The Higgs sector of the minimal <Emphasis Type="Italic">B</Emphasis>−<Emphasis Type="Italic">L</Emphasis> model at future Linear Colliders

We investigate the phenomenology of the Higgs sector of the minimal B−L extension of the Standard Model at a future e ⁺ e ⁻ Linear Collider. We consider the discovery potential of both a sub-TeV and a multi-TeV machine. We show that, within such a theoretical scenario, several novel production and decay channels involving the two physical Higgs states, precluded at the LHC, could experimentally be accessed at such machines. Amongst these, several Higgs signatures have very distinctive features with respect to those of other models with enlarged Higgs sector, as they involve interactions of Higgs bosons between themselves, with Z′ bosons as well as with heavy neutrinos. In particular, we present the scope of the Z′ strahlung process for single and double Higgs production, the only suitable mechanism enabling one to access an almost decoupled heavy scalar state (therefore outside the LHC range).     

<Emphasis Type="Italic">Z</Emphasis>′ discovery potential at the LHC in the minimal <Emphasis Type="Italic">B</Emphasis>–<Emphasis Type="Italic">L</Emphasis> extension of the standard model

We present the Large Hadron Collider (LHC) discovery potential in the Z′ sector of a \(U(1)_{B\mbox{--}L}\) enlarged Standard Model (that also includes three heavy Majorana neutrinos and an additional Higgs boson) for \(\sqrt{s}=7\), 10 and 14 TeV centre-of-mass (CM) energies, considering both the \(Z'_{B\mbox{--}L}\rightarrow e^{+}e^{-}\) and \(Z'_{B\mbox{--}L}\rightarrow\mu^{+}\mu^{-}\) decay channels. The comparison of the (irreducible) backgrounds with the expected backgrounds for the DØ experiment at the Tevatron validates our simulation. We propose an alternative analysis that has the potential to improve the DØ sensitivity. Electrons provide a higher sensitivity to smaller couplings at small \(Z'_{B\mbox{--}L}\) boson masses than do muons. The resolutions achievable may allow the \(Z'_{B\mbox{--}L}\) boson width to be measured at smaller masses in the case of electrons in the final state. The run of the LHC at \(\sqrt{s}=7\) TeV, assuming at most \(\int\mathcal{L} \sim1\) fb^?1, will be able to give similar results to those that will be available soon at the Tevatron in the lower mass region, and to extend them for a heavier M _Z′.     

Preliminary study on different technological tools and polymeric materials towards superhydrophobic surfaces for automotive applications

Nature-inspired fabrication of micro-structured superhydrophobic plastic film was aimed in this work in order to achieve smart materials with self-cleaning properties. Replicas of silicon masters were fabricated from different mixtures of base elements and by different processes. Corresponding microstructures were investigated by contact angle measurements, scanning electron microscopy and spectrophotometric analysis. Independently of the technology employed, the obtained films exhibited high contact angle value (larger than 150°), but while the acrylic polymers presented strong demoulding drawbacks, the polydimethylsiloxane (PDMS) films had good properties in terms of both contact angle and optical transparency. The results showed that most of the patterns realized by replica moulding and hot-embossing (on PDMS and polypropylene (PP), respectively) produced superhydrophobic self-cleaning surfaces.     

Effect of grain-size on the ethanol vapor sensing properties of room-temperature sputtered ZnO thin films

We have investigated the gas sensing properties of ZnO thin films (100 to 200 nm thickness) deposited by room-temperature radio frequency magnetron sputtering. The sensitivity of the films to ethanol vapor was measured in the 10 to 50 ppm concentration range at operating temperatures between 200 and 400 °C. A synergetic effect of decreasing grain size and increasing operating temperature was observed towards the improvement of the sensitivity, reaching a value of 54 and a limit of detection as low as 0.61 ppm. The decrease in the grain size resulted in prolonged response time but faster recovery. In any case, both response time and recovery time are < 400 s. The results demonstrate that room-temperature magnetron sputtering is a viable approach to enhance the performances of ZnO films in sensors for ethanol vapor.

Sensor response for ZnO films in presence of 50 ppm ethanol as a function grain size and temperature