Fri·Sep 21, 2018Friday·September 21, 2018

1. 01*

   Phenomenology of the inflation-inspired NMSSM at the electroweak scale

   Wolfgang Gregor Hollik🇩🇪 · Stefan Liebler🇩🇪 · Gudrid Moortgat-Pick🇩🇪 · Sebastian Paßehr🇫🇷 · Georg Weiglein🇩🇪

   The concept of Higgs inflation can be elegantly incorporated in the Next-to-Minimal Supersymmetric Standard Model (NMSSM). A linear combination of the two Higgs-doublet fields plays the role of the inflaton which is non-minimally coupled to gravity. This non-minimal coupling appears in the low-energy effective superpotential and changes the phenomenology at the electroweak scale. While the field content of the inflation-inspired model is the same as in the NMSSM, there is another contribution to the $\mu$ term in addition to the vacuum expectation value of the singlet. We explore this extended parameter space and point out scenarios with phenomenological differences compared to the pure NMSSM. A special focus is set on the electroweak vacuum stability and the parameter dependence of the Higgs and neutralino sectors. We highlight regions which yield a SM-like $125$GeV Higgs boson compatible with the experimental observations and are in accordance with the limits from searches for additional Higgs bosons. Finally, we study the impact of the non-minimal coupling to gravity on the Higgs mixing and in turn on the decays of the Higgs bosons in this model.

   hep-phEPJC(2019)·48 citations
2. 02*

   Bulk observables in the LHC 5.02 TeV Pb+Pb collisions within the integrated HydroKinetic Model

   V. M. Shapoval🇺🇦 · Yu. M. Sinyukov🇺🇦

   The paper is devoted to the description and prediction of various bulk observables in the Pb+Pb collisions at the LHC energy $\sqrt{s_{NN}}=5.02$ TeV within the integrated hydrokinetic model (iHKM). Sensitivity of the results to the choice of the appropriate model parameter values is also investigated. It is found that changing of the relaxation time and the rate of thermalization, which characterize the pre-thermal stage of the matter evolution, as well as switching to another equation of state at the hydrodynamic stage and the corresponding hadronization temperature, does not destroy the results, if simultaneously one provides an appropriate adjusting of the initial time for the superdense matter formation and related maximal initial energy density.

   hep-phnucl-exnucl-thPRC(2019)·17 citations
3. 03*

   The Role of Mesons in Muon g-2

   Fred Jegerlehner🇩🇪

   The muon anomaly $a_{\mu }=(g_{\mu }-2)/2$ showing a persisting 3 to 4 $\sigma$ deviation between the SM prediction and the experiment is one of the most promising signals for physics beyond the SM. As is well known, the hadronic uncertainties are limiting the accuracy of the Standard Model prediction. Therefore a big effort is going on to improve the evaluations of hadronic effects in order to keep up with the 4-fold improved precision expected from the new Fermilab measurement in the near future. A novel complementary type experiment planned at J-PARC in Japan, operating with ultra cold muons, is expected to be able to achieve the same accuracy but with completely different systematics. So exciting times in searching for New Physics are under way. I discuss the role of meson physics in calculations of the hadronic part of the muon g-2. The improvement is expected to substantiate the present deviation $\Delta a_{\mu }^{\mathrm{New}\mathrm{Physics}}=\Delta a_{\mu }^{\mathrm{Experiment}}-\Delta a_{\mu }^{\mathrm{Standard}\mathrm{Model}}$ to a 6 to 10 standard deviation effect, provided hadronic uncertainties can be reduce by a factor two. This concerns the hadronic vacuum polarization as well as the hadronic light-by-light scattering contributions, both to a large extent determined by the low lying meson spectrum. Better meson production data and progress in modeling meson form factors could greatly help to improve the precision and reliability of the SM prediction of $a_{\mu }$ and thereby provide more information on what is missing in the SM.

   hep-phEPJ Web Conf.(2019)·18 citations
4. 04*

   Multipartite Dark Matter with Scalars, Fermions and signatures at LHC

   Subhaditya Bhattacharya🇮🇳 · Purusottam Ghosh🇮🇳 · Narendra Sahu🇮🇳

   Basic idea of this analysis is to achieve a two-component dark matter (DM) framework composed of a scalar and a fermion, with non-negligible DM-DM interaction contributing to thermal freeze out (hence relic density), but hiding them from direct detection bounds. We therefore augment the Standard Model (SM) with a scalar singlet ($S$) and three vectorlike fermions: two singlets (${\chi }_1,{\chi }_2$) and a doublet ($N$). Stability of the two DM components is achieved by a discrete ${\mathcal{Z}}_2\times {{\mathcal{Z}}^{\prime }}_2$ symmetry, under which the additional fields transform suitably. Fermion fields having same ${\mathcal{Z}}_2\times {{\mathcal{Z}}^{\prime }}_2$ charge ($N,{\chi }_1$ in the model) mix after electroweak symmetry breaking (EWSB) and the lightest component becomes one of the DM candidates, while scalar singlet $S$ is the other DM component connected to visible sector by Higgs portal coupling. The heavy fermion (${\chi }_2$) plays the role of mediator to connect the two DM candidates through Yukawa interaction. This opens up a large parameter space for the heavier DM component through DM-DM conversion. Hadronically quiet dilepton signature, arising from the fermion dark sector, can be observed at Large Hadron Collider (LHC) aided by the presence of a lighter scalar DM component, satisfying relic density and direct search bounds through DM-DM conversion.

   hep-phJHEP(2019)·65 citations
5. 05*

   New narrow nucleon resonances $N^{\ast }(1685)$ and $N^{\ast }(1726)$ within the chiral quark-soliton model

   Ghil-Seok Yang🇰🇷 · Hyun-Chul Kim🇰🇷

   We investigate the strong and radiative decay widths of the narrow nucleon resonances $N^{\ast }(1685)$ and $N^{\ast }(1726)$ within the framework of the SU(3) chiral quark-soliton model. All the relevant parameters are taken from those used to describe the properties of the baryon octet and decuplet in previous works. The masses of the antidecuplet nucleon and the eikosiheptaplet (27-plet) nucleon with spin 3/2 are determined respectively to be $(1690.2\pm 10.5)\mathrm{MeV}$ and $(1719.6\pm 7.4)\mathrm{MeV}$. The decay width for $N^{\ast }(1685)\to \eta +N$ is found to be approximately three times larger than that for $N^{\ast }(1685)\to \pi +N$. The width of the decay $N^{\ast }\left(1726\right)3/2^{+}\to \eta +N$ is even about 31 times larger than that of $N^{\ast }\left(1726\right)3/2^{+}\to \pi +N$. The ratio of the radiative decays for $N^{\ast }(1685)$ is obtained to be ${\Gamma }_{n{n}^{\ast }(1685)}/{\Gamma }_{p{p}^{\ast }(1685)}=8.62\pm 3.45$ which explains very well the neutron anomaly. In contrast, we find ${\Gamma }_{p{p}^{\ast }(1726)}/{\Gamma }_{n{n}^{\ast }(1726)}=3.72\pm 0.64$, which indicates that the production of $N^{\ast }(1726)$ is more likely to be observed in the proton channel. We also examined the decay modes of these narrow nucleon resonances with the strangeness hadrons involved.

   hep-phnucl-exnucl-thPTEP(2019)·6 citations
6. 06*

   A chiral SU(4) explanation of the $b\to s$ anomalies

   Shyam Balaji🇦🇺 · Robert Foot🇦🇺 · Michael A. Schmidt🇦🇺

   We propose a variant of the Pati-Salam model, with gauge group $SU(4{)}_C\times SU(2{)}_L\times U(1{)}_{Y^{\prime }}$, in which the chiral left-handed quarks and leptons are unified into a $\underline{4}$ of $SU(4{)}_C$, while the right-handed quarks and leptons have quite a distinct treatment. The $SU(4{)}_C$ leptoquark gauge bosons can explain the measured deviation of lepton flavour universality in the rare decays: $\bar{B}\to {\bar{K}}^{(\ast )}\bar{\ell }\ell ,\ell =\mu ,e$ (taken as a hint of new physics). The model satisfies the relevant experimental constraints and makes predictions for the important $B$ and $\tau$ decays. These predictions will be tested at the LHCb and Belle II experiments when increased statistics become available.

   hep-phPRD(2019)·46 citations
7. 07*

   Pion constituent quarks couplings strong form factors: a dynamical approach

   Fabio L. Braghin🇧🇷

   Form factors for pions interactions with constituent quarks are investigated as the leading effective couplings obtained from a one loop background field method applied to a global color model. Two pion field definitions are considered and the resulting eleven form factors are expressed in terms of components of the quark and gluon propagators that compose only two momentum dependent functions. A momentum dependent Goldberger Treiman relation is also obtained as one of the ratios between the form factors. The resulting form factors with pion momenta up to 1.5 GeV are exhibited for different quark effective masses and two different non-perturbative gluon propagators and they present similar behavior to fittings of experimental data from nucleons form factors. The corresponding pseudoscalar averaged quadratic radii (a.q.r.) and correction to the axial a.q.r. are presented as functions of the sea quark effective mass, being equal respectively to the scalar and vector ones at the present level of calculation.

   hep-phnucl-thPRD(2019)·12 citations
8. 08*

   The quark spectral functions and the Hadron Vacuum Polarization from application of DSEs in Minkowski space

   Vladimir Sauli🇨🇿

   The hadronic vacuum polarization function ${\Pi }_h$ for two light flavors is computed on the entire domain of spacelike and timelike momenta using a framework of Dyson-Schwinger equations. The analytical continuation of the function ${\Pi }_h$ is based on the utilization of the Gauge Technique with the entry of QCD Green's functions determined from generalized quark spectral functions. For the first time, the light quark spectral functions are extracted from the solution of the gap equation for the quark propagator. The scale is set up by the phenomena of dynamical chiral symmetry breaking, which is a striking feature of low energy QCD.

   hep-phFew Body Syst.(2020)·9 citations
9. 09*

   Total and differential cross sections for Higgs and top-quark production

   Nikolaos Kidonakis🇺🇸

   I present theoretical calculations for Higgs-boson and top-quark production, including high-order soft-gluon corrections. I discuss charged-Higgs production in association with a top quark or a $W$ boson, as well as single-top and top-antitop production. Total cross sections as well as transverse-momentum and rapidity distributions of the top quark or the Higgs boson are presented for various LHC energies.

   hep-phUniverse(2018)·2 citations
10. 10*

    Benchmarking the Inert Doublet Model for e+ e- colliders

    Jan Kalinowski🇵🇱 · Wojciech Kotlarski🇩🇪 · Tania Robens🇭🇺 · Dorota Sokolowska🇵🇱 · Aleksander Filip Zarnecki🇵🇱

    We present benchmarks for the Inert Doublet Model, a Two Higgs Doublet Model with a dark matter candidate. They are consistent with current constraints on direct detection, including the most recent bounds from the XENON1T experiment and relic density of dark matter, as well as with known collider and low-energy limits. We focus on parameter choices that promise detectable signals at lepton colliders via pair-production of H+H- and HA. For these we choose a large variety of benchmark points with different kinematic features, leading to distinctly different final states in order to cover the large variety of collider signatures that can result from the model.

    hep-phJHEP(2018)·111 citations
11. 11*

    Glueballs and deconfinement temperature in AdS/QCD

    S.S. Afonin🇷🇺 · A.D. Katanaeva🇷🇺

    We put forward an alternative way to estimate the deconfinement temperature in bottom-up holographic models. The deconfinement in AdS/QCD is related to the Hawking-Page phase transition, in which the critical Hawking temperature is identified with the deconfinement one in the gauge theory. The numeric estimation of the latter is only possible when the parameters of a $5D$ dual model are previously determined from consistency with other physical aspects, standardly, providing a description of the QCD resonances. The traditional way to fix parameters in the simplest AdS/QCD models is to reproduce the mass of the $\rho$ meson or the slope of the approximate radial Regge trajectory of the $\rho$ excitations. Motivated by a general idea that the slope value originates in gluodynamics, we propose calculating the deconfinement temperature using the trajectory of scalar glueballs. We consider several holographic models and use the recent idea of isospectral potentials to make an additional check of the relevance of our approach. It is demonstrated that different models from an isospectral family (i.e. the models leading to identical predictions for spectrum of hadrons with fixed quantum numbers) result in different predictions for the deconfinement temperature. This difference is found to be quite small in the scalar glueball channel but very large in the vector meson channel. The observed stability in the former case clearly favours the choice of the glueball channel for thermodynamic predictions in AdS/QCD models. For a balanced approach, we argue that either assuming $f_0(1500)$ to have a dominating component of $0^{++}$ glueball or accepting the idea of the universality in the radial Regge trajectories of light non-strange vector mesons one can reproduce the results for the deconfinement temperature obtained before in the lattice simulations in the background of non-dynamical quarks.

    hep-phhep-thPRD(2018)·31 citations
12. 12*

    Recent Improvements for the Lepton Propagator PROPOSAL

    Mario Dunsch🇩🇪 · Jan Soedingrekso🇩🇪 · Alexander Sandrock🇩🇪 · Maximilian Meier🇩🇪 · Thorben Menne🇩🇪 · Wolfgang Rhode🇩🇪

    The lepton propagator PROPOSAL is a Monte-Carlo Simulation library written in C++, propagating high energy muons and other charged particles through large distances of media. In this article, a restructuring of the code is described, which yields a performance improvement of up to $30\%$. For an improved accuracy of the propagation processes, more exact calculations of the leptonic and hadronic decay process and more precise parametrizations for the interaction cross sections are now available. The new modular structure allows a more flexible and custom usage, which is further facilitated with a python interface.

    hep-phastro-ph.IMhep-exComput.Phys.Commun.(2019)·54 citations
13. 13*

    $\Xi (1690{)}^{-}$ production in the $K^{-}p\to K^{+}{K}^{-}\Lambda$ reaction process near threshold

    Jung Keun Ahn🇰🇷 · Seung-il Nam🇰🇷

    We investigate $\Xi (1690{)}^{-}$ production from the $K^{-}p\to K^{+}{K}^{-}\Lambda$ reaction within the effective Lagrangian approach at the tree-level Born approximation. We consider the $s$- and $u$-channel $\Sigma /\Lambda$ ground states and resonances for the $\Xi$-pole contributions, in addition to the $s$-channel $\Lambda$, $u$-channel nucleon pole, and $t$-channel $K^{-}$-exchange for the $\varphi$-pole contributions. The $\Xi$-pole includes $\Xi (1320)$, $\Xi (1535)$, $\Xi (1690)(J^p=1/2^{-})$,and $\Xi (1820)(J^p=3/2^{-})$. We calculate the Dalitz plot density of $(d^2\sigma /d{M}_{K^{+}{K}^{-}}d{M}_{K^{-}\Lambda }$ at 4.2 GeV$/c$) and the total cross sections for the $K^{-}p\to K^{+}{K}^{-}\Lambda$ reaction near the threshold. The calculation results are in good agreement with previously acquired experimental data. Using the parameters from the fit, we present the total and differential cross sections for the two-body $K^{-}p\to K^{+}\Xi (1690{)}^{-}$ reaction near the threshold. In our calculation, a strong enhancement at backward $K^{+}$ angles is predicted because of the dominant $u$-channel contribution. We also demonstrate that the Dalitz plot analysis for $p_{K^{-}}=1.915--2.065$ GeV/c enables us to access direct information regarding $\Xi (1690{)}^{-}$ production, which can be tested by future $K^{-}$ beam experiments. The possible spin-parity states of $\Xi (1690{)}^{-}$ are briefly discussed as well.

    hep-phhep-exnucl-thPRD(2018)·4 citations
14. 14*

    GeV-Scale Messengers of Planck-Scale Dark Matter

    Hooman Davoudiasl🇺🇸 · Gopolang Mohlabeng🇺🇸

    If dark matter (DM) originates from physics near the Planck scale it could be directly detected via its multiple scattering signals, yet this requires a large cross section for DM interactions with atoms. Hence, detection of such DM could imply mediation by new low mass messengers. We propose that a dark $U(1{)}_d$ remnant of the underlying spacetime geometry or a unified theory may survive down to small mass scales $\sim 1$ GeV, connecting low energy Standard Model (SM) and Planck scale phenomena. Typical required cross sections for direct detection of Planck scale DM can be achieved through the $U(1{)}_d$ interactions of DM with SM quarks. Low energy intense sources may uncover the GeV scale messengers of Planckian physics, allowing for testable predictions. We assume that $U(1{)}_d$ is gauged baryon number, which implies several new electroweak charged particles are expected to arise near the weak scale to cancel gauge anomalies. The model generically gives rise to kinetic mixing between the $U(1{)}_d$ gauge boson and the photon, which may be measurable. In this scenario, direct detection of DM and measurements of a low energy messenger, including its kinetic mixing with the photon, can potentially shed light on the high energy character of the scenario. Astrophysical considerations related to white dwarf stability against runaway nuclear fusion potentially disfavor DM heavier than $\sim 10^{17}$ GeV within our assumed messenger model.

    hep-phPRD(2018)·16 citations
15. 15*

    Holographic QCD in the Veneziano limit and neutron stars

    Niko Jokela🇫🇮 · Matti Jarvinen🇳🇱 · Jere Remes🇺🇸

    We use the holographic V-QCD models to analyse the physics of dense QCD and neutron stars. Accommodating lattice results for thermodynamics of QCD enables us to make generic predictions for the Equation of State (EoS) of the quark matter phase in the cold and dense regime. We demonstrate that the resulting pressure in V-QCD matches well with a family of neutron-star-matter EoSs that interpolate between state-of-the-art theoretical results for low and high density QCD. After implementing the astrophysical constraints, i.e., the largest known neutron star mass and the recent LIGO/Virgo results for the tidal deformability, we analyse the phase transition between the baryonic and quark matter phases. We find that the baryon density $n_B$ at the transition is at least 2.9 times the nuclear saturation density $n_s$. The transition is of strongly first order at low and intermediate densities, i.e., for $n_B/n_s\lesssim 7.5$.

    hep-phastro-ph.HEhep-thJHEP(2019)·88 citations
16. 16*

    Higgs mass and vacuum stability with high-scale supersymmetry

    Jae-hyeon Park🇰🇷

    In the high-scale (split) MSSM, the measured Higgs mass sets an upper bound on the supersymmetric scalar mass scale MSUSY around $10^{11}$ ($10^8$) GeV, for $\tan \beta$ in the standard range and the central value of the top quark mass $m_t$. This article discusses how maximal MSUSY is affected by negative threshold corrections to the quartic Higgs coupling arising from the sbottom and stop trilinear couplings. In the high-scale MSSM with very high $\tan \beta$, the electroweak vacuum decay due to the large bottom Yukawa coupling rules out the possibility of raising MSUSY beyond the above limit. In cases with large $A_b$ or $A_t$, MSUSY as a common mass of the extra fermions and scalars can be as high as $10^{17}$ GeV remaining consistent with $m_h$ and the vacuum longevity if $m_t$ is smaller than the central value by $2\sigma$. For the central value of $m_t$, the upper limit on MSUSY does not change very much owing to the metastability, which is the case also in the split MSSM even with $\pm 2\sigma$ variations in $m_t$.

    hep-ph4 citations
17. 17*

    Lifetimes of Doubly Charmed Baryons

    Hai-Yang Cheng🇹🇼 · Yan-Liang Shi🇹🇼

    The lifetimes of doubly charmed hadrons are analyzed within the framework of the heavy quark expansion (HQE). Lifetime differences arise from spectator effects such as $W$-exchange and Pauli interference. The ${\Xi }_{cc}^{++}$ baryon is longest-lived in the doubly charmed baryon system owing to the destructive Pauli interference absent in the ${\Xi }_{cc}^{+}$ and ${\Omega }_{cc}^{+}$. In the presence of dimension-7 contributions, its lifetime is reduced from $\sim 5.2\times 10^{-13}s$ to $\sim 3.0\times 10^{-13}s$. The ${\Xi }_{cc}^{+}$ baryon has the shortest lifetime of order $0.45\times 10^{-13}s$ due to a large contribution from the $W$-exchange box diagram. It is difficult to make a precise quantitative statement on the lifetime of ${\Omega }_{cc}^{+}$. Contrary to ${\Xi }_{cc}$ baryons, $\tau ({\Omega }_{cc}^{+})$ becomes longer in the presence of dimension-7 effects and the Pauli interference ${\Gamma }_{+}^{\mathrm{int}}$ even becomes negative. This implies that the subleading corrections are too large to justify the validity of the HQE. Demanding the rate ${\Gamma }_{+}^{\mathrm{int}}$ to be positive for a sensible HQE, we conjecture that the ${\Omega }_c^0$ lifetime lies in the range of $(0.75\sim 1.80)\times 10^{-13}s$. The lifetime hierarchy pattern is $\tau ({\Xi }_{cc}^{++})>\tau ({\Omega }_{cc}^{+})>\tau ({\Xi }_{cc}^{+})$ and the lifetime ratio $\tau ({\Xi }_{cc}^{++})/\tau ({\Xi }_{cc}^{+})$ is predicted to be of order 6.7.

    hep-phhep-exPRD(2018)·46 citations
18. 18*

    Probing axial quark generalized parton distributions through exclusive photoproduction of a $\gamma {\pi }^{\pm }$ pair with a large invariant mass

    G.Duplančić🇭🇷 · K.Passek-Kumerički🇭🇷 · B.Pire🇫🇷 · L.Szymanowski🇵🇱 · S.Wallon🇫🇷

    Exclusive photoproduction of a $\gamma {\pi }^{\pm }$ pair in the kinematics where the pair has a large invariant mass and the final nucleon has a small transverse momentum is described in the collinear factorization framework. The scattering amplitude is calculated at leading order in ${\alpha }_s$ and the differential cross sections for the process are estimated in the kinematics of the JLab~12-GeV experiments. The order of magnitude of the predicted cross-sections seems sufficient for a dedicated experiment to be performed. The process turns out to be very sensitive to the axial generalized parton distribution combination ${\tilde{H}}_u-{\tilde{H}}_d$.

    hep-phhep-exnucl-exnucl-thJHEP(2018)·58 citations
19. 19*

    Transport responses from rate of decay and scattering processes in the Nambu--Jona-Lasinio model

    Sabyasachi Ghosh🇮🇳 · Fernando E. Serna🇧🇷 · Aman Abhishek🇮🇳 · Gastao Krein🇧🇷 · Hiranmaya Mishra🇮🇳

    We have calculated quark and anti-quark relaxation time by considering different possible elastic and inelastic scatterings in the medium. Comparative role of these elastic and inelastic scatterings on different transport coefficients are explored. The quark-meson effective interaction Lagrangian density in the framework of Nambu--Jona-Lasinio model is used for calculating both type of scatterings. Owing to a kinetic threshold, inelastic scatterings can only exist beyond the Mott line in temperature and chemical potential plane, whereas elastic scatterings occur in the entire plane. Interestingly, the strength of inelastic scatterings near and above Mott line becomes so strong that medium behaves like a perfect fluid, in that all transport coefficients become very small.

    ↳ nucl-thhep-phPRD(2019)·22 citations
20. 20*

    Oscillons in Higher-Derivative Effective Field Theories

    Jeremy Sakstein🇺🇸 · Mark Trodden🇺🇸

    We investigate the existence and behavior of oscillons in theories in which higher derivative terms are present in the Lagrangian, such as galileons. Such theories have emerged in a broad range of settings, from higher-dimensional models, to massive gravity, to models for late-time cosmological acceleration. By focusing on the simplest example---massive galileon effective field theories---we demonstrate that higher derivative terms can lead to the existence of completely new oscillons (quasi-breathers). We illustrate our techniques in the artificially simple case of 1 + 1 dimensions, and then present the complete analysis valid in 2 + 1 and 3 + 1 dimensions, exploring precisely how these new solutions are supported entirely by the non-linearities of the quartic galileon. These objects have the novel peculiarity that they are of the differentiability class $C^1$.

    ↳ hep-thastro-ph.COgr-qchep-phPRD(2018)·13 citations
21. 21*

    Dark Matter from a Dark Connection

    Ranit Das🇺🇸 · Chethan Krishnan🇮🇳

    In the first part of this note, we observe that a non-Riemannian piece in the affine connection (a "dark connection") leads to an algebraically determined, conserved, symmetric 2-tensor in the Einstein field equations that is a natural dark matter candidate. The only other effect it has, is through its coupling to standard model fermions via covariant derivatives. If the local dark matter density is the result of a background classical dark connection, these Yukawa-like mass corrections are minuscule ($\sim 10^{-31}$ eV for terrestrial fermions) and {\em none} of the tests of general relativity or the equivalence principle are affected. In the second part of the note, we give dynamics to the dark connection and show how it can be re-interpreted in terms of conventional dark matter particles. The simplest way to do this is to treat it as a composite field involving scalars or vectors. The (pseudo-)scalar model naturally has a perturbative shift-symmetry and leads to versions of the Fuzzy Dark Matter (FDM) scenario that has recently become popular (eg., arXiv:1610.08297) as an alternative to WIMPs. A vector model with a ${\mathcal{Z}}_2$-parity falls into the Planckian Interacting Dark Matter (PIDM) paradigm, introduced in arXiv:1511.03278. It is possible to construct versions of these theories that yield the correct relic density, fit with inflation, and are falsifiable in the next round of CMB experiments. Our work is an explicit demonstration that the meaningful distinction is not between gravity modification and dark matter, but between theories with extra fields and those without.

    ↳ astro-ph.COgr-qchep-phhep-thMod.Phys.Lett.A(2021)·2 citations
22. 22*

    Generation of Circular Polarization of CMB via Polarized Compton Scattering

    Ali Vahedi🇮🇷 · Jafar Khodagholizadeh🇮🇷 · Rohoollah Mohammadi🇮🇷 · Mahdi Sadegh🇮🇷

    The standard scenario of cosmology predicts a measurable amount for linear polarization of the Cosmic Microwave Background radiation (CMB) via Thomson scattering, while through this scenario, the generation of circular polarization is excluded. On the another hand, the circular polarization of CMB has not been excluded in observational evidence. The generation of CMB photons circular polarization via their Compton scattering with polarized cosmic electrons is considered in this paper. Our motivation for considering polarized Compton scattering comes from the effects of the external magnetic field in large scale, the chiral magnetic instability and new physics interactions of the cosmic electrons. It is shown that damping term of polarized Compton scattering in the presence of scalar perturbation can generate circular polarization in CMB radiation, so that the power spectrum of circular polarization of CMB $C_l^{V(S)}$ is proportional to the power spectrum of temperature anisotropy of CMB $C_l^{I(S)}$ and also ${\delta }^2$ which is a fraction of polarized electron number density to the total one with net Left- or Right-handed polarizations. We have discussed that at least we need $\delta <10^{-4}$ to find consistency with a reported upper limit of CMB circular polarization.

    ↳ astro-ph.COastro-ph.HEhep-phJCAP(2019)·15 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.