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Rencontres de Moriond EW 2013

→ Europe/Paris
Jean Marie Frere (ULB Brussels), Lydia Iconomidou-Fayard (LAL)
Description

The XLVIIIth Rencontres de Moriond session devoted to ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES will be held in La Thuile from Saturday March 2rd to Saturday March 9th, 2013.

La Thuile is a pleasant winter sport resort located in the Italian Alps, at 1450 m alt., about 120 km from Geneva. The nearest international airport is Geneva (Switzerland).

Since its foundation in 1966 by Jean Tran Thanh Van, the Rencontres de Moriond bring together theorists and experimentalists for in-depth discussions on recent findings and new ideas in elementary particle physics in a pleasant, relaxed and intimate atmosphere.

The meeting is intended to promote fruitful collaboration between experimentalists and theorists and between various institutions by bringing together a limited number of physicists and astrophysicists in beautiful and inspiring surroundings.

This session is devoted to electroweak interactions and to unified theories.
The Rencontres de Moriond are sponsored by

Program
Support
  • dim. 3 mars
    • Heavy Flavours

      Sunday March 3rd: Heavy Flavours + QCD input

      • 1
        The GIM Mechanism: origin, predictions and recent uses
        The GIM Mechanism was introduced by Sheldon L. Glashow, John Iliopoulos and Luciano Maiani in 1970, to explain the suppression of Delta S=1, 2 neutral current processes and is an important element of the unified theories of the weak and electromagnetic interactions. Origin, predictions and uses of the GIM Mechanism are illustrated. Flavor changing neutral current processes (FCNC) represent today an important benchmark for the Standard Theory and give strong limitations to theories that go beyond ST in the few TeV region. Ideas on the ways constraints on FCNC may be imposed are briefly described
        Orateur: Prof. luciano maiani (cern)
        Paper
        Slides
      • 2
        Rare decays and CP/T Violation in Babar
        Orateur: Simon Akar (Laboratoire de physique nucléaire et des hautes energies)
        Slides
      • 3
        New results from Belle
        Orateur: Matthias Huschle (Institut fuer Experimentelle Kernphysik, Karlsruher Institut fuer Technologie)
        Slides
      • 4
        Charm mixing and CP Violation in LHCb
        Orateur: Thomas Hampson (University of Bristol)
        Paper
        Slides
      • 10:05
        Tea or Coffee break
      • 5
        CP violation in Charm Physics
        Orateur: Dr Paride Paradisi (CERN)
      • 6
        SU(3) flavour and CP violation in charm decays
        We analyze decays of charm mesons to two pseudoscalars, D->PP, in an flavour-SU(3) framework, including first order symmetry breaking. We perform fits to the full up-to-date (pre-Moriond) data set with octet mesons, including for the first time all SU(3)-breaking amplitudes in the CKM-leading part. This allows for making general statements on the requisite size of SU(3) breaking and enhancements for the penguin contributions to describe the data. We furthermore show how future data can help distinguishing between different new physics models and the standard model.
        Orateur: Dr Martin Jung (TU Dortmund)
      • 7
        CP Violation in the Bs system in LHCb
        Orateur: Sean Benson (University of Edinburgh)
        Paper
        Transparents
    • Heavy Flavours

      Sunday March 3rd: Heavy Flavours + QCD input

      • 8
        Hadronic b decays to open charm in LHCb
        Orateur: Dr Vladimir Gligorov (CERN)
        Paper
        Slides
      • 9
        Latest results on Bs->μμ and other rare decays in LHCb
        Rare heavy flavour decays occurring through flavour-changing neutral-current processes are an ideal place to search for the effects of potential new particles that modify the decay rates. The LHCb experiment, a dedicated heavy flavour experiment at the LHC, has recorded the world's largest sample of heavy meson decays. The status of the rare decay analyses with this sample is reviewed. The first evidence for the very rare decay B^0_s to µ+µ- is presented together with the most stringent upper exclusion limits on the branching fraction of decays of B^0 and K^0_s mesons into two muons. The first limit ever set on the B to 4µ decays is also presented.
        Orateur: Dr Alessio Sarti (Universita' di Roma "La Sapienza")
        Paper
        Slides
      • 10
        B -> K(*)+2 leptons @ Low Recoil and Physics Implications
        This talk will cover the recent achievements in theory to describe the semileptonic rare |Delta B|=1 exclusive decays in the kinematic region of low hadronic recoil. The region is accessible to the current and future experimental searches, and has benefits in probing the Standard Model as well as the requisite hadronic form factors. Ratios of the latter can already be extracted from present data, and are compared to theoretical determinations by non-perturbative means, such as lattice QCD and QCD sum rules.
        Orateur: Gudrun Hiller (Dortmund)
        Slides
      • 11
        The New Frontier in b->s penguin decays
        I will discuss the recent developments in the phenomenology of the decay B->K*ll. Its angular distribution leads to a set of theoretically clean observables. Current analyses by the LHCb collaboration are focusing on these observables, and will lead to very precise measurements due to the large statistics collected. Besides being theoretically clean, these observables are very sensitive to physics beyond the SM. I will show that, within a time frame of one year, the B->K*ll decay will either 1) reveal NP, or 2) set the strongest constraints up to date on NP in magnetic and semileptonic b->s operators.
        Orateur: Dr Javier Virto (IFAE / U. Autonoma de Barcelona)
        Paper
        Transparents
      • 18:20
        Tea or Coffee break
      • 12
        Heavy flavour in TeVatron
        Orateur: Sandro De Cecco (University of Paris VI and VII - LPNHE)
        Paper
        Slides
      • 13
        Heavy Flavor Measurements at LHC
        ATLAS and CMS measurements in the area of heavy flavor physics are reviewed with focus on the most recent results. The topics discussed include heavy flavor production rates and properties, exclusive b-hadron production, with attention to the recent observations of rare b-hadrons and to the measurements of Lambda_b production cross section, lifetime and mass. Differential production cross sections and polarization measurements of Upsilon states are presented, along with production ratios of chi_c states in the charmonium system. Evidence for a new Xsi_b state and observations of structures in the J/Psi phi spectrum from B+- decays to J/Psi phi K+- in the CMS data are also reported. Precision studies of the Bs system and determination of CP-violation sensitive parameters are discussed. Finally the status of the searches for rare decays is presented.
        Orateur: Dr stefania spagnolo (INFN Lecce and Dip. Matematica e Fisica "Ennio De Giorgi", Univ. del Salento)
        Paper
        Slides
      • 14
        Lattice conquest of the Delta I=1/2 Rule and its implications
        Orateur: amarjit soni (BNL)
        Slides
    • Young Scientist Forum

      Young Scientist Forum

      • 15
        Precise measurement of the oscillation frequency in the B0(s)B0(s)bar system
        Orateur: M. Sebastian Wandernoth (Heidelberg University)
        Slides
      • 16
        Measurement of branching fractions and angular observables of B decays to vector-vector
        Orateur: Alvaro Dosil (Univ. Santiago de Compostela)
        Slides
      • 17
        Lepton universality in K decays
        In the Standard Model minimally extended by sterile neutrinos, modified W-l-nu couplings arise and induce a tree-level enhancement to lepton flavour universality violation in light mesons. Indeed the additional mixing between the active neutrinos and the sterile ones can generate deviations from unitarity in the leptonic mixing matrix for charged currents. We recently reconsidered this idea in the context of the inverse seesaw and its impact on the well measured ratios Rk and Rpi. This work (arxiv:1211.3052) shows that the current experimental bound can be saturated while agreeing with the different experimental and observational constraints. I would also present recent results we obtained by applying this idea to other mesons decays with the aim to test the existence of sterile neutrinos to a further extent.
        Orateur: Cedric Weiland (LPT Orsay)
        Proceedings
        Slides
      • 18
        Phenomenology of a U(2)^3 flavour symmetry
        The approximate U(2)^3 symmetry exhibited by the quark sector of the Standard Model, broken in specific directions dictated by minimality (Minimal U(2)^3), can explain the current success of the CKM picture of flavour and CP violation while allowing for large deviations from it at foreseen experiments. The embedding of this symmetry in specific models leaves space to satisfy collider and precision bounds without spoiling the naturalness of the theory. In an extended version of this framework (Generic U(2)^3), if needed, one could account for the recently observed CP asymmetry in D → ππ, KK decays, while being consistent with all the other constraints.
        Orateur: Filippo Sala (Scuola Normale Superiore and INFN, Pisa)
        Paper
        Slides
  • lun. 4 mars
    • Top & Dark Matter

      Monday March 4th : Top & Dark Matter

      • 19
        Top Physics in LHC
        An overview of recent results on top quark properties and interactions is given, obtained using data collected with the CMS and ATLAS experiments during the years 2011 and 2012 at 7 TeV and 8 TeV center-of-mass energies. Measurements of top quark pair production cross sections in several top quark final states are reported. Moreover, cross sections for the electroweak production of single top quarks in both t- and tW-channels are shown. The mass of the top quark is extracted using several methods. Presented results also include measurements of the W helicity in top decays, the top pair charge asymmetry, the top quark charge and the search for anomalous couplings. Experimental outcomes are compared with standard model predictions and a combination of measurements between the different LHC experiments is reported when available
        Orateur: Dr Carlo Battilana (CIEMAT)
        Paper
        Slides
      • 20
        TeVatron top quark production and properties
        Orateur: Jonathan Wilson (University of Michigan)
        Slides
      • 21
        TeVatron results on single top
        Orateur: Dr Aran Garcia Bellido (University of Rochester, USA)
        Slides
      • 22
        Recent results from AMS
        Orateur: Dr Bruna Bertucci (University of Perugia and INFN)
        Slides
      • 09:55
        Tea or Coffee break
      • 23
        Indirect searches for dark matter with the Fermi Large Area Telescope
        High energy gamma-rays are one of the most promising ways to constrain or reveal the nature of dark matter. After the four year of the Fermi LAT mission, indirect constraints on the dark matter cross section to various particle channels are moving well into the theoretically motivated region of the parameter space. I will present an overview of the recent Fermi LAT dark matter and relevant astrophysical results and comment on the prospects for the near term improvements.
        Orateur: Dr Gabrijela Zaharijas (ICTP and INFN Trieste)
        Slides
      • 24
        Fermi-LAT limits on mass degenerate dark matter scenarios
        Orateur: Prof. Alejandro Ibarra (Technische Universität München)
        Paper
        Slides
      • 25
        Long-lived higgsinos as probes of gravitino dark matter at the LHC
        An MSSM scenario in which two higgsino-like neutralinos and a higgsino-like chargino are light (of the order 100 GeV) and the other superparticles heavy (TeV-scale masses) is an interesting theoretical possibility. Such a spectrum can be obtained in GUT models and is consistent with a Higgs mass of $\sim 126$ GeV and the absence of LHC signals for any other new physics so far. Because the higgsinos are nearly mass degenerate and the strongly interacting superparticles are out of reach, such a scenario is difficult to probe at the LHC. The prospects change if we allow for a small amount of R-parity violation, which leads to a consistent cosmology with gravitino dark matter. The limits on decaying gravitino dark matter from gamma-ray searches with the Fermi-LAT put a lower bound on the higgsino NLSP decay length, giving rise to a displaced-vertex collider signature. I will present a detector-level study of the prospects for detection with the 8 TeV LHC data.
        Orateur: Dr Sara Rydbeck (DESY)
        Slides
    • Top & Dark Matter

      Monday March 4th : Top & Dark Matter

      • 26
        Dark matter searches : Bolometer review
        Orateur: Dr Nader Mirabolfathi (University of California, Berkeley)
        Paper
        Slides
      • 27
        Status of the Inert Doublet Model and Scalar Portals
        Orateur: Dr Michel Tytgat (ULB - Université Libre de Bruxelles)
        Paper
        Slides
      • 28
        Flavored dark matter versus scalar portal
        In my talk, I will consider dark matter candidates corresponding to new scalar degrees of freedom coupling to quarks in a way consistent with minimal flavor violation hypothesis. I will discuss the experimental constraints on the viable parameter space of these models and explain how their phenomenology can differ from the scalar dark matter models with a coupling to quarks through SMS portal only.
        Orateur: Mlle Laura Lopez Honorez (Univ. Libre de Bruxelles Belgium)
        Slides
      • 18:10
        Tea or Coffee break
      • 29
        Direct Dark Matter search with the XENON program
        Astronomical and cosmological observations indicate that a large amount of the energy content of the Universe is made of dark matter. Particle candidates, under the generic name of Weakly Interacting Massive Particles (WIMPs), arise naturally in many theories beyond the Standard Model of particle physics. The XENON100 detector, the current phase of the XENON direct dark matter search program, is a dual phase time-projection chamber operated at the Laboratori Nazionali del Gran Sasso (LNGS), that aims to detect galactic dark matter through the elastic nuclear scattering of WIMPs from xenon target nuclei. We present in detail the analysis procedure and the results from Run10 data, the latest science data run (lasting for 13 months during 2011 and 2012), focusing on the spin-independent WIMP-nucleon interaction. A blind analysis of 224.6 live days 34 kg exposure has yielded no evidence for dark matter events. Thanks to the ultra-low electromagnetic background of the XENON100 detector, about 5 x 10^-3 events (kg day keV)^-1, our collaboration has set the most stringent limit to date, excluding spin-independent WIMP-nucleon cross-sections above 2 x 10^-45 cm^2 for a 55 GeV/c^2 WIMP mass at 90% confidence level. In addition, we show further ongoing analyses and describe the status and physics goal of XENON1T, the next phase of the program.
        Orateur: Dr Paolo Beltrame (Weizmann Institute of Science)
        Paper
        Transparents
      • 30
        Recent results from Ice Cube
        Orateur: Nathan Whitehorn (University of Wisconsin - Madison)
        Paper
        Slides
    • Young Scientist Forum

      Young Scientist Forum

      • 31
        125 GeV Scalar Bosons in 2 doublet models
        The current Higgs boson data at 125 GeV state appears to exhibit a substantial excess in the di-photon final state, whereas a more or less SM-like rate is observed in the ZZ decaying to four lepton channel. Beyond the SM, the two-Higgs-doublet model (2HDM) containing a second Higgs doublet is one of the simplest extensions. We examine the maximum Higgs signal enhancements that can be achieved in the 2HDM (when either a single Higgs or multiple Higgses have mass(es) near 125 GeV). In general, the constraints of vacuum stability, unitarity and perturbativity play the key role in restricting possibilities for signal enhancement. The Type II model allows for an enhancement in the di-photon rate (relative to the SM) of the order of 2-3 but associated with an even larger ZZ signal, a situation disfavored by the LHC observations. In contrast, the maximal value for the di-photon signal in the Type I model can reach the order of 1.3 for which the ZZ signal is of order 1, both being consistent with the current data.
        Orateur: M. Yun Jiang (UC Davis)
        Paper
        Slides
      • 32
        Search for $B_s^0 \to \mu^+ \mu^-$ at D0
        An updated on the search for the rare decay $B_s^0 \to \mu^+ \mu^-$ using data collected by the D0 detector at the Fermilab Tevatron collider. This analysis covers the full Run II data set, corresponding to approximately 10.4 fb$^{-1}$ of integrated luminosity in $p\bar{p}$ collisions at $\sqrt{s} = 1.96$ TeV.
        Orateur: Mme Michelle Prewitt (Rice University)
        Slides
      • 33
        Constraints on Universal extra dimensions from Scalar boson searches
        Orateur: Takuya Kakuda (Niigata University)
        Slides
      • 34
        The discovery potential of a Linear Collider for charged Lepton Flavour Violation in the SUSY seesaw
        In addition to explaining neutrino masses and mixings (neutral lepton flavour violation - LFV), some mechanisms of neutrino mass generation can also give rise to potentially observable LFV in the charged lepton sector (cLFV). By focusing on the supersymmetric version of the type-I seesaw mechanism, we address the potential of a Linear Collider operating with polarisable e-plus e-minus as well as e-minus e-minus beams for the discovery of cLFV in e-mu flavour transitions.
        Orateur: M. António Figueiredo (CFTP / IST-ID & LPC Clermont)
        Paper
        Slides
      • 35
        Measurement of the $t$-channel single top-quark cross sections with the ATLAS detector
        The production of single top quarks at the LHC is dominated by the t-channel exchange of a virtual W boson that is emitted by a light quark inside one of the colliding protons. Thus, the measurement of the top-quark and top-antiquark production cross sections is sensitive to the u-quark PDF and the d-quark PDF and can provide complementary input to constrain these PDF, complementary to other high-$p_T$ processes. Furthermore, the cross section is proportional to the square of the CKM matrix element |V_tb| and the measurement can thus provide additional input to constrain the quark mixing matrix without assumptions on the number of quark generations. In this measurement neural networks are used to separate the $t$-channel signal from the backgrounds after an event selection. Results for $t$-channel single top-quark production are presented at a center of mass energy of $\sqrt(s) = 7 \tev$ and $\sqrt(s) = 8 \tev$.
        Orateur: Kathrin Becker (University of Wuppertal (ATLAS))
        Paper
        Slides
      • 36
        Charged lepton flavor violation processes in the extended standard model with operators of dimension six
        The standard model (SM)theory is considered as a low energy approximation of some more fundamental theory. In this theory lepton flavor is conserved. Here we investigate the possibility of charged lepton flavor violation for the decay of $\mu \to e \gamma$ and $\mu \to eee$ in the extended SM, including dimension six.
        Orateur: Mme Saereh Najjari (University of Warsaw)
        Paper
        Slides
  • mar. 5 mars
    • Neutrinos

      Tuesday March 5th:Neutrinos

      • 37
        Recent results from T2K
        The T2K experiment is a long baseline neutrino experiment. The baseline is the 295 km from the J-PARC accelerator in Tokai to Super-Kamiokande. We will present our results using data taken from Jan. 2010 to Jul. 2012. This data corresponds to about 4% of our ultimate statistics. I will show the results of the muon neutrino disappearance measurement and the electron neutrino appearance measurement. Since the muon neutrino disappearance results have just been updated this winter, that will be my primary focus.
        Orateur: Dr Motoyasu Ikeda (Kyoto University)
        Transparents
      • 38
        Results of OPERA
        The OPERA experiment has been designed to perform the first detection of neutrino oscillations in the Nu_mu-->Nu_tau channel, in direct appearance mode through the event by event detection of the tau lepton produced in Nu_tau Charged Current interactions. OPERA is a hybrid detector, made of emulsion/lead target elements and of electronic detectors, placed in the CNGS muon neutrino beam from CERN to Gran Sasso, 730 km away from the source. Neutrino interactions from the CNGS neutrino runs have been recorded from 2008 until the end of 2012. We shall report on the data sample analysed so far and give the latest OPERA results on Nu_mu-->Nu_tau and Nu_mu-->Nu_e oscillation searches.
        Orateur: Pablo DEL AMO SANCHEZ (LAPP, Université de Savoie, IN2P3 - CNRS)
        Paper
        Transparents
      • 39
        Recent Results from the Daya Bay Reactor Antineutrino Experiment
        The Daya Bay experiment is designed to measure the smallest neutrino mixing angle θ13 precisely using reactor anti-neutrinos. It is located at the Daya Bay Nuclear Power Complex in southern China, and consists of eight antineutrino detectors deployed in three underground experimental halls at different baselines from three clusters of nuclear reactors. Low-energy electron anti-neutrinos emitted from the cores are detected, and a value of sin^2(2θ13) is determined by comparing the observed rate in the far detectors with the predicted one based on the measured rates obtained from the near detectors. This kind of relative measurement can reduce the systematic uncertainties significantly. Daya Bay began physics data taking since Dec 24, 2011, and reported the first discovery of a non-zero value for sin^2(θ13) with more than five standard deviations in March 2012. The recent results and prospects of Daya Bay will be presented in this talk.
        Orateur: Dr Guofu Cao (IHEP, China)
        Transparents
      • 40
        Measurement of Theta-13 Using a Delayed Neutron Capture on Hydrogen in Double Chooz
        Double Chooz is a reactor antineutrino experiment built to measure a mixing angle theta-13. The experiment uses two detectors at different baselines (400 m and 1 km) to precisely measure the disappearance of electron flavor anti-neutrino from the Chooz reactor cores in Ardenne, France. Our inverse beta decay (IBD) signal is a two-fold coincidence of a prompt positron followed by a delayed neutron capture on Gadolinium (Gd). The delayed neutron capture releases 8 MeV of energy from multiple gamma rays and is easily distinguished from natural radioactive backgrounds. This signal extraction channel is common to all currently running reactor based experiments. In this talk, a new approach which uses a delayed neutron capture on Hydrogen will be presented with the latest result. The latest result from the standard approach will be also presented in comparison. While delayed neutron capture on Gd is used in all the reactor-based $¥theta_{13}$ measurements, it is also possible to detect IBD via delayed neutron capture on Hydrogen. In Double Chooz the Hydrogen detection channel has twice the signal statistics as the Gd detection channel and provides an independent data sample with which to cross-check the Gd analysis result. In this talk, I present the result of $¥theta_{13}$ measurement from the Hydrogen analysis together with the updated $¥theta_{13}$ results from the main Gd analysis method.
        Orateur: M. KAZUHIRO TERAO (Ph.D Student)
        Transparents
      • 41
        Neutrinos and charge lepton mixings
        Orateur: Mlle Belen Gavela (Madrid autonoma Univ.Spain)
        Transparents
      • 10:20
        Tea or Coffee break
      • 42
        Recent Results From KamLAND-Zen
        The KamLAND-Zen experiment is a new application of the KamLAND detector running in parallel with the ongoing antineutrino program at KamLAND. The experiment searches for neutrinoless double beta decay of $^{136}$Xe using a target of Xe-loaded liquid scintillator placed at the center of the KamLAND detector. KamLAND-Zen recently completed its first phase of running, corresponding to the largest exposure of $^{136}Xe to date: 89.5 kg-yr. Based on the first-phase dataset the collaboration obtains a lower limit for the neutrinoless double-beta decay half-life of $^{136}$Xe: $T_{1/2}_{0\nu} > 1.9 \times 10^{25} $ yr at 90% C.L. Combining limits from KamLAND-Zen and EXO-200 gives $T_{1/2}_{0\nu} > 3.4 \times 10^{25}$ yr at 90% C.L. Following a brief overview of neutrinoless double beta decay experiments I will describe the KamLAND-Zen detector, the results of the first phase data set and their implications for the neutrinoless double-beta decay detection claim in Ge-76 reported by a part of the Heidelberg-Moscow collaboration.
        Orateur: Dr Thomas ODonnell (UC Berkeley / Lawrence Berkeley National Lab)
        Paper
        Transparents
      • 43
        The Discrete road to lepton masses and mixings
        Orateur: Daniel Hernandez (The Adbus Salam ICTP Trieste)
        Transparents
    • Neutrinos

      Tuesday March 5th:Neutrinos

      • 44
        Recent results from Gerda
        The GERmanium Detector Array (GERDA) experiment searches for the neutrinoless double beta decay of Ge-76. It is a lepton-violating process which can shed light on the Dirac vs. Majorana nature of the neutrino. The experiment is located at the Gran Sasso Undergound Laboratory (LNGS) of INFN, Italy. High-purity Germanium detectors enriched in the isotope 76 are operated bare in liquid argon, that serves as cooling medium and shields against external radiation. Data taking for the Phase I of the experiment began on Nov. 2011. Latest results, including resolutions, background levels and a measurement of the half-life of the neutrino-accompained double beta decay of Ge-76 will be presented.
        Orateur: M. Paolo Zavarise (INFN/LNGS)
        Slides
      • 45
        Precision measurement of the Beryllium-7 line with the Borexino detector
        The Borexino experiment was the first to directly investigate the sub-MeV region of the solar spectrum. Its search for answers to some fundamental questions in the field of neutrino oscillations was accomplished with a precision measurement of the $^{7}$Be line at 5\%; Borexino detected 46.0$\pm1.5_{\rm stat}$$^{+1.6}_{-1.5\,\rm syst}$ solar neutrino events/day/(100 tons) during Phase I of data taking. Further investigation of the signal led to the determination of day-night asymmetry that resulted in no significant variation; the detected asymmetry of 0.001$\pm0.012_{\rm stat}$$\pm0.007_{\rm syst}$ is consistent with zero within the error. In this talk I will focus on the precision measurement of the $^{7}$Be line including the first release of the solar neutrino annual flux modulation in Borexino. Consistent with the expectations results give us the confidence that the signal is in fact coming from the Sun. We also look forward to new results in Phase II that bring remarkably low background levels and new sensitivity.
        Orateur: M. Szymon Manecki (Virginia Tech Ins. and State U.)
        Slides
      • 46
        Neutrino mass hierarchy at large detectors
        We study the possibility to perform neutrino oscillation tomography and to determine the neutrino mass hierarchy in kilometer-scale ice Cerenkov detectors by means of the theta13-driven matter effects which occur during the propagation of atmospheric neutrinos deep through the Earth. We consider the ongoing IceCube/DeepCore neutrino observatory and future planned extensions, such as the PINGU detector, which has a lower energy threshold. Our simulations include the impact of marginalization over the neutrino oscillation parameters and a fully correlated systematic uncertainty on the total number of events.
        Orateur: Dr Sergio Palomares-Ruiz (IFIC-CSIC / CFTP-IST)
        Paper
        Slides
      • 47
        Exploring Neutrino Physics with the Cosmic Microwave Background
        The constraints from recent observations of the Cosmic Microwave Background (CMB) on neutrinos are considered. Results are discussed both with CMB information only as well as in conjunction with other tracers of large scale structure.
        Orateur: M. Brent Follin (University of California, Davis)
        Slides
      • 18:20
        Tea or Coffee break
      • 48
        Light sterile neutrinos in cosmology
        Recent cosmological data favor additional relativistic degrees of freedom beyond the three active neutrinos and photons. Light sterile neutrinos are prime candidates for such additional radiation. I will discuss the evolution of light sterile neutrinos in the early universe, their role as dark-radiation candidates and present cosmological constraints.
        Orateur: Dr Irene Tamborra (MPI for Physics, Munich)
        Paper
        Slides
      • 49
        Results of EXO
        EXO-200 is a double beta decay experiment, that uses ~200kg of liquid Xe, enriched to ~80% Xe-136, in a cylindrical time projection chamber. EXO-200 is located at the WIPP facility near Carlsbad, New Mexico. Double beta decay is a second order weak process in the Standard Model (A,Z)X $->$ (A,Z+2)Y +2e + 2nu (2 neutrino double beta decay) and has been measured with 11 even-even isotopes. The first measurement in Xe-136 was made by EXO-200 in 2011, with a half-life of (2.23\pm0.017 stat.\pm0.22 sys)x10^{21}y, which is the longest lived decay directly observed. If the neutrino has a Majorana mass, then it will be allowed to decay via neutrinoless double beta decay (A,Z)X ->(A,Z+2)Y +2e, which violates B-L symmetry. The rate of 0 neutrino double beta decay is related to the Majorana mass of the neutrino. In this talk I will discuss EXO-200 result from summer 2012 for the 0 neutrino double beta decay half-life of greater than 1.6 x 10^{25}y (90% CL), which, depending on the nuclear matrix model used, gives a Majorana neutrino mass of 140-380meV. I will also talk about future physics with EXO-200 and the planed tonne scale Xe-136 detector nEXO.
        Orateur: Dr David Auty (University of Alabama)
        Paper
        Slides
      • 50
        First measurements with the CUORE-0 prototype
        CUORE-0 is a neutrinoless double beta decay experiment consisting of an array of 52 TeO2 bolometers for a total detector mass of about 40 kg. Its goal is to investigate the Majorana electron neutrino mass in the range expected for the Quasi Degenerate scenario, while providing a test of proof for the future CUORE experiment. This will be a 1-ton array designed to reach a sensitivity into the Inverted Hierarchy region of the neutrino mass spectrum and foreseen to run into operation by end 2014. The first measurements performed with CUORE-0 and the obtained performances will be illustrated, together with a presentation of the CUORE status and of its potentialities in the field of neutrinoless double beta decay research.
        Orateur: Mlle Silvia Capelli (Milano Bicocca Univ. Italy)
        Paper
        Slides
    • Young Scientist Forum

      Young Scientist Forum

      • 51
        Futures Perspect in Neutrino Physics: the LAGUNA-LBNO case
        In future decades, AstroParticle and Neutrino Physics programs are going to be combined within a single experiment. This requires the development of techniques, new infrastructures and a new concept of Detector: next years will be the era of Giant (50-600 kt) Multipurpose Detectors. In particular, 45 European Institutions, connecting scientists with industrial support, are involved in the Design Study LAGUNA-LBNO aiming to the feasibility study of a new large European underground infrastructure for the observation of proton decay, low-energy neutrinos and Beta-Beam and Super-Beam neutrinos from CERN. This last topic will allow the measurements of the still unknown CP violation phase in the lepton sector and the neutrino mass hierarchy. Three detector techniques are currently under study: Liquid Argon (GLACIER), Liquid Scintillator (LENA) and Water Cherenkov (MEMPHYS). Two sites are investigated at the moment: the Pyhasalmi (Finland) mine at a distance of 2300 km from CERN and the Fréjus Laboratory (LSM) at a distance of 130 km from CERN. The LAGUNA-LBNO program gives the first priority to the Liquid Argon detector at Pyhasalmi (with the possibility of adding the LENA detector for the very low energy physics) and the second priority to the MEMPHYS detector at Fréjus. The collaboration efforts are now focused in two directions: the detailed studies of the three detector performances and the evaluation of cost, safety and operation for the excavation and the construction in both sites.
        Orateur: Margherita Buizza Avanzini (Laboratoire APC)
        Paper
        Transparents
      • 52
        Three-generation baryon and lepton number violation at the LHC
        While stringent constraints have been obtained at low energies, systematic and direct tests of the baryon and lepton number conservations have not been carried out at the current energy frontier. We observe that the flavour symmetries of the Standard Model gauge sector, broken as they are in the Standard Model Yukawa one, naturally suppress baryon and lepton number violation at low energy and, simultaneously, make it accessible at the LHC through resonant processes involving at least six fermions, from all three generations. We establish a model independent classification of such transitions and identify two classes that give rise to particularly clean LHC signatures, namely [t mu+ e+] and [tbar tbar + jets].
        Orateur: Gauthier Durieux (CP3 − UCLouvain)
        Paper
        Transparents
      • 53
        Rate-Only analysis with reactor-off data in the Double Chooz experiment
        Among ongoing reactor-based experiments, Double Chooz is unique in obtaining data when the reactor cores are brought down for maintenance. These reactor-off data allow for a clean measurement of the backgrounds of the experiment, thus being of uppermost importance for the theta13 oscillation analysis. While the oscillation results published by the collaboration in 2011 and 2012 rely on background models derived from reactor-on data, in this talk we present an independent study based on the handle provided by 7.53 days of reactor-off data. A global fit to both theta13 and the total background is performed by analyzing the observed neutrino rate as a function of the non-oscillated expected rate for different reactor power conditions. The result presented in this talk is fully consistent with the one already published by Double Chooz. As they both yield almost the same precision, this work stands as a prove of the reliability of the background estimates and the oscillation analysis of the experiment.
        Orateur: Dr Pau Novella Garijo (CIEMAT)
        Paper
        Slides
      • 54
        2-photon decay rate of the Scalar boson in the Inert Doublet Model
        Loop induced 2-photon decay of the Standard Model (SM)-like scalar boson, being sensitive to the existence of new charged particles, may provide insight into the scalar sector of extensions of the SM as well as some constraints on the parameter space thereof. Motivated by experimental hints on the possibility of deviating from the SM predictions of the 2-photon decay rate of the SM-like scalar boson, the analysis of this rate in the framework of the Inert Doublet Model is presented. For the SM-like scalar boson mass equal 125 GeV, and taking into account the following constraints: vacuum stability, existence of the Inert vacuum, perturbative unitarity, electroweak precision tests and the LEP bounds, the regions in the parameter space where the diphoton decay rate is enhanced were found. The resulting regions are confronted with the allowed values of the Dark Matter (DM) mass. Constraints on the mass of the charged scalar, the DM and scalar couplings are presented.
        Orateur: Mlle Bogumila Swiezewska (University of Warsaw)
        Paper
        Slides
  • mer. 6 mars
    • The SM Scalar boson

      Wednesday March 6th : The SM Scalar boson

      • 55
        Study of Standard Model Scalar Production in Bosonic Decay Channels in CMS
        The status of the Standard Model Higgs Boson search in the bosonic decay channels at the CMS experiment at the LHC will be presented. The results will be based on proton-proton collisions data corresponding to integrated luminosities of up to 5.1 fb-1 at sqrt(s) = 7 Tev and 19.6 fb-1 at sqrt(s) = 8 TeV. The observation of a new boson at a mass near 125 GeV should be confirmed by the analysis of the new data and first measurements of the boson properties will be shown.
        Orateur: Guillelmo Gomez-Ceballos (MIT)
        Paper
        Slides
      • 56
        BEH detection to boson pairs in ATLAS
        Latest studies of Standard Model Higgs to diboson states with the ATLAS experiment are reported. Emphasis will be given to the property measurements (mass, couplings, spin-parity) performed in the different channels.
        Orateur: Dr Fabrice Hubaut (CPPM)
        Paper
        Slides
      • 57
        Robust determination of the scalar boson couplings
        We study the indirect effects of new physics on the phenomenology of the recently discovered state associated to the electroweak symmetry breaking sector. In a model independent framework these effects can be parametrized in terms of an effective Lagrangian at the electroweak scale. In a theory in which the SU(2)_L x U(1)_Y gauge symmetry is linearly realized they appear at lowest order as dimension-six operators, containing all the SM fields including the light scalar doublet, with unknown coefficients. We discuss the choice of operator basis which allows us to make better use of all the available data to determine the coefficients of the new operators. We illustrate our present knowledge of those by performing a global 5-parameter fit to the existing data which allows simultaneous determination of the Higgs couplings to gluons, electroweak gauge bosons, bottom quarks, and tau leptons.
        Orateur: Oscar Jose Pinto Eboli (Universidade de São Paulo)
        Slides
      • 58
        Operators evolution and the Standard Model Scalar -> 2gamma
        Orateur: Prof. Elisabeth Jenkins (University of California - San Diego)
        Paper
        Slides
      • 10:15
        Tea or Coffee break
      • 59
        Tevatron SM Scalar Boson results - updated inputs and individual combinations
        The CDF and D0 experiments at the Tevatron $p\bar{p}$ Collider were collecting data between 2002 and 2011. During that time, the extensive search for the standard model Higgs boson was performed. Every accessible decay mode was investigated. Results from the searches for the standard model Higgs boson with the final dataset will be presented for individual channels, as well as combined results from CDF and D0 experiments individually.
        Orateur: Dr Lidija Zivkovic (LPNHE)
        Paper
        Slides
      • 60
        Study of BEH Production in Fermionic decay channels in CMS
        The latest results of the search for the SM scalar boson in fermionic decay channels at the CMS experiment are presented. The dataset used corresponds to an integrated luminosity of 5 fb-1 of pp collision data collected at sqrt(s) = 7 TeV and up to 19.4 fb-1 collected at sqrt(s) = 8 TeV. The analyses described include the searches for the SM scalar boson decaying to tau pairs and to a pair of b-quarks. The compatibility of the results with the observation of a new boson at a mass near 125 GeV will be discussed. Results from the search for MSSM neutral Higgs bosons decaying to fermions will also be briefly summarized.
        Orateur: Mlle Valentina Dutta (MIT)
        Slides
      • 61
        Searches for the BEH boson into fermions at ATLAS
        The discovery of a Higgs-like boson by the ATLAS collaboration relies on evidence from di-boson decays: γγ, ZZ∗ and WW∗. The Standard Model predicts that the Higgs boson with mH∼125GeV should also have significant branching ratios to pairs of bottom and charm quarks and tau-leptons and muons. Decays to these final states are significantly more challenging to detect due to large backgrounds, and hence the requirement to search for associated production of the Higgs boson. I will review searches from ATLAS for the Standard Model Higgs boson into fermions: H→μ+μ−, H→τ+τ− and H→bbˉ, in association with top-quark pairs and vector bosons.
        Orateur: Dr Victoria Martin (University of Edinburgh)
        Files for proceedings
        Paper
        Slides
    • The SM Scalar boson

      Wednesday March 6th : The SM Scalar boson

      • 62
        Maximal deviations of the scalar boson couplings if no further particle is seen
        In the light of the discovery of a Higgs boson like particle and no evidence of particles beyond the Standard Model the question arises: How much can the coupling of the Higgs boson to other particles deviate from the Standard Model Higgs couplings if no further particles will be discovered at the LHC and how precise have Higgs coupling measurements to be to capture these deviations? In the context of three different models (a model with a singlet Higgs boson mixed-in, a composite Higgs boson model and the Minimal Supersymmetric Standard Model) these questions will be answered in the talk.
        Orateur: Heidi Rzehak (CERN)
        Slides
      • 63
        Tevatron Combination and BEH Properties
        The Tevatron combination of searches for BEH boson and studies of its properties will be presented. The searches use up to 10 fb-1 of Tevatron collider Run II data. We observe a significant excess of events in the mass range between 115 and 140 GeV/c2. The local significance corresponds to 3.1 Gaussian standard deviations at the mass of 125 GeV/c2. Furthermore, we separately combine searches for BEH boson decaying to bbbar, tau pairs, W pairs, and photon pairs. The observed signal strengths in all channels are consistent with the expectation for the coupling of a SM Scalar boson of 125 GeV/c2.
        Orateur: Wei-Ming Yao (LBL USA)
        Paper
        Slides
      • 64
        Electroweek symmetry breaking and the SM Scalar: Confronting Theories at Colliders.
        Orateur: Dr Aleksandr Azatov (Università di Roma "La Sapienza")
        Paper
        Slides
      • 65
        Combination of results on the BEH Boson in Atlas.
        The combination of the most updated results on the Higgs boson, obtained by the Atlas collaboration, will be presented.
        Orateur: Dr BRUNO MANSOULIE (CEA-SACLAY)
        Paper
        Slides
      • 18:25
        Tea or Coffee break
      • 66
        Scalar potential and stability
        Orateur: Alessandro Strumia (Pisa Univ & INFN & NICPB)
        Slides
      • 67
        Stabilization of the electroweak vacuum by a scalar threshold effect
        Recent studies have shown that, for the current experimental values of M_H, M_t and \alpha_s, the SM scalar potential develops a second minimum, deeper than the electroweak (EW) one. I will review a simple and efficient mechanism to stabilize the EW vacuum. The mechanism involves an extra scalar singlet and can be operative in existing see-saw, invisible axion and unitarized Higgs inflation models.
        Orateur: M. Joan Elias-Miro (IFAE)
        Paper
        Slides
      • 68
        Combination and interpretation of Scalar Boson search results from CMS
        Results are presented on the measurement of the properties of the new state that was discovered in the search for a Higgs boson. These include combined measurements of the mass of the new state as well as its tensor structure (spin, CP) and coupling to other particles, using the 7 and 8 TeV datasets of pp collisions.
        Orateur: Dr Mingshui Chen (University of Florida)
        Paper
        Slides
  • jeu. 7 mars
    • Beyond the SM

      Thursday March 7th: Beyond the SM

      • 69
        European Strategy for Particle Physics
        The first European Strategy for Particle Physics was adopted by CERN Council in July 2006. Since then the physics landscape has evolved in an exciting way, and a complete update of the strategy has been initiated end of 2011, with broad involvement of the community during 2012. The main issues and highlights from the proposed new strategy statements, which will still have to be formally approved by Council, will be presented.
        Orateur: Dr Peter Jenni (CERN)
        Slides
      • 70
        The electroweak fit after the discovery of a new boson at the LHC
        In view of the discovery of a new boson by the ATLAS and CMS collaborations at the LHC, we present an update of the global Standard Model (SM) fit to electroweak precision data. Assuming the new particle to be the SM Higgs boson, all fundamental parameters of the SM are known allowing, for the first time, to overconstrain the SM at the electroweak scale and assert its validity. Within the SM the W boson mass and the effective weak mixing angle can be accurately predicted from the global fit. The results are compatible with, and exceed in precision, the direct measurements. An updated determination of the S, T and U parameters, which parametrise the oblique vacuum corrections, is given. The obtained values show good consistency with the SM expectation and no direct signs of new physics are seen. We conclude with an outlook to the global electroweak fit for a future e+e- collider.
        Orateur: Roman Kogler (University of Hamburg)
        Slides
      • 71
        SUSY confronting data: MSSM versus NMSSM
        The usual SUSY fit requirements today include direct limit on SUSY searches, relic abundance of Dark matter, direct DM searches, Higgs mass, rare decays (including B->mumu) and Higgs decay branching ratios. Assumimg the latter ones are close to that of the SM one can fit all these requirements in the MSSM, albeit with heavy stops. The NMSSM provides much wider possibilities including varying branching ratios, but require some non-universality at the GUT scale. In this case one typically has two Higgses with the masses around 100 and 125 GeV and the third one not too heavy. We explore both these models and define the allowed regions of parameter space both in (m0-m1/2) plane (MSSM,NMSSM) and in (lambda-kappa) plane (NMSSM). For MSSM the most stringent requirement happens to be the Higgs mass, that restricts the values of m1/2 above ~1000 GeV. For the NMSSM in the (lambda-kappa) plane the applied constraints single out a small spot, while the (m0-m1/2) plane is almost open above m1/2>400 GeV. We discuss several scenario including small and large tan beta and various possibilities for the Higgs masses.
        Orateur: Prof. Dmitri Kazakov (JINR)
        Slides
      • 72
        Search for 3rd generation and gluino induced SUSY production
        In this talk, the latest results from CMS and ATLAS on searches for gluino induced and direct third generation SUSY production, in a variety of complementary final state signatures and methods, will be presented using up to 20/fb of data from the 8 TeV LHC run of 2012. SUSY models with relatively light top and bottom squarks are particularly appealing, especially given the recent Higgs-like boson discovery, as they provide a solution to the little-hierarchy problem.
        Orateur: Dr Jad Marrouche (Imperial College London)
        Slides
      • 10:10
        Tea or Coffee break
      • 73
        SUSY and constraints on (extra) Scalar masses (MSSM and variants)
        Orateur: Prof. Marcella Carena (Fermilab)
        Slides
      • 74
        Search for EWKino production and long-lived particles at the LHC
        The Large Hadron Collider has extended the reach of particle-physics experiments with a potential for discovery of new physics at the TeV scale. Many models of physics beyond the Standard Model predict new particles with long lifetimes. Examples include supersymmetry with R-parity violation, suppressed decays of the next-to-lightest supersymmetric particle, or models with hidden sectors. The decay vertices of particles with lifetimes of order 10 ps to 10 ns can be efficiently identified by the ATLAS and CMS detectors. In addition, in quark and gluons collisions it is easy to produce coloured objects like gluinos and squarks, which decay typically to jets and missing energy (MET), while the cross section for Electroweak production is smaller. These "ewkino" decays typically produce many leptons and MET. The searches for these decays are generally based directly or indirectly on MET analysis. A review of the search for such particles, including methods for reconstruction and background suppression and the expected sensitivity of the search using 2012 data collected by LHC is reported.
        Orateur: Dr Monica verducci (University of Washington)
        Paper
        Transparents
    • Beyond the SM

      Thursday March 7th: Beyond the SM

      • 75
        Status of SUSY with extra singlets (NMSSM)
        We show that, in supersymmetry with extra singlets, it is easy and natural to obtain a mass of the BEH scalar of ~125 GeV, well above M_Z. Moreover the signal rate in the gamma gamma channel can be enhanced w.r.t. the Standard Model for several reasons. These properties persist in various singlet extensions of the MSSM, which are briefly scetched. Correlations among signal rates in different channels are discussed and, finally, the impact of an extra singlet (singlino) on searches for supersymmetry.
        Orateur: Prof. Ulrich Ellwanger (LPT Orsay)
        Paper
        Slides
      • 76
        Search for high-mass resonances and other exotica at the LHC
        With the discovery of the Higgs boson by the ATLAS and CMS collaborations, all the constituents of the Standard Model (SM) of particle physics have been observed. Despite its success, the SM leaves many questions unanswered and that has motivated the many models of physics beyond the SM. These models predict a wide range of new phenomena that is accessible at the LHC. This talk will present recent results of searches by ATLAS and CMS for new phenomena with emphasis on processes that involve new massive resonances.
        Orateur: John Butler (Boston University)
        Paper
        Slides
      • 77
        The cost of gauge coupling unification in minimal SU(5) at 3 loops
        It was shown recently that the original SU(5) gauge theory proposed by Georgi and Glashow, augmented with an adjoint fermionic multiplet, is compatible both with neutrino masses and gauge coupling unification. In particular, the latter predicts the existence of light electroweak triplet states with masses at the TeV scale. We are going to report in talk about the correlation between the triplet masses and the unification scale at the NNLO accuracy. Such accurate predictions are needed in order to match the experimental precision on the determination of the electroweak gauge couplings. Special emphasis will be put on the possibilities to test such a model through the current experiments at the LHC.
        Orateur: Dr Luminita Mihaila (TTP Karlsruhe Institute of Technology)
        Paper
        Slides
      • 18:05
        Tea or Coffee break
      • 78
        Search for extra dimensions, leptoquarks, 4th generation and ttbar resonances
        In this talk, the latest results from the ATLAS and CMS experiments on searches for extra-dimensions, top-antitop resonances, fourth generation signatures and leptoquarks will be presented. The presented searches are performed using proton-proton collisions data at a centre-of-mass energy of 7 and 8 TeV. A large variety of final states are studied, probing many possible extensions of the Standard Model.
        Orateur: Matthieu Marionneau (Univ. of Maryland)
        Slides
      • 79
        A Light Dynamical Scalar Boson
        With the discovery of a Higgs-like resonance at ATLAS and CMS, the understanding of the electroweak symmetry breaking origin seems a much closer goal. A strong dynamics at relatively low scales is still a good candidate. In this talk, the complete effective Lagrangian up to d<6 will be presented, both for the gauge and the flavour sector. Interesting features in the flavour phenomenology will be discussed.
        Orateur: Dr Luca Merlo (Universidad Autónoma de Madrid)
        Paper
        Slides
    • Moriond discussion and Viet-Nam center presentation
  • ven. 8 mars
    • BSM & Electroweak results

      Friday March 8th: BSM & Electroweak results

      • 80
        Beyond the SM scalar boson searches in TeVatron
        Recent results from the Tevatron will be reported on Higgs searches in models beyond the Standard Model. The models include fermiophobic Higgs bosons, the extension of the Standard Model to a 4th generation of fermions and supersymmetric scenarios.
        Orateur: Elemer Nagy (Centre de Physique des Particules de Marseille)
        Papier
        Transparents
      • 81
        Top-down BSM review
        Orateur: Dr Emilian Dudas (Ecole Polytechnique)
        Paper
        Transparents
      • 82
        Single W and Z production and asymmetries at the TeVatron
        We present the most recent $W$ and $Z$ production, asymmetries, and $V$+jets results from the Tevatron collider at $\sqrt{s}$ = 1.96 TeV, analyzing data collected by CDF and DZero detectors between 2002-2011. The results include the measurements of the $W$ and $Z$ bosons properties, include boson $p_T$ and asymmetries measurements, and also the $W$ and $Z$ boson plus jets productions. Those measurements provide the precision tests on the electroweak in Standard Model (SM), and high order theoretical predictions.
        Orateur: Dr Hang Yin (Fermilab)
        Paper
        Slides
      • 83
        Electroweak Measurements with the ATLAS and CMS Experiments
        Highlights of ATLAS and CMS measurements involving the production of heavy electroweak gauge bosons, W and Z, at the LHC will be presented. Cross sections of single W and Z bosons are studied with very high precision and differential in various kinematic variables. The rapidity differential measurements are shown to have a so far unique impact on our knowledge of proton structure with regards to the strange quark density. Furthermore measurements of tau final states, W polarisation and the weak mixing angle will be presented. Various di-boson measurements will be presented. These measurements test the non-Abelian gauge structure and limits on anomalous triple gauge couplings are derived.
        Orateur: Dr samira Hassani (IRFU-SPP/CEA Saclay)
        Paper
        Transparents
      • 10:00
        Tea or Coffee break
      • 84
        Noncommutative Geometry in the LHC-Era
        Noncommutative geometry (NCG) allows to unify the basic building blocks of particle physics, Yang-Mills-Higgs theory and General relativity, into a single geometrical framework. The resulting effective theory constrains the couplings of the Standard Model (SM) and reduces the number of degrees of freedom. After briefly introducing the basic ideas of NCG, I will present its predictions for the SM and the few known models beyond the SM. Most of these models, including the Standard Model, are now ruled out by LHC data. But interesting extensions of the SM which agree with the presumed Higgs mass and predict new particles are still very much alive and await further experimental data.
        Orateur: Dr Christoph Stephan (Universität Potsdam)
        Paper
        Transparents
      • 85
        Diboson Physics at the Tevatron
        We present an overview of the recent results on the production of massive boson pairs in p-pbar collisions at a center-of-mass energy of 1.96 TeV, studied by the CDF and D0 experiments at the Tevatron. The measurements performed are a precise test of the Standard Model and crucial backgrounds for several different searches for new physics. In particular the good knowledge of the diboson production in decay modes involving heavy quarks improved the CDF and D0 sensitivity in Higgs boson searches. The results reported will represent part of the Tevatron legacy, utilizing the complete collected data sample.
        Orateur: Matteo Bauce (Università di Padova - INFN)
        Proceedings
        Transparents
    • BSM & Electroweak results

      Friday March 8th: BSM & Electroweak results

      • 86
        Brane susy breaking and inflation -- implications for scalar fields and CMB distortion
        Brane SUSY Breaking is a peculiar phenomenon that has emerged from the study of orientifold models in String Theory. It occurs whenever the vacuum is to contain different collections of BPS branes whose simultaneous presence breaks supersymmetry at the string scale. It leaves behind scalar fields with exponential potentials that could have injected the inflationary phase of our Universe and have some intriguing indications for the low-frequency tail of the CMB power spectrum.
        Orateur: Augusto Sagnotti (Scuola Normale Superiore)
        Paper
        Slides
      • 87
        New results from the MEG experiment at PSI
        The MEG experiment at PSI is searching for the possible lepton flavor violating decay of a muon into an electron and a positron with unprecedented sensitivity. The existence of this decay would represent an unambiguous sign of new physics beyond the Standard Model. The current best world upper limit of 2.4 x 10**(-12) on the branching ratio of the mu->e gamma decay was published by MEG in 2011. In this talk we present new results based on twice the statistics used in that publication. The current status of the experiment and its future upgrade projects will also be discussed.
        Orateur: Dr Wataru Ootani (ICEPP, University of Tokyo)
        Slides
      • 88
        QCD results at LHC
        Orateur: Dr Niki Saoulidou (University of Athens)
        Slides
      • 18:05
        Tea or Coffee break
      • 89
        Electroweak results from HERA
        The neutral and charged current deep inelastic ep scattering, with longitudinally polarised lepton beams, have been studied with the H1 and ZEUS detectors at HERA. The differential cross sections are measured in the range of four-momentum transfer squared, Q2 , up to 50'000 GeV2, where electroweak effects become clearly visible. The measurements are used to determine the structure function xF_3 and to constrain vector and axial-vector couplings of light quarks to the Z0 boson. The polarisation dependence of the charged current total cross section is also measured. Limits for flavour changing neutral current processes are computed from search for single-top production. The elastic Z0 production cross section is measured to be in agreement with the SM prediction. Limits n new physics phenomena at high Q2 are also derived within the general framework of four-fermion eeqq contact interactions.
        Orateur: Prof. Aleksander Filip Zarnecki (University of Warsaw)
        Archive with proceeding sources
        Paper
        Slides
      • 90
        Discovering Walking Technicolor at LHC,
        Orateur: Koichi Yamawaki (Kobayashi-Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya University)
        Paper
        Slides
      • 91
        Precision measurements of the pi pi gamma and mu mu gamma cross sections with the KLOE detector
        Measurements of the muon magnetic anomaly performed at the BNL have reached an accuracy of 0.54 ppm and the final result differs from Standard Model estimates by 3.2-3.6 standard deviations. The main uncertainty on the theoretical evaluation is due to hadronic loop contributions which are not calculable in perturbative QCD and are obtained from a dispersion integral over the hadronic cross section at low energy. The KLOE experiment at the DAFNE phi-factory in Frascati was the first to exploit Initial State Radiation (ISR) processes for precision measurements of the hadronic cross section below 1 GeV, that accounts for most (70%) of the hadronic contribution to the muon anomaly. In 2005 and 2008 the KLOE collaboration has published two measurements of the pi pi gamma cross section with the ISR photon at small angle, and an independent measurement with the photon emitted at large angle was published in 2011. Recently, a new analysis of KLOE data has been performed which derives the pion form factor directly from the bin-by-bin ratio of pi pi gamma to mu mu gamma cross sections. We present the final results and the comparison with our previous measurements. High-luminosity e+ e- colliders at the GeV scale have been recognized to be ideal environment to search for the U-boson in the Dark Force sector (dark photon). Preliminary results of the U-boson search in the mu mu gamma sample with the exclusion plot in the mass range from 600-1000 MeV are presented.
        Orateur: Dr Caterina Bloise (Laboratori Nazionali di Frascati - INFN)
        Paper
        Slides
    • Young Scientist Forum

      Young Scientist Forum

      • 92
        ZZ cross section measurement at 8 TeV
        The latest measurement of the SM ZZ production cross section at 8 TeV using data recorded by the ATLAS experiment at the Large Hadron Collider is presented. Events are selected consistent with two Z bosons decaying to electrons or muons. The cross section is measured in the experimental fiducial volume and then used to extract the total ZZ production cross section.
        Orateur: Vasiliki Kouskoura (CERN)
        Paper
        Slides
      • 93
        Search for supersymmetry in events with same-sign dileptons, jets and missing transverse momentum with the ATLAS detector
        A search for the production of supersymmetric particles decaying into final states with jets (b-tagged or not), missing transverse momentum and two isolated leptons, e or mu, of the same sign is presented. The analysis uses a data sample collected during 2012, which corresponds to a total integrated luminosity of 21 fb-1 of sqrt{s}= 8 TeV proton-proton collisions recorded with the ATLAS detector at the Large Hadron Collider.
        Orateur: Julien Maurer (CPPM)
        Paper
        Slides
      • 94
        Measurement of the production cross sections of Z/γ* bosons in association with b-jets in pp collisions at √s = 7 TeV with the CMS detector
        The mechanism of production of heavy-flavoured mesons, in association with vector bosons like Z+b in the Standard Model, is only partially understood. The deep understanding of these processes is furthermore required by Higgs and BSM analysis with similar final states. Using the total 5.2 fb-1 LHC proton-proton collision data collected in 2011 at a centre of mass energy of 7 TeV by the CMS detector, the final measurement of the Z+b cross sections will be presented in this talk. Z+b inclusive, Z+1b exclusive and Z+2b inclusive cross sections are determined for b hadron jets having pT > 25 GeV and |eta| < 2.1. The results are related to the following CMS document : Measurement of the production cross sections of Z/γ* bosons in association with b-jets in pp collisions at √s = 7 TeV with the CMS detector, CMS PAS SMP-12-003.
        Orateur: Mlle Ludivine Ceard (UCLouvain)
        Paper
        Transparents
      • 95
        Search for new physics using events with two same-sign isolated leptons in the final state
        Although same sign dileptons final states are very rare in the SM context, they appear naturally in many different new physics scenarios such as SUSY where two same-sign dileptons can be produced in the decay chain of supersymetric particles. Different scenarios can be presented: Same-sign dileptons accompanied by b-quarks can arise from SUSY processes where 3rd generation quark superpartners are lighter that other squarks., resulting in an abundance of top and bottom quarks produced in the cascade decays. In general, same-sign dileptons can be particularly sensitive to SUSY models with compressed spectra where the mass of the LSP is very close to the mass of the produced supersymetric particle, either if it is produced via strong production (squarks or gluinos) when it is accompanied with high hadronic activity or if it is produced via ewk production (charginos or neutralinos) when almost no hadronic activity is present. In all cases the SUSY decay chain ends with the LSP, that escapes undetected and therefore contribute strongly to the MET of the event. We therefore search for SUSY using same sign dilepton events with/out hadronic activity and large missing ET, using the full 2012 integrated luminosity and we interpret our results in the context of various SUSY models.
        Orateur: Santiago Folgueras (Universidad de Oviedo (CMS Collaboration))
        Minutes
        Slides
      • 96
        Search for new heavy neutral bosons decaying into a dilepton pair with the CMS detector at sqrt(s) = 8 TeV.
        Several theories beyond the Standard Model (GUT, large extra dimensions, ...) predict the existence of new heavy bosons. Such particles could be produced in significant amounts at the LHC and their decay into a dilpeton pair provides a clean signature with low background. In this talk we plan to present the results of the analysis of the whole 2012 dataset collected by the CMS experiment at a center of mass energy of 8 TeV. Limits on the upper cross section production of such particles will be presented. These limits can be turned into lower limits on the mass of Z' and graviton, reaching values above 2 TeV for many models.
        Orateur: Laurent Thomas (Université Libre de Bruxelles)
        Paper
        Transparents
      • 97
        Probing spin and parity in WH->lνbb (CDF)
        Orateur: Emily Johnson (Michigan State University)
        Paper
        Slides
  • sam. 9 mars
    • Summaries
      • 98
        Experimental summary
        Orateur: Prof. Paraskevas Sphicas (Athens/CERN)
        Slides
      • 99
        Theory summary
        Orateur: Prof. Fabio ZWIRNER (Univ. and INFN, Padova)
        Paper
        Slides
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