The top quark is the heaviest elementary particle in the Standard Model, and has an
expected Yukawa coupling of order unity. The value of this coupling is a key ingredient to unravel the nature of the observed Higgs boson. The only known process which has a direct sensitivity to this coupling is the production of a Higgs boson in association with a top quark-pair ($t\bar{t}H$). This talk will...
This presentation shows the observation of the decay of the Higgs bosons to b quark-antiquark pairs by the ATLAS experiment. The analysis presented includes datasets recorded in LHC Run-1 and Run-2. ttH, VBF and VH production modes analyzed to extract the signals are discussed.
FCC-hh is a proposed future energy-frontier hadron collider, which goal is to provide high luminosity proton-proton collisions at a centre-of-mass energy of 100 TeV. The FCC-hh has an extremely rich physics program ranging from standard model (SM) measurements to direct searches for physics beyond the standard model (BSM). Among processes sensitive to new physics are Flavour-Changing Neutral...
Many supersymmetric scenarios feature final states with non-standard final state objects. The production of massive sparticles can lead to the production of boosted top quarks or vector bosons, high-pt b-jets. At the same time, transitions between nearly mass-degenerate sparticles can challenge the standard reconstruction because of the presence of very soft leptons or jets. The talk will...
The multiplicities of light (anti)nuclei were measured recently by the ALICE collaboration in Pb+Pb collisions at the center-of-mass collision energy $\sqrt{s} =2.76$ TeV [1]. Surprisingly, the hadron resonance gas model (HRGM) is able to perfectly describe the their multiplicities [2] under various assumptions. For instance, one can consider the (anti)nuclei with a vanishing hard-core radius...
Machine learning methods are widely used in the LHCb experiment at every stage of data processing. This talk will cover some of the established applications of machine learning, such as the classification and selection of interesting events in triggering and offline analysis of the data, such as particle identification, unbiased offline characterization of reconstructed events, tracking, and...
In the Standard Model the three charged leptons are identical copies of each other, apart from mass differences, and the electroweak coupling of the gauge bosons to leptons is independent of the lepton flavour. This prediction is called lepton flavour universality (LFU) and is well tested in tree level decays; any violation of LFU would be a clear sign of physics beyond the Standard Model....
Precision measurements of CP violating observables in hadron decays are powerful probes to search for physics effects beyond the Standard Model.
The most recent results on CP violation in decays of mesons and baryons obtained by
the LHCb Collaboration will be presented, some of which are world-first measurements.
In particular results obtained exploiting the data collected during the Run 2 of...
Motivated by recent V.A. Nikitin's reports on observation of 9-MeV$/c^2$
charged particles with a 2 meter JINR propane bubble chamber we perform an
experiment at the LPI electron synchrotron "Pakhra" with the aim to detect
such particles in the Bethe--Heitler process. Theoretical limits for masses
of new light charged particles of spin 0, 1/2 and 1 arising from precise
data on the muon...
The decay K+→π+νν, with a very precisely predicted branching ratio of less than 10-10, is one of the best candidates to reveal indirect effects of new physics at the highest mass scales. The NA62 experiment at CERN SPS is designed to measure the branching ratio of the K+→π+νν with a decay-in-flight technique, novel for this channel. NA62 took data in 2016, 2017 and another year run is...
Tau neutrino properties are not so well known in comparison to those of muon or electron neutrinos. The tau neutrino interaction cross-section was only measured by the DONUT experiment in 2008 with a large systematical error of 50% due to a poor knowledge of the tau neutrino flux in this beam dump experiment. However, the better measurement of this cross section is needed for the planned ...
According to some theoretical models a new dark matter gauge boson A' (dark photon) might exist, possibly coupled with ordinary photon by different(non-gravitational) type of weak interaction. The NA64 experiment at CERN SPS accelerator is aimed at probing an unexplored parameter space of kinetic gamma-A' mixing strength and mass values of A'. Experiment utilizes 100 GeV electron beam and the...
Search for parameter modification of neutral light mesons in nuclear matter in Hyperon-M experiment at U-70 accelerator
Sergey Evdokimov et al. (Hyperon-M experiment)
Hyperon-M at U-70 accelerator in Protvino is fixed-target experiment for study of parameter modifications of neutral light
mesons produced in meson-nucleus interactions on different nuclear targets. On the base of collected...
Abstract. M.Yu. Bogolyubsky, A.A. Volkov, D.K. Elumakhov, A.A. Ivanilov, A.Yu. Kalinin, A.N. Krinitsyn, V.I. Kryshkin, N.V. Kulagin, D.I. Patalakha, K.A. Romanishin, V.V. Skvortsov, V.V. Talov, L.K. Turchanovich
“Comparisom of the Measured Invarinat Cross Sections with Model Predictions for Production at Zero Angle of Secondary Light nuclei in CC-collisions at Beam Energy 20.5 GeV/n on...
A.A. Bogdanov1, V.A.Chetvertkova4, V.P. Ladygin3, V.V.Mochalov1,2, M.B. Nurusheva1, V.A. Okorokov1, P.A.Semenov,1,2, A.N.Vasiliev1,2,
L.S.Zherebtsova1,2
- National Research Nuclear University (Moscow Engineering Physics Institute), Moscow, 115409, Russia
- NRC «Kurchatov Institute» - IHEP, Protvino, Moscow region, 142281, Russia
- Joint Institute for Nuclear Research, Dubna, Moscow...
The asymmetry of baryon/antibaryon production has been measured in many proton-proton, pion-proton and electron-proton experiments. In the framework of Quark-Gluon String Model the energy dependence of asymmetry tells us about the value of \alpha_{SJ}(0), the intercept of String Junction Regge trajectory. This object (SJ) transfers the baryon charge from proton projectile into the central...
Recent results from the Belle experiment.
B.Shwartz for Belle collaboration,
Budker Institute of Nuclear Physics and Novosibirsk State University,
Novosibisrsk, Russia
Experiments at the KEKB ee energy-asymmetric collider with world highest luminosity, 2.11034cm-2s-1, continued with the Belle detector from 1999 to 2010. The total integrated luminosity collected in these experiments in the...
The talk will cover most recent results and present status of the spectroscopy of excited heavy (charmed and bottom) baryons: their masses, natural widths, decay modes and presumably assigned quantum numbers.
A review of recent charmonium experimental results at Belle is presented, including observation of an alternative $\chi_{c0}(2P)$ candidate in $e^+ e^- \rightarrow J/\psi D \bar{D}$, measurements of the absolute branching fractions of $B^+ \rightarrow X_{c\bar{c}} K^+$, measurement of $\eta_c(1S)$ and $\eta_c(2S)$ two-photon production, search for $\Upsilon(1S,2S) \to Z_c^+ \bar{Z}_c^-$.
Until recently, parameters of vector charmoinia lying above the open-charm threshold were determined from the inclusive cross section of the electron-positron annihilation to hadronic final state. However, the parameters of the resonances obtained this way are model-dependent and they suffer from large uncertainties. On the other hand, measurements of exclusive cross sections of the e+e-...
Line shapes of the Zb(10610) and Zb(10650) bottomonium-like exotic states produced in the decays of vector bottomonium Upsilon(10860) are analysed. A combined analysis of the existing experimental data in the elastic and inelastic decay channels of Upsilon(10860) is performed within a nonperturbative coupled-channel approach which complies with the requirements of unitarity and analyticity of...
Assuming a molecular nature for the $Z_b(10610)$ and $Z_b(10650)$ exotic states, the properties of these states and their pole positions are extracted from the effective-field theory based analysis of the experimental line shapes in the decay channels $\Upsilon(10860) \to \pi \alpha$ (with $\alpha$ being $B\bar B^*, B^*\bar B^*$ and $h_b (mP)\pi$ ($m$=1,2)). The consequences for the...
In this talk we review recent results on heavy flavor physics at ATLAS and CMS. It includes results from a study of production and properties of b-hadrons with open or hidden beauty as well as rare decays of B-mesons in which the phenomena of New Physics were searched for.
The discussed results are based on the statistics obtained
during Run I (8 TeV) and Run II (13 TeV).
The Belle II detector together with the SuperKEKB e+e− asymmetric collider are the second generation experiment at a B-Factory. The aim is to reach a luminosity of 8 × 1035 cm$^{−2}$s$^{−1}$, that is a Υ(4S) production rate close to 800 Hz, by exploiting the nano beam collision scheme with large Piwinsky angle.
A major upgrade of all the components of the former Belle detector had been...
The observation of the Bs2(5840)0 -> B0 K0S decay and the evidence for the Bs1(5830)0 -> B0 K0S decay are presented. The analysis uses the data collected by the CMS experiment at the LHC in proton-proton collisions at sqrt(s) = 8 TeV. In addition, properties of the P-wave B0 s mesons are determined, as well as the mass differences MB0 − MB+ and MB0 - MB*+, where the latter is measured for...
The last year was marked by the first observation of doubly heavy baryon $\Xi_{cc}^{++}$ in the decay mode $\Lambda_c^+ K^- \pi^+ \pi^+$, which was confirmed by the observation of decay $\Xi_{cc}^{++} \to \Xi_c^+ \pi^+$ this year. This circumstance greatly revived the research activities in this direction. In the study we discuss from the theoretical point of view the perspectives of...
The newly observed $d^*(2380)$ resonance ($I(J^P)=0(3^+)$) is studied based on a chiral constituent quark model. Its overall properties, including the mass, the partial decay widths in various decay modes, and the total width, are well reproduced in our calculation and with a compact scenario. Our results show that a compact hexaquark dominated structure might be a reasonable interpretation...
In view of the recent discovery of $\Xi_{cc}$ by the LHCb collaboration the study of doubly heavy baryons is becoming relevant. In this work we discuss the prospects of the observation of such states with excited $cc$-diquark (S and P excitations) by the LHCb experiment. P-wave excitations of a diquark in $\Xi_{cc}$ are expected to be quite narrow since their decay into the ground state is...
The Dibarion resonance d(2380) was measured in the two pion production
reactons $pN->d\pi\pi$ and by use of a polarized
deuteron beam in the quasifree scattering mode on hydrogen target.
Total and differential cross sections have been measured for the various isotopic
final states. Covered energy region includes the regions of N(1440) and
$\Delta(1230)\Delta(1230)$ resonance excitations....
