Thu·Jun 29, 2017Thursday·June 29, 2017

1. 01*

   Displaced Vertices from Pseudo-Dirac Dark Matter

   Alessandro Davoli🇮🇹 · Andrea De Simone🇮🇹 · Thomas Jacques🇮🇹 · Verónica Sanz🇬🇧

   Displaced vertices are relatively unusual signatures for dark matter searches at the LHC. We revisit the model of pseudo-Dirac dark matter (pDDM), which can accommodate the correct relic density, evade direct detection constraints, and generically provide observable collider signatures in the form of displaced vertices. We use this model as a benchmark to illustrate the general techniques involved in the analysis, the complementarity between monojet and displaced vertex searches, and provide a comprehensive study of the current bounds and prospective reach.

   hep-phJHEP(2017)·27 citations
2. 02*

   Thermodynamical properties of a neutral vector boson gas in a constant magnetic field

   G. Quintero Angulo🇨🇺 · A. Pérez Martínez🇨🇺 · H. Pérez Rojas🇨🇺

   The thermodynamical properties of a neutral vector boson gas in a constant magnetic field are studied starting from the spectrum given by Proca formalism. Bose Einstein Condensation (BEC) and magnetization are obtained, for the three and one dimensional cases, in the limit of low temperatures. In three dimensions the gas undergoes a phase transition to an usual BEC in which the critical temperature depends on the magnetic field. In one dimension a diffuse condensate appears as for the charged vector boson gas. In both cases, the condensation is reached not only by decreasing the temperature but also by increasing the magnetic field. In three and one dimensions self-magnetization is possible. The anisotropy in the pressures due to axial symmetry imposed to the system by the magnetic field is also discussed. The astrophysical implications are commented.

   hep-phPRC(2017)·17 citations
3. 03*

   Electroweak corrections to diphoton plus jets

   Mauro Chiesa🇩🇪 · Nicolas Greiner🇨🇭 · Marek Schoenherr🇨🇭 · Francesco Tramontano🇮🇹

   We calculate the next-to-leading order electroweak corrections to the production of a photon pair in association with zero, one and two jets at the LHC. We use GoSam and Sherpa to obtain the results in a fully automated way. For a typical set of fiducial cuts the electroweak corrections lead to a modification of the total cross section of up to 3 per cent, depending on the jet multiplicity. We find substantial contributions in differential distributions, leading to tens of per cent corrections for phase space regions within the reach of the LHC. Furthermore we investigate the importance of photon induced processes as well as subleading contributions. Photon induced processes are found to be negligible, subleading contributions can have a sizeable impact however they can be removed by appropriate phase space cuts.

   hep-phJHEP(2017)·43 citations
4. 04*

   Dissecting Multi-Photon Resonances at the Large Hadron Collider

   B.C. Allanach (1)🇬🇧 · D. Bhatia (2)🇮🇳 · A.M. Iyer (2) ((1) Cambridge (2) TIFR)🇮🇳

   We examine the phenomenology of the production, at the 13 TeV Large Hadron Collider (LHC), of a heavy resonance $X$, which decays via other new on-shell particles $n$ into multi- (i.e.\ three or more) photon final states. In the limit that $n$ has a much smaller mass than $X$, the multi-photon final state may dominantly appear as a two photon final state because the $\gamma$s from the $n$ decay are highly collinear and remain unresolved. We discuss how to discriminate this scenario from $X\to \gamma \gamma$: rather than discarding non-isolated photons, it is better instead to relax the isolation criterion and instead form photon jet substructure variables. The spins of $X$ and $n$ leave their imprint upon the distribution of pseudorapidity gap $\Delta \eta$ between the apparent two photon states. Depending on the total integrated luminosity, this can be used in many cases to claim discrimination between the possible spin choices of $X$ and $n$, although the case where $X$ and $n$ are both scalar particles cannot be discriminated from the direct $X\to \gamma \gamma$ decay in this manner. Information on the mass of $n$ can be gained by considering the mass of each photon jet.

   hep-phhep-exEPJC(2017)·10 citations
5. 05*

   Quark-diquark structure and masses of doubly charmed baryons

   V. V. Kiselev🇷🇺 · A. V. Berezhnoy🇷🇺 · A. K. Likhoded🇷🇺

   The finite size of doubly heavy diquark gives a positive correction to the masses of baryons calculated in the local diquark approximation. We evaluate this correction for the basic states of doubly charmed baryons to give quite accurate predictions actual for current searches of those baryons at LHCb: $m[{{\Xi }_{cc}^{1/2}}^{+}]\approx m[{{\Xi }_{cc}^{1/2}}^{++}]=3615\pm 55$ MeV and $m[{{\Xi }_{cc}^{3/2}}^{+}]\approx m[{{\Xi }_{cc}^{3/2}}^{++}]=3747\pm 55$ MeV.

   hep-phPhys.Atom.Nucl.(2018)·33 citations
6. 06*

   Bottomonia Suppression in Heavy Ion Collisions from AdS/CFT

   N. N. Barnard🇿🇦 · W. A. Horowitz🇿🇦

   We compute for the first time the suppression of bottomonia in a strongly coupled QGP and compare the results to those from a weakly coupled QGP. Using imaginary time techniques we numerically determine the real and imaginary parts of the ground state binding energy of the bottomonia in one potential computed from AdS/CFT and another computed from pQCD. We then use these binding energies in a suppression model to determine the ${\rm Y}$(1S) nuclear modification factor in ${\sqrt{s}}_{NN}=2.76$ TeV Pb+Pb collisions. AdS/CFT significantly overpredicts the suppression compared to data, although the predictive power of our calculation is limited by its significant sensitivity to the exact details of the suppression model.

   hep-phnucl-thPRC(2020)·5 citations
7. 07*

   Closing in on the chargino contribution to the muon g-2 in the MSSM: current LHC constraints

   Kaoru Hagiwara🇯🇵 · Kai Ma🇨🇳 · Satyanarayan Mukhopadhyay🇺🇸

   We revisit the current LHC constraints on the electroweak-ino sector parameters in the minimal supersymmetric standard model (MSSM) that are relevant to explaining the $(g-2{)}_{\mu }$ anomaly via the dominant chargino and muon sneutrino loop. Since the LHC bounds on electroweak-inos become weaker if they decay via an intermediate stau or a tau sneutrino instead of the first two generation sleptons, we perform a detailed analysis of the scenario with a bino as the lightest supersymmetric particle (LSP) and a light stau as the next-to-lightest one (NLSP). Even in this scenario, the chargino sector parameters in the MSSM that can account for the $(g-2{)}_{\mu }$ anomaly within $1\sigma$ are already found to be significantly constrained by the 8 TeV LHC and the available subset of the 13 TeV LHC limits. We also estimate the current LHC exclusions in the left-smuon (and/or left-selectron) NLSP scenario from multilepton searches, and further combine the constraints from the multi-tau and multi-lepton channels for a mass spectrum in which all three generations of sleptons are lighter than the chargino. In the latter two cases, small corners of the $1\sigma$ favoured region for $(g-2{)}_{\mu }$ are still allowed at present.

   hep-phhep-exPRD(2018)·35 citations
8. 08*

   Interaction and Identification of the Doubly Heavy Di-Hadronic Molecules

   D. P. Rathaud🇮🇳 · Ajay Kumar Rai🇮🇳

   We study the interesting problem of interaction and identification of the hadronic molecules which seem to be deuteron-like structure. In particular, we propose a binding mechanism in which One Boson Exchange Potential plus Yukawa screen-like potential is applied in their relative s-wave state. We propose the dipole-like interaction between two color neutral states to form a hadronic molecule. For the identification of the hadronic molecules, the Weinberg's compositeness theorem is used to distinguish the molecule from confined (elementary) state. The present formalism predict some di-hadronic molecular states, involving quarks (s, c, b or $\overline{s}$, $\overline{c}$, $\overline{b}$) as a constituents, namely, $pn$, $K\overline{K}$, $\rho \overline{\rho }$, $K^{\ast }\overline{K^{\ast }}$, $D\overline{D^{\ast }}$($\overline{D}{D}^{\ast }$), $D^{\ast }\overline{D^{\ast }}$, $B\overline{B^{\ast }}$, $B^{\ast }\overline{B^{\ast }}$, $D^{\ast \pm }\overline{D_1^0}$, $D^0\overline{K^{\pm }}$, $D^{\ast 0}\overline{K^{\pm }}$, with their possible quantum numbers.

   hep-phnucl-th5 citations
9. 09*

   Clockwork graviton contributions to muon $g-2$

   Deog Ki Hong🇰🇷 · Du Hwan Kim🇰🇷 · Chang Sub Shin🇰🇷

   The clockwork mechanism for gravity introduces a tower of massive graviton modes, "clockwork gravitons," with a very compressed mass spectrum, whose interaction strengths are much stronger than that of massless gravitons. In this work, we compute the lowest order contributions of the clockwork gravitons to the anomalous magnetic moment, $g-2$, of muon in the context of extra dimensional model with a five dimensional Planck mass, $M_5$. We find that the total contributions are rather insensitive to the detailed model parameters, and determined mostly by the value of $M_5$. In order to account for the current muon $g-2$ anomaly, $M_5$ should be around $0.2\mathrm{TeV}$, and the size of the extra dimension has to be quite large, $l_5\gtrsim 10^{-7}$m. For $M_5\gtrsim 1\mathrm{TeV}$, the clockwork graviton contributions are too small to explain the current muon $g-2$ anomaly. We also compare the clockwork graviton contributions with other extra dimension models such as Randall-Sundrum models or large extra dimension models. We find that the leading contributions in the small curvature limit are universal, but the cutoff-independent subleading contributions vary for different background geometries and the clockwork geometry gives the smallest subleading contributions.

   hep-phPRD(2018)·22 citations
10. 10*

    Towards a medium-scale axion helioscope and haloscope

    V. Anastassopoulos · F. Avignone · A. Bykov · G. Cantatore · S.A. Cetin · A. Derbin · I. Drachnev · R. Djilkibaev · V. Eremin · H. Fischer · A. Gangapshev · A. Gardikiotis and 23 other authors

    We discuss the physics case for and the concept of a medium-scale axion helioscope with sensitivities in the axion-photon coupling a few times better than CERN Axion Solar Telescope (CAST). Search for an axion-like particle with these couplings is motivated by several persistent astrophysical anomalies. We present early conceptual design, existing infrastructure, projected sensitivity and timeline of such a helioscope (Troitsk Axion Solar Telescope Experiment, TASTE) to be constructed in the Institute for Nuclear Research, Troitsk, Russia. The proposed instrument may be also used for the search of dark-matter halo axions.

    hep-phastro-ph.HEhep-exJINST(2017)·43 citations
11. 11*

    Revisit assignments of the new excited ${\Omega }_c$ states with QCD sum rules

    Zhi-Gang Wang🇨🇳 · Xing-Ning Wei🇨🇳 · Ze-Hui Yan🇨🇳

    In this article, we distinguish the contributions of the positive parity and negative parity ${\Omega }_c$ states, study the masses and pole residues of the 1S, 1P, 2S and 2P ${\Omega }_c$ states with the spin $J=\frac{1}{2}$ and $\frac{3}{2}$ using the QCD sum rules in a consistent way, and revisit the assignments of the new narrow excited ${\Omega }_c^0$ states. The predictions support assigning the ${\Omega }_c(3000)$ to be the 1P ${\Omega }_c$ state with $J^P={\frac{1}{2}}^{-}$, assigning the ${\Omega }_c(3090)$ to be the 1P ${\Omega }_c$ state with $J^P={\frac{3}{2}}^{-}$ or the 2S ${\Omega }_c$ state with $J^P={\frac{1}{2}}^{+}$, and assigning ${\Omega }_c(3119)$ to be the 2S ${\Omega }_c$ state with $J^P={\frac{3}{2}}^{+}$.

    hep-phEPJC(2017)·21 citations
12. 12*

    The Standard Model and low-energy experiments: from lepton-flavour violation to dark photons

    Giovanni Marco Pruna🇨🇭

    This note is a concise theoretical summary of the first session on new physics searches at the high-intensity frontier of the IFAE2017 Conference. Recent theoretical developments related to muonic lepton-flavour violation and $g-2$ are reviewed.

    hep-phNuovo Cim.C(2018)·1 citation
13. 13*

    R-Parity Violation at the LHC

    Daniel Dercks🇩🇪 · Herbi Dreiner🇩🇪 · Manuel E. Krauss🇩🇪 · Toby Opferkuch🇩🇪 · Annika Reinert🇩🇪

    We investigate the phenomenology of the MSSM extended by a single R-parity violating coupling at the unification scale. For all R-parity violating couplings, we discuss the evolution of the particle spectra through the renormalization group equations and the nature of the lightest supersymmetric particle (LSP) within the CMSSM, as an example of a specific complete supersymmetric model. We use the nature of the LSP to classify the possible signatures. For each possible scenario we present in detail the current LHC bounds on the supersymmetric particle masses, typically obtained using simplified models. From this we determine the present coverage of R-parity violating models at the LHC. We find several gaps, in particular for a stau-LSP, which is easily obtained in R-parity violating models. Using the program CheckMATE we recast existing LHC searches to set limits on the parameters of all R-parity violating CMSSMs. We find that virtually all of them are either more strongly constrained or similarly constrained in comparison to the R-parity conserving CMSSM, including the $\bar{U}\bar{D}\bar{D}$ models. For each R-parity violating CMSSM we then give the explicit lower mass bounds on all relevant supersymmetric particles.

    hep-phhep-exEPJC(2017)·65 citations
14. 14*

    CP violation effects in the diphoton spectrum of heavy scalars

    Ligong Bian🇨🇳 · Ning Chen🇨🇳 · Yongchao Zhang🇺🇸

    In a class of new physics models, an extended Higgs sector and new CP-violating sources are simultaneously present in order to explain the baryon asymmetry in the Universe. The aim of this work is to study the implications of beyond the Standard Model (SM) CP violation for the searches of heavy scalars at the LHC. In particular, we focus on the diphoton channel searches in the CP-violating two-Higgs-doublet model (CPV 2HDM). To have a sizable CPV in the scalar sector, the two heavy neutral scalars in 2HDM tend to be nearly degenerate. The theoretical constraints of unitarity, perturbativity and vacuum stability are considered, which requires that the heavy scalars $M_H\lesssim 1$ TeV in a large region of the parameter space. The experimental limits are also taken into account, including the direct searches of heavy neutral scalars in the final state of the SM $h$, $W$ and $Z$ bosons, the differential $t\bar{t}$ data, those from the charged scalar sector which is implied by the oblique $T$ parameter, as well as the precise measurements of the electric dipole moments of electron and mercury. The quantum interference effects between the resonances and the SM background are crucially important for the diphoton signals, and the CPV mixing of the quasi-degenerate heavy scalars could enhance significantly the resonance peak. With an integrated luminosity of 3000 fb${}^{-1}$ at the LHC, almost the whole parameter space of CPV 2HDM could be probed in the diphoton channel, and the CPV could also be directly detected via the diphoton spectrum.

    hep-phhep-exPRD(2017)·17 citations
15. 15*

    The (de)-confinement transition in tachyonic matter at finite temperature

    Adamu Issifu🇧🇷 · Francisco A. Brito🇧🇷

    In this paper we present a QCD motivated model that mimics QCD theory. We examine the characteristics of the gauge field coupled with the color dielectric function ($G$) in the presence of temperature ($T$). The aim is to achieve confinement at low temperatures $T<T_c$, ($T_c$, is the critical temperature), similar to what occurs among quarks and gluons in hadrons at low energies. Also, we investigate scalar glueballs and QCD string tension and effect of temperature on them. To achieve this, we use the phenomenon of color dielectric function in gauge fields in a slowly varying tachyon medium. This method is suitable for analytically computing the resulting potential, glueball masses and the string tension associated with the confinement at a finite temperature. We demonstrate that the color dielectric function changes Maxwell's equation as a function of the tachyon fields and induces the electric field in a way that brings about confinement during the tachyon condensation below the critical temperature.

    ↳ hep-thhep-phAdv.High Energy Phys.(2019)·11 citations
16. 16*

    Feynman-Hellmann theorem for resonances and the quest for QCD exotica

    J. Ruiz de Elvira🇨🇭 · U.-G. Meißner🇩🇪 · A. Rusetsky🇩🇪 · G. Schierholz🇩🇪

    The generalization of the Feynman-Hellmann theorem for resonance states in quantum field theory is derived. On the basis of this theorem, a criterion is proposed to study the possible exotic nature of certain hadronic states emerging in QCD. It is shown that this proposal is supported by explicit calculations in Chiral Perturbation Theory and by large-$N_c$ arguments. Analyzing recent lattice data on the quark mass dependence in the pseudoscalar, vector meson, baryon octet and baryon decuplet sectors, we conclude that, as expected, these are predominately quark-model states, albeit the corrections are non-negligible.

    ↳ hep-lathep-phnucl-thEPJC(2017)·25 citations
17. 17*

    New Large Volume Solutions

    Ross Altman🇺🇸 · Yang-Hui He🇬🇧 · Vishnu Jejjala🇿🇦 · Brent D. Nelson🇺🇸

    In previous work, we have commenced the task of unpacking the $473,800,776$ reflexive polyhedra by Kreuzer and Skarke into a database of Calabi-Yau threefolds (see http://www.rossealtman.com). In this paper, following a pedagogical introduction, we present a new algorithm to isolate Swiss cheese solutions characterized by "holes," or small 4-cycles, descending from the toric divisors inherent to the original four dimensional reflexive polyhedra. Implementing these methods, we find $2,268$ explicit Swiss cheese manifolds, over half of which have $h^{1,1}=6$. Many of our solutions have multiple large cycles. Such Swiss cheese geometries facilitate moduli stabilization in string compactifications and provide flat directions for cosmological inflation.

    ↳ hep-thhep-phPRD(2018)·17 citations
18. 18*

    Phantom Domain Walls

    P. P. Avelino🇵🇹 · V. M. C. Ferreira🇵🇹 · J. Menezes🇧🇷 · L. Sousa🇵🇹

    We consider a model with two real scalar fields which admits phantom domain wall solutions. We investigate the structure and evolution of these phantom domain walls in an expanding homogeneous and isotropic universe. In particular, we show that the increase of the tension of the domain walls with cosmic time, associated to the evolution of the phantom scalar field, is responsible for an additional damping term in their equations of motion. We describe the macroscopic dynamics of phantom domain walls, showing that extended phantom defects whose tension varies on a cosmological timescale cannot be the dark energy.

    ↳ gr-qcastro-ph.COhep-phhep-thPRD(2017)·3 citations
19. 19*

    Signals of HE atmospheric muon decay in flight around the Sun's albedo versus astrophysical muon and tau neutrino traces in the Moon's shadow

    Daniele Fargion🇮🇹 · Pietro Oliva🇮🇹 · Pier Giorgio De Sanctis Lucentini🇷🇺 · Maxim Yu. Khlopov🇷🇺

    The Sun albedo of cosmic rays at GeVs energy has been discovered recently by FERMI satellite. They are traces of atmospheric CR hitting solar atmosphere and reflecting skimming gamma photons. Even if relevant for astrophysics, as being trace of atmospheric solar Cosmic Ray noises they cannot offer any signal of neutrino astronomy. On the contrary the Moon, with no atmosphere, may become soon a novel filtering calorimeter and an amplifier of energetic muon astronomical neutrinos (at TeV up to hundred TeV energy); these lepton tracks leave an imprint in their beta decay while in flight to Earth. Their TeV electron air-shower are among the main signals. Also a more energetic, but more rare, PeV up to EeV tau lunar neutrino events may be escaping as a tau lepton from the Moon: PeVs secondaries may be shining on Earth atmosphere in lunar shadows in a surprising rich way. One or a few gamma air-shower event inside the Moon shadows may occur each year in near future CTA or LHAASO TeVs gamma array detector, assuming a non negligible astrophysical TeV up to hundred TeV neutrino component (respect to our terrestrial ruling atmospheric ones); these signals will open a new wonderful passepartout keyhole for neutrino been seen along the Moon. The lunar solid angle is small and the muon or tau expected rate is rare, but future largest tau radio array as GRAND one might well discover such neutrino imprint.

    ↳ astro-ph.HEastro-ph.IMastro-ph.SRhep-phInt.J.Mod.Phys.D(2018)·5 citations
20. 20*

    Inflationary Features and Shifts in Cosmological Parameters from Planck 2015 Data

    Georges Obied🇺🇸 · Cora Dvorkin🇺🇸 · Chen Heinrich🇺🇸 · Wayne Hu🇺🇸 · V Miranda🇺🇸

    We explore the relationship between features in the Planck 2015 temperature and polarization data, shifts in the cosmological parameters, and features from inflation. Residuals in the temperature data at low multipole $\ell$, which are responsible for the high $H_0\approx 70$ km s${}^{-1}$Mpc${}^{-1}$ and low ${\sigma }_8{\Omega }_m^{1/2}$ values from $\ell <1000$ in power-law $\Lambda$CDM models, are better fit to inflationary features with a $1.9\sigma$ preference for running of the running of the tilt or a stronger $99\%$ CL local significance preference for a sharp drop in power around $k=0.004$ Mpc${}^{-1}$ in generalized slow roll and a lower $H_0\approx 67$ km s${}^{-1}$Mpc${}^{-1}$. The same in-phase acoustic residuals at $\ell >1000$ that drive the global $H_0$ constraints and appear as a lensing anomaly also favor running parameters which allow even lower $H_0$, but not once lensing reconstruction is considered. Polarization spectra are intrinsically highly sensitive to these parameter shifts, and even more so in the Planck 2015 TE data due to an outlier at $\ell \approx 165$, which disfavors the best fit $H_0$ $\Lambda$CDM solution by more than $2\sigma$, and high $H_0$ value at almost $3\sigma$. Current polarization data also slightly enhance the significance of a sharp suppression of large-scale power but leave room for large improvements in the future with cosmic variance limited $E$-mode measurements.

    ↳ astro-ph.COhep-phPRD(2017)·34 citations
21. 21*

    Small dark energy without small parameters

    Benjamin Shlaer🇳🇿

    We present a prototype model that resolves the cosmological constant problem using matter alone, i.e., without modifying gravity. Its generic cosmological solutions adjust an arbitrarily large, negative dark energy to a positive value parametrically suppressed by an initial field velocity. Inflationary initial conditions lead to a positive dark energy exponentially smaller in magnitude than any model parameter, or any scale in the initial conditions.

    ↳ hep-thastro-ph.COgr-qchep-ph2 citations
22. 22*

    Chiral response in lattice models of Weyl materials

    E. V. Gorbar🇺🇦 · V. A. Miransky🇨🇦 · I. A. Shovkovy🇺🇸 · P. O. Sukhachov🇨🇦

    For a generic lattice Hamiltonian of the electron states in Weyl materials, we calculate analytically the chiral (or, equivalently, valley) charge and current densities in the first order in background electromagnetic and strain-induced pseudoelectromagnetic fields. We find that the chiral response induced by the pseudoelectromagnetic fields is not topologically protected. Although our calculations reproduce qualitatively the anomalous chiral Hall effect, the actual result for the conductivity depends on the definition of the chirality as well as on the parameters of the lattice model. In addition, while for the well- separated Fermi surfaces surrounding the individual Weyl nodes the current induced by the magnetic field coincides almost exactly with the current of the chiral separation effect in linearized models, there are clear deviations when the Fermi surfaces undergo the Lifshitz transition. In general, we find that all chiral response coefficients vanish at large chemical potential.

    ↳ cond-mat.mes-hallhep-phPRB(2017)·11 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.