Wed·Jun 14, 2017Wednesday·June 14, 2017

1. 01*

   Experimental and theoretical premises of new stable hadron existence

   Yuriy Bazhutov🇷🇺 · Grigoriy Vereshkov🇷🇺 · Vladimir Kuksa🇷🇺

   The hypothesis of the new stable heavy hadrons existence is proposed which follows from Cosmic rays physics indirect data. It is shown that the hypothesis does not contradict Cosmochemical data, Cosmological test and the restrictions on New Physics effects. This conclusion is based on the most important property of the new hadrons - repulsion strong interaction with nucleons at large distance asymptote. This effect is substantiated theoretically in the framework of the low-energy hadron interaction model. Some extensions of Standard Model is considered where new stable and metastable quarks appear.

   hep-phInt.J.Mod.Phys.A(2017)·6 citations
2. 02*

   Decay of the dimuonium into a photon and a neutral pion

   Andrzej Czarnecki🇨🇦 · Savely G. Karshenboim🇩🇪

   We compute the decay rate of dimuonium into a neutral pion and a photon. We find that approximately one in 10^5 ortho-dimuonia decays into this channel. We also determine the contribution of the virtual photon-pion loop to the hyperfine splitting in dimuonium and reproduce its leading effect in the anomalous magnetic moment of the muon.

   hep-phPRD(2017)·2 citations
3. 03*

   Jet Identification with Zest

   Ankita Budhraja🇮🇳 · Ambar Jain🇮🇳

   We present a new observable zest and demonstrate its potential to differentiate between jets originated by gluons, top quark and vector bosons. Zest has salient properties such as boost invariance, stability against global color flow of partons and inclusion or exclusion of a few soft particles to the jet. For a gluon jet, zest distribution is also insensitive to the jet mass. We show that when zest is used in conjunction with other observables, it can yield high gluon rejection while retaining high signal sample.

   hep-phSpringer Proc.Phys.(2018)·0 citations
4. 04*

   On the difference of time-integrated $CP$ asymmetries in $D^0\to K^{+}{K}^{-}$ and $D^0\to {\pi }^{+}{\pi }^{-}$ decays: unparticle physics contribution

   Hosein Bagheri🇮🇷 · Mohammadmahdi Ettefaghi🇮🇷 · Reza Moazzemi🇮🇷

   The LHCb Collaboration has recently measured the difference of time-integrated $CP$ asymmetry in $D^0\to K^{+}{K}^{-}$ and $D^0\to {\pi }^{+}{\pi }^{-}$ decays, more precisely. The reported value is $\Delta A_{CP}=-0.10\pm 0.08(\text{stat})\pm 0.03(\text{syst})\%$ which indicates no evidence for $CP$ violation. We consider the possible unparticle physics contribution in this quantity and by using the LCHb data try to constrain the parameter space of unparticle stuff.

   hep-phPLB(2017)·2 citations
5. 05*

   Relativistic corrections to the static energy in terms of Wilson loops at weak coupling

   Clara Peset🇪🇸 · Antonio Pineda🇪🇸 · Maximilian Stahlhofen🇩🇪

   We consider the $\mathcal{O}(1/m)$ and the spin-independent momentum-dependent $\mathcal{O}(1/m^2)$ quasi-static energies of heavy quarkonium (with unequal masses). They are defined nonperturbatively in terms of Wilson loops. We determine their short-distance behavior through $\mathcal{O}({\alpha }^3)$ and $\mathcal{O}({\alpha }^2)$, respectively. In particular, we calculate the ultrasoft contributions to the quasi-static energies, which requires the resummation of potential interactions. Our results can be directly compared to lattice simulations. In addition, we also compare the available lattice data with the expectations from effective string models for the long-distance behavior of the quasi-static energies.

   hep-phhep-lathep-thEPJC(2017)·8 citations
6. 06*

   Broken $S_{3\mathrm{L}}^{}\times S_{3\mathrm{R}}^{}$ Flavor Symmetry and Leptonic CP Violation

   Zong-guo Si🇨🇳 · Xing-hua Yang🇨🇳 · Shun Zhou🇨🇳

   In the framework of canonical seesaw model, we present a simple but viable scenario to explicitly break an $S_{3\mathrm{L}}^{}\times S_{3\mathrm{R}}^{}$ flavor symmetry in the leptonic sector. It turns out that the leptonic flavor mixing matrix is completely determined by the mass ratios of charged leptons (i.e., $m_e^{}/m_{\mu }^{}$ and $m_{\mu }^{}/m_{\tau }^{}$) and those of light neutrinos (i.e., $m_1^{}/m_2^{}$ and $m_2^{}/m_3^{}$). The latest global-fit results of three neutrino mixing angles $\{{\theta }_{12}^{},{\theta }_{13}^{},{\theta }_{23}^{}\}$ and two neutrino mass-squared differences $\{\Delta m_{21}^2,\Delta m_{31}^2\}$ at the $3\sigma$ level are used to constrain the parameter space of $\{m_1^{}/m_2^{},m_2^{}/m_3^{}\}$. The predictions for the mass spectrum and flavor mixing are highlighted: (1) The neutrino mass spectrum shows a hierarchical pattern and a normal ordering, e.g., $m_1^{}\approx 2.2\mathrm{meV}$, $m_2^{}\approx 8.8\mathrm{meV}$ and $m_3^{}\approx 52.7\mathrm{meV}$; (2) Only the first octant of ${\theta }_{23}^{}$ is allowed, namely, $41.8^{\circ }\lesssim {\theta }_{23}^{}\lesssim 43.3^{\circ }$; (3) The Dirac CP-violating phase $\delta \approx -22^{\circ }$ deviates significantly from the maximal value $-90^{\circ }$. All these predictions are ready to be tested in the ongoing and forthcoming neutrino oscillation experiments. Moreover, we demonstrate that the cosmological matter-antimatter asymmetry can be explained via resonant leptogenesis, including the individual lepton-flavor effects. In our scenario, the leptonic CP violation at low- and high-energy scales are closely connected.

   hep-phCPC(2017)·6 citations
7. 07*

   Extra Quarks Decaying to Dark Matter Beyond the Narrow Width Approximation

   Hugo Prager🇬🇧 · Stefano Moretti🇬🇧 · Dermot O'Brien🇬🇧 · Luca Panizzi🇬🇧

   We explore the effects induced by a finite width in processes of pair production of a heavy top-quark partner and its subsequent decay into a bosonic Dark Matter (DM) candidate -- either scalar or vector -- and a SM up-type quark at the Large Hadron Collider (LHC). We discuss the configurations of masses, widths and couplings where this phenomenology can be important in a simple model with just one such objects. Finally, we emphasise the correct definition of signal and background to be adopted as well as stress the importance of new dedicated experimental searches.

   hep-ph7 citations
8. 08*

   Large width effects in processes of production of extra quarks decaying to Dark Matter at the LHC

   Hugo Prager🇬🇧 · Stefano Moretti🇬🇧 · Dermot O'Brien🇬🇧 · Luca Panizzi🇬🇧

   This paper explores the effects of finite width in processes of pair production of a heavy eXtra Quark (XQ) with charge 2/3 and its subsequent decay into a Dark Matter (DM) candidate -- either scalar or vector -- and Standard Model (SM) up-type quarks at the Large Hadron Collider (LHC). This dynamics has been ignored so far in standard experimental searches of heavy quarks decaying to DM and we assess herein the regions of validity of current approaches, based on the assumption that the XQ has a narrow width. Further, we discuss the configurations of masses, widths and couplings where the latter breaks down.

   hep-phPoS(2018)·7 citations
9. 09*

   Determining the effective Wilson coefficient $a_2$ in terms of $BR(B_s\to {\eta }_c\varphi )$ and evaluating $BR(B_s\to {\eta }_c{f}_0(980))$

   Hong-Wei Ke · Xue-Qian Li🇨🇳

   In this work, we investigate decays of $B_s\to {\eta }_c\varphi$ and $B_s\to {\eta }_c{f}_0(980)$ in a theoretical framework. The calculation is based on the postulation that $f_0(980)$ and $f_0(500)$ are mixtures of pure quark states $\frac{1}{\sqrt{2}}(\bar{u}u+\bar{d}d)$ and $\bar{s}s$. The hadronic matrix elements for $B_s\to \varphi$ and $B_s\to f_0(980)$ are calculated in the light-front quark model and the important Wilson coefficient $a_2$ which is closely related to non-perturbative QCD is extracted. However, our numerical results indicate that no matter how to adjust the mixing parameter to reconcile contributions of $f_0(980)$ and $f_0(500)$, one cannot make the theoretical prediction on $B_s\to {\eta }_c+{\pi }^{+}{\pi }^{-}$ to meet the data. Moreover, the new measurement of $BR(B_s\to J/\psi +f_0(500))<1.7\times 10^{-6}$ also negates the mixture scenario. Thus, we conclude that the recent data suggest that $f_0(980)$ is a four quark state ( tetraquark or $K\bar{K}$ molecule ), at least the fraction of its pure quark constituents is small.

   hep-phPRD(2017)·5 citations
10. 10*

    Universality of next-to-leading power threshold effects for colourless final states in hadronic collisions

    V. Del Duca🇨🇭 · E. Laenen🇳🇱 · L. Magnea🇮🇹 · L. Vernazza🇬🇧 · C. D. White🇬🇧

    We consider the production of an arbitrary number of colour-singlet particles near partonic threshold, and show that next-to-leading order cross sections for this class of processes have a simple universal form at next-to-leading power (NLP) in the energy of the emitted gluon radiation. Our analysis relies on a recently derived factorisation formula for NLP threshold effects at amplitude level, and therefore applies both if the leading-order process is tree-level and if it is loop-induced. It holds for differential distributions as well. The results can furthermore be seen as applications of recently derived next-to-soft theorems for gauge theory amplitudes. We use our universal expression to re-derive known results for the production of up to three Higgs bosons at NLO in the large top mass limit, and for the hadro-production of a pair of electroweak gauge bosons. Finally, we present new analytic results for Higgs boson pair production at NLO and NLP, with exact top-mass dependence.

    hep-phJHEP(2017)·97 citations
11. 11*

    Electromagnetic charge radius of the pion at high precision

    B. Ananthanarayan🇮🇳 · Irinel Caprini🇷🇴 · Diganta Das🇮🇳

    We present a determination of the pion charge radius from high precision data on the pion vector form factor from both timelike and spacelike regions, using a novel formalism based on analyticity and unitarity. At low energies, instead of the poorly known modulus of the form factor, we use its phase, known with high accuracy from Roy equations for $\pi \pi$ elastic scattering via the Fermi-Watson theorem. We use also the values of the modulus at several higher timelike energies, where the data from $e^{+}{e}^{-}$-annihilation and $\tau$-decay are mutually consistent, as well as the most recent measurements at spacelike momenta. The experimental uncertainties are implemented by Monte-Carlo simulations. The results, which do not rely on a specific parametrization, are optimal for the given input information and do not depend on the unknown phase of the form factor above the first inelastic threshold. Our prediction for the charge radius of the pion is $r_{\pi }=(0.657\pm 0.003)\text{fm}$, which amounts to an increase in precision by a factor of about 2.7 compared to the PDG average.

    hep-phPRL(2017)·43 citations
12. 12*

    Uncovering new strong dynamics via topological interactions at the 100 TeV collider

    Emiliano Molinaro🇩🇰 · Francesco Sannino🇩🇰 · Anders Eller Thomsen🇩🇰 · Natascia Vignaroli🇩🇰

    In models of composite Higgs dynamics new composite pseudoscalars can interact with the Higgs and electroweak gauge bosons via anomalous interactions, stemming from the topological sector of the underlying theory. We show that a future 100 TeV proton-proton collider (FCC-pp) will be able to test this important sector and thus shed light on the strong dynamics which generates the Higgs and other composite states. To elucidate our results we focus on the topological interactions of a minimal composite Higgs model with a fermionic ultraviolet completion, based on the coset $\text{SU}(4)/\text{Sp}(4)$. We suggest the strategy to test these interactions at the FCC-pp and analyse the expected reach.

    hep-phhep-exPRD(2017)·10 citations
13. 13*

    Leading order NRQCD and Light-Cone Analysis of Exclusive Charmonia Production in Radiative $Z$-boson Decays

    A. V. Luchinsky🇷🇺

    The presented paper is devoted to theoretical analysis of charmonium mesons ${\eta }_c$, $J/\psi$, ${\chi }_{c0,1,2}$, and $h_c$ production in exclusive radiative $Z$ boson decays in the frameworks of Nonrelativistic Chromodynamic and amplitude expansion on the light-cone. In the framework of light-cone expansion amplitudes and widths of all processes are described with one universal relation. It is interesting to note that from this relation it follows automatically which component of $Z$ boson (either vector or axial) gives contribution to the width of the particular decay. It is shown that the effect of internal quark motion almost doubles theoretical predictions for production of $S$-wave charmonia and ${\chi }_{c1}$ meson.

    hep-ph12 citations
14. 14*

    Point Sources from Dissipative Dark Matter

    Prateek Agrawal🇺🇸 · Lisa Randall🇺🇸

    If a component of dark matter has dissipative interactions, it can cool to form compact astrophysical objects with higher density than that of conventional cold dark matter (sub)haloes. Dark matter annihilations might then appear as point sources, leading to novel morphology for indirect detection. We explore dissipative models where interaction with the Standard Model might provide visible signals, and show how such objects might give rise to the observed excess in gamma rays arising from the galactic center.

    hep-phastro-ph.GAastro-ph.HEJCAP(2017)·35 citations
15. 15*

    $Z^{\prime }$ portal to Chern-Simons Dark Matter

    Giorgio Arcadi🇩🇪 · Pradipta Ghosh🇮🇳 · Yann Mambrini🇫🇷 · Mathias Pierre🇫🇷 · Farinaldo S. Queiroz🇩🇪

    We study the phenomenological credibility of a vectorial dark matter, coupled to a $Z^{\prime }$ portal through Chern-Simons interaction. We scrutinize two possibilities of connecting a $Z^{\prime }$ with the Standard Model: (1) through kinetic mixing and (2) from a second Chern-Simons interaction. Both scenarios are characterized by suppressed nuclear recoil scatterings, rendering direct detection searches not promising. Indirect detection experiments, on the other hand, furnish complementary limits for TeV scale masses, specially with the CTA. Searches for mono-jet and dileptons signals at the LHC are important to partially probe the kinetic mixing setup. Finally we propose an UV completion of the Chern-Simons Dark Matter framework.

    hep-phhep-exJCAP(2017)·32 citations
16. 16*

    Quantum gravity corrections to gauge theories with a cutoff regularization

    G. Cynolter🇭🇺 · E. Lendvai🇭🇺

    Gravity can be considered as an effective quantum field theory with reliable, but limited predictions. Though the influence of gravity on gauge and other interactions of elementary particles is still an open question. We calculate the lowest order quantum gravity contributions to the QED beta function in an effective field theory picture with a momentum cutoff. We use a recently proposed 4 dimensional improved momentum cutoff that preserves gauge and Lorentz symmetries. We find that there is a non-vanishing quadratic contribution to the photon 2-point function but after renormalization that does not lead to the running of the original coupling. We comment on corrections to the other gauge interactions and Yukawa couplings of heavy fermions. We argue that gravity cannot turn gauge interactions asymptotically free.

    hep-phgr-qc0 citations
17. 17*

    The strong coupling from a nonperturbative determination of the $\Lambda$ parameter in three-flavor QCD

    M. Bruno🇺🇸 · M. Dalla Brida🇮🇹 · P. Fritzsch🇨🇭 · T. Korzec🇩🇪 · A. Ramos🇨🇭 · S. Schaefer🇩🇪 · H. Simma🇩🇪 · S. Sint🇮🇪 · R. Sommer🇩🇪

    We present a lattice determination of the $\Lambda$ parameter in three-flavor QCD and the strong coupling at the Z pole mass. Computing the nonperturbative running of the coupling in the range from $0.2$GeV to $70$GeV, and using experimental input values for the masses and decay constants of the pion and the kaon, we obtain ${\Lambda }_{\overline{\mathrm{MS}}}^{(3)}=341(12)$MeV. The nonperturbative running up to very high energies guarantees that systematic effects associated with perturbation theory are well under control. Using the four-loop prediction for ${\Lambda }_{\overline{\mathrm{MS}}}^{(5)}/{\Lambda }_{\overline{\mathrm{MS}}}^{(3)}$ yields ${\alpha }_{\overline{\mathrm{MS}}}^{(5)}(m_{\mathrm{Z}})=0.11852(84)$.

    ↳ hep-lathep-exhep-phPRL(2017)·185 citations
18. 18*

    Diffuse neutrino supernova background as a cosmological test

    J. Barranco🇲🇽 · Argelia Bernal🇲🇽 · D. Delepine🇲🇽

    The future detection and measurement of the diffuse neutrino supernova background will shed light on the rate of supernovae events in the Universe, the star formation rate and the neutrino spectrum from each supernova. Little has been said about what those measurements will tell us about the expansion history of the universe. The purpose of this article is to show that the detection of the diffuse supernova neutrino background will be a complementary tool for the study and possible discrimination of cosmological models. In particular, we study three different cosmological models: the $\Lambda$ Cold Dark Matter model, the Logotropic universe and a bulk viscous matter-dominated universe. By fitting the free parameters of each model with the supernova Ia probe, we found that the predicted number of events computed with the best fit parameters for the $\Lambda$-Cold dark matter model and with the Logotropic model are the same, while a bulk viscous matter-dominated cosmological model predicts $\sim 3$ times more events. We show that the current limit set by Super-Kamiokande on the diffuse supernova neutrino background flux gives complementary constraints on the free parameters of a bulk viscous matter-dominated universe. Furthermore, this limit implies, within a $\Lambda$ Cold Dark Matter model, that the universe should be expanding with $H_0>21.5Km/sec/Mpc$ independently of the content of dark matter ${\Omega }_m$.

    ↳ astro-ph.COastro-ph.HEgr-qchep-phJ.Phys.G(2018)·12 citations
19. 19*

    Lunar Mass Black Holes from QCD Axion Cosmology

    Tanmay Vachaspati🇺🇸

    In the QCD axion scenario, a network of domain walls bounded by cosmic strings fragments into pieces. As these fragments collapse, some of them will form black holes. With standard QCD axion parameters, the black holes will have lunar masses ($M_{\mathrm{bh}}\sim 10^{-8}{\mathrm{M}}_{\odot }$). Even though their number density is difficult to estimate, arguments suggest that they can constitute a reasonable fraction of the critical cosmological density.

    ↳ hep-thastro-ph.COgr-qchep-ph32 citations
20. 20*

    Convergent series for polynomial lattice models with complex actions

    Vasily Sazonov🇦🇹

    Lattice models with complex actions are important for the understanding of matter at finite densities, but not accessible by the standard Monte Carlo techniques due to the sign problem. Here we derive a new approach for avoiding the complex action/sign problem, by extending the method of convergent series with a non-Gaussian initial approximation. The main features of the new series are demonstrated on the example of the two dimensional oscillating integral.

    ↳ hep-lathep-phhep-thMod.Phys.Lett.A(2019)·3 citations
21. 21*

    Medium-modification of photon-tagged jets in $AA$ collisions

    B.G. Zakharov🇷🇺

    We study nuclear modification of the photon-tagged jets in $AA$ collisions within the jet quenching scheme based on the light-cone path integral approach to the induced gluon emission. The calculations are performed for running coupling. Collisional energy loss is treated as a perturbation to the radiative mechanism. We obtain a reasonable agreement with the recent data from the STAR Collaboration on the mid-rapidity nuclear modification factor $I_{AA}$ for Au+Au collisions at $\sqrt{s}=200$ GeV for parametrization of running ${\alpha }_s$ consistent with that necessary for description of the data on suppression of the high-$p_T$ spectra.

    ↳ nucl-thhep-phJ.Exp.Theor.Phys.(2017)·4 citations
22. 22*

    Disentangling stopped proton and inclusive net-proton fluctuations at RHIC

    D. K. Mishra🇮🇳 · P. Garg🇺🇸

    The recent results on net-proton and net-charge multiplicity fluctuations from the beam energy scan program at RHIC have drawn much attention to explore the critical point in the QCD phase diagram. Experimentally measured protons contain contribution from various processes such as secondaries from higher mass resonance decay, production process, and protons from the baryon stopping. Further, these contributions also fluctuate from event to event and can contaminate the dynamical fluctuations due to the critical point. We present the contribution of stopped proton and produced proton fluctuations in the net-proton multiplicity fluctuation in \auau collisions measured by STAR experiment at RHIC. The produced net-proton multiplicity fluctuations using cumulants and their ratios are studied as a function collision energies. After removing the stopped proton contribution from the inclusive proton multiplicity distribution, a non-monotonic behavior is even more pronounced in the net-proton fluctuations around \sqsn = 19.6 GeV, both in $S\sigma$ and $\kappa {\sigma }^2$. The present study will be useful to understand the fluctuations originating due to critical point.

    ↳ nucl-thhep-phnucl-ex3 citations
23. 23*

    A Bayesian Framework for Cosmic String Searches in CMB Maps

    Razvan Ciuca🇨🇦 · Oscar F. Hernández🇨🇦

    There exists various proposals to detect cosmic strings from Cosmic Microwave Background (CMB) or 21 cm temperature maps. Current proposals do not aim to find the location of strings on sky maps, all of these approaches can be thought of as a statistic on a sky map. We propose a Bayesian interpretation of cosmic string detection and within that framework, we derive a connection between estimates of cosmic string locations and cosmic string tension $G\mu$. We use this Bayesian framework to develop a machine learning framework for detecting strings from sky maps and outline how to implement this framework with neural networks. The neural network we trained was able to detect and locate cosmic strings on noiseless CMB temperature map down to a string tension of $G\mu =5\times 10^{-9}$ and when analyzing a CMB temperature map that does not contain strings, the neural network gives a 0.95 probability that $G\mu \le 2.3\times 10^{-9}$.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2017)·22 citations
24. 24*

    Inflation from Supersymmetry Breaking

    Ignatios Antoniadis🇫🇷 · Auttakit Chatrabhuti🇹🇭 · Hiroshi Isono🇹🇭 · Rob Knoops🇹🇭

    We explore the possibility that inflation is driven by supersymmetry breaking with the superpartner of the goldstino (sgoldstino) playing the role of the inflaton. Moreover, we impose an R-symmetry that allows to satisfy easily the slow-roll conditions, avoiding the so-called $\eta$-problem, and leads to two different classes of small field inflation models; they are characterised by an inflationary plateau around the maximum of the scalar potential, where R-symmetry is either restored or spontaneously broken, with the inflaton rolling down to a minimum describing the present phase of our Universe. To avoid the Goldstone boson and remain with a single (real) scalar field (the inflaton), R-symmetry is gauged with the corresponding gauge boson becoming massive. This framework generalises a model studied recently by the present authors, with the inflaton identified by the string dilaton and R-symmetry together with supersymmetry restored at weak coupling, at infinity of the dilaton potential. The presence of the D-term allows a tuning of the vacuum energy at the minimum. The proposed models agree with cosmological observations and predict a tensor-to-scalar ratio of primordial perturbations $10^{-9}\lesssim r\lesssim 10^{-4}$ and an inflation scale $10^{10}$ GeV $\lesssim H_{\ast }\lesssim 10^{12}$ GeV. $H_{\ast }$ may be lowered up to electroweak energies only at the expense of fine-tuning the scalar potential.

    ↳ hep-thhep-phEPJC(2017)·31 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.