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Tetra- and pentaquarks with charm and bottom quarks at hadron colliders
https://cds.cern.ch/record/2242595
The latest years have seen a resurrection of interest in searches for exotic states motivated by tantalising observations by Belle and CDF. Using the data collected at pp collisions at 7 and 8 TeV by the LHC experiments we present the unambiguous new observation of exotic charmonia tetraquarks and pentaquarks produced in b hadron decays. Recently tetraquarks with a single beauty quark have also be reported by the D0 collaboration. We report about the yet unclear experimental status.Koppenburg, PatrickFri, 20 Jan 2017 14:11:55 GMT2017-01-18LHCb-TALK-2017-008https://cds.cern.ch/record/22425952017008Lattice location of Mg in GaN: a fresh look at doping limitations
https://cds.cern.ch/record/2242570
Radioactive 27Mg (t1/2=9.5 min) was implanted into GaN of different doping types at CERN’s ISOLDE facility and its lattice site determined via beta− emission channeling. Following implantations between room temperature and 800°C, the majority of 27Mg occupies the substitutional Ga sites, however, below 350°C significant fractions were also found on interstitial positions ~0.6 Å from ideal octahedral sites. The interstitial fraction of Mg was correlated with the GaN doping character, being highest (up to 31%) in samples doped p-type with 2E19 cm−3 stable Mg during epilayer growth, and lowest in Si-doped n-GaN, thus giving direct evidence for the amphoteric character of Mg. Implanting above 350°C converts interstitial 27Mg to substitutional Ga sites, which allows estimating the activation energy for migration of interstitial Mg as between 1.3 and 2.0 eV.Wahl, UlrichAmorim, LígiaAugustyns, ValerieGranadeiro Costa, Angelo RafaelDavid Bosne, EricDe Lemos Lima, Tiago AbelLippertz, GertjanMartins Correia, JoaoCastro Ribeiro Da Silva, ManuelKappers, MennoTemst, KristiaanVantomme, AndréDa Costa Pereira, Lino MiguelFri, 20 Jan 2017 11:11:33 GMT20 Jan 2017CERN-OPEN-2017-005https://cds.cern.ch/record/22425702017005Measurement of the $B^{\pm}$ production asymmetry and the $CP$ asymmetry in $B^{\pm} \to J/\psi K^{\pm}$ decays
https://cds.cern.ch/record/2242567
The $B^{\pm}$ meson production asymmetry in $pp$ collisions is measured using $B^+ \to \overline{D}{^0} \pi^+$ decays. The data were recorded by the LHCb experiment during Run 1 of the LHC at centre-of-mass energies of $\sqrt{s}=$ 7 and 8 TeV. The production asymmetries, integrated over transverse momenta in the range $2 < p_{\rm T} < 30$ GeV/$c$, and rapidities in the range $2.1 < y < 4.5$, are measured to be \begin{align*} \mathcal{A}_{\rm prod}(B^+,\sqrt{s}=7~{\rm TeV}) &= (-0.41 \pm 0.49 \pm 0.10) \times 10^{-2},\\ \mathcal{A}_{\rm prod}(B^+,\sqrt{s}=8~{\rm TeV}) &= (-0.53 \pm 0.31 \pm 0.10) \times 10^{-2}, \end{align*} where the first uncertainties are statistical and the second are systematic. These production asymmetries are used to correct the raw asymmetries of $B^{+} \to J/\psi K^{+}$ decays, thus allowing a measurement of the $CP$ asymmetry, \begin{equation*} \mathcal{A}_{CP} (B^+ \to J/\psi K^+)= (0.09 \pm 0.27 \pm 0.07) \times 10^{-2}. \end{equation*}LHCb CollaborationFri, 20 Jan 2017 11:05:52 GMT20 Jan 2017CERN-EP-2016-325https://cds.cern.ch/record/22425672016325Search for Diboson Resonances in the Fully Hadronic Final State Using Jet Substructure Techniques in 8 and 13 TeV Proton-Proton Collisions with the ATLAS Detector
https://cds.cern.ch/record/2242565
In this thesis, searches for narrow resonances decaying into pairs of vector bosons ($WW$, $WZ$ and $ZZ$) are presented. The searches are performed using 20.3 fb$^{-1}$ and 3.2 fb$^{-1}$ of proton-proton collision data collected with the ATLAS experiment at the LHC at centre-of-mass energies of 8 TeV and 13 TeV, respectively. Events are selected in the fully hadronic final state, characterised by two large-radius jets. Requirements on the jet mass and substructure variables are imposed to select large-radius jets that are compatible with the hadronic decay of highly boosted $W$ or $Z$ bosons. A variety of techniques are compared to optimise the identification of boosted vector bosons. The invariant mass spectrum of the two boson-tagged jets is used as discriminating variable to search for a resonant structure on top of the smoothly falling distribution of the background processes. In the analysis performed at 8 TeV, an excess of events is observed for an invariant dijet mass of 2 TeV. The largest deviation from the background prediction occurs in the $WZ$ channel with a global significance of 2.5$\sigma$. On the contrary, no significant deviations from the background expectations are seen in the analysis using 13 TeV $pp$ collisions. Exclusion limits at 95% confidence level are set on the production cross-section times branching ratio for three benchmark models: a bulk Randall-Sundrum model, an extended gauge model and a heavy vector triplet model. $W'$ bosons as predicted in the extended gauge model are excluded in the mass range from 1.3 to 1.5 TeV at 95% confidence level and $W'$ bosons from the heavy vector triplet model are excluded for masses between 1.38 to 1.6 TeV. Delitzsch, Chris MalenaIacobucci, GiuseppeIacobucci, GiuseppeFri, 20 Jan 2017 10:55:31 GMTCERN-THESIS-2016-236https://cds.cern.ch/record/22425652016236Heavy Quark Flavor Physics: Results & Prospects
https://cds.cern.ch/record/2242558
Williams, J MichaelFri, 20 Jan 2017 08:58:18 GMT2016-04-18LHCb-TALK-2016-441https://cds.cern.ch/record/22425582016441Latest Results on Tetra- and Penta-quark Candidates from LHCb: Amplitude Analysis of $\ {B \to J/\psi\phi K}$
https://cds.cern.ch/record/2242556
Britton, Thomas JacksonFri, 20 Jan 2017 08:52:43 GMT2016-04-14LHCb-TALK-2016-440https://cds.cern.ch/record/22425562016440Measurements of Higgs boson production and properties in the ZZ decay channel using the CMS detector
https://cds.cern.ch/record/2242553
Measurements of Higgs boson properties using the Hâ??ZZâ??4l (l = e, Î¼) decay channel are presented, based on a data sample corresponding to an integrated luminosity of 12.9 fbâ??1 of pp collisions at a center-of-mass energy of 13 TeV collected by the CMS experiment at the LHC during 2016. The observed significance for the standard model Higgs boson is 6.2Ï? at a mass of mH = 125.09 GeV, where the expected significance is 6.5Ï?. The signal strength Î¼, defined as the ratio of the Higgs boson production cross section times branching fraction to four leptons to the standard model expectation, is measured to be Î¼ = 0.99 +0.33â??0.26. Individual strength parameters for four Higgs boson production modes are constrained for the first time using this channel. The Higgs boson mass is measured to be mH = 124.50 +0.48â??0.46 GeV. The model-independent fiducial cross section is measured to be 2.29 +0.74â??0.64(stat.) +0.30â??0.23(sys.) +0.01â??0.05(model dep.) fb, and differential cross sections as a function of the transverse momentum of the Higgs boson and the number of associated jets are measured.Regnard, Simon JeanFri, 20 Jan 2017 08:42:09 GMT20 Dec 2016CMS-CR-2016-466https://cds.cern.ch/record/22425532016466Exotic Spectroscopy at LHCb
https://cds.cern.ch/record/2242552
Gao, YuanningFri, 20 Jan 2017 08:41:44 GMT2016-04-19LHCb-TALK-2016-439https://cds.cern.ch/record/22425522016439Search for exotic decays of the 125 GeV Higgs boson using the CMS detector
https://cds.cern.ch/record/2242551
Recent results on searches for exotic Higgs boson decays will be presented in this talk.Cepeda, Maria LuisaFri, 20 Jan 2017 08:41:27 GMT18 Dec 2016CMS-CR-2016-464https://cds.cern.ch/record/22425512016464Overview of ALICE results in pp, pA and AA collisions
https://cds.cern.ch/record/2242545
The ALICE experiment at the Large Hadron Collider (LHC) at CERN is optimized for recording events in the very large particle multiplicity environment of heavy-ion collisions at LHC energies. The ALICE collaboration has taken data in Pb-Pb collisions in Run I and Run II at nucleon-nucleon center-of-mass energies $\sqrt{s_{\text{NN}}}$ = 2.76 and \mbox{5.02 TeV}, respectively, and in pp collisions at center-of-mass energies $\sqrt{s}$ = 0.9, 2.76, 5.02, 7, 8 and 13 TeV. The asymmetric system p-Pb was measured at a center-of-mass energy $\sqrt{s_{\text{NN}}}$ = 5.02 TeV. Selected physics results from the analysis of these data are presented, and an outline of the ALICE prospects for Run III is given.Schicker, R.Fri, 20 Jan 2017 06:23:01 GMT2016-12-28arXiv:1701.04810https://cds.cern.ch/record/2242545['arXiv:1701.04810']arXiv:1701.04810A Simple Method to detect spontaneous CP Violation in multi-Higgs models
https://cds.cern.ch/record/2242544
For models with several Higgs doublets we present an alternative method to the one proposed by Branco, Gerard and Grimus, in 1984, to check whether or not CP is spontaneously violated in the Higgs potential. The previous method is powerful and rigorous. It requires the identification of a matrix $U$ corresponding to a symmetry of the Lagrangian and verifying a simple relation involving the vacuum expectation values. The nonexistence of such a matrix signals spontaneous CP violation. However, as the number of Higgs doublets increases, finding such a matrix $U$ may not be straightforward and it may turn out to be easier to analyse the potential by going to the so-called Higgs basis. The transformation to the Higgs basis is straightforward once the vacuum expectation values are known. The method proposed in this work is also powerful and rigorous and can be particularly useful to analyse models with more than two Higgs doublets and with continuous symmetries.Ogreid, O.M.Osland, P.Rebelo, M.N.Fri, 20 Jan 2017 06:23:00 GMT2017-01-17CERN-TH-2017-008https://cds.cern.ch/record/22425442017008Dimension-6 Operator Analysis of the CLIC Sensitivity to New Physics
https://cds.cern.ch/record/2242543
We estimate the possible accuracies of measurements at the proposed CLIC $e^+e^-$ collider of Higgs and $W^+W^-$ production at centre-of-mass energies up to 3TeV, incorporating also Higgsstrahlung projections at higher energies that had not been considered previously, and use them to explore the prospective CLIC sensitivities to decoupled new physics. We present the resulting constraints on the Wilson coefficients of dimension-6 operators in a model-independent approach based on the Standard Model effective field theory (SM EFT). The higher centre-of-mass energy of CLIC, compared to other projects such as the ILC and CEPC, gives it greater sensitivity to the coefficients of some of the operators we study. We find that CLIC Higgs measurements may be sensitive to new physics scales $\Lambda = \mathcal{O}(10)$TeV for individual operators, reduced to $\mathcal{O}(1)$ TeV sensitivity for a global fit marginalising over the coefficients of all contributing operators. We give some examples of the corresponding prospective constraints on specific scenarios for physics beyond the SM, including stop quarks and the dilaton/radion.Ellis, JohnRoloff, PhilippSanz, VeronicaYou, TevongFri, 20 Jan 2017 06:22:58 GMT2017-01-17KCL-PH-TH-2017-04https://cds.cern.ch/record/2242543201704Recent Developments in CMS Fast Simulation
https://cds.cern.ch/record/2242542
CMS has developed a fast detector simulation package, which serves as a fast and reliable alternative to the detailed GEANT4-based (full) simulation, and enables efficient simulation of large numbers of standard model and new physics events. Fast simulation becomes particularly important with the current increase in the LHC luminosity. Here, I will discuss the basic principles behind the CMS fast simulation framework, and how they are implemented in the different detector components in order to simulate and reconstruct sufficiently accurate physics objects for analysis. I will focus on recent developments in tracking and geometry interface, which improve the flexibility and emulation performance of the framework, and allow a better synchronization with the full simulation. I will then show how these developments have led to an improved agreement of basic analysis objects and event variables between fast and full simulation.Sekmen, SezenFri, 20 Jan 2017 06:22:54 GMT2017-01-13arXiv:1701.03850https://cds.cern.ch/record/2242542['arXiv:1701.03850']arXiv:1701.03850Supergravity and its Legacy
https://cds.cern.ch/record/2242541
A personal recollection of events that preceded the construction of Supergravity and of some subsequent developments.Ferrara, S.Fri, 20 Jan 2017 06:22:54 GMT2017-01-12CERN-TH-2017-004https://cds.cern.ch/record/22425412017004Supersymmetric partition functions and the three-dimensional A-twist
https://cds.cern.ch/record/2242540
We study three-dimensional $\mathcal{N}=2$ supersymmetric gauge theories on $\mathcal{M}_{g,p}$, an oriented circle bundle of degree $p$ over a closed Riemann surface, $\Sigma_g$. We compute the $\mathcal{M}_{g,p}$ supersymmetric partition function and correlation functions of supersymmetric loop operators. This uncovers interesting relations between observables on manifolds of different topologies. In particular, the familiar supersymmetric partition function on the round $S^3$ can be understood as the expectation value of a so-called "fibering operator" on $S^2 \times S^1$ with a topological twist. More generally, we show that the 3d $\mathcal{N}=2$ supersymmetric partition functions (and supersymmetric Wilson loop correlation functions) on $\mathcal{M}_{g,p}$ are fully determined by the two-dimensional A-twisted topological field theory obtained by compactifying the 3d theory on a circle. We give two complementary derivations of the result. We also discuss applications to F-maximization and to three-dimensional supersymmetric dualities.Closset, CyrilKim, HeeyeonWillett, BrianFri, 20 Jan 2017 06:22:50 GMT2017-01-11CERN-TH-2017-006https://cds.cern.ch/record/22425402017006The $\Lambda$-parameter in 3-flavour QCD and $\alpha_s(m_Z)$ by the ALPHA collaboration
https://cds.cern.ch/record/2242539
We present results by the ALPHA collaboration for the $\Lambda$-parameter in 3-flavour QCD and the strong coupling constant at the electroweak scale, $\alpha_s(m_Z)$, in terms of hadronic quantities computed on the CLS gauge configurations. The first part of this proceedings contribution contains a review of published material \cite{Brida:2016flw,DallaBrida:2016kgh} and yields the $\Lambda$-parameter in units of a low energy scale, $1/L_{\rm had}$. We then discuss how to determine this scale in physical units from experimental data for the pion and kaon decay constants. We obtain $\Lambda_{\overline{\rm MS}}^{(3)} = 332(14)$ MeV which translates to $\alpha_s(M_Z)=0.1179(10)(2)$ using perturbation theory to match between 3-, 4- and 5-flavour QCD.Bruno, M.Dalla Brida, M.Fritzsch, P.Korzec, T.Ramos, A.Schaefer, S.Simma, H.Sint, S.Sommer, R.Fri, 20 Jan 2017 06:22:48 GMT2017-01-11CERN-TH-2016-262https://cds.cern.ch/record/22425392016262FRB 121102 Casts New Light on the Photon Mass
https://cds.cern.ch/record/2242538
The photon mass, $m_\gamma$, can in principle be constrained using measurements of the dispersion measures (DMs) of fast radio bursts (FRBs), once the FRB redshifts are known. The DM of the repeating FRB 121102 is known to $< 1$\%, a host galaxy has now been identified with high confidence,and its redshift, $z$, has now been determined with high accuracy: $z = 0.19273(8)$. Taking into account the plasma contributions to the DM from the Intergalactic medium (IGM) and the Milky Way, we use the data on FRB 121102 to derive the constraint $m_\gamma \lesssim 2.2 \times 10^{-14}$ eV c$^{-2}$ ($3.9 \times 10^{-50}$ kg). Since the plasma and photon mass contributions to DMs have different redshift dependences, they could in principle be distinguished by measurements of more FRB redshifts, enabling the sensitivity to $m_\gamma$ to be improved.Bonetti, LucaEllis, JohnMavromatos, Nikolaos E.Sakharov, Alexander S.Sarkisyan-Grinbaum, Edward K.Spallicci, Alessandro D. A. M.Fri, 20 Jan 2017 06:22:47 GMT2017-01-11KCL-PH-TH-2017-01https://cds.cern.ch/record/2242538201701Circular polarisation: a new probe of dark matter and neutrinos in the sky
https://cds.cern.ch/record/2242537
The study of anomalous electromagnetic emission in the sky is the basis of indirect searches for dark matter. It is also a powerful tool to constrain the radiative decay of active neutrinos. Until now, quantitative analyses have focused on the flux and energy spectrum of such an emission; polarisation has never been considered. Here we show that we could be missing out on an essential piece of information. The radiative decay of neutrinos, as well as the interactions of dark matter and neutrinos with Standard Model particles can generate a circular polarisation signal in X-rays or \gamma-rays. If observed, this could reveal important information about their spatial distribution and particle-antiparticle ratio, and could even reveal the nature of the high-energy particle physics processes taking place in astrophysical sites. The question of the observability of these polarised signatures and their separation from background astrophysical sources is left for future work.Bœhm, CélineDegrande, CélineMattelaer, OlivierVincent, Aaron C.Fri, 20 Jan 2017 06:22:45 GMT2017-01-10CERN-TH-2017-003https://cds.cern.ch/record/22425372017003Standard Model with spontaneously broken quantum scale invariance
https://cds.cern.ch/record/2242536
We explore the possibility that scale symmetry is a quantum symmetry broken only spontaneously and apply this idea to the Standard Model (SM) potential. We analyze the quantum corrections to the potential of the higgs field ($\phi$) in the classically scale invariant version of the SM ($m_\phi=0$ at tree level) extended by the dilaton ($\sigma$). The one-loop scalar potential is scale invariant, since the loop calculations preserve the scale symmetry, with the subtraction scale generated spontaneously by the dilaton vev, $\langle\sigma\rangle$. The potential contains new, non-polynomial (scale-invariant) operators of quantum origin, beyond the usual Coleman-Weinberg term (itself made scale-invariant). The Callan-Symanzik equation of the potential is verified in the presence of the gauge, Yukawa and the non-polynomial operators whose coefficients have non-zero beta functions. At the quantum level the higgs mass is protected although the theory is non-renormalizable, while the vacuum energy vanishes, following quantum scale invariance of the potential. We compare the scale-invariant one-loop potential to its counterpart computed in the "usual" regularization that breaks scale symmetry explicitly, in the presence at the tree level of non-polynomial operators.Ghilencea, D.M.Lalak, Z.Olszewski, P.Fri, 20 Jan 2017 06:22:45 GMT2016-12-29CERN-TH-2016-242https://cds.cern.ch/record/22425362016242Highly-sensitive superconducting circuits at ~700 kHz with tunable quality factors for image-current detection of single trapped antiprotons
https://cds.cern.ch/record/2242535
We developed highly-sensitive image-current detection systems based on superconducting toroidal coils and ultra-low noise amplifiers for non-destructive measurements of the axial frequencies (550$\sim$800$\,$kHz) of single antiprotons stored in a cryogenic multi-Penning-trap system. The unloaded superconducting tuned circuits show quality factors of up to 500$\,$000, which corresponds to a factor of 10 improvement compared to our previously used solenoidal designs. Connected to ultra-low noise amplifiers and the trap system, signal-to-noise-ratios of 30$\,$dB at quality factors of > 20$\,$000 are achieved. In addition, we have developed a superconducting switch which allows continuous tuning of the detector's quality factor, and to sensitively tune the particle-detector interaction. This allowed us to improve frequency resolution at constant averaging time, which is crucial for single antiproton spin-transition spectroscopy experiments, as well as improved measurements of the proton-to-antiproton charge-to-mass ratio. We developed highly sensitive image-current detection systems based on superconducting toroidal coils and ultra-low noise amplifiers for non-destructive measurements of the axial frequencies (550–800 kHz) of single antiprotons stored in a cryogenic multi-Penning-trap system. The unloaded superconducting tuned circuits show quality factors of up to 500 000, which corresponds to a factor of 10 improvement compared to our previously used solenoidal designs. Connected to ultra-low noise amplifiers and the trap system, signal-to-noise-ratios of 30 dB at quality factors of >20 000 are achieved. In addition, we have developed a superconducting switch which allows continuous tuning of the detector’s quality factor and to sensitively tune the particle-detector interaction. This allowed us to improve frequency resolution at constant averaging time, which is crucial for single antiproton spin-transition spectroscopy experiments, as well as improved measurements of the proton-to-antiproton charge-to-mass ratio.Nagahama, H.Schneider, G.Mooser, A.Smorra, C.Sellner, S.Harrington, J.Higuchi, T.Borchert, M.Tanaka, T.Besirli, M.Blaum, K.Matsuda, Y.Ospelkaus, C.Quint, W.Walz, J.Yamazaki, Y.Ulmer, S.Fri, 20 Jan 2017 06:22:43 GMT2016-12-26arXiv:1612.08481https://cds.cern.ch/record/2242535['arXiv:1612.08481']arXiv:1612.08481Dark Matter's secret liaisons: phenomenology of a dark $U(1)$ sector with bound states
https://cds.cern.ch/record/2242534
Dark matter (DM) charged under a dark U(1) force appears in many extensions of the Standard Model, and has been invoked to explain anomalies in cosmic-ray data, as well as a self-interacting DM candidate. In this paper, we perform a comprehensive phenomenological analysis of such a model, assuming that the DM abundance arises from the thermal freeze-out of the dark interactions. We include, for the first time, bound-state effects both in the DM production and in the indirect detection signals, and quantify their importance for Fermi, AMS, and CMB experiments. We find that DM in the mass range 1 GeV to 100 TeV, annihilating into dark photons of MeV to GeV mass, is in conflict with observations. Instead, DM annihilation into heavier dark photons is viable. We point out that the late decays of multi-GeV dark photons can produce significant entropy and thus dilute the DM density. This can lower considerably the dark coupling needed to obtain the DM abundance, and in turn relax the existing constraints.Cirelli, MarcoPanci, PaoloPetraki, KalliopiSala, FilippoTaoso, MarcoFri, 20 Jan 2017 06:22:34 GMT2016-12-21CERN-TH-2016-255https://cds.cern.ch/record/22425342016255Dark Matter "Collider" from Inelastic Boosted Dark Matter
https://cds.cern.ch/record/2242533
We propose a novel dark matter (DM) detection strategy for the models with non-minimal dark sector. The main ingredients in the underlying DM scenario are a boosted DM particle and a heavier dark sector state. The relativistic DM impinged on target material scatters off inelastically to the heavier state which subsequently decays into DM along with lighter states including visible (Standard Model) particles. The expected signal event, therefore, accompanies a visible signature by the secondary cascade process associated with a recoiling of the target particle, differing from the typical neutrino signal not involving the secondary signature. We then discuss various kinematic features followed by DM detection prospects at large volume neutrino detectors with a model framework where a dark gauge boson is the mediator between the Standard Model particles and DM.Kim, DoojinPark, Jong-ChulShin, SeodongFri, 20 Jan 2017 06:22:30 GMT2016-12-20CERN-TH-2016-258https://cds.cern.ch/record/22425332016258The complete NLO corrections to dijet hadroproduction
https://cds.cern.ch/record/2242532
We study the production of jets in hadronic collisions, by computing all contributions proportional to $\alpha_S^n\alpha^m$, with $n+m=2$ and $n+m=3$. These correspond to leading and next-to-leading order results, respectively, for single-inclusive and dijet observables in a perturbative expansion that includes both QCD and electroweak effects. We discuss issues relevant to the definition of hadronic jets in the context of electroweak corrections, and present sample phenomenological predictions for the 13-TeV LHC. We find that both the leading and next-to-leading order contributions largely respect the relative hierarchy established by the respective coupling-constant combinations.Frederix, RikkertFrixione, StefanoHirschi, ValentinPagani, DavideShao, Hua-ShengZaro, MarcoFri, 20 Jan 2017 06:22:25 GMT2016-12-20CERN-TH-2016-250https://cds.cern.ch/record/22425322016250Ultra-Light Dark Matter Resonates with Binary Pulsars
https://cds.cern.ch/record/2242531
We consider the scenario where dark matter (DM) is represented by an ultra-light classical scalar field performing coherent periodic oscillations. We point out that such DM perturbs the dynamics of binary systems either through its gravitational field or via direct coupling to ordinary matter. This perturbation gets resonantly amplified if the frequency of DM oscillations is close to a (half-)integer multiple of the orbital frequency of the system and leads to a secular variation of the orbital period. We suggest to use binary pulsars as probes of this scenario and estimate their sensitivity. While the current accuracy of observations is not yet sufficient to probe the purely gravitational effect of DM, it already yields constraints on direct coupling that are competitive with other bounds. The sensitivity will increase with the upcoming radio observatories such as Square Kilometer Array.Blas, DiegoNacir, Diana LopezSibiryakov, SergeyFri, 20 Jan 2017 06:22:24 GMT2016-12-20CERN-TH-2016-257https://cds.cern.ch/record/22425312016257Non-gaussianity of the critical 3d Ising model
https://cds.cern.ch/record/2242530
We discuss the 4pt function of the critical 3d Ising model, extracted from recent conformal bootstrap results. We focus on the non-gaussianity Q - the ratio of the 4pt function to its gaussian part given by three Wick contractions. This ratio reveals significant non-gaussianity of the critical fluctuations. The bootstrap results are consistent with a rigorous inequality due to Lebowitz and Aizenman, which limits Q to lie between 1/3 and 1.Rychkov, SlavaSimmons-Duffin, DavidZan, BernardoFri, 20 Jan 2017 06:22:22 GMT2016-12-07arXiv:1612.02436https://cds.cern.ch/record/2242530['arXiv:1612.02436']arXiv:1612.02436