High Energy Physics  Experiment
New submissions
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New submissions for Fri, 23 Aug 19
 [1] arXiv:1908.08215 [pdf, other]

Title: Search for electroweak production of charginos and sleptons decaying into final states with two leptons and missing transverse momentum in $\sqrt{s}=13$ TeV $pp$ collisions using the ATLAS detectorAuthors: ATLAS CollaborationComments: 30 pages plus author list + cover pages (47 pages total), 8 figures, 9 tables, submitted to EPJ C, All figures including auxiliary figures are available at this https URLSubjects: High Energy Physics  Experiment (hepex)
A search for the electroweak production of charginos and sleptons decaying into final states with two electrons or muons is presented. The analysis is based on 139 fb$^{1}$ of protonproton collisions recorded by the ATLAS detector at the Large Hadron Collider at $\sqrt{s}=13$ TeV. Three $R$parityconserving scenarios where the lightest neutralino is the lightest supersymmetric particle are considered: the production of chargino pairs with decays via either $W$ bosons or sleptons, and the direct production of slepton pairs. The analysis is optimised for the first of these scenarios, but the results are also interpreted in the others. No significant deviations from the Standard Model expectations are observed and limits at 95 % confidence level are set on the masses of relevant supersymmetric particles in each of the scenarios. For a massless lightest neutralino, masses up to 420 GeV are excluded for the production of the lightestchargino pairs assuming $W$bosonmediated decays and up to 1 TeV for sleptonmediated decays, whereas for sleptonpair production, masses up to 700 GeV are excluded assuming three generations of massdegenerate sleptons.
 [2] arXiv:1908.08461 [pdf, other]

Title: Search for flavourchanging neutral currents in processes with one top quark and a photon using 81 fb$^{1}$ of $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS experimentAuthors: ATLAS CollaborationComments: 34 pages in total, author list starting page 18, 2 figures, 1 table, submitted to Phys. Lett. B. All figures including auxiliary figures are available at this http URLSubjects: High Energy Physics  Experiment (hepex)
A search for flavourchanging neutral current (FCNC) events via the coupling of a top quark, a photon, and an up or charm quark is presented using 81 fb$^{1}$ of protonproton collision data taken at a centreofmass energy of 13 TeV with the ATLAS detector at the LHC. Events with a photon, an electron or muon, a $b$tagged jet, and missing transverse momentum are selected. A neural network based on kinematic variables differentiates between events from signal and background processes. The data are consistent with the backgroundonly hypothesis, and limits are set on the strength of the $tq\gamma$ coupling in an effective field theory. These are also interpreted as 95% CL upper limits on the cross section for FCNC $t\gamma$ production via a lefthanded (righthanded) $tu\gamma$ coupling of 36 fb (78 fb) and on the branching ratio for $t\rightarrow \gamma u$ of $2.8\times 10^{5}$ ($6.1\times 10^{5}$). In addition, they are interpreted as 95% CL upper limits on the cross section for FCNC $t\gamma$ production via a lefthanded (righthanded) $tc\gamma$ coupling of 40 fb (33 fb) and on the branching ratio for $t\rightarrow \gamma c$ of $22\times 10^{5}$ ($18\times 10^{5}$).
 [3] arXiv:1908.08500 [pdf, other]

Title: Search for supersymmetry using Higgs boson to diphoton decays at $\sqrt{s}$ = 13 TeVAuthors: CMS CollaborationComments: Submitted to JHEP. All figures and tables can be found at this http URL (CMS Public Pages)Subjects: High Energy Physics  Experiment (hepex)
A search for supersymmetry (SUSY) is presented where at least one Higgs boson is produced and decays to two photons in the decay chains of pairproduced SUSY particles. Two complementary analysis strategies are pursued: one focused on strong SUSY production and the other focused on electroweak SUSY production. The presence of charged leptons, additional Higgs boson candidates, and various kinematic variables are used to categorize events into search regions that are sensitive to different SUSY scenarios. The results are based on data from protonproton collisions at the Large Hadron Collider at a centerofmass energy of 13 TeV collected by the CMS experiment, corresponding to an integrated luminosity of 77.5 fb$^{1}$. No statistically significant excess of events is observed relative to the standard model expectations. We exclude bottom squark pair production for bottom squark masses below 530 GeV and a lightest SUSY particle mass of 1 GeV; winolike charginoneutralino production for chargino and neutralino masses below 235 GeV with a gravitino mass of 1 GeV; and higgsinolike charginoneutralino production in the case where the neutralino decays exclusively to a Higgs boson and a gravitino for neutralino masses below 290 GeV.
Crosslists for Fri, 23 Aug 19
 [4] arXiv:1908.08166 (crosslist from nuclex) [pdf, other]

Title: Nuclear Isotope Production by Ordinary Muon Capture ReactionAuthors: I.H. Hashim, H. Ejiri, F. Othman, F. Ibrahim, F. Soberi, N.N.A.M.A. Ghani, T. Shima, A. Sato, K. NinomiyaComments: 21 pages, 5 figuresSubjects: Nuclear Experiment (nuclex); High Energy Physics  Experiment (hepex); Instrumentation and Detectors (physics.insdet)
Muon capture isotope production (MuCIP) using negative ordinary muon capture reactions (OMC) is used to efficiently produce various kinds of nuclear isotopes for both fundamental and applied science studies. The large capture probability of muon into a nucleus, together with the high intensity muon beam, make it possible to produce nuclear isotopes in the order of 10^{910} per second depending on the muon beam intensity. Radioactive isotopes (RIs) produced by MuCIP are complementary to those produced by photon and neutron capture reactions and are used for various science and technology applications. MuCIP on ^{Nat}Mo by using the RCNP MuSIC \muon beam is presented to demonstrate the feasibility of MuCIP. Nuclear isotopes produced by MuCIP are evaluated by using a preequilibrium (PEQ) and equilibrium (EQ) proton neutron emission model. Radioactive $^{99}$Mo isotopes and the metastable ^{99m}Tc isotopes, which are used extensively in medical science, are produced by MuCIP on ^{Nat}Mo and ^{100}Mo.
 [5] arXiv:1908.08212 (crosslist from physics.accph) [pdf, other]

Title: Operation of ILC250 at the ZpoleSubjects: Accelerator Physics (physics.accph); High Energy Physics  Experiment (hepex)
ILC (International Linear Collider) has been under consideration as the next global project of particle physics. It's Technical Design Report, published in 2013, described the accelerator for the centerofmass energy above 200GeV. Operation of ILC at lower centerofmass energy has not been studies intensively. This report discusses about the ILC for the centerofmass energy 91.2GeV and presents a possible parameter set.
 [6] arXiv:1908.08302 (crosslist from nuclth) [pdf, other]

Title: Firstforbidden transitions in the reactor anomalySubjects: Nuclear Theory (nuclth); High Energy Physics  Experiment (hepex); Nuclear Experiment (nuclex)
We describe here microscopic calculations performed on the dominant forbidden transitions in reactor antineutrino spectra above 4 MeV using the nuclear shell model. By taking into account Coulomb corrections in the most complete way, we calculate the shape factor with the highest fidelity and show strong deviations from allowed approximations and previously published results. Despite small differences in the ab initio electron cumulative spectra, large differences on the order of several percents are found in the antineutrino spectra. Based on the behaviour of the numerically calculated shape factors we propose a parametrization of forbidden spectra. Using Monte Carlo techniques we derive an estimated spectral correction and uncertainty due to forbidden transitions. We establish the dominance and importance of forbidden transitions in both the reactor anomaly and spectral shoulder analysis. Based on these results, we conclude that a correct treatment of forbidden transitions is indispensable in both the normalization anomaly and spectral shoulder.
 [7] arXiv:1908.08353 (crosslist from hepph) [pdf, other]

Title: CIMBA: fast Monte Carlo generation using cubic interpolationAuthors: Philip IltenComments: 16 pages, 6 figuresSubjects: High Energy Physics  Phenomenology (hepph); High Energy Physics  Experiment (hepex)
Monte Carlo generation of high energy particle collisions is a critical tool for both theoretical and experimental particle physics, connecting perturbative calculations to phenomenological models, and theory predictions to full detector simulation. The generation of minimum bias events can be particularly computationally expensive, where nonperturbative effects play an important role and specific processes and fiducial regions can no longer be well defined. In particular scenarios, particle guns can be used to quickly sample kinematics for single particles produced in minimum bias events. CIMBA (Cubic Interpolation for Minimum Bias Approximation) provides a comprehensive package to smoothly sample predefined kinematic grids, from any general purpose Monte Carlo generator, for all particles produced in minimum bias events. These grids are provided for a number of beam configurations including those of the Large Hadron Collider.
 [8] arXiv:1908.08355 (crosslist from hepph) [pdf, other]

Title: Towards the meV limit of the effective neutrino mass in neutrinoless doublebeta decaysAuthors: Jun Cao, Guoyuan Huang, YuFeng Li, Yifang Wang, LiangJian Wen, Zhizhong Xing, Zhenhua Zhao, Shun ZhouComments: 16 pages, 6 figuresSubjects: High Energy Physics  Phenomenology (hepph); High Energy Physics  Experiment (hepex)
In this paper, we emphasize why it is important for future neutrinoless doublebeta ($0\nu\beta\beta$) decay experiments to reach the sensitivity to the effective neutrino mass $m^{}_{\beta\beta} \approx 1~{\rm meV}$. Assuming such a sensitivity and the precisions on neutrino oscillation parameters after the JUNO experiment, we fully explore the constrained regions of the lightest neutrino mass $m^{}_1$ and two Majoranatype CPviolating phases $\{\rho, \sigma\}$. The implications for the neutrino mass spectrum, the effective neutrino mass $m^{}_\beta$ in beta decays and the sum of three neutrino masses $\Sigma \equiv m^{}_1 + m^{}_2 + m^{}_3$ relevant for cosmological observations are also discussed.
 [9] arXiv:1908.08490 (crosslist from nuclex) [pdf, other]

Title: Constraining the Sea Quark Distributions Through W$^\pm$ Cross Section Ratio Measurements at STARAuthors: M. Posik (for the STAR Collaboration)Comments: Submitted to DIS 2019 Proceedings. 6 pgs. 5 figSubjects: Nuclear Experiment (nuclex); High Energy Physics  Experiment (hepex)
Over the past several years, parton distribution functions (PDFs) have become more precise. However there are still kinematic regions where more data are needed to help constrain global PDF extractions, such as the ratio of the sea quark distributions $\bar{d}$/$\bar{u}$ near the valence region. Furthermore, current measurements appear to suggest different high$x$ behaviors of this ratio. The $W$ cross section ratio ($W^+$/$W^$) is sensitive to the unpolarized quark distributions at large $Q^2$ set by the $W$ mass. Such a measurement can be used to help constrain the $\bar{d}$/$\bar{u}$ ratio. The STAR experiment at RHIC is well equipped to measure the leptonic decays of $W$ bosons, in the midpseudorapdity range $\left(\eta \leq 1 \right)$, produced in protonproton collisions at $\sqrt{s}$ = 500/510 GeV. At these kinematics STAR is sensitive to quark distributions near $x$ of 0.16. STAR can also measure $W^+$/$W^$ in a more forward region ranging from 1.0 $< \eta <$1.5, which extends the sea quark sensitivity to higher $x$. RHIC runs from 2011 through 2013 have collected about 350 pb$^{1}$ of integrated luminosity, and an additional 350 pb$^{1}$ from the 2017 run. These proceedings will present preliminary results of the 20112013 $W^+$/$W^$ cross section ratio measurements. Additionally, the $W/Z$ cross section ratio, differential and total $W$ and $Z$ cross sections are presented.
 [10] arXiv:1908.08519 (crosslist from physics.dataan) [pdf, other]

Title: Unfolding as Quantum AnnealingComments: 8 pages, 5 figures, the source code is available at this https URLSubjects: Data Analysis, Statistics and Probability (physics.dataan); High Energy Physics  Experiment (hepex); Quantum Physics (quantph)
Highenergy physics is replete with hard computational problems and it is one of the areas where quantum computing could be used to speed up calculations. We present an implementation of likelihoodbased regularized unfolding on a quantum computer. The inverse problem is recast in terms of quadratic unconstrained binary optimization (QUBO), which has the same form of the Ising hamiltonian and hence it is solvable on a programmable quantum annealer. We tested the method using a model that captures the essence of the problem, and compared the results with a baseline method commonly used in precision measurements at the Large Hadron Collider (LHC) at CERN. The unfolded distribution is in very good agreement with the original one. We also show how the method can be extended to include the effect of nuisance parameters representing sources of systematic uncertainties affecting the measurement.
Replacements for Fri, 23 Aug 19
 [11] arXiv:1812.11931 (replaced) [pdf, ps, other]

Title: Probing the seesaw mechanism at the 250 GeV ILCComments: 8 pages, 4 figures, the version published in Phys. Lett. B (typos in Table III & IV have been corrected after the publication)Subjects: High Energy Physics  Phenomenology (hepph); High Energy Physics  Experiment (hepex)
 [12] arXiv:1903.05931 (replaced) [pdf, ps, other]

Title: Semileptonic decays of the scalar tetraquark $Z_{bc;\overline{u} \overline{d}}^{0}$Comments: 10 Pages and 3 FiguresSubjects: High Energy Physics  Phenomenology (hepph); High Energy Physics  Experiment (hepex); High Energy Physics  Lattice (heplat)
 [13] arXiv:1906.00489 (replaced) [pdf, other]

Title: Measurements of twoparticle correlations in $e^+e^$ collisions at 91 GeV with ALEPH archived dataAuthors: Anthony Badea, Austin Baty, Paoti Chang, Gian Michele Innocenti, Marcello Maggi, Christopher McGinn, Michael Peters, TzuAn Sheng, Jesse Thaler, YenJie LeeComments: Submitted to Phys. Rev. LettSubjects: High Energy Physics  Experiment (hepex)
 [14] arXiv:1906.02677 (replaced) [pdf, other]

Title: A First Look on 3D Effects in Open Axion HaloscopesAuthors: Stefan Knirck, Jan SchütteEngel, Alexander J. Millar, Javier Redondo, Olaf Reimann, Andreas Ringwald, Frank D. SteffenComments: 41 pages, 20 figures; typos corrected, references updatedJournalref: JCAP08(2019)026Subjects: Instrumentation and Detectors (physics.insdet); High Energy Physics  Experiment (hepex); High Energy Physics  Phenomenology (hepph)
 [15] arXiv:1907.03647 (replaced) [pdf, other]

Title: Phonon and light read out of a Li$_2$MoO$_4$ crystal with multiplexed kinetic inductance detectorsAuthors: N. Casali, L. Cardani, I. Colantoni, A. Cruciani, S. Di Domizio, M. Martinez, G. Pettinari, M. VignatiComments: 7 pages, 9 figuresSubjects: Instrumentation and Detectors (physics.insdet); High Energy Physics  Experiment (hepex); Nuclear Experiment (nuclex)
 [16] arXiv:1907.11193 (replaced) [pdf, other]

Title: Searches for Connections Between Dark Matter and Neutrinos with the IceCube HighEnergy Starting Event SampleComments: Presented at the 36th International Cosmic Ray Conference (ICRC 2019). See arXiv:1907.11699 for all IceCube contributions, 6 pages, 2 figuresSubjects: High Energy Physics  Phenomenology (hepph); High Energy Physics  Experiment (hepex)
 [17] arXiv:1908.07602 (replaced) [pdf, other]

Title: Quest for new physics using astrophysical neutrino flavor in IceCubeAuthors: Carlos A. Argüelles, Kareem Farrag, Teppei Katori, Shivesh Mandalia (for the IceCube Collaboration)Comments: Presented at the 36th International Cosmic Ray Conference (ICRC 2019). See arXiv:1907.11699 for all IceCube contributions. 8 Pages, 2 FiguresSubjects: High Energy Astrophysical Phenomena (astroph.HE); High Energy Physics  Experiment (hepex); High Energy Physics  Phenomenology (hepph)
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