Particle Identification in the ALICE Experiment

The particle identification capabilities of the ALICE experiment are unique among the four major LHC experiments. The working principles and excellent performance of the central barrel detectors in a high-multiplicity environment are presented as well as two physics examples: the extraction of transverse momentum spectra of charged pions, kaons, protons, and the observation of the anti-4He-nucleus.Comment: Quark Matter 2011 Proceeding

Universal strangeness production and size fluctuactions in small and large systems

Strangeness production in high multiplicity events gives indications on the transverse size fluctuactions in nucleus-nucleus ($AA$), proton-nucleus ($pA$) and proton-proton ($pp$) collisions. In particular the behavior of strange particle hadronization in "small" ($pp,pA$) and "large" ($AA$) initial configurations of the collision can be tested for the specific particle species, for different centralities and for large fluctuations of the transverse size in $pA$ and $pp$ by using the recent ALICE data. A universality of strange hadron production emerges by introducing a dynamical variable proportional to the initial parton density in the transverse plane.Comment: talk at EPS-HEP conference , Venice, 201

Fast Long-Distance Control of Spin Qubits by Photon Assisted Cotunneling

We investigate theoretically the long-distance coupling and spin exchange in an array of quantum dot spin qubits in the presence of microwaves. We find that photon assisted cotunneling is boosted at resonances between photon and energies of virtually occupied excited states and show how to make it spin selective. We identify configurations that enable fast switching and spin echo sequences for efficient and non-local manipulation of spin qubits. We devise configurations in which the near-resonantly boosted cotunneling provides non-local coupling which, up to certain limit, does not diminish with distance between the manipulated dots before it decays weakly with inverse distance.Comment: 17 pages (including 8 pages of Appendices), 2 figure

Electric-field dependent g-factor anisotropy in Ge-Si core-shell nanowire quantum dots

We present angle-dependent measurements of the effective g-factor g* in a Ge-Si core-shell nanowire quantum dot. g* is found to be maximum when the magnetic field is pointing perpendicular to both the nanowire and the electric field induced by local gates. Alignment of the magnetic field with the electric field reduces g* significantly. g* is almost completely quenched when the magnetic field is aligned with the nanowire axis. These findings confirm recent calculations, where the obtained anisotropy is attributed to a Rashba-type spin-orbit interaction induced by heavy-hole light-hole mixing. In principle, this facilitates manipulation of spin-orbit qubits by means of a continuous high-frequency electric field

Detailed and large-scale cost/benefit analyses of landslide prevention vs. post-event actions

The main aim of this paper is to test economic benefits of landslide prevention measures vs. post-event emergency actions. To this end, detailed- and large-scale analyses were performed in a training area located in the northeastern Italian pre-Alps that was hit by an exceptional rainfall event occurred in November 2010. On the detailed scale, a landslide reactivated after 2010 event was investigated. Numerical modeling demonstrated that remedial works carried out after the landslide – water-removal intervention such as a drainage trench – could have improved slope stability if applied before its occurrence. Then, a cost/benefit analysis was employed. It defined that prevention would have been economically convenient compared to a non-preventive and passive attitude, allowing a 30 % saving relative to total costs. On the large scale, one of the most affected areas after 2010 event was considered. A susceptibility analysis was performed using a simple probabilistic model, which allowed to highlight the main landslide conditioning factors and the most hazardous and vulnerable sectors. In particular, such low-cost analysis demonstrated that almost 50 % of landslides occurred after 2010 event could be foreseen and allowed to roughly quantify benefits from regional landslide prevention. However, a large-scale approach is insufficient to carry out a quantitative cost/benefit analysis, for which a detailed case-by-case risk assessment is needed. The here proposed approaches could be used as a means of preventive soil protection in not only the investigated case study but also all those hazardous areas where preventive measures are needed

Two- versus three-dimensional connectivity testing of first-order queries to semi-algebraic sets

This paper addresses the question whether one can determine the connectivity of a semi-algebraic set in three dimensions by testing the connectivity of a finite number of two-dimensional ``samples'' of the set, where these samples are defined by first-order queries. The question is answered negatively for two classes of first-order queries: cartesian-product-free, and positive one-pass.Comment: corrected minor confusion in Proof of Theorem

Anisotropic Pauli spin blockade in hole quantum dots

We present measurements on gate-defined double quantum dots in Ge-Si core-shell nanowires, which we tune to a regime with visible shell filling in both dots. We observe a Pauli spin blockade and can assign the measured leakage current at low magnetic fields to spin-flip cotunneling, for which we measure a strong anisotropy related to an anisotropic g-factor. At higher magnetic fields we see signatures for leakage current caused by spin-orbit coupling between (1,1)-singlet and (2,0)-triplet states. Taking into account these anisotropic spin-flip mechanisms, we can choose the magnetic field direction with the longest spin lifetime for improved spin-orbit qubits

Intuitive perception and the competitive advantage of small family businesses: an exploratory study

We assess the closeness of perceptions between managers and customers of two small family-owned businesses ("FBs") and two larger non-FBs in Sardinia, Italy, in exploring how local retail shops may compete against international superstores. While the decline of small, High Street businesses has been widely reported, we present a more nuanced perspective of their competitiveness by suggesting how these typically family-run businesses may hold a competitive advantage over larger non-FBs based on their welldeveloped "perceptive concordance" with customers. Our findings have scholarly and managerial implications in the way that both FBs and non-FBs may gain competitive advantage by securing their customers' continuing support