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The window for preferred axion models

A major goal of axion searches is to reach inside the parameter space region of realistic axion models. Currently, the boundaries of this region depend on somewhat arbitrary criteria, and it would be desirable to specify them in terms of precise phenomenological requirements. I will start with a brief description of the strong CP problem, of the Peccei-Quinn solution predicting the existence of the axion, and of axions as cold Dark Matter. I will then consider the hadronic axion models which involve new heavy quarks Q. By requiring that i) the Q are sufficiently short lived to avoid issues with long lived strongly interacting relics, ii) no Landau poles are induced below the Planck scale, fifteen cases are selected, which define a phenomenologically preferred axion window.

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Low secondary emission surfaces for multipactor suppression in space

Multipactor is an undesirable effect produced when high power RF electric fields are used in vacuum. In space, this effect is very important since affects the wave-guides for communications limiting the power of the transmissions. Any electron present near the electric field is accelerated impinging the wave-guide walls and producing more electrons by secondary emission which are also accelerated. The final result is an electron cloud which can even destroy the wave-guide. In this talk I will first present the main characteristics of the multipactor effect in space, its relation with secondary emission and how this effect could be mitigated. Then I will present a brief summary of the late anti-multipactor coatings developed in our laboratory during the last years in cooperation with the ESA. Since the problem is still far away from being solved, I will present new ideas for antimultipactor coatings to be developed under an European ERA.Net Project.

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Signatures from simple scalar WIMP candidates

Scalar WIMP are somewhat less popular than their fermionic counterparts. Yet, they have specific and interesting phenomenology and are rather well-motivated, at least from a bottom-up perspective to the dark matter particle problem. In this talk, after a personal perspective on some dark matter model building aspects, I will discuss in details the phenomenology of some very simple scalar WIMP candidates (i.e. the scalar 7-plet minimal dark matter candidate and a real scalar through the so-called vector-like portal), with a focus on their possible indirect detection through searches for gamma-ray spectral features

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High Gradient Acceleration Studies at SLAC

Accelerating gradient is one of the crucial parameters affecting the design, construction, cost, and energy reach of the next generation linear accelerators. The main phenomenon that limits the gradient of rf linacs is vacuum rf breakdown. I present recent R&D efforts directed toward increasing the operating gradients of normal conducting accelerating structures. This work includes study of the basic physics of rf breakdown phenomena and novel methods of building the accelerating structures. The study of the basic physics includes high power tests of short X-band accelerating cavities at room and cryogenic temperatures, and high gradient tests of mm-wave accelerating structures. Novel methods of manufacturing include precision milling of full scale accelerating structures and use of new materials such as hard copper-silver alloy.

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Autumn Institute – Challenges in collider physics

Aim of the workshop: This meeting aims at gathering theorists and experimentalists working in the Rome area in the field of collider physics. In an informal environment, we shall discuss several issues, which are relevant at present (LHC) and future accelerators. In particolar, we shall debate the phenomenology of dark photons, parton distribution functions, the state of the art of higher order QCD corrections as well as top-quark phenomenology, paying special attention to CP violation in top decays. Speakers: Roberto Bonciani (Universita' di Roma `La Sapienza') "Planar two-loop corrections to Higgs+jet production in QCD" Marco Bonvini (Universita' di Roma `La Sapienza') "Theory uncertainty from missing higher orders" Lucio Cerrito (Universita' di Roma `Tor Vergata') "Top B physics with the ATLAS experiment" Marco Guzzi (Manchester University) "The structure of the proton global analysis in QCD and LHC precision physics" Barbara Mele (INFN Roma) "Massless dark-photon phenomenology at colliders"

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The Extreme Energy Events project: a sparse array of telescopes for cosmic radiation

The Extreme Energy Events project is meant to be the most extensive experiment to detect secondary cosmic particles in Italy. To this aim, a network of more than 50 telescopes has been built at CERN and installed in high schools distributed all over the Italian territory. Each EEE telescope comprises three layers of large area (80 x 160 cm2) Multi-gap Resistive Plate Chambers (MRPCs) with six 300 µm gas gaps each, based on the same technology used for the ALICE time-of-flight detector at LHC. The telescopes are capable of reconstructing the trajectories of the charged particles traversing them with a good angular resolution. The excellent performance of the EEE telescopes allows a large variety of studies, ranging from the measure of the local muon flux in a single telescope, to detecting extensive air showers producing time correlations in the same metropolitan area, to searching for large-scale correlations between showers detected in telescopes tens, hundreds or thousands of kilometers apart. Together with its scientific goals, the EEE Project also aims to involve high school students and teachers in the construction, testing and start-up of the EEE telescope in their school, later on in its maintenance and data-acquisition, and finally in the analysis of the data. During the last couple of years the experiment entered its maturity phase, and a great boost has been given to the EEE project by organizing simultaneous and centralized data taking with the whole telescope array contributing. The raw data from all telescopes are transferred to CNAF ...

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Terzo Incontro Nazionale di Fisica Nucleare INFN2016

Il Terzo Incontro Nazionale di Fisica Nucleare si terrà a Frascati presso i Laboratori Nazionali di Frascati dal 14 al 16 novembre 2016. Questa serie di incontri, di cui il primo si è tenuto a Catania presso i Laboratori Nazionali del Sud nel novembre del 2012 e il secondo a Padova e ai Laboratori Nazionali di Legnaro nel marzo del 2014, nasce come iniziativa di ricercatori INFN e universitari con l'obiettivo di creare un'occasione di confronto per la comunità italiana di fisici, teorici e sperimentali, attivi nel campo della fisica nucleare. L’incontro, promosso dalle Commissioni Scientifiche Nazionali 3, 4 e 5, è organizzato in cinque sessioni plenarie nel corso delle quali saranno esaminate e discusse problematiche relative a diversi ambiti della fisica adronica e nucleare: Dinamica dei quark e degli adroni Transizioni di fase e plasma di quark e gluoni Struttura nucleare e dinamica delle reazioni Astrofisica nucleare Applicazioni e interdisciplinarietà della fisica nucleare Le sessioni prevedono relazioni su invito di carattere generale che illustreranno le attività della nostra comunità nei vari settori, inquadrandole nel contesto internazionale, mettendo in evidenza i punti di contatto con altre linee di ricerca e delineandone le prospettive. In questo incontro saranno previste delle presentazioni da parte di giovani ricercatori, selezionati dal Comitato Organizzatore sulla base degli abstracts che verranno ricevuti. È inoltre fissata una sessione di posters per martedi pomeriggio. Verranno premiati  i tre migliori poster e le tre migliori presentazioni dei giovani ricercatori. Affinché tutti i partecipanti abbiano la possibilità di intervenire, alla ...

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