Tag Archives: Evento scientifico

Aim of the workshop: In spite of its consolidated experimental success, the Standard Model of particle physics falls short of describing all observed phenomena. Elegant and well motivated theoretical ideas, such as Supersymmetry, Technicolor or Grand Unification, have so far found no support from experimental results. The longed-for discovery of some kind of physics beyond the Standard Model, that could guide us to replace these ideas with new theoretical paradigms, has so far escaped all experimental efforts. Given this situation, any serious attempt to approach the incompleteness of the Standard Model from originally different and unconventional perspectives should receive proper consideration. Fearless exploration outside the box might provide more insights than lengthy struggles through standard thinking. During this 3-day workshop we plan to review some recent attempts to approach fundamental physics issues from non standard perspectives. We plan to have only two or three talks each day and plenty of time to analyze jointly the good and bad of the various proposals, confront ideas and discuss. Scientific Program and Speakers: John Donoghue (Massachusetts U., Amherst) “Quantum Field Theory for Gravity” Gia Dvali  (LMU, ASC & MPI, Munich & NYU, CCPP, New York)  “Classicalization” Renate Loll (Radboud U., NL) “Quantum Gravity, or: Give me (more) observables!”  Matthew McCullough  (CERN) “Hyperbolic Higgs, Clockwork and Relaxion” Holger F.B. Nielsen (Bohr Inst.) “Dark Matter, Double Supernova Neutrino Explosion, Degenerate Vacua, Predetermination? Why the SM Group?” Roberto Percacci  (SISSA)    “Asymptotic Safety” Eugenio Bianchi  (Penn State) “Entanglement in Loop Quantum Gravity”  Michael Spannowsky  (Durham U. & Durham U., IPPP) “Higgsplosion, Higgspersion …

Modern developments in hadron physics emphasize the role of parton intrinsic motion and spin, and their correlations, which are crucial to our full understanding of the nucleon structure in terms of the quark and gluon degrees of freedom in QCD. The main aim of the workshop is to provide an environment in which present theoretical and experimental knowledge in the field of transversity, transverse-momentum dependent distribution and fragmentation functions as well as generalized parton distribution functions will be presented and discussed in depth, together with new theoretical ideas and experimental perspectives. The scientific program will consist of presentations (by invitation only), featuring review talks (30 minutes + 10 minutes for discussion) and research talks (20 minutes + 5 minutes or 15 minutes + 5 minutes for discussion). In addition a round-table will be devoted to the perspectives of the field. The Workshop follows the successful editions held in : 2005 on Lake Como (Italy), 2008 Ferrara (Italy), 2011 in Losinj (Croatia), 2014 Cagliari (Italy).

FAMU will realize the first measurement of the hyperfine splitting (hfs) in the 1S state of muonic hydrogen ΔEhfs(μ-p)1S – providing crucial information on proton structure and muon-nucleon interaction – by using an intense pulsed muon beam, and an on-purpose developed high-energy mid infrared tunable laser. FAMU initiates a new class of experiments representing a significant leap forward in the quality of spectroscopic measurements in muonic atoms; specifically, it will provide the proton Zemach radius rZ with higher precision than previously possible, disentangling discordant theoretical values and will quantify any level of discrepancy that may exist between values of rZ as extracted from normal and muonic hydrogen atoms. It will set a needed cornerstone result about not yet explained anomalies within the proton charge rch radius. The Zemach radius rZ and the r.m.s charge radius rch are the only proton shape-related values that can be directly extracted from experimental data, and rZ is the only one that carries information about the proton’s magnetic dipole moment distribution. A pulsed intense muon beam entering the MUST hydrogen gas target will form muonic hydrogen atoms. FAMU’s theoretical and experimental effort will establish new limits on the proton structure parameters measuring the muonic hydrogen transition ΔEhfs(μ-p)1S with unprecedented precision – δλ/λ < 10-5 – and will shed light on the low momentum limit of the magnetic-to-charge form factor ratio.

In cold regions of the Interstellar Medium (ISM), like star-forming regions or protoplanetary disks, molecules form or accrete on the surface of micron-sized dust particles. The resulting icy mantles represent the main reservoir of molecular material (beside H2). In these regions, thermal desorption can be neglected, but energetic processes, for instance induced by cosmic rays or photon impact on the ices, can promote their desorption into gas phase. Providing experimental constraints on these processes is important for astrophysical modelling and for explaining the presence of organic compounds in UV-X irradiated regions. Desorption of neutral particles and ions is also crucial for the vacuum performance of cryogenic parts present in accelerators, such as the superconducting magnets of the Large Hadron Collider (LHC) at CERN or in use at synchrotron radiation facilities, which depends critically on the photodesorption of molecular gases by synchrotron emission originating from the relativistic particles. We have developed an experimental approach for the study of the photodesorption from thin molecular films at low temperatures (10-15 K), using the brilliance and the tunability of synchrotron radiation at the SOLEIL facility in order to get absolute desorption yields in the UV energy range (DESIRS beamline) and more recently in the soft X-ray energy range (SEXTANTS beamline). The main results obtained from the irradiation of pure and mixed-ices of weakly bound species will be reviewed. Emphasis will be put an efficient desorption induced by the electronic relaxation of the first electronic excited state of CO in the 8-10 eV range and …

A better knowledge of the nuclear cross sections is becoming essential for the Hadrontherapy improvement and for the astronauts radio-protection. For this purpose the experiment FOOT ( FragmentatiOn Of Target ) has been envisaged. The direct and inverse kinematic approach will be used to measure the cross sections respectively after the Bragg peak and in the proton entrance channel. For this purpose a key element in FOOT is the magnetic spectrometer based on the monolithic active pixel sensor. The pixel tracker is composed by three main elements: the Vertex detector, the bending permanent magnet and a larger acceptance two layer inner tracker. Both the four layer Vertex and the downstream tracker will use the MIMOSA28 pixel sensors developed by the Strasbourg PICSEL group. An overview of the detector with its main simulated characteristics will be described and some details on main implementation problems will also be underlined.

Pixel sensors built directly from the CMOS integrated circuit technology, as known as CPS or MAPS, are gaining more and more enthusiasts for vertexing and tracking in subatomic physics. Indeed CMOS pixel sensors feature genuinely spatial resolution in the micrometers range and material budget well below 1% of radiation length, which are key assets for these applications. It was less straightforward, and took some developments, to bring MAPS in the realm of nanosecond range time resolution or microsecond integration time, and radiation tolerance matching 10^15 neutron (1 Mev equivalent) per cm2. These last achievements required the depletion of the sensitive volume, which in turn yield an interesting byproduct in term of energy resolution. For instance, 6 keV X-rays can be reconstructed with about 300 eV resolution, roughly just a factor 3 from the absolute Fano limit. Such a performance opens up perspectives for spectroscopy in a broad range of applications, well beyond high energy physics. A less well recognised but nonetheless very strong point of MAPS is their ability to be easily integrated in a system. This stems from two main reasons: these sensors rely on an industrial technology widely used on the consumer market and they can reach extremely low power dissipation, since there is not much amplification required. This seminar intends to introduce briefly the basic operational concept of CMOS pixel sensors and then to cover the latest developments pushing performances (energy, timing, smartness) to their current limits. These discussions will embark us on a journey through the …

A possible application of DAFNE after the end of the Siddharta RUN is using the positron ring as Linac pulse stretcher to produce a high duty=factor beam. The PADME experiment, dedicated to the search for the dark photon (A’), is going to use the BTF beam with 200 ns pulse length and 49 Hz repetition rate, corresponding to a duty-factor of 10e-5. The low duty-factor is the major limitation for the PADME experiment at BTF. By injecting the beam in the DAFNE positron ring and by extracting it with a slow resonant extraction on the m/3 resonance, a duty factor (10e-2 = 0.2/20 ms) nearly a factor 1000 larger can be achieved. This extracted beam would be extremely interesting for PADME. In this talk the modifications required for the ring and the transfer line and a lattice satisfying the conditions for the resonant extraction will be presented. A preliminary estimate of the characteristics of the extracted beam extraction and a description of the work still needed to optimize the parameters will be given.

                                                  The aim of the “New frontiers in testing quantum mechanics from underground to the space” workshop is to discuss the possible limits of validity of quantum mechanics, including the theories which go beyond the standard quantum mechanics, as well as experiments aiming to test them. The role which gravity may play in this context will be discussed, together with future strategies. Testing quantum mechanics in experiments performed in underground laboratories, in earth-based laboratories and in space, in order to make a decisive step forward towards a deeper understanding of quantum mechanics and of the observational process, if fundamental for a deeper understanding of Nature and Universe and also for the future quantum technologies. The workshop is organized in the framework of the Foundational Questions Institute, FQXi, 2017 mini-grant Spring project: Observers and Observations from Underground to Space, and is sponsored by the Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi, Roma, by INFN and by the John Templeton Foundation (" Hunt for the “impossible atoms” project). Organizers: Angelo Bassi, Univ. and INFN Trieste, Italy Catalina Curceanu, LNF-INFN, Italy (Chair) Johann Marton, SMI-Vienna, Austria Kristian Piscicchia, Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi Roma, and LNF-INFN Frascati (Roma), Italy Alessandro Scordo, LNF-INFN, Italy

Aim of the workshop: The Autumn Institute II will gather theorists and experimentalists, working mostly in the Rome area and at CERN in the field of collider physics. In an informal environment, we shall investigate a few selected topics on possible tests of the Standard Model at low and high energies. In particular, we will discuss open issues in the dark sectors (dark photons and dark matter), the prospects for Lepton Flavour Violation in the Mu2e experiment, tests of discrete symmetries, such as CP and CPT at KLOE, as well as the latest observations of top-pair production in association with Higgs bosons at the LHC. Speakers: Barbara Mele (INFN Roma) "Searching for a massless dark photon" Stefano Miscetti (INFN LNF) "Mu2e: The search for muon-to-electron conversion at Fermilab" Doojin Kim (CERN) "Searches for `Relativistic' Inelastic Dark Matter" Valentina Vecchio (Università di Roma 3) "Evidence for ttH production with the ATLAS detector" Antonio Di Domenico (Università di Roma `La Sapienza') "Test of discrete symmetries with neutral kaons at KLOE-2"

The problem of the theoretical description of the critical temperature Tc of a Fermi superfluid dates back to the work of Gor’kov and Melik-Barkhudarov (GMB), who addressed it for a weakly-coupled (dilute) superfluid in what would today be referred to as the (extreme) BCS (weak-coupling) limit of the BCS-BEC crossover. The point made in this context by GMB was that particle-particle (pairing) excitations, which are responsible for superfluidity to occur below Tc, and particle-hole excitations, which give rise to screening also in a normal system, get e ectively disentangled from each other in the BCS limit, thus yielding a reduction by a factor 2:2 of the value of Tc obtained when neglecting screening e ects. Subsequent work on this topic, that was aimed at extending the original GMB argument away from the BCS limit, has tout court kept this disentangling between pairing and screening throughout the BCS-BEC crossover, without realising that the conditions for it to be valid are soon violated away from the BCS limit. Here, we reconsider this problem from a more general perspective and argue that pairing and screening are intrinsically entangled with each other along the whole BCS-BEC crossover but for the BCS limit considered by GMB, with the particle-hole excitations soon transmuting into particle-particle excitations away from this limit. We substantiate our argument by performing a detailed numerical calculation of the GMB diagrammatic contribution suitably extended to the whole BCS-BEC crossover, where the full wave-vector and frequency dependence occurring in the repeated two-particle in medium …