules of finite complete intersection dimension

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    Let RR be a local ring, and let MM and NN be finitely generated RR-modules such that MM has finite complete intersection dimension. In this paper we define and study, under certain conditions, a pairing using the modules \Ext_R^i(M,N) which generalizes Buchweitz's notion of the Herbrand diference. We exploit this pairing to examine the number of consecutive vanishing of \Ext_R^i(M,N) needed to ensure that \Ext_R^i(M,N)=0 for all i0i\gg 0. Our results recover and improve on most of the known bounds in the literature, especially when RR has dimension at most two

    Semi-supervised Convolutional Neural Networks for Flood Mapping using Multi-modal Remote Sensing Data

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    When floods hit populated areas, quick detection of flooded areas is crucial for initial response by local government, residents, and volunteers. Space-borne polarimetric synthetic aperture radar (PolSAR) is an authoritative data sources for flood mapping since it can be acquired immediately after a disaster even at night time or cloudy weather. Conventionally, a lot of domain-specific heuristic knowledge has been applied for PolSAR flood mapping, but their performance still suffers from confusing pixels caused by irregular reflections of radar waves. Optical images are another data source that can be used to detect flooded areas due to their high spectral correlation with the open water surface. However, they are often affected by day, night, or severe weather conditions (i.e., cloud). This paper presents a convolution neural network (CNN) based multimodal approach utilizing the advantages of both PolSAR and optical images for flood mapping. First, reference training data is retrieved from optical images by manual annotation. Since clouds may appear in the optical image, only areas with a clear view of flooded or non-flooded are annotated. Then, a semisupervised polarimetric-features-aided CNN is utilized for flood mapping using PolSAR data. The proposed model not only can handle the issue of learning with incomplete ground truth but also can leverage a large portion of unlabelled pixels for learning. Moreover, our model takes the advantages of expert knowledge on scattering interpretation to incorporate polarimetric-features as the input. Experiments results are given for the flood event that occurred in Sendai, Japan, on 12th March 2011. The experiments show that our framework can map flooded area with high accuracy (F1 = 96:12) and outperform conventional flood mapping methods
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