Second moment of the Husimi distribution as a measure of complexity of quantum states

We propose the second moment of the Husimi distribution as a measure of complexity of quantum states. The inverse of this quantity represents the effective volume in phase space occupied by the Husimi distribution, and has a good correspondence with chaoticity of classical system. Its properties are similar to the classical entropy proposed by Wehrl, but it is much easier to calculate numerically. We calculate this quantity in the quartic oscillator model, and show that it works well as a measure of chaoticity of quantum states.Comment: 25 pages, 10 figures. to appear in PR

Scaling Analysis of Fluctuating Strength Function

We propose a new method to analyze fluctuations in the strength function phenomena in highly excited nuclei. Extending the method of multifractal analysis to the cases where the strength fluctuations do not obey power scaling laws, we introduce a new measure of fluctuation, called the local scaling dimension, which characterizes scaling behavior of the strength fluctuation as a function of energy bin width subdividing the strength function. We discuss properties of the new measure by applying it to a model system which simulates the doorway damping mechanism of giant resonances. It is found that the local scaling dimension characterizes well fluctuations and their energy scales of fine structures in the strength function associated with the damped collective motions.Comment: 22 pages with 9 figures; submitted to Phys. Rev.

Optics Flexibility in the LHC at Top Energy

Flexibility of the LHC optics at top energy has been studied, in terms of betatron tune tunability, mainly for the high-beta optics that requires tunability of the order of half a unit. It has been shown that the tunability at top energy is good enough for the high-beta optics. The results obtained in this study could be useful for other optics and operation modes

Development of a novel integrated model GOTRESS+ for predictions and assessment of JT-60SA operation scenarios including the pedestal

A novel integrated model GOTRESS+ has been developed, which consists of the iterative transport solver GOTRESS as a kernel of the integrated model, the equilibrium and current profile alignment code ACCOME and the neutral beam heating/current-drive code OFMC. GOTRESS is able to robustly find out an exact solution of the stationary-state transport equations even with a stiff turbulent transport model, taking advantage of global optimization techniques such as a genetic algorithm. GOTRESS+ is then suitable for self-consistently assessing the stationary-state plasma performance of JT-60SA as well as ITER and DEMO or validating their feasibility. Recently GOTRESS+ has been extended to incorporate the in-house EPED1 model exploiting the MHD stability code MARG2D and is now able to predict the plasma profiles even with the pedestal over the entire region from the magnetic axis to the plasma boundary in a self-consistent manner. The two JT-60SA operation scenarios including the ITER-like inductive scenario and the high β fully non-inductively current driven scenario have been assessed by GOTRESS+ with the CDBM turbulent transport model and then were found to be feasible with most of the target dimensionless parameters met

A novel Rac1-GSPT1 signaling pathway controls astrogliosis following central nervous system injury

Astrogliosis (i.e. glial scar), which is comprised primarily of proliferated astrocytes at the lesion site and migrated astrocytes from neighboring regions, is one of the key reactions in determining outcomes after CNS injury. In an effort to identify potential molecules/pathways that regulate astrogliosis, we sought to determine whether Rac/Rac-mediated signaling in astrocytes represents a novel candidate for therapeutic intervention following CNS injury. For these studies, we generated mice with Rac1 deletion under the control of the GFAP (glial fibrillary acidic protein) promoter (GFAP-Cre;Rac1(flox/flox)). GFAP-Cre;Rac1(flox/flox) (Rac1-KO) mice exhibited better recovery after spinal cord injury and exhibited reduced astrogliosis at the lesion site relative to control. Reduced astrogliosis was also observed in Rac1-KO mice following microbeam irradiation-induced injury. Moreover, knockdown (KD) or KO of Rac1 in astrocytes (LN229 cells, primary astrocytes, or primary astrocytes from Rac1-KO mice) led to delayed cell cycle progression and reduced cell migration. Rac1-KD or Rac1-KO astrocytes additionally had decreased levels of GSPT1 (G(1) to S phase transition 1) expression and reduced responses of IL-1β and GSPT1 to LPS treatment, indicating that IL-1β and GSPT1 are downstream molecules of Rac1 associated with inflammatory condition. Furthermore, GSPT1-KD astrocytes had cell cycle delay, with no effect on cell migration. The cell cycle delay induced by Rac1-KD was rescued by overexpression of GSPT1. Based on these results, we propose that Rac1-GSPT1 represents a novel signaling axis in astrocytes that accelerates proliferation in response to inflammation, which is one important factor in the development of astrogliosis/glial scar following CNS injury

Fine structure of the isoscalar giant quadrupole resonance in 40Ca due to Landau damping?

The fragmentation of the Isoscalar Giant Quadrupole Resonance (ISGQR) in 40Ca has been investigated in high energy-resolution experiments using proton inelastic scattering at E_p = 200 MeV. Fine structure is observed in the region of the ISGQR and its characteristic energy scales are extracted from the experimental data by means of a wavelet analysis. The experimental scales are well described by Random Phase Approximation (RPA) and second-RPA calculations with an effective interaction derived from a realistic nucleon-nucleon interaction by the Unitary Correlation Operator Method (UCOM). In these results characteristic scales are already present at the mean-field level pointing to their origination in Landau damping, in contrast to the findings in heavier nuclei and also to SRPA calculations for 40Ca based on phenomenological effective interactions, where fine structure is explained by the coupling to two-particle two-hole (2p-2h) states.Comment: Phys. Lett. B, in pres

Non-ideal Ballooning Mode Instability with Real Electron Inertia

Impacts of electron inertia with an electron skin depth (ESD) longer than the realistic value used in early numerical studies on non-ideal ballooning modes (NIBMs) are numerically investigated by a linearized 3-field reduced MHD model. In this paper, 4 different ESDs,are used for an resistivity dependence study of the growth rate of NIBMs, where de s the real ESD and d*e = 10 corresponds to an order of ESD used in a numerical study on collisionless ballooning mode (CBM) reported in [Kleva and Guzdar Phys. Plasmas 6, 116 (1999)]. In the case with the real ESD d*e = de, a transition from resistive ballooning mode (RBM) to CBM occurs in the edge relevant resistivity regime, while the electron inertia effect is overestimated and the growth rate is almost independent of resistivity in the cases with d∗e =√10de and 10de. These results indicate that the real ESD is one of key factors for the edge stability and turbulence analysis

Ozone decomposition in four types of spouted beds, with or without a draft-tube

ArticleJOURNAL OF CHEMICAL ENGINEERING OF JAPAN. 40(9): 761-764 (2007)journal articl