Mon·May 8, 2017Monday·May 8, 2017

1. 01*

   Yet Another Introduction to Dark Matter

   Martin Bauer🇩🇪 · Tilman Plehn🇩🇪

   Dark matter is, arguably, the most widely discussed topic in contemporary particle physics. Written in the language of particle physics and quantum field theory, these notes focus on a set of standard calculations needed to understand different dark matter candidates. After introducing some general features of such dark matter agents, we introduce a set of established models which guide us through four experimental aspects: the dark matter relic density extracted from the cosmic microwave background, indirect detection including the Fermi galactic center excess, direct detection, and collider searches.

   hep-phLect.Notes Phys.(2019)·146 citations
2. 02*

   Trimaximal $\mu$-$\tau$ reflection symmetry

   Werner Rodejohann🇩🇪 · Xun-Jie Xu🇩🇪

   The $\mu$-$\tau$ reflection symmetry $({\nu }_e,{\nu }_{\mu },{\nu }_{\tau })\to ({\overline{\nu }}_e,{\overline{\nu }}_{\tau },{\overline{\nu }}_{\mu })$ and the TM1 mixing (a PMNS matrix with the first column fixed to the TBM form) are both well compatible with experiments. If both approaches are simultaneously assumed, all lepton mixing parameters except for ${\theta }_{13}$ are predicted. In particular, one expects maximal CP violation ($|\delta |=90^{\circ }$), maximal atmospheric mixing (${\theta }_{23}=45^{\circ }$), a slightly less-than-TBM solar mixing angle (${\theta }_{12}\approx 34^{\circ }$), as well as values of $0$ or $\pi$ for the two Majorana phases. We study the renormalization stability of this highly predictive framework when neutrino mass is described by an effective Weinberg operator and by the type I seesaw mechanism, both in the Standard Model and with supersymmetry.

   hep-phhep-exPRD(2017)·64 citations
3. 03*

   Unified Dark Matter from a Simple Gauge Group on a Domain-Wall Brane

   Benjamin D. Callen🇦🇺

   Some models of asymmetric dark matter commonly employ a gauge group structure of the form $G_V\times G_D$ where $G_V$ is the visible gauge group containing the Standard Model and $G_D$ is the gauge group responsible for self-interactions amongst components of dark matter. In some models, there is also an additional spontaneously broken $U(1)$ gauge symmetry coupling the visible and dark sectors at high energies. One theoretical problem is how to unify the visible and dark sectors by inducing the spontaneous breaking $G\to G_V\times G_D$ for some large gauge group $G$. In this paper, we discuss how to generate such a structure at low energies, in the context of 4+1-dimensional domain-wall brane model, by employing a generalization of the Dvali-Shifman mechanism, used to localized gauge bosons on domain walls, called the clash-of-symmetries mechanism. In one model, we describe a clash-of-symmetries domain wall solution in a theory with two scalar fields in the adjoint representation which breaks the group $SU(12)$ to two differently embedded copies of $SU(6)\times SU(6)\times U(1)$, leading to a an effective $SU(5{)}_V\times SU(5{)}_D\times U(1{)}_X$-invariant field theory on the wall. We find that fermions in the mixed representations of $SU(5{)}_V\times SU(5{)}_D$ do not couple to the domain wall and thus remain 5D vector-like Dirac fermions, attaining masses of order $M_{GUT}$ when we perform the breaking $SU(5{)}_V\to SU(3{)}_c\times SU(2{)}_I\times U(1{)}_Y$, thus being removed from the spectrum. We also outline how to build a few alternative models, one based on the group $SU(9)$, and a couple more based on non-clash-of-symmetries domain wall solutions in $SU(12)$ and $SU(10)$ models.

   hep-ph1 citation
4. 04*

   Characterizing Higgs portal dark matter models at the ILC

   Teruki Kamon🇺🇸 · P. Ko🇰🇷 · Jinmian Li🇰🇷

   We study the Dark Matter (DM) discovery prospect and its spin discrimination in the theoretical framework of gauge invariant and renormalizable Higgs portal DM models at the ILC with $\sqrt{s}=500$ GeV. In such models, the DM pair is produced in association with a $Z$ boson. In case the singlet scalar DM, the mediator is just the SM Higgs boson, whereas for the fermion or vector DM there is an additional singlet scalar mediator that mixes with the SM Higgs boson, which produces significant observable differences. After careful investigation of the signal and backgrounds both at parton level and at detector level, we find the signal with hadronically decaying $Z$ boson provides a better search sensitivity than the signal with leptonically decaying $Z$ boson. Taking the fermion DM model as a benchmark scenario, when the DM-mediator coupling $g_{\chi }$ is relatively small, the DM signals are discoverable only for benchmark points with relatively light scalar mediator $H_2$. And the spin discriminating from scalar DM is always promising while it is difficult to discriminate from vector DM. As for $g_{\chi }$ approaching the perturbative limit, benchmark points with the mediator $H_2$ in the full mass region of interest are discoverable. And the spin discriminating from both the scalar and fermion DM are quite promising.

   hep-phhep-exEPJC(2017)·36 citations
5. 05*

   Meson Physics in Asymmetric Matter

   Andrea Mammarella

   This paper describes dynamic and thermodynamic (at $T=0$) properties of mesons in asymmetric matter in the framework of Chiral Perturbation Theory. We consider a mesonic system at vanishing temperature with nonzero isospin chemical potential and strangeness chemical potential and we study their effect on the phase diagram. We also study meson masses and mixing in the resulting normal phase, pion condensation phase and kaon condensation phase. We find differences with previous papers regarding meson masses and mixing in the condensed phases; the results presented here are supported by theory group analysis and direct calculations. Pressure, density and equation of state of the system at $T=0$ and nonzero ${\mu }_I$ are calculated, finding remarkable agreement with analogue studies performed by lattice calculations.

   hep-phJ.Phys.Conf.Ser.(2017)·1 citation
6. 06*

   Hiding an elephant: heavy sterile neutrino with large mixing angle does not contradict cosmology

   F. Bezrukov🇬🇧 · A. Chudaykin🇷🇺 · D. Gorbunov🇷🇺

   We study a model of a keV-scale sterile neutrino with a relatively large mixing with the Standard Model sector. Usual considerations predict active generation of such particles in the early Universe, which leads to constraints from the total Dark Matter density and absence of X-ray signal from sterile neutrino decay. These bounds together may deem any attempt of creation of the keV scale sterile neutrino in the laboratory unfeasible. We argue that for models with a hidden sector coupled to the sterile neutrino these bounds can be evaded, opening new perspectives for the direct studies at neutrino experiments such as Troitsk $\nu$-mass and KATRIN. We estimate the generation of sterile neutrinos in scenarios with the hidden sector dynamics keeping the sterile neutrinos either massless or superheavy in the early Universe. In both cases the generation by oscillations from active neutrinos in plasma is suppressed.

   hep-phastro-ph.COhep-exJCAP(2017)·45 citations
7. 07*

   One-loop renormalisation of the NMSSM in SloopS 2: the Higgs sector

   G. Bélanger🇫🇷 · V. Bizouard🇫🇷 · F. Boudjema🇫🇷 · G. Chalons🇫🇷

   We present a full one-loop renormalisation of the Higgs sector of the Next-to-Minimal- Supersymmetric-Standard-Model (NMSSM) and its implementation within SloopS, a code for the automated computations of one-loop processes in theories beyond the Stan- dard Model. The present work is the sequel to the study we performed on the renor- malisation of the sectors of the NMSSM comprising neutralinos, charginos and sfermions thereby completing the full one-loop renormalisation of the NMSSM. We have investi- gated several renormalisation schemes based on alternative choices (on-shell or DR) of the physical parameters. Special attention is paid to the issue of the mixing between physical fields. To weigh the impact of the different renormalisation schemes, the partial widths for the decays of the Higgs bosons into supersymmetric particles are computed at one-loop. In many decays large differences between the schemes are found. We discuss the origin of these differences. In particular we study two contrasting scenarios. The first model is MSSM-like with a small value for the mixing between the doublet and sin- glet Higgs superfields while the second model has a moderate value for this mixing. We critically discuss the issue of the reconstruction of the underlying parameters and their counterterms in the case of a theory with a large number of parameters, such as the NMSSM, from a set of physical parameters. In the present study this set corresponds to the minimum set of masses for the implementation of the on-shell schemes.

   hep-phhep-thPRD(2017)·25 citations
8. 08*

   Single-diffractive production of dijets within the $k_t$-factorization approach

   Marta Luszczak🇵🇱 · Rafal Maciula🇵🇱 · Antoni Szczurek🇵🇱 · Izabela Babiarz🇵🇱

   We discuss single-diffractive production of dijets. The cross section is calculated within the resolved pomeron picture, for the first time in the $k_t$-factorization approach, neglecting transverse momentum of the pomeron. We use Kimber-Martin-Ryskin unintegrated parton (gluon, quark, antiquark) distributions (UPDF) both in the proton as well as in the pomeron or subleading reggeon. The UPDFs are calculated based on conventional MMHT2014nlo PDFs in the proton and H1 collaboration diffractive PDFs used previously in the analysis of diffractive structure function and dijets at HERA. For comparison we present results of calculations performed within collinear-factorization approach. Our results remaind those obtained in the NLO approach. The calculation is (must be) supplemented by the so-called gap survival factor which may, in general, depend on kinematical variables. We try to describe the existing data from Tevatron and make detailed predictions for possible LHC measurements. Several differential distributions are calculated. The ${\overline{E}}_T$, $\overline{\eta }$ and $x_{\bar{p}}$ distributions are compared with the Tevatron data. A reasonable agreement is obtained for the first two distributions. The last one requires to introduce a gap survival factor which depends on kinematical variables. We discuss how the phenomenological dependence on one kinematical variable may influence dependence on other variables such as ${\overline{E}}_T$ and $\overline{\eta }$. Several distributions for the LHC are shown.

   hep-phPRD(2017)·3 citations
9. 09*

   New Physics effects in charm meson decays involving $c\to u{l}^{+}{l}^{-}(l_i^{\mp }{l}_j^{\pm })$ transitions

   Suchismita Sahoo🇮🇳 · Rukmani Mohanta🇮🇳

   We study the effect of scalar leptoquark and $Z^{\prime }$ boson on the rare decays of $D$ mesons involving flavour changing transitions $c\to u{l}^{+}{l}^{-}(l_i^{\mp }{l}_j^{\pm })$. We constrain the new physics parameter space using the branching ratio of the rare decay mode $D^0\to {\mu }^{+}{\mu }^{-}$ and the $D^0-{\bar{D}}^0$ oscillation data. We compute the branching ratios, forward-backward asymmetry parameters and flat terms in $D^{+(0)}\to {\pi }^{+(0)}{\mu }^{+}{\mu }^{-}$ processes using the constrained parameters. The branching ratios of the lepton flavour violating $D$ meson decays, such as $D^0\to \mu e,\tau e$ and $D^{+(0)}\to {\pi }^{+(0)}{\mu }^{-}{e}^{+}$ are also investigated.

   hep-phEPJC(2017)·26 citations
10. 10*

    Global view on coupled dynamics of heavy and light flavor observables from EPOSHQ

    Pol Bernard Gossiaux🇫🇷 · Joerg Aichelin🇫🇷 · Marlene Nahrgang🇫🇷 · Vitalii Ozvenchuk🇵🇱 · Klaus Werner🇫🇷

    We present an analysis of the comparison between 2nd and 3rd flow harmonics of $\pi$, protons and D mesons produced in ultrarelativistic heavy ion collisions. We advocate that such an analysis could turn out to be a good strategy in order to quantify the off-equilibrium dynamics of heavy flavor at lower transverse momentum $p_T$.

    hep-phnucl-thNPA(2017)·6 citations
11. 11*

    Cornering pseudoscalar-mediated dark matter with the LHC and cosmology

    Shankha Banerjee🇫🇷 · Daniele Barducci🇮🇹 · Geneviève Bélanger🇫🇷 · Benjamin Fuks🇫🇷 · Andreas Goudelis🇫🇷 · Bryan Zaldivar🇫🇷

    Models in which dark matter particles communicate with the visible sector through a pseudoscalar mediator are well-motivated both from a theoretical and from a phenomenological standpoint. With direct detection bounds being typically subleading in such scenarios, the main constraints stem either from collider searches for dark matter, or from indirect detection experiments. However, LHC searches for the mediator particles themselves can not only compete with -- or even supersede -- the reach of direct collider dark matter probes, but they can also test scenarios in which traditional monojet searches become irrelevant, especially when the mediator cannot decay on-shell into dark matter particles or its decay is suppressed. In this work we perform a detailed analysis of a pseudoscalar-mediated dark matter simplified model, taking into account a large set of collider constraints and concentrating on the parameter space regions favoured by cosmological and astrophysical data. We find that mediator masses above 100-200~GeV are essentially excluded by LHC searches in the case of large couplings to the top quark, while forthcoming collider and astrophysical measurements will further constrain the available parameter space.

    hep-phJHEP(2017)·48 citations
12. 12*

    GPS and the Search for Axions

    A. Nicolaidis🇬🇷

    GPS, an excellent tool for geodesy, may serve also particle physics. In the presence of Earth's magnetic field, a GPS photon may be transformed into an axion. The proposed experimental setup involves the transmission of a GPS signal from a satellite to another satellite, both in low orbit around the Earth. To increase the accuracy of the experiment, we evaluate the influence of Earth's gravitational field on the whole quantum phenomenon. There is a significant advantage in our proposal. While geomagnetic field B is low, the magnetized length L is very large, resulting into a scale (BL)^2 orders of magnitude higher than existing or proposed reaches. The transformation of the GPS photons into axion particles will result in a dimming of the photons and even to a "light shining through the Earth" phenomenon.

    hep-phgr-qchep-exJ.Mod.Phys.(2017)·2 citations
13. 13*

    Estimate of a non-helical electroweak primordial bootstrap field today

    Poul Olesen🇩🇰

    We estimate the magnitude today of the primordial magnetic field originating at the electroweak phase transition. We find that the field, which at the electroweak phase transition is originally of order $10^{23}-10^{24}$ G correlated over the Hubble scale, today is of order $10^{-14}$ G at a scale of order 2 kpc. This result is consistent with the lower limit on the strength of intergalactic magnetic fields obtained by Neronov and Vovk from observations of TeV blazars. The field is non-helical. We compare our results with the helical case discussed by Field and Carroll.

    ↳ astro-ph.COhep-phhep-th1 citation
14. 14*

    Experimental results on event shapes at hadron colliders

    Antonio Ortiz🇲🇽

    In this paper a review on event shapes at hadron colliders, mainly focused on experimental results, is presented. Measurements performed at the Tevatron and at the LHC, for the soft and hard regimes of QCD, are reviewed. The potential applications of event shapes for unveiling the origin of collective-like phenomena in small collision systems as well as for testing pQCD predictions are discussed.

    ↳ hep-exhep-phAdv.Ser.Direct.High Energy Phys.(2018)·29 citations
15. 15*

    New asymptotic Anti-de Sitter solution with a timelike extra dimension in 5D relativity

    Molin Liu🇨🇳 · Yingying Shi🇨🇳 · Zonghua Zhao🇨🇳 · Yu Han🇨🇳

    In 5D relativity, the usual 4D cosmological constant is determined by the extra dimension. If the extra dimension is spacelike, one can get a positive cosmological constant $\Lambda$ and a 4D de Sitter (dS) space. In this paper we present that, if the extra dimension is timelike oppositely, the negative $\Lambda$ will be emerged and the induced 4D space will be an asymptotic Anti-de Sitter (AdS). Under the minimum assumption, we solve the Kaluza-Klein equation $R_{AB}=0$ in a canonical system and obtain the AdS solution in a general case. The result shows that an AdS space is induced naturally from a Kaluza-Klein manifold on a hypersurface (brane). The Lagrangian of test particle indicates the equation of motion can be geodesics if the 4D metric is independent of extra dimension. The causality is well respected because it is appropriately defined by a null higher dimensional interval. In this 5D relativity, the holographic principle can be used safely because the brane is asymptotic Euclidean AdS in the bulk. We also explore some possible holographic duality implications about the field/operator correspondence and the two-points correlation functions.

    ↳ gr-qchep-phhep-thAnnals Phys.(2017)·0 citations
16. 16*

    Diffuse neutrinos from luminous and dark supernovae: prospects for upcoming detectors at the O(10) kt scale

    Alankrita Priya🇺🇸 · Cecilia Lunardini🇺🇸

    We estimate the Diffuse Supernova Neutrino Background (DSNB) using the simulation results for neutron star-forming and black hole-forming stellar collapses from the Garching group. Scenarios with different distributions of black-hole forming collapses with the progenitor mass are discussed, and the uncertainty on the cosmological rate of collapses is included. The electron antineutrino component of the DSNB above 11 MeV of energy is found to be ~(1.4 - 3.7) cm^-2 s^-1; the contribution of black hole-forming collapses could dominate the flux above ~25 MeV. We calculate the potential of detecting the DSNB at SuperK-Gd and JUNO, in about a decade-long period of operation. We find that, in our model, it is likely that a significant excess above the background will be obtained at JUNO, while detection will be more difficult at SuperK-Gd. The potential when the two experimental results are examined jointly is discussed as well. We also consider an example of a future O(10) kt slow liquid scintillator detector, and show that there the odds of detection are very good. Our results motivate experimental efforts in reducing the backgrounds due to neutral current scattering of atmospheric neutrinos in SuperK-Gd.

    ↳ astro-ph.HEastro-ph.SRhep-exhep-phJCAP(2017)·60 citations
17. 17*

    Fermi points and the Nambu sum rule in the polar phase of ${}^3$He

    M.A. Zubkov🇷🇺

    We discuss the polar phase of ${}^3$He, which is realized in the anisotropic aerogel. We consider it in the framework of the BCS model. In the absence of the spin - orbit interaction this model predicts the appearance of the Fermi line. However, it is topologically unstable. We demonstrate, that the spin - orbit interaction gives rise to the appearance of the two Fermi points instead of the Fermi line. In addition to the gapless Nambu - Goldstone bosons in this system the collective gapped bosonic states exist. Their gaps are calculated, and the corresponding Nambu sum rule is established.

    ↳ cond-mat.mes-hallhep-phJETP Lett.(2017)·2 citations
18. 18*

    Collapse threshold for a cosmological Klein Gordon field

    Juan Carlos Hidalgo🇲🇽 · Josue De-Santiago🇲🇽 · Gabriel German🇲🇽 · Nandinii Barbosa-Cendejas🇲🇽 · Waldemar Ruiz-Luna🇲🇽

    Oscillating scalar fields are useful to model a variety of matter components in the universe. One or more scalar fields participate in the reheating process after inflation, while at much lower energies scalar fields are robust dark matter candidates. Pertaining structure formation in these models, it is well known that inhomogeneities of the Klein-Gordon field are unstable above the characteristic De Broglie wavelength. In this paper we show that such instability implies the existence of a threshold amplitude for the collapse of primordial fluctuations. We use this threshold to correctly predict the cut--off scale of the matter power spectrum in the scalar field dark matter model. Furthermore, for a Klein-Gordon field during reheating we show that this same threshold allows for abundant production of structure (oscillons but not necessarily black holes). Looking at the production of Primordial Black Holes (PBHs) in this scenario we note that the sphericity condition yields a much lower probability of PBH formation at the end of inflation. Remarkably, even after meeting such stringent condition, we find that PBHs may be overproduced during reheating. We finally constrain the epochs at which an oscillating Klein-Gordon field could dominate the early universe.

    ↳ astro-ph.COgr-qchep-phPRD(2017)·34 citations
19. 19*

    Viability of quantum-gravity induced ultraviolet completions for matter

    Astrid Eichhorn🇩🇪 · Aaron Held🇩🇪

    We highlight how the existence of an ultraviolet completion for interacting Standard-Model type matter puts constraints on the viable microscopic dynamics of asymptotically safe quantum gravity within truncated Renormalization Group flows. A first constraint -- the weak-gravity bound -- is rooted in the destruction of quantum scale-invariance in the matter system by strong quantum-gravity fluctuations. A second constraint arises by linking Planck-scale dynamics to the dynamics at the electroweak scale. Specifically, we delineate how to extract a prediction of the top quark mass from asymptotically safe gravity and stress that a finite top mass could be difficult to accommodate in a significant part of the gravitational coupling space.

    ↳ gr-qchep-phhep-thPRD(2017)·142 citations
20. 20*

    Modification of Schrödinger-Newton equation due to braneworld models with minimal length

    Anha Bhat🇮🇳 · Sanjib Dey🇫🇷 · Mir Faizal🇨🇦 · Chenguang Hou🇸🇬 · Qin Zhao🇸🇬

    We study the correction of the energy spectrum of a gravitational quantum well due to the combined effect of the braneworld model with infinite extra dimensions and generalized uncertainty principle. The correction terms arise from a natural deformation of a semiclassical theory of quantum gravity governed by the Schrödinger-Newton equation based on a minimal length framework. The two fold correction in the energy yields new values of the spectrum, which are closer to the values obtained in the GRANIT experiment. This raises the possibility that the combined theory of the semiclassical quantum gravity and the generalized uncertainty principle may provide an intermediate theory between the semiclassical and the full theory of quantum gravity. We also prepare a schematic experimental set-up which may guide to the understanding of the phenomena in the laboratory.

    ↳ hep-thhep-phquant-phPLB(2017)·21 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.