Elliptic Flow from Non-equilibrium Initial Condition with a Saturation Scale

A current goal of relativistic heavy ion collisions experiments is the search for a Color Glass Condensate as the limiting state of QCD matter at very high density. In viscous hydrodynamics simulations, a standard Glauber initial condition leads to estimate $4\pi \eta/s \sim 1$, while a Color Glass Condensate modeling leads to at least a factor of 2 larger $\eta/s$. Within a kinetic theory approach based on a relativistic Boltzmann-like transport simulation, we point out that the out-of-equilibrium initial distribution proper of a Color Glass Condensate reduces the efficiency in building-up the elliptic flow. Our main result at RHIC energy is that the available data on $v_2$ are in agreement with a $4\pi \eta/s \sim 1$ also for Color Glass Condensate initial conditions, opening the possibility to describe self-consistently also higher order flow, otherwise significantly underestimated, and to pursue further the search for signatures of the Color Glass Condensate.Comment: 6 pages, 4 figures. // Title changed, some discussion added, main conclusions unchanged. Version accepted for publication on Phys. Lett.

Italy

Il volume \ue8 uno studio comparativo degli ordinamenti giuridici dei 27 Stati membri dell'Unione europea. Il contributo di cui il sottoscritto risulta co-autore insieme a Ruggieri F. espone in inglese, in un formato comune, i tratti essenziali della procedura penale italiana

Porting Decision Tree Algorithms to Multicore using FastFlow

The whole computer hardware industry embraced multicores. For these machines, the extreme optimisation of sequential algorithms is no longer sufficient to squeeze the real machine power, which can be only exploited via thread-level parallelism. Decision tree algorithms exhibit natural concurrency that makes them suitable to be parallelised. This paper presents an approach for easy-yet-efficient porting of an implementation of the C4.5 algorithm on multicores. The parallel porting requires minimal changes to the original sequential code, and it is able to exploit up to 7X speedup on an Intel dual-quad core machine.Comment: 18 pages + cove

On the ground state of gapless two flavor color superconductors

This paper is devoted to the study of some aspects of the instability of two flavor color superconductive quark matter. We find that, beside color condensates, the Goldstone boson related to the breaking of $U(1)_A$ suffers of a velocity instability. We relate this wrong sign problem, which implies the existence of a Goldstone current in the ground state or of gluonic condensation, to the negative squared Meissner mass of the $8^{th}$ gluon in the g2SC phase. Moreover we investigate the Meissner masses of the gluons and the squared velocity of the Goldstone in the multiple plane wave LOFF states, arguing that in such phases both the chromo-magnetic instability and the velocity instability are most probably removed. We also do not expect Higgs instability in such multiple plane wave LOFF. The true vacuum of gapless two flavor superconductors is thus expected to be a multiple plane wave LOFF state.Comment: 16 pages, RevTe3X4 styl

GREEN LOANS EXPERIENCES AS INVESTMENT MULTIPLIER SCHEMES

In recent years Italian national and regional governments have been active in promoting energy efficiency and renewable energies. The most effective measures are focused on the residential sector: feed-in tariffs for photovoltaic systems (higher tariffs for building integrated small plants), 55% tax credits for energy efficiency investments (windows or boilers substitutions, walls and roof insulations or even complete building refurbishments). Recent surveys show that in some cases the customers are informed but cannot afford to pay for the needed investments and they prefer not to ask for loans, paying interests. In this situation the final customer may decide to opt for low quality refurbishments, not necessarily affecting the building energy consumption. For these reasons there can still be some room left for some local supporting initiatives. In the Province of Milan the Mutuo A-profitto provided green loans with no interest to the consumers to all those who want to perform an energy efficient refurbishment of their house: local banks provided the third party financing interest were paid half by the bank itself and half by the province administration the project designer or the installer had to declare the expected energy savings In this way the customer obtained an interest-free loan up to 7 years: since the amount of the instalment could not exceed the amount of the expected economic savings, even the annual cash flow will be positive. Eligible measures include: glaze substitutions, walls and roof insulation, heating systems, solar water heater, heat pumps. Since 2007, the Milanese Province administration has provided 1,35 million Euro funding, which mobilized 16\ua0million Euro of total investments. The Piedmont Region has recently introduced a similar scheme addressed to households and companies. The paper provides an in depth description of the schemes adopted in Milan, an evaluation of the results and a comparison with the Piedmonts\u2019 experience and the "\ue9co-pr\ueat \ue0 taux z\ue9ro" (zero interest green loans) recently introduced in France by the Minist\ue8re du D\ue9veloppement Durable