Wed·Jun 6, 2018Wednesday·June 6, 2018

1. 01*

   Future perspectives for a weak mixing angle measurement in coherent elastic neutrino nucleus scattering experiments

   B. C. Cañas🇲🇽 · E. A. Garcés🇲🇽 · O. G. Miranda🇲🇽 · A. Parada🇨🇴

   After the first measurement of the coherent elastic neutrino nucleus scattering (CENNS) by the COHERENT Collaboration, it is expected that new experiments will confirm the observation. Such measurements will allow to put stronger constraints or discover new physics as well as to probe the Standard Model by measuring its parameters. This is the case of the weak mixing angle at low energies, which could be measured with an increased precision in future results of CENNS experiments using, for example, reactor antineutrinos. In this work we analyze the physics potential of different proposals for the improvement of our current knowledge of this observable and show that they are very promising.

   hep-phhep-exPLB(2018)·95 citations
2. 02*

   Probing Heavy Charged Higgs Boson at the LHC

   Monoranjan Guchait🇮🇳 · Aravind H. Vijay🇮🇳

   Signature of heavier charged Higgs boson, much above the top quark mass, is investigated at the LHC Run 2 experiments, following its decay mode via top and bottom quark focusing on both hadronic and leptonic signal final states. The generic two Higgs doublet model framework is considered with a special emphasis on supersymmetry motivated Type II model. The signal is found to heavily affected by the huge irreducible backgrounds due to the top pair production and QCD events. The jet substructure technique is used to tag moderately boosted top jets in order to reconstruct charged Higgs mass. The simple cut based analysis is performed optimizing various kinematic selections, and the signal sensitivity is found to be reasonable for only lower range of charged Higgs masses for very high luminosity 3000 fb${}^{-1}$ option. However, employing the multi-variate analysis(MVA) technique, a remarkable improvement in signal sensitivity is achieved. We find, the charged Higgs signal for the mass range about $300-600$ is observable with 1000 fb${}^{-1}$ luminosity option. However, for more high luminosity option 3000 fb${}^{-1}$, the discovery potential can be extended to $700-800$ GeV.

   hep-phhep-exPRD(2018)·18 citations
3. 03*

   Contributions to $b\to s\ell \ell$ Anomalies from $R$-Parity Violating Interactions

   Kevin Earl🇨🇦 · Thomas Gregoire🇨🇦

   We examine the parameter space of supersymmetric models with $R$-parity violating interactions of the form ${\lambda }^{\prime }LQ{D}^c$ to explain the various anomalies observed in $b\to s\ell \ell$ transitions. To generate the appropriate operator in the low energy theory, we are led to a region of parameter space where loop contributions dominate. In particular, we concentrate on parameters for which diagrams involving winos, which have not been previously considered, give large contributions. Many different potentially constraining processes are analyzed, including $\tau \to \mu \mu \mu$, $B_s-{\bar{B}}_s$ mixing, $B\to K^{(\ast )}\nu \bar{\nu }$, $Z$ decays to charged leptons, and direct LHC searches. We find that it is possible to explain the anomalies, but it requires large values of ${\lambda }^{\prime }$, which lead to relatively low Landau poles.

   hep-phJHEP(2018)·40 citations
4. 04*

   Top quark decays with flavor violation in the B-LSSM

   Jin-Lei Yang🇨🇳 · Tai-Fu Feng🇨🇳 · Hai-Bin Zhang🇨🇳 · Guo-Zhu Ning🇨🇳 · Xiu-Yi Yang🇨🇳

   The decays of top quark $t\to c\gamma ,t\to cg,t\to cZ,t\to ch$ are extremely rare processes in the standard model (SM). The predictions on the corresponding branching ratios in the SM are too small to be detected in the future, hence any measurable signal for the processes at the LHC is a smoking gun for new physics. In the extension of minimal supersymmetric standard model with an additional local $U(1{)}_{B-L}$ gauge symmetry (B-LSSM), new gauge interaction and new flavor changing interaction affect the theoretical evaluations on corresponding branching ratios of those processes. In this work, we analyze those processes in the B-LSSM, under a minimal flavor violating assumption for the soft breaking terms. Considering the constraints from updated experimental data, the numerical results imply $Br(t\to c\gamma )\sim 5\times 10^{-7}$, $Br(t\to cg)\sim 2\times 10^{-6}$, $Br(t\to cZ)\sim 4\times 10^{-7}$ and $Br(t\to ch)\sim 3\times 10^{-9}$ in our chosen parameter space. Simultaneously, new gauge coupling constants $g_{{}_B},g_{{}_{YB}}$ in the B-LSSM can also affect the numerical results of $Br(t\to c\gamma ,cg,cZ,ch)$.

   hep-phEPJC(2018)·27 citations
5. 05*

   Toward simulation of quark and diquark fragmentations in the Quark-Gluon String Model (QGSM)

   V. Uzhinsky🇷🇺 · A. Galoyan🇷🇺

   Within the Quark-Gluon String Model A.B. Kaidalov found a behaviour of quark and diquark fragmentation functions for $z\to 0$ and $z\to 1$, and proposed interpolation formulae for the functions in the whole region of $z$. These functions must be a solution of the well-known system of the integral equations. A simplified Monte Carlo estimation of the functions, based on usage of the fragmentation functions at $z\to 1$ as the kernel functions of the system, does not reproduce Kaidalov's results. An improvement of the Monte Carlo simulations is proposed in this paper. It can be implemented in Monte Carlo event generators such as Los Alamos QGSM, QGSJet-II and the Geant4 QGS model. It will improve a description of experimental data in the models, especially, the description of the latest NA61/SHINE Collaboration data on $\pi \mathrm{C}$ interactions. Description of the data is a problem in DPMJet, QGSJet, EPOS and Sibyll models.

   hep-phhep-exnucl-exPhys.Part.Nucl.Lett.(2019)·1 citation
6. 06*

   Transverse-momentum resummation fo top-quark pair production at the LHC

   Stefano Catani🇮🇹 · Massimiliano Grazzini🇨🇭 · Hayk Sargsyan🇨🇭

   We consider transverse-momentum resummation for top-quark pair production in hadron collisions. At small transverse momenta of the top-quark pair, the logarithmically-enhanced QCD contributions are resummed to all orders up to next-to-leading logarithmic accuracy. At intermediate and large values of transverse momenta, the resummation is consistently combined with the complete result at fixed perturbative order. We present numerical results for the transverse-momentum distribution of top-quark pairs at LHC energies. We perform a detailed study of the scale dependence of the results to estimate their perturbative uncertainty. We comment on the comparison with ATLAS and CMS data.

   hep-phhep-exJHEP(2018)·39 citations
7. 07*

   Interpretation of the newly discovered $\Omega$(2012)

   T. M. Aliev🇹🇷 · K. Azizi🇹🇷 · Y. Sarac🇹🇷 · H. Sundu🇹🇷

   Very recently Belle Collaboration reported observation of a narrow state called $\Omega (2012)$ with mass $2012.4\pm 0.7$~(stat)~$\pm 0.6$(syst)~MeV and width $6.4_{-2.0}^{+2.5}$~(stat)~$\pm 1.6$~(syst)~MeV. We calculate the mass and residue of $\Omega (2012)$ state by employing the QCD sum rule method. Comparison of the obtained results with the experimental data allows us to interpret this state as $1P$ orbital excitation of the ground state $\Omega$ baryon, i.e. with quantum numbers $J^P={\frac{3}{2}}^{-}$.

   hep-phhep-exhep-latPRD(2018)·42 citations
8. 08*

   Two-photon exchange correction in elastic lepton-proton scattering

   Oleksandr Tomalak🇩🇪

   We present the dispersion relation approach based on unitarity and analyticity to evaluate the two-photon exchange contribution to elastic electron-proton scattering. The leading elastic and first inelastic $\pi N$ intermediate state contributions are accounted for in the region of small momentum transfer $Q^2<1{\mathrm{GeV}}^2$ based on the available data input. The novel methods of analytical continuation allow us to exploit the MAMI form factor data and the MAID parameterization for the pion electroproduction amplitudes as input in the calculation. The results are compared to the recent CLAS, VEPP-3 and OLYMPUS data as well as to the full two-photon exchange correction in the near-forward approximation, which is based on the Christy and Bosted unpolarized structure functions fit. Additionally, predictions are given for a forthcoming muon-proton scattering experiment.

   hep-phnucl-exnucl-thFew Body Syst.(2018)·15 citations
9. 09*

   Preface to the 20th workshop "What comes beyond the standard models", Bled July 09--17, 2017, and links to the talks appearing in the proceedings, and/or in arXiv

   N. S. Mankoč Borštnik🇸🇮 · H. F. B. Nielsen🇩🇰 · M. Y. Khlopov🇷🇺 · D. Lukman🇸🇮

   The contribution contains the preface to the Proceedings to the 20th Workshop "What Comes Beyond the Standard Models", Bled, July 09 - 17, 2017, published in Bled workshops in physics, Vol.18, No. 2, DMFA-Založnistvo, Ljubljana, Dec. 2017, links to (most of) the published contributions and section (by M.Yu. Khlopov) on VIA at Bled 2017.

   hep-phgr-qchep-thmath-ph+12 citations
10. 10*

    Consistent Relativistic Chiral Kinetic Theory: a derivation from OSEFT

    Stefano Carignano🇪🇸 · Cristina Manuel🇪🇸 · Juan M. Torres-Rincon🇺🇸

    We formulate the on-shell effective field theory (OSEFT) in an arbitrary frame and study its reparametrization invariance (RI), which ensures that it is respectful of Lorentz symmetry. In this formulation the OSEFT Lagrangian looks formally equivalent to the sum over light-like velocities of soft collinear effective field theory in the Abelian limit, differences remain in the scale of the gauge fields involved in the two effective theories. We then use the OSEFT Lagrangian expanded in powers of the on-shell energy to derive how the classical transport equations for charged massless fermions are corrected by quantum effects, as derived from quantum field theory. We provide a formulation in a full covariant way, and explain how the consistent form of the chiral anomaly equation can be recovered from our results. We also show how the side jump transformation of the distribution function associated with massless charged fermions can be derived from the RI transformation rules of the OSEFT quantum fields. Finally, we discuss differences in our results with others found in the literature.

    hep-phPRD(2018)·54 citations
11. 11*

    Factorized groomed jet mass distribution in inclusive jet processes

    Junegone Chay🇰🇷 · Chul Kim🇰🇷

    We consider the factorized groomed jet mass distribution in inclusive jet processes using modified mass drop tagger (mMDT), corresponding to soft drop with the angular exponent $\beta =0$. A grooming procedure is implemented rather than tagging in the sense that grooming always returns a groomed jet, while tagging dose not return a jet when a single particle remains after tagging. We find that the grooming procedure makes the jet mass distribution infrared safe and only ultraviolet divergences appear in each factorized part. The groomed jet mass distributions are investigated in a wide range of the jet mass considering various limits on the jet mass variable $\rho =M_J^2/(p_T^{J}R{)}^2$ and the grooming cut $y_c$. Appropriate effective theories in different kinematic regions are employed to resum large logarithms, in which the analysis in the region $\rho \sim y_c\ll 1$ is included due to the different type of factorization. The analytic computation of the factorized groomed jet mass distribution is presented by resumming the large logarithms in the jet mass, and $y_c$. Numerically, the effect of the resummation is notably enhanced, compared with the calculation at next-to-leading order, and nonglobal logarithms are estimated to be small.

    hep-phJ.Korean Phys.Soc.(2019)·9 citations
12. 12*

    An inverse seesaw model with $U(1{)}_R$ gauge symmetry

    Takaaki Nomura🇰🇷 · Hiroshi Okada🇰🇷

    We propose a natural realization of inverse seesaw model with right-handed and flavor dependent $U(1)$ gauge symmetries, in which we formulate the neutrino mass matrix to reproduce current neutrino oscillation data in a general way. Also we study a possibility to provide predictions to the neutrino sector by imposing an additional flavor dependent $U(1{)}_{L_{\mu }-L_{\tau }}$ gauge symmetry that also satisfies the gauge anomaly cancellation conditions associated with $U(1{)}_R$. Then we analyze collider physics on a extra gauge boson and show a possibility of detection.

    hep-phLHEP(2018)·13 citations
13. 13*

    Exploring High Multiplicity Amplitudes in Quantum Mechanics

    Joerg Jaeckel🇩🇪 · Sebastian Schenk🇩🇪

    Calculations of $1\to N$ amplitudes in scalar field theories at very high multiplicities exhibit an extremely rapid growth with the number $N$ of final state particles. This either indicates an end of perturbative behaviour, or possibly even a breakdown of the theory itself. It has recently been proposed that in the Standard Model this could even lead to a solution of the hierarchy problem in the form of a "Higgsplosion". To shed light on this question we consider the quantum mechanical analogue of the scattering amplitude for $N$ particle production in ${\varphi }^4$ scalar quantum field theory, which corresponds to transitions $⟨N|\hat{x}|0⟩$ in the anharmonic oscillator with quartic coupling $\lambda$. We use recursion relations to calculate the $⟨N|\hat{x}|0⟩$ amplitudes to high order in perturbation theory. Using this we provide evidence that the amplitude can be written as $⟨N|\hat{x}|0⟩\sim \exp (F(\lambda N)/\lambda )$ in the limit of large $N$ and $\lambda N$ fixed. We go beyond the leading order and provide a systematic expansion in powers of $1/N$. We then resum the perturbative results and investigate the behaviour of the amplitude in the region where tree-level perturbation theory violates unitarity constraints. The resummed amplitudes are in line with unitarity as well as stronger constraints derived by Bachas. We generalize our result to arbitrary states and powers of local operators $⟨N|{\hat{x}}^q|M⟩$ and confirm that, to exponential accuracy, amplitudes in the large $N$ limit are independent of the explicit form of the local operator, i.e. in our case $q$.

    hep-phhep-thPRD(2018)·20 citations
14. 14*

    Prethermalization Production of Dark Matter

    Marcos A. G. Garcia🇺🇸 · Mustafa A. Amin🇺🇸

    At the end of inflation, the inflaton field decays into an initially nonthermal population of relativistic particles which eventually thermalize. We consider the production of dark matter from this relativistic plasma, focusing on the prethermal phase. We find that for a production cross section $\sigma (E)\sim E^n$ with $n>2$, the present dark matter abundance is produced during the prethermal phase of its progenitors. For $n\le 2$, entropy production during reheating makes the nonthermal contribution to the present dark matter abundance subdominant compared to that produced thermally. As specific examples, we verify that the nonthermal contribution is irrelevant for gravitino production in low scale supersymmetric models ($n=0$) and is dominant for gravitino production in high scale supersymmetry models ($n=6$).

    hep-phastro-ph.COPRD(2018)·111 citations
15. 15*

    Estimation of the freeze-out parameters reachable in the AFTER@LHC project

    Viktor Begun🇵🇱 · Daniel Kikoła🇵🇱 · Volodymyr Vovchenko🇩🇪 · Daniel Wielanek🇵🇱

    Estimation of the freeze-out parameters as the function of rapidity in Pb+Pb collisions at $\sqrt{s_{NN}}=72$ GeV in the AFTER@LHC project is performed. The conventional hadron resonance gas model is used for the analysis of the events generated by the UrQMD model. The results indicate that one may obtain at least $2.5$ times increase of baryon chemical potential ${\mu }_B$ in the forward rapidity range as compared to the mid-rapidity. The ${\mu }_B$ values in the rapidity range of $0<y<4.5$ for AFTER@LHC are comparable to that covered by the RHIC Beam Energy Scan program. Thus, a rapidity scan in the AFTER@LHC project provides a complementary approach to study the QCD phase diagram.

    ↳ nucl-thhep-exhep-phnucl-exPRC(2018)·17 citations
16. 16*

    Beam Spin Asymmetry in Electroproduction of Pseudoscalar or Scalar Meson Production off the Scalar Target

    Chueng-Ryong Ji🇺🇸 · Ho-Meoyng Choi🇰🇷 · Andrew Lundeen🇺🇸 · Bernard L. G. Bakker🇳🇱

    We discuss the electroproduction of pseudoscalar ($0^{-+}$) or scalar ($0^{++}$) meson production off the scalar target. The most general formulation of the differential cross section for the $0^{-+}$ or $0^{++}$ meson production process involves only one or two hadronic form factors, respectively, on a scalar target. The Rosenbluth-type separation of the differential cross section provides the explicit relation between the hadronic form factors and the different parts of the differential cross section in a completely model-independent manner. The absence of the beam spin asymmetry for the pseudoscalar meson production provides a benchmark for the experimental data analysis. The measurement of the beam spin asymmetry for the scalar meson production may also provide a unique opportunity not only to explore the imaginary part of the hadronic amplitude in the general formulation but also to examine the significance of the chiral-odd generalized parton distribution (GPD) contribution in the leading-twist GPD formulation.

    ↳ nucl-thhep-phPRD(2019)·4 citations
17. 17*

    Nonperturbative Renormalization of Operators in Near-Conformal Systems Using Gradient Flows

    Andrea Carosso🇺🇸 · Anna Hasenfratz🇺🇸 · Ethan T. Neil🇺🇸

    We propose a continuous real space renormalization group transformation based on gradient flow, allowing for a numerical study of renormalization without the need for costly ensemble matching. We apply our technique in a pilot study of SU$(3)$ gauge theory with $N_f=12$ fermions in the fundamental representation, finding the mass anomalous dimension to be ${\gamma }_m=0.23(6)$, consistent with other perturbative and lattice estimates. We also present the first lattice calculation of the nucleon anomalous dimension in this theory, finding ${\gamma }_N=0.05(5)$.

    ↳ hep-lathep-phhep-thPRL(2018)·57 citations
18. 18*

    The Effect of Multiplicity Cut on Particle Ratios at 7 TeV Proton-Proton Collisions

    Ehab Abbas🇪🇬

    The final state hadronic composition of proton-proton collisions at 7 TeV as a function of charged particle multiplicity density is studied. The thermal model is adjusted to match the experimental conditions in order to understand the effect of the experimental cuts on rapidity and multiplicity. This study indicates that the measured hadronic composition under a simultaneous cut on rapidity and multiplicity does not coincide with the fireball hadronic composition. Excluding proton to pion ratio, the adjusted model can explain the measured particle ratios. Therefore, the observed strangeness enhancement as a function of charged particle multiplicity density could be an effect of the experimental cuts.

    ↳ nucl-thhep-ph0 citations
19. 19*

    Instability of the Proca field on Kerr spacetime

    Sam R. Dolan🇬🇧

    A massive vector boson field in the vicinity of a rotating black hole is known to suffer an instability, due to the exponential amplification of (co-rotating, low-frequency) bound states by black hole superradiance. Here we calculate the bound state spectrum by exploiting the separation of variables recently achieved by Frolov, Krtous, Kubiznak and Santos (FKKS) for the Proca field on Kerr-(A)dS-NUT spacetimes of arbitrary dimension. Restricting to the 4D Kerr case, we first establish the relationship between the FKKS and Teukolsky variables in the massless case; obtain exact results for the angular eigenvalues in the marginally-bound case; and present a spectral method for solving the angular equation in the general case. We demonstrate that all three physical polarizations can be recovered from the FKKS ansatz, resolving an open question. We present numerical results for the instability growth rate for a selection of modes of all three polarizations, and discuss physical implications.

    ↳ gr-qchep-phPRD(2018)·116 citations
20. 20*

    QCD sum rules for the $\Delta$ isobar in neutron matter

    Jesuel Marques L.🇧🇷 · Su Houng Lee🇰🇷 · Aaron Park🇰🇷 · R. D. Matheus🇧🇷 · Kie Sang Jeong🇰🇷

    We study the properties of the $\Delta$ isobar in the symmetric and asymmetric nuclear matter using the QCD sum rules approach based on the energy dispersion relation. Allowing for different continuum thresholds for the polarization tensors with different dimensions, we find stable masses for the $\Delta$ in both the vacuum and the medium. Compared to the nucleon case, we find that the vector repulsion is smaller for the $\Delta$ while the scalar attraction is similar (75 MeV vector repulsion and 150 MeV scalar attraction in the symmetric matter). The smaller vector repulsion can be understood using the Pauli principle and a constituent quark model. Also the isospin dependence of the quasiparticle energy, which mainly comes from the vector self energy, is quite weak. We also allow for an explicit $\pi -N$ continuum contribution to the polarization function, but find its effect to be minimal. Phenomenological consequences of our results are discussed.

    ↳ nucl-thhep-phPRC(2018)·7 citations
21. 21*

    Cosmological Constant Effects on the Properties of Mass Twin Compact Stars

    Noshad Khosravi Largani🇮🇷 · David E. Alvarez-Castillo🇷🇺

    We present a systematic investigation of the cosmological constant effects in compact stars interiors in the framework of Einstein's gravity. Consideration of a cosmological constant $\Lambda$ in compact stars is motivated by the mechanism of acceleration of the observable universe, where $\Lambda$ is usually related to the dark energy. In particular, we consider compact star mass twins, hybrid neutron stars that populate both the second and third branch of the mass-radius diagram. For those models, the need of consideration of excluded volume effects in the equation of state, resulting from the finite size volume of nucleons, leads to a stiffening of matter causing compact stars to acquire higher mass and radius values. We demonstrate that certain values of the cosmological constant can also modify the compact star properties but in an opposite way. In addition, we find that the inclusion of $\Lambda$ can have a similar effect to the existence of pasta phases at the hadron-quark interface.

    ↳ astro-ph.HEastro-ph.SRhep-phnucl-thEPJ Web Conf.(2019)·6 citations
22. 22*

    Time evolution of a toy semiholographic glasma

    Christian Ecker🇦🇹 · Ayan Mukhopadhyay🇦🇹 · Florian Preis🇦🇹 · Anton Rebhan🇦🇹 · Alexander Soloviev🇦🇹

    We extend our previous study of a toy model for coupling classical Yang-Mills equations for describing overoccupied gluons at the saturation scale with a strongly coupled infrared sector modeled by AdS/CFT. Including propagating modes in the bulk we find that the Yang-Mills sector loses its initial energy to a growing black hole in the gravity dual such that there is a conserved energy-momentum tensor for the total system while entropy grows monotonically. This involves a numerical AdS simulation with a backreacted boundary source far from equilibrium.

    ↳ hep-thgr-qchep-phJHEP(2018)·19 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.