Thu·Jan 31, 2019Thursday·January 31, 2019

1. 01*

   Flavor Changing Heavy Higgs Interactions with Leptons at Hadron Colliders

   Wei-Shu Hou🇹🇼 · Rishabh Jain🇺🇸 · Chung Kao🇺🇸 · Masaya Kohda🇹🇼 · Brent McCoy🇺🇸 · Amarjit Soni🇺🇸

   In a general two Higgs doublet model, we study flavor changing neutral Higgs (FCNH) decays into leptons at hadron colliders, $pp\to {\varphi }^0\to {\tau }^{\mp }{\mu }^{\pm }+X$, where ${\varphi }^0$ could be a CP-even scalar ($h^0$, $H^0$) or a CP-odd pseudoscalar ($A^0$). The light Higgs boson $h^0$ is found to resemble closely the Standard Model Higgs boson at the Large Hadron Collider. In the alignment limit of $\cos (\beta -\alpha )\cong 0$ for $h^0$--$H^0$ mixing, FCNH couplings of $h^0$ are naturally suppressed, but such couplings of the heavier $H^0,A^0$ are sustained by $\sin (\beta -\alpha )\simeq 1$. We evaluate physics backgrounds from dominant processes with realistic acceptance cuts and tagging efficiencies. We find promising results for $\sqrt{s}=14$ TeV, which we extend further to $\sqrt{s}=27$ TeV and 100 TeV future pp colliders.

   hep-phPLB(2019)·22 citations
2. 02*

   A Froggatt-Nielsen flavor model for neutrino physics

   Micheal S. Berger🇺🇸 · Maria Dawid🇺🇸

   Superheavy neutrinos can, via the seesaw model, provide a mechanism for lepton number violation. If they are combined with flavor violation as characterized by the Froggatt-Nielsen mechanism, then the phenomenology for the neutrinos in oscillation experiments, neutrinoless double beta decay, and other experiments can be described by a relatively few number of parameters. We describe the low-energy neutrino mass matrix and show that the results are consistent with currently available data.

   hep-phInt.J.Mod.Phys.A(2019)·3 citations
3. 03*

   Initial state description of azimuthally collimated long range correlations in ultrarelativistic light-heavy ion collisions

   Mark Mace🇫🇮 · Vladimir V. Skokov🇺🇸 · Prithwish Tribedy🇺🇸 · Raju Venugopalan🇺🇸

   It was argued in arXiv:1805.09342 and arXiv:1807.00825 that the systematics of the azimuthal anisotropy coefficients $v_{2,3}$ measured in ultrarelativistic light-heavy ion collisions at RHIC and the LHC can be described in an initial state dilute-dense Color Glass Condensate (CGC) framework. We elaborate here on the discussion in these papers and provide further novel results that strengthen their conclusions. The underlying mathematical framework and numerical techniques employed are very similar to those in the CGC based IP-Glasma model used previously as initial conditions for heavy-ion collisions. The uncertainties in theory/data comparisons for small systems are discussed, with unknowns that are specific to the model distinguished from those that are generic to all models. We present analytical arguments that demonstrate that quantum interference effects such as Bose enhancement and Hanbury-Brown-Twiss correlations of gluons, as well as coherent multiple scattering of gluons in the projectile off color domains in the target, are enhanced in rare events. The quantum origins of the large anisotropies in small systems are corroborated by numerical results for deuteron-gold collisions that show that large anisotropies in rare configurations can occur when the nucleons in the projectile overlap significantly. This is at variance with the classical intuition of hydrodynamical models. We also comment on the consequences of ignoring the many-body color charge correlations of gluons in models that only consider geometrical fluctuations in the energy density.

   hep-phnucl-exnucl-th6 citations
4. 04*

   Axialvector tetraquark candidates for the $Z_c(3900)$, $Z_c(4020)$, $Z_c(4430)$, $Z_c(4600)$

   Zhi-Gang Wang🇨🇳

   In this paper, we construct the axialvector and tensor current operators to investigate the ground state tetraquark states and the first radially excited tetraquark states with the quantum numbers $J^{PC}=1^{+-}$ via the QCD sum rules systematically, and observe that there are one axialvector tetraquark candidate for the $Z_c(3900)$ and $Z_c(4430)$, two axialvector tetraquark candidates for the $Z_c(4020)$, three axialvector tetraquark candidates for the $Z_c(4600)$.

   hep-phCPC(2020)·36 citations
5. 05*

   Analytical solutions to renormalization-group equations of effective neutrino masses and mixing parameters in matter

   Xin Wang🇨🇳 · Shun Zhou🇨🇳

   Recently, a complete set of differential equations for the effective neutrino masses and mixing parameters in matter have been derived to characterize their evolution with respect to the ordinary matter term $a\equiv 2\sqrt{2}{G}_{\mathrm{F}}^{}{N}_e^{}E$, in analogy with the renormalization-group equations (RGEs) for running parameters. Via series expansion in terms of the small ratio ${\alpha }_{\mathrm{c}}^{}\equiv {\Delta }_{21}^{}/{\Delta }_{\mathrm{c}}^{}$, we obtain approximate analytical solutions to the RGEs of the effective neutrino parameters and make several interesting observations. First, at the leading order, ${\tilde{\theta }}_{12}^{}$ and ${\tilde{\theta }}_{13}^{}$ are given by the simple formulas in the two-flavor mixing limit, while ${\tilde{\theta }}_{23}^{}\approx {\theta }_{23}^{}$ and $\tilde{\delta }\approx \delta$ are not changed by matter effects. Second, the ratio of the matter-corrected Jarlskog invariant $\tilde{\mathcal{J}}$ to its counterpart in vacuum $\mathcal{J}$ approximates to $\tilde{\mathcal{J}}/\mathcal{J}\approx 1/({\hat{C}}_{12}^{}{\hat{C}}_{13}^{})$, where ${\hat{C}}_{12}^{}\equiv \sqrt{1-2A_{\ast }^{}\cos 2{\theta }_{12}^{}+A_{\ast }^2}$ with $A_{\ast }^{}\equiv a/{\Delta }_{21}^{}$ and ${\hat{C}}_{13}^{}\equiv \sqrt{1-2A_{\mathrm{c}}^{}\cos 2{\theta }_{13}^{}+A_{\mathrm{c}}^2}$ with $A_{\mathrm{c}}^{}\equiv a/{\Delta }_{\mathrm{c}}^{}$. Finally, after taking higher-order corrections into account, we find compact and simple expressions of all the effective parameters.

   hep-phJHEP(2019)·21 citations
6. 06*

   Slightly Ultra-violet Freeze-in a Hidden Gluonic Sector

   Zhaofeng Kang🇨🇳

   The dark glueball (DGB) from a hidden Yang-Mills sector is a simple non-WIMP dark matter candidate characterized by very few parameters. However, it suffers the over dense issue. To overcome it, in general the dark sector is required to be hierarchically cooler than the visible sector. To naturally generate the desired hierarchy, in this paper we introduce higher dimensional operators coupling the dark gauge field strength tensor to the standard model (SM) Higgs doublets or gauge field strength tensors. By tracking the different phases of the universe from the end of inflation, prethermalization, reheating to the radiation dominance era, we show that these operators can make the DGB be a viable dark matter candidate over a wide mass region, from the sub-GeV to multi-PeV or even beyond. At the same time, these operators open decay channels of DGB to the SM species, and partial of the parameter space could leave hints in the cosmic ray.

   hep-phastro-ph.COPLB(2020)·9 citations
7. 07*

   Two-loop $N$-jettiness soft function for $pp\to 2j$ production

   Shan Jin🇰🇷 · Xiaohui Liu🇨🇳

   We calculate the two-loop soft function for $pp\to jj$, $e^{+}{e}^{-}\to 4j$ or $ep\to 3j$ when the $N$-jettiness observable is measured. The result presented here makes up the necessary piece for realizing the full next-to-next-to-leading order predictions for these processes using the $N$-jettiness subtraction scheme.

   hep-phPRD(2019)·11 citations
8. 08*

   Phenomenology of a universal super weak $SU(N{)}_w$ color hypothesis

   Lobsang Dhargyal🇮🇳

   In this work we will propose a new universal super weak $SU(N{)}_w$ (or self interacting vector bosons) color to which all the SM fermions are assumed to be coupled universally whose confining radius is in the range of the size of galaxies. We will argue that the model has some very interesting consequences such as it could be able to explain the observed rotation velocity anomalies in large galaxies without requirement of specific DM particle. We will also show that it could constitute most of the observed mass of a galaxy, similar like the proton mass which is mostly made up of color interaction dynamics as shown recently, which could explain the observed DM in the rotation velocities of galaxies in galaxy clusters. Also when the N is very small, we will show that it could explain the Big Bang and Hubble's law, Dark Energy, and tentatively also flavor and neutrino oscillation.

   hep-ph0 citations
9. 09*

   Future heavy-ion facilities: FCC-AA

   A. Dainese🇮🇹 · L. Apolinario🇵🇹 · N. Armesto🇪🇸 · D. d'Enterria🇨🇭 · J.M. Jowett🇨🇭 · J.-P. Lansberg🇫🇷 · J.G. Milhano🇵🇹 · C.A. Salgado🇪🇸 · M. Schaumann🇨🇭 · M. van Leuween🇳🇱 · U.A. Wiedemann🇨🇭

   The operation of the Future Circular Collider (FCC) with heavy ions would provide Pb-Pb and p-Pb collisions at sqrt{s_NN}= 39 and 63 TeV, respectively, per nucleon-nucleon collision, with projected per-month integrated luminosities of up to 110/nb and 29/pb, respectively. This document outlines the unique and broad physics opportunities with heavy ions at the energy frontier opened by FCC.

   hep-phnucl-exnucl-thPoS(2019)·3 citations
10. 10*

    Modeling neutrino-nucleus interactions for neutrino oscillation experiments

    G. D. Megias🇪🇸 · S. Dolan🇫🇷 · S. Bolognesi🇫🇷

    We present our recent progress on the relativistic modeling of neutrino-nucleus reactions for their implementation in MonteCarlo event generators (GENIE, NEUT) employed in neutrino oscillation experiments. We compare charged-current neutrino and antineutrino cross sections obtained within the SuSAv2 model, which is based on the Relativistic Mean Field theory and on the analysis of the superscaling behavior exhibited by ($e,e^{\prime }$) data. We also evaluate and discuss the impact of multi-nucleon excitations arising from 2p-2h states excited by the action of weak forces in a fully relativistic framework, showing for the first time their implementation in GENIE and their comparison with recent T2K data.

    hep-phhep-exnucl-thSpringer Proc.Phys.(2019)·4 citations
11. 11*

    Dark Matter Production during the Thermalization Era

    Keisuke Harigaya🇺🇸 · Kyohei Mukaida🇩🇪 · Masaki Yamada🇺🇸

    We revisit the non-thermal dark matter (DM) production during the thermalization and reheating era after inflation. The decay of inflaton produces high-energy particles that are thermalized to complete the reheating of the Universe. Before the thermalization is completed, DM can be produced from a collision between the high-energy particles and/or the ambient plasma. We calculate the DM abundance produced from these processes for the case where the cross section of the DM production is proportional to the $n$-th power of the center of mass energy. We find that the collision between the high-energy particles is almost always dominant for $n\gtrsim 4$ while it is subdominant for $n\lesssim 2$. The production from the ambient plasma is dominant when $n\lesssim 3$ and the reheating temperature is of the order of or larger than the DM mass. The production from a collision between the high-energy particle and the ambient plasma is important for $n\lesssim 2$ and the reheating temperature is much lower than the DM mass.

    hep-phastro-ph.COJHEP(2019)·78 citations
12. 12*

    HYTREES: Combining Matrix Elements and Parton Shower for Hypothesis Testing

    Stefan Prestel🇸🇪 · Michael Spannowsky🇬🇧

    We present a new way of performing hypothesis tests on scattering data, by means of a perturbatively calculable classifier. This classifier exploits the "history tree" of how the measured data point might have evolved out of any simpler (reconstructed) points along classical paths, while explicitly keeping quantum-mechanical interference effects by copiously employing complete leading-order matrix elements. This approach extends the standard Matrix Element Method to an arbitrary number of final state objects and to exclusive final states where reconstructed objects can be collinear or soft. We have implemented this method into the standalone package HYTREES and have applied it to Higgs boson production in association with two jets, with subsequent decay into photons. HYTREES allows to construct an optimal classifier to discriminate this process from large Standard Model backgrounds. It further allows to find the most sensitive kinematic regions that contribute to the classification.

    hep-phEPJC(2019)·21 citations
13. 13*

    Hearing without seeing: gravitational waves from hot and cold hidden sectors

    Malcolm Fairbairn🇬🇧 · Edward Hardy🇬🇧 · Alastair Wickens🇬🇧

    We study the spectrum of gravitational waves produced by a first order phase transition in a hidden sector that is colder than the visible sector. In this scenario, bubbles of the hidden sector vacuum can be nucleated through either thermal fluctuations or quantum tunnelling. If a cold hidden sector undergoes a thermally induced transition, the amplitude of the gravitational wave signal produced will be suppressed and its peak frequency shifted compared to if the hidden and visible sector temperatures were equal. This could lead to signals in a frequency range that would otherwise be ruled out by constraints from big bang nucleosynthesis. Alternatively, a sufficiently cold hidden sector could fail to undergo a thermal transition and subsequently transition through the nucleation of bubbles by quantum tunnelling. In this case the bubble walls might accelerate with completely negligible friction. The resulting gravitational wave spectrum has a characteristic frequency dependence, which may allow such cold hidden sectors to be distinguished from models in which the hidden and visible sector temperatures are similar. We compare our results to the sensitivity of the future gravitational wave experimental programme.

    hep-phastro-ph.COJHEP(2019)·116 citations
14. 14*

    Vector Boson Production in Association with a Jet at Forward Rapidities

    A. Gehrmann-De Ridder🇨🇭 · T. Gehrmann🇨🇭 · E. W. N. Glover🇬🇧 · A. Huss🇨🇭 · D. M. Walker🇬🇧

    Final states with a vector boson and a hadronic jet allow one to infer the Born-level kinematics of the underlying hard scattering process, thereby probing the partonic structure of the colliding protons. At forward rapidities, the parton collisions are highly asymmetric and resolve the parton distributions at very large or very small momentum fractions, where they are less well constrained by other processes. Using theory predictions accurate to next-to-next-to-leading order (NNLO) in QCD for both ${\mathrm{W}}^{\pm }$ and $\mathrm{Z}$ production in association with a jet at large rapidities at the LHC, we perform a detailed phenomenological analysis of recent LHC measurements. The increased theory precision allows us to clearly identify specific kinematical regions where the description of the data is insufficient. By constructing ratios and asymmetries of these cross sections, we aim to identify possible origins of the deviations, and highlight the potential impact of the data on improved determinations of parton distributions.

    hep-phEPJC(2019)·27 citations
15. 15*

    Exact Greybody Factors for the Brane Scalar Field of Five-dimensional Rotating Black Holes

    Young-Hwan Hyun🇰🇷 · Yoonbai Kim🇰🇷 · Seong Chan Park🇰🇷

    We study scalar perturbations of the five-dimensional rotating black holes and find an exact solution giving exact description of the Hawking radiation. Mathematically, the full solution for this s-wave mode is expressed in terms of the prolate spheroidal wave function with complex parameters. By using the spheroidal joining factor, we write the corresponding boundary condition and greybody factors. We also check that the exact result reproduces the low frequency limit of the greybody factor and shows good agreement with the known numerical results.

    ↳ gr-qchep-phhep-thJHEP(2019)·8 citations
16. 16*

    Search for axionlike dark matter with a liquid-state nuclear spin comagnetometer

    Teng Wu🇩🇪 · John W. Blanchard🇩🇪 · Gary P. Centers🇩🇪 · Nataniel L. Figueroa🇩🇪 · Antoine Garcon🇩🇪 · Peter W. Graham🇺🇸 · Derek F. Jackson Kimball🇺🇸 · Surjeet Rajendran🇺🇸 · Yevgeny V. Stadnik🇩🇪 · Alexander O. Sushkov🇺🇸 · Arne Wickenbrock🇩🇪 · Dmitry Budker🇩🇪

    We report the results of a search for axionlike dark matter using nuclear magnetic resonance (NMR) techniques. This search is part of the multi-faceted Cosmic Axion Spin Precession Experiment (CASPEr) program. In order to distinguish axionlike dark matter from magnetic fields, we employ a comagnetometry scheme measuring ultralow-field NMR signals involving two different nuclei (${}^{13}$C and ${}^1$H) in a liquid-state sample of acetonitrile-2-${}^{13}$C (${}^{13}$CH${}_3$CN). No axionlike dark matter signal was detected above background. This result constrains the parameter space describing the coupling of the gradient of the axionlike dark matter field to nucleons to be $g_{aNN}<6\times 10^{-5}$ GeV${}^{-1}$ (95$\%$ confidence level) for particle masses ranging from $10^{-22}$ eV to $1.3\times 10^{-17}$ eV, improving over previous laboratory limits for masses below $10^{-21}$ eV. The result also constrains the coupling of nuclear spins to the gradient of the square of the axionlike dark matter field, improving over astrophysical limits by orders of magnitude over the entire range of particle masses probed.

    ↳ hep-exhep-phPRL(2019)·151 citations
17. 17*

    Evolution of multiplicity fluctuations in heavy ion collisions

    Radka Sochorova🇨🇿 · Boris Tomasik🇸🇰

    The evolution of multiplicity distribution of a species which undergoes chemical reactions can be described with the help of a master equation. We study the master equation for a fixed temperature, because we want to know how fast different moments of the multiplicity distribution approach their equilibrium value. We particularly look at the 3rd and 4th factorial moments and their equilibrium values from which central moments, cumulants and their ratios can be calculated. Then we study the situation in which the temperature of the system decreases. We find out that in the non-equilibrium state, higher factorial moments differ more from their equilibrium values than the lower moments and that the behaviour of the combination of the central moments depends on the combination we choose. If one chooses to determine the chemical freeze-out temperature from the measured values of higher moments, these effects might jeopardise the correctness of the extracted value.

    ↳ nucl-thhep-phnucl-exPoS(2019)·0 citations
18. 18*

    Detecting Axion-like Dark Matter with Linearly Polarized Pulsar Light

    Tao Liu🇨🇳 · George Smoot🇨🇳 · Yue Zhao🇺🇸

    Non-relativistic QCD axions or axion-like particles are among the most popular candidates for cold Dark Matter (DM) in the universe. We proposed to detect axion-like DM, using linearly polarized pulsar light as a probe. Because of birefringence effect potentially caused by an oscillating galactic axion DM background, when pulsar light travels across the galaxy, its linear polarization angle may vary with time. With a soliton+NFW galactic DM density profile, we show that this strategy can potentially probe an axion-photon coupling as small as $\sim 10^{-13}$ GeV${}^{-1}$ for axion mass $m_a\sim 10^{-22}-10^{-20}$ eV, given the current measurement accuracy. An exclusion limit stronger than CAST ($\sim 10^{-10}$ GeV${}^{-1}$) and SN1987A ($\sim 10^{-11}$ GeV${}^{-1}$) could be extended up to $m_a\sim 10^{-18}$ eV and $\sim 10^{-19}$ eV, respectively.

    ↳ astro-ph.COastro-ph.GAhep-phhep-thPRD(2020)·69 citations
19. 19*

    The Eötvös Paradox: The Enduring Significance of Eötvös' Most Famous Paper

    Ephraim Fischbach🇺🇸 · Dennis E. Krause🇺🇸

    Following the death of Baron Loránd von Eötvös in 1919, his collaborators Desiderius Pekár and Eugen Fekete co-authored a paper in 1922 containing the results of a series of earlier experiments testing the identity of inertial and gravitational mass, the Weak Equivalence Principle (WEP). Although the so-called "EPF" paper made no claim for any WEP violations, a subsequent 1986 reanalysis of the EPF paper revealed a pattern in their data suggesting the presence of a new ("fifth") force in nature. Although the EPF data, and the 1986 reanalysis of these data, present fairly compelling evidence for such a fifth force, many contemporary experiments have failed to detect its presence. Here we summarize the key elements of this "Eötvös paradox," and suggest some possible paths to a resolution. Along the way we also discuss the close relationship between Eötvös and Einstein, and consider how their respective contributions may have been influenced by the other's.

    ↳ physics.hist-phgr-qchep-phPoS(2020)·7 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.