Phase diagram of the pp-spin-interacting spin glass with ferromagnetic bias and a transverse field in the infinite-pp limit

The phase diagram of the $p$-spin-interacting spin glass model in a transverse field is investigated in the limit $p \to \infty$ under the presence of ferromagnetic bias. Using the replica method and the static approximation, we show that the phase diagram consists of four phases: Quantum paramagnetic, classical paramagnetic, ferromagnetic, and spin-glass phases. We also show that the static approximation is valid in the ferromagnetic phase in the limit $p \to \infty$ by using the large-$p$ expansion. Since the same approximation is already known to be valid in other phases, we conclude that the obtained phase diagram is exact.Comment: 16 pages, 4 figures. another additional author, some amendment

Quantum spin coverings and statistics

SL_q(2) at odd roots of unity q^l =1 is studied as a quantum cover of the complex rotation group SO(3,C), in terms of the associated Hopf algebras of (quantum) polynomial functions. We work out the irreducible corepresentations, the decomposition of their tensor products and a coquasitriangular structure, with the associated braiding (or statistics). As an example, the case l=3 is discussed in detail.Comment: 15 page

Clinical, angiographic and procedural correlates of quantitative coronary dimensions after directional coronary atherectomy

AbstractTo define the clinical, angiographic and procedural correlates of quantitative coronary dimensions after directional coronary atherectomy, 400 lesions in 378 patients were analyzed with use of qualitative morphologic and quantitative angiographic methods. Successful atherectomy, defined by a <75% residual area stenosis, tissue retrieval and the absence of in-hospital ischemic complications, was performed in 351 lesions (87.7%). After atherectomy, minimal cross-sectional area increased from 1.2 ± 1.1 to 6.6 ± 4.4 mm2(p < 0.001) and percent area stenosis was reduced from 87 ± 10% to 31 ± 42% (p < 0.001).By univariate analysis, device size (p < 0.001) and left circumflex artery lesion location (p = 0.004) were associated with a larger final minimal cross-sectional area. Conversely, restenotic lesion (p = 0.002), lesion length ≥ 10 mm (p = 0.018) and lesion calcification (p = 0.035) were quantitatively associated with a smaller final minimum cross-sectional area. With use of stepwise multivariate analysis to control for the reference area, atherectomy device size (p = 0.003) and left circumflex lesion location (p = 0.007) were independently associated with a larger final minimal cross-sectional area, whereas restenotic lesion (p = 0.010), diffuse proximal disease (p = 0.033), lesion length ≥ 10 mm (p = 0.026) and lesion calcification (p = 0.081) were significantly correlated with a smaller final minimal cross-sectional area. The number of specimens excised, the number of atherectomy passes and atherectomy balloon inflation pressure did not correlate with the final minimal cross-sectional area.Thus, directional atherectomy results in marked improvement of coronary lumen dimensions, at least in part correlated with the presence of certain clinical, angiographic and procedural factors at the time of atherectomy

Multifragmentation process for different mass asymmetry in the entrance channel around the Fermi energy

The influence of the entrance channel asymmetry upon the fragmentation process is addressed by studying heavy-ion induced reactions around the Fermi energy. The data have been recorded with the INDRA 4pi array. An event selection method called the Principal Component Analysis is presented and discussed. It is applied for the selection of central events and furthermore to multifragmentation of single source events. The selected subsets of data are compared to the Statistical Multifragmentation Model (SMM) to check the equilibrium hypothesis and get the source characteristics. Experimental comparisons show the evidence of a decoupling between thermal and compresional (radial flow) degrees of freedom in such nuclear systems.Comment: 28 pages, 15 figures, article sumitted to Nuclear Physics

Cherenkov Telescope Array Data Management

Very High Energy gamma-ray astronomy with the Cherenkov Telescope Array (CTA) is evolving towards the model of a public observatory. Handling, processing and archiving the large amount of data generated by the CTA instruments and delivering scientific products are some of the challenges in designing the CTA Data Management. The participation of scientists from within CTA Consortium and from the greater worldwide scientific community necessitates a sophisticated scientific analysis system capable of providing unified and efficient user access to data, software and computing resources. Data Management is designed to respond to three main issues: (i) the treatment and flow of data from remote telescopes; (ii) "big-data" archiving and processing; (iii) and open data access. In this communication the overall technical design of the CTA Data Management, current major developments and prototypes are presented.Comment: 8 pages, 2 figures, In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherlands. All CTA contributions at arXiv:1508.0589

Quantum TAP equations

We derive Thouless-Anderson-Palmer (TAP) equations for quantum disordered systems. We apply them to the study of the paramagnetic and glassy phases in the quantum version of the spherical p spin-glass model. We generalize several useful quantities (complexity, threshold level, etc.) and various ideas (configurational entropy crisis, etc), that have been developed within the classical TAP approach, to quantum systems. The analysis of the quantum TAP equations allows us to show that the phase diagram (temperature-quantum parameter) of the p spin-glass model should be generic. In particular, we argue that a crossover from a second order thermodynamic transition close to the classical critical point to a first order thermodynamic transition close to the quantum critical point is to be expected in a large class of systems.Comment: 29 pages, 4 fi

APHRODITE: Design and Preliminary Tests of an Autonomous and Reusable Photo-sensing Device for Immunological Test aboard the International Space Station

Preliminary results of the design and manufacturing of APHRODITE, a compact and versatile device for carrying out analyses of biological fluids during space missions that will be used as a technological demonstrator on board the International Space Station (ISS) for the quantitative determination of salivary biomarkers indicators of alterations of functionality of the immune system. The paper addresses the design of the main subsystems of the analytical device and the preliminary results obtained during the first implementations of the device subsystems and testing measurements. In particular, the system design and the experiment data output of the lab-on-chip photosensors and of the front-end readout electronics are reported in detail

Dissipative effects on quantum glassy systems

We discuss the behavior of a quantum glassy system coupled to a bath of quantum oscillators. We show that the system localizes in the absence of interactions when coupled to a subOhmic bath. When interactions are switched on localization disappears and the system undergoes a phase transition towards a glassy phase. We show that the position of the critical line separating the disordered and the ordered phases strongly depends on the coupling to the bath. For a given type of bath, the ordered glassy phase is favored by a stronger coupling. Ohmic, subOhmic and superOhmic baths lead to different transition lines. We draw our conclusions from the analysis of the partition function using the replicated imaginary-time formalism and from the study of the real-time dynamics of the coupled system using the Schwinger-Keldysh closed time-path formalism.Comment: 39 pages, 13 figures, RevTe

Real-time non-equilibrium dynamics of quantum glassy systems

We develop a systematic analytic approach to aging effects in quantum disordered systems in contact with an environment. Within the closed-time path-integral formalism we include dissipation by coupling the system to a set of independent harmonic oscillators that mimic a quantum thermal bath. After integrating over the bath variables and averaging over disorder we obtain an effective action that determines the real-time dynamics of the system. The classical limit yields the Martin-Siggia-Rose generating functional associated to a colored noise. We apply this general formalism to a prototype model related to the $p$ spin-glass. We show that the model has a dynamic phase transition separating the paramagnetic from the spin-glass phase and that quantum fluctuations depress the transition temperature until a quantum critical point is reached. We show that the dynamics in the paramagnetic phase is stationary but presents an interesting crossover from a region controlled by the classical critical point to another one controlled by the quantum critical point. The most characteristic property of the dynamics in a glassy phase, namely aging, survives the quantum fluctuations. In the sub-critical region the quantum fluctuation-dissipation theorem is modified in a way that is consistent with the notion of effective temperatures introduced for the classical case. We discuss these results in connection with recent experiments in dipolar quantum spin-glasses and the relevance of the effective temperatures with respect to the understanding of the low temperature dynamics.Comment: 56 pages, Revtex, 17 figures include