HEP Phenomenology·hep-ph

Tue·Aug 20, 2019Tuesday·August 20, 2019

34 papers—27 primary·7 cross-listed·reconstructed*

01*
Nucleon's energy-momentum tensor form factors in light-cone QCD
K. Azizi🇮🇷 · U. Ozdem🇹🇷
We use the energy-momentum tensor (EMT) current to compute the EMT form factors of the nucleon in the framework of the light cone QCD sum rule formalism. In the calculations, we employ the most general form of the nucleon's interpolating field and use the distribution amplitudes (DAs) of the nucleon with two sets of the numerical values of the main input parameters entering the expressions of the DAs. The directly obtained results from the sum rules for the form factors are reliable at $Q^{2} \geq 1 G e V^{2}$ : To extrapolate the results to include the zero momentum transfer squared with the aim of estimation of the related static physical quantities, we use some fit functions for the form factors. The numerical computations show that the energy-momentum tensor form factors of the nucleon can be well fitted to the multipole fit form. We compare the results obtained for the form factors at $Q^{2} = 0$ with the existing theoretical predictions as well as experimental data on the gravitational form factor d $_{1}^{q} (0)$ . For the form factors M $_{2}^{q} (0)$ and J $^{q} (0)$ a consistency among the theoretical predictions is seen within the errors: Our results are nicely consistent with the Lattice QCD and chiral perturbation theory predictions. However, there are large discrepancies among the theoretical predictions on d $_{1}^{q} (0)$ . Nevertheless, our prediction is in accord with the JLab data as well as with the results of the Lattice QCD, chiral perturbation theory and KM15-fit. Our fit functions well define most of the JLab data in the interval $Q^{2} \in [0, 0.4] G e V^{2}$ , while the Lattice results suffer from large uncertainties in this region. As a by-product, some mechanical properties of the nucleon like the pressure and energy density at the center of nucleon as well as its mechanical radius are also calculated and their results are compared with other existing theoretical predictions.
hep-phhep-exhep-latEPJC(2020)·60 citations
02*
The Heavy Gluino in Natural No-Scale $F$ - $S U$ (5)
Thomas Ford🇺🇸 · Tianjun Li🇨🇳 · James A. Maxin🇺🇸 · Dimitri V. Nanopoulos🇺🇸
In light of recent 80-137 $fb^{- 1}$ results at the LHC Run 2 establishing a lower gluino mass limit of 2.25 TeV, we revisit the supersymmetric GUT model Flipped $S U$ (5) with extra vector-like particles, known as $F$ - $S U$ (5), with vanishing No-Scale Supergravity boundary conditions at the string scale of about $2 \times 1 0^{17}$ GeV, including the supersymmetry breaking $B_{μ}$ parameter which is strictly enforced as $B_{μ} = 0$ . Given the proportional dependence of all model scales on a single parameter $M_{1/2}$ , No-Scale $F$ - $S U$ (5) was shown to possess no electroweak fine-tuning and thus persists as a $na t u r a l$ one-parameter model. In this fresh analysis here, we demand consistency with the measured 125 GeV light Higgs boson mass, though we forgo an upper limit on the lightest neutralino relic density. The resulting phenomenology delivers a gluino mass of $M (g) ≲ 7.5$ TeV and a lightest supersymmetric particle (LSP) of $M (χ_{1}^{0}) ≲ 1.6$ TeV. In order to dilute the relic density down to the WMAP and Planck measurements, we rely upon a single cosmological master coupling $λ_{6}$ .
hep-phhep-exPLB(2019)·3 citations
03*
Quantum Critical Higgs: From AdS $_{5}$ to Colliders
Ali Shayegan Shirazi🇺🇸 · John Terning🇺🇸
We examine distinctive signatures of Quantum Critical Higgs models at the LHC and future higher energy colliders. In these models the Higgs boson is part of a conformal sector that is softly broken at a threshold scale, and generically the scaling dimension of the Higgs is larger than in the Standard Model. In particular we examine the $g g \to H \to Z Z$ , $g g \to H \to γ γ$ , and $g g \to Z \to H Z$ channels to see how the cross sections deviate from the Standard Model in the high invariant mass region. In order to perform the calculations we use 5D duals of Quantum Critical Higgs models using the AdS/CFT correspondence, with a soft wall to break the conformal symmetry.
hep-phJHEP(2020)·3 citations
04*
Effects of universal extra dimensions on top-quark electromagnetic interactions
Javier Montaño🇲🇽 · Héctor Novales-Sánchez🇲🇽 · J. Jesús Toscano🇲🇽
Universal extra dimensions, presumably observable at some high-energy scale, would modify low-energy observables, being particularly relevant for physical processes forbidden at tree level by the Standard Model. We address the Kaluza-Klein contributions from the 5-dimensional Standard Model to the anomalous magnetic moment and to branching ratios of electromagnetic decays of the top quark. In accordance with present bounds on the compactification scale, contributions to both quantities are found to be at least 3 orders of magnitude below Standard-Model predictions.
hep-phJ.Phys.G(2019)·8 citations
05*
Signature of lepton flavor universality violation in $B_{s} \to D_{s} τ ν$ semileptonic decays
Rupak Dutta🇮🇳 · N Rajeev🇮🇳
Deviation from the standard model prediction is observed in many semileptonic $B$ decays mediated via $b \to c$ charged current interactions. In particular, current experimental measurements of the ratio of branching ratio $R_{D}$ and $R_{D^{*}}$ in $B \to D^{(*)} l ν$ decays disagree with standard model expectations at the level of about $4.1 σ$ . Moreover, recent measurement of the ratio of branching ratio $R_{J /Ψ}$ by LHCb, where $R_{J /Ψ} = B (B_{c} \to J /Ψ τ ν) / B (B_{c} \to J /Ψ μν)$ , is more than $2 σ$ away from the standard model prediction. In this context, we consider an effective Lagrangian in the presence of vector and scalar new physics couplings to study the implications of $R_{D}$ and $R_{D^{*}}$ anomalies in $B_{s} \to D_{s} τ ν$ decays. We give prediction of several observables such as branching ratio, ratio of branching ratio, forward backward asymmetry parameter, $τ$ polarization fraction, and the convexity parameter for the $B_{s} \to D_{s} τ ν$ decays within the standard model and within various new physics scenarios.
hep-phSpringer Proc.Phys.(2019)·2 citations
06*
Probing new physics in $B_{s} \to (K, K^{*}) τ ν$ and $B \to π τ ν$ decays
N Rajeev🇮🇳 · Rupak Dutta🇮🇳
Motivated by the anomalies present in $b \to u$ and $b \to c$ semileptonic decays, we study the corresponding $B_{s} \to (K, K^{*}) τ ν$ and $B \to π τ ν$ decays within an effective field theory formalism. Our analysis is based on a strict model dependent assumption, i.e., we assume that $b \to u$ and $b \to c$ transition decays exhibit similar new physics pattern. We give prediction of various observables such as the branching fraction, ratio of branching ratio, lepton side forward-backward asymmetry, longitudinal polarization fraction of the charged lepton and convexity parameter in the standard model and in the presence of vector type new physics couplings.
hep-phSpringer Proc.Phys.(2021)·0 citations
07*
Is the Momentum Sum Rule Valid for Nuclear Structure Functions ?
Stanley J. Brodsky🇺🇸 · Ivan Schmidt🇨🇱 · Simonetta Liuti🇺🇸
We address the validity of the momentum sum rule for deep inelastic nuclear structure functions.
hep-phnucl-th13 citations
08*
Precision measurement of the Z boson to electron neutrino coupling at the future circular colliders
R. Aleksan🇫🇷 · S. Jadach🇵🇱
At the high luminosity electron-positron circular colliders like FCC-ee in CERN and CEPC in China it will possible to measure very precisely $e^{+} e^{-} \to Z γ$ process with subsequent Z decay into particles invisible in the detector, that is into three neutrina of the Standard Model and possibly into other weakly coupled neutral particles. Apart from the measurement of the total invisible width (which is not the main subject of this work) this process may be used as a source of $Z$ coupling to electron neutrino -- known very poorly. This is possible due to the presence of the $t$ -channel $W$ exchange in the $e^{+} e^{-} \to ν_{e} ν ˉ_{e} γ$ channel which deforms slightly spectrum of the photon. We are going to show experimental investigation of this effect, for $\sim 10$ inverse atobarn accumulated luminosity, which can provide measurement of the $Z - ν_{e}$ coupling with statistical error of order 1\%. The estimation of the systematic experimental error will require more work, but most likely it will be of similar size.
hep-phhep-exPLB(2019)·8 citations
09*
Search for Vector-mediated Dark Matter at the LHC with Forward Proton Tagging
Gi-Chol Cho🇯🇵 · Kimiko Yamashita🇹🇼 · Miki Yonemura🇯🇵
We investigate the production of fermionic dark matter $χ$ via $pp \to p γ p \to p j χ χ ˉ X$ mediated by a leptophobic spin-1 particle, where one of the protons remains intact and is tagged by forward proton detectors. We find that the masses of $χ$ and the mediator $Z^{'}$ are severely constrained when $Z^{'}$ interacts with $χ$ and quarks through the vector couplings. We show that dark matter searches in this production channel are sensitive to a mediator mass $m_{Z^{'}} ≲ 1.4 TeV$ at 14 TeV at the LHC with an integrated luminosity $L_{int} = 3000 fb^{- 1}$ . The lower mass bound on the dark matter is $m_{χ} ≃ 550 GeV$ at the mediator mass $m_{Z^{'}} = 1.2 TeV$ .
hep-phhep-exPRD(2020)·2 citations
10*
Impact of LHC top-quark pair measurements to CTEQ-TEA PDF analysis
Orkash Amat🇨🇳 · Michał Czakon🇩🇪 · Sayipjamal Dulat🇨🇳 · Tie-Jiun Hou🇨🇳 · Joey Huston🇺🇸 · Alexander Mitov🇬🇧 · Andrew S.~Papanastasiou · Carl Schmidt🇺🇸 · Ibrahim Sitiwaldi🇨🇳 · Keping Xie🇺🇸 · Zhite Yu🇺🇸 · C.-P. Yuan🇺🇸
Detailed studies have been carried out on the impact of the LHC top quark pair production data on gluon PDF, in the context of the CTEQ-TEA global PDF fit, with the ePump-updating method. The considered $t t ˉ$ data include single differential distributions from ATLAS and double differential distributions from CMS, both at 8 TeV. All analyses have been carried out at the NNLO, using fastNNLO tables. We show that the sensitivity per data point of the LHC $t t ˉ$ data is similar to that of jet data, as included in the CT14HERA2 fit, while the total sensitivity of the present $t t ˉ$ data is not as large as the jet data because of the much smaller number of $t t ˉ$ data points in the presently available data.
hep-phPoS(2019)·8 citations
11*
Non-strange quark stars from NJL model with proper-time regularisation
Qingwu Wang🇨🇳 · Chao Shi🇨🇳 · Hong-Shi Zong🇨🇳
The structure of light quark star is studied within a new two-flavor NJL model. By retaining the contribution from the vector term in the Fierz-transformed Lagrangian, a two-solar-mass pure quark star is achieved. To overcome the disadvantage of three-momentum truncation in the regularisation procedure, we introduce the proper-time regularisation. We also employ the newly proposed definition of vacuum pressure, in which the quasi-Wigner vacuum (corresponding to the quasi-Winger solution of the gap equation) is used as the reference ground state. Free parameter includes only a mixing constant $α$ which weighs contribution from Fierz-transformed Lagrangian. We constrain $α$ to be around $0.9$ by the observed mass of pulsars $P S R J 0348 + 0432$ and $P S R J 1614 - 2230$ . We find the calculated surface energy density meets the requirement ( $> 2.80 \times 1 0^{14}$ g/cm $^{3}$ ). Besides, for a 1.4 solar mass star, the tidal Love number $k_{2}$ and deformability $Λ$ are calculated which satisfies the constrain $200 < Λ < 800$ .
hep-phastro-ph.HEPRD(2019)·51 citations
12*
Higher-order perturbative coefficients in QCD from series acceleration by conformal mappings
Irinel Caprini🇷🇴
The present calculations in perturbative QCD reach the order $α_{s}^{4}$ for several correlators calculated to five loops, and the huge computational difficulties make unlikely the full six-loop calculation in the near future. This situation has practical consequences, in particular the treatment of the higher orders of the perturbation series for the current-current correlator of light quarks is one of the main sources of errors in the extraction of the strong coupling from hadronic $τ$ decays. Several approximate estimates of the next coefficients of the corresponding Adler function have been proposed, using various arguments. In the present paper we exploit the analytic structure of the Adler function in the Borel plane, which allows the definition of an improved perturbative expansion in powers of a conformal variable which maps the cut Borel plane onto the unit disk. The new expansions converge in a larger domain of the Borel plane and, when reexpanded in powers of the strong coupling, yield definite values for the higher perturbative coefficients. We apply the method to the Adler function in the $MS ˉ$ scheme and to a suitable weighted integral of this function in the complex $s$ plane, chosen such as to avoid model-dependent assumptions on analyticity. Our results $c_{5, 1} = 287 \pm 40$ , $c_{6, 1} = 2948 \pm 208$ and $c_{7, 1} = (1.89 \pm 0.75) \times 1 0^{4}$ , for the six, seven and eigth-loop coefficients, respectively, agree with a recent determination from Padé approximants applied to the perturbative expansion of the hadronic $τ$ decay rate.
hep-phPRD(2019)·28 citations
13*
Chiral condensates in massless QCD and the $U (1)_{A}$ boson mass
Thomas Mannel🇩🇪 · Alexei A. Pivovarov🇩🇪
The $U (1)_{A}$ boson mass is calculated through the phenomenological characteristics of the vacuum related to spontaneous breaking of chiral symmetry in QCD. The mass is determined by the mixed quark-gluon condensate $⟨ q ˉ Gq ⟩$ that emerges in an appropriate correlation function due to triangle anomaly. For three flavor QCD in chiral limit we find the numerical value for the $U (1)_{A}$ boson mass to be $M_{0} = 310 \pm 50 MeV$ .
hep-ph1 citation
14*
Exploring the scattering of vector bosons at LHCb
Mathieu Pellen🇬🇧
In this letter, I propose a strategy to measure vector-boson scattering (VBS) at the LHCb experiment. The typical VBS topology at hadron colliders features two energetic back-to-back jets with large rapidities and two gauge bosons produced centrally. In this article, I show that such a topology can actually be probed by the LHCb detector. In particular, tagging only one of the two jets in combination with two same-sign leptons allows for a measurement with upcoming luminosities. I present an illustrative event selection where cross sections and differential distributions are computed for VBS and its irreducible background.
hep-phhep-exPRD(2020)·7 citations
15*
Cross section ratios as a precision tool for $t t ˉ γ$
Manfred Kraus🇩🇪
We report on our recent calculation for the off-shell ttA process and its potential for precision measurements by constructing ratios of total and differential cross sections. Precise theoretical predictions for these ratios can help to constrain new physics contributions in the top-quark sector of the Standard Model.
hep-ph0 citations
16*
Jet charge modification in dense QCD matter
Hai Tao Li🇺🇸 · Ivan Vitev🇺🇸
Jet production and jet substructure modification in heavy-ion collisions have played an essential role in revealing the in-medium evolution of parton showers and the determination of the properties of strongly-interacting matter under extreme conditions. It is imperative to extend these studies to include flavor tagging and to devise observables that are sensitive to the partonic origin of jets. The average jet charge, defined as the momentum-weighted sum of the electric charges of particles inside the jet, is a proxy of the electric charge of the quark or gluon that initiates the jet. We demonstrate how the factorization framework of soft-collinear effective theory can be generalized to evaluate the jet charge in a dense strongly-interacting matter environment, such as the one produced in nuclear reactions at collider energies. Observables that can separate the contribution of in-medium branching from the trivial isospin effects are identified and their connection to established jet quenching effects is elucidated. We present predictions for the transverse momentum dependence of the jet charge distribution in nucleus-nucleus collisions and its modification relative to the proton case.
hep-phhep-exnucl-thPRD(2020)·51 citations
17*
Benchmarking simplified template cross sections in $W H$ production
Johann Brehmer🇺🇸 · Sally Dawson🇺🇸 · Samuel Homiller🇺🇸 · Felix Kling🇺🇸 · Tilman Plehn🇩🇪
Simplified template cross sections define a framework for the measurement and dissemination of kinematic information in Higgs measurements. We benchmark the currently proposed setup in an analysis of dimension-6 effective field theory operators for $W H$ production. Calculating the Fisher information allows us to quantify the sensitivity of this framework to new physics and study its dependence on phase space. New machine-learning techniques let us compare the simplified template cross section framework to the full, high-dimensional kinematic information. We show that the way in which we truncate the effective theory has a sizable impact on the definition of the optimal simplified template cross sections.
hep-phJHEP(2019)·62 citations
18*
Direct Deflection of Particle Dark Matter
Asher Berlin🇺🇸 · Raffaele Tito D'Agnolo🇺🇸 · Sebastian A. R. Ellis🇺🇸 · Philip Schuster🇺🇸 · Natalia Toro🇺🇸
We propose a new strategy to directly detect light particle dark matter that has long-ranged interactions with ordinary matter. The approach involves distorting the local flow of dark matter with time-varying fields and measuring these distortions with shielded resonant detectors. We apply this idea to sub-MeV dark matter particles with very small electric charges or coupled to a light vector mediator, including the freeze-in parameter space targeted by low mass direct detection efforts. This approach can probe dark matter masses ranging from 10 MeV to below a meV, extending beyond the capabilities of existing and proposed direct detection experiments.
hep-phhep-exPRL(2020)·46 citations
19*
A uniform locally constant field approximation for photon-seeded pair production
B. King🇬🇧
A challenge to upcoming experiments that plan to collide a particle beam with laser pulses of moderate intensity is how to correctly incorporate quantum effects into simulation frameworks. Using a uniform approach, we extend the widely-used locally constant field approximation (LCFA) to derive an improved rate of photon-seeded pair creation (the nonlinear Breit-Wheeler process). By benchmarking our "ULCFA" expressions with the lightfront spectrum of: i) exact analytical results and ii) numerical integration of the QED probability for short pulses, we show that our extended approach remains accurate at smaller values of the intensity parameter than the standard LCFA.
hep-phphysics.plasm-phquant-phPRA(2020)·45 citations
20*
Reviving Millicharged Dark Matter for 21-cm Cosmology
Hongwan Liu🇺🇸 · Nadav Joseph Outmezguine🇮🇱 · Diego Redigolo🇮🇱 · Tomer Volansky🇮🇱
The existence of millicharged dark matter (mDM) can leave a measurable imprint on 21-cm cosmology through mDM-baryon scattering. However, the minimal scenario is severely constrained by existing cosmological bounds on both the fraction of dark matter that can be millicharged and the mass of mDM particles. We point out that introducing a long-range force between a millicharged subcomponent of dark matter and the dominant cold dark matter (CDM) component leads to efficient cooling of baryons in the early universe, while also significantly extending the range of viable mDM masses. Such a scenario can explain the anomalous absorption signal in the sky-averaged 21-cm spectrum observed by EDGES, and leads to a number of testable predictions for the properties of the dark sector. The mDM mass can then lie between 10 MeV and a few hundreds of GeVs, and its scattering cross section with baryons lies within an unconstrained window of parameter space above direct detection limits and below current bounds from colliders. In this allowed region, mDM can make up as little as $1 0^{- 8}$ of the total dark matter energy density. The CDM mass ranges from 10 MeV to a few GeVs, and has an interaction cross section with the Standard Model that is induced by a loop of mDM particles. This cross section is generically within reach of near-future low-threshold direct detection experiments.
hep-phastro-ph.COPRD(2019)·161 citations
21*
MiNNLO $_{PS}$ : A new method to match NNLO QCD to parton showers
Pier Francesco Monni🇨🇭 · Paolo Nason🇮🇹 · Emanuele Re🇨🇭 · Marius Wiesemann🇩🇪 · Giulia Zanderighi🇩🇪
We present a novel method to combine QCD calculations at next-to-next-to-leading order (NNLO) with parton shower (PS) simulations, that can be applied to the production of heavy systems in hadronic collisions, such as colour singlets or a $t t ˉ$ pair. The NNLO corrections are included by connecting the MiNLO $^{'}$ method with transverse-momentum resummation, and they are calculated at generation time without any additional reweighting, making the algorithm considerably efficient. Moreover, the combination of different jet multiplicities does not require any unphysical merging scale, and the matching preserves the structure of the leading logarithmic corrections of the Monte Carlo simulation for parton showers ordered in transverse momentum. We present proof-of-concept applications to hadronic Higgs production and the Drell-Yan process at the LHC.
hep-phhep-exJHEP(2020)·230 citations
22*
Neutrino mass ordering obscured by non-standard interactions
Francesco Capozzi🇩🇪 · Sabya Sachi Chatterjee🇬🇧 · Antonio Palazzo🇮🇹
One of the major open questions in particle physics is the issue of the neutrino mass ordering (NMO). The current data of the two long-baseline experiments NO $ν$ A and T2K, interpreted in the standard 3-flavor scenario, provide a $\sim 2.4 σ$ indication in favor of the normal neutrino mass ordering. We show that such an indication is completely washed out if one assumes the existence of neutral-current non-standard interactions (NSI) of the flavor changing type involving the $e - τ$ flavors. This implies that the claim for a discovery of the NMO will require a careful consideration of the impact of hypothetical NSI.
hep-phhep-exPRL(2020)·38 citations
23*
Top-quark Partial Compositeness beyond the effective field theory paradigm
Diogo Buarque Franzosi🇸🇪 · Alberto Tonero🇨🇦
In theories of Partial Compositeness the top quark is a mixture of a composite and an elementary state, and as a consequence its interactions with gauge bosons are expected to deviate from those of a point-like object. At sufficiently large energies, such deviations cannot be parametrized by the leading effective field theory operators and form factors (i.e. energy dependent interactions) must be introduced. In this work, we argue that such effects might appear at relatively low energies with interesting phenomenological consequences. In analogy to the proton electromagnetic interactions, we devise a simplified phenomenological model that parametrizes the top-quark interactions with gluons in terms of two form factors. We study the implications of these interactions in top-quark and heavy top-partner pair production at a hadron collider.
hep-phJHEP(2020)·10 citations
24*
Pseudoscalar Meson Mixing, the Contribution of the Hadronic Continuum to Deviation from Factorization
N. F. Nasrallah🇱🇧
The contribution of the hadronic continuum in the QCD sum rule calculation of the parameters entering in pseudoscalar meson mixing is evaluated by making use of simple integration kernels tailored in order to practically eliminate the contribution of the hadronic continuum. This approach avoids the arbitrariness and instability inherent to previous sum rule calculations. An independent evaluation of the mixed quark gluon condensate $⟨ QGC ⟩ =$ $⟨ g q ˉ σ_{μν} \frac{λ ^{a}}{2} G_{μν}^{a} q ⟩$ which enters in the calculation is presented as well as the calculation of the K-meson decay constant $f_{K}$ to five loops.
hep-ph0 citations
25*
A modular $A_{4}$ symmetric scotogenic model
Takaaki Nomura🇰🇷 · Hiroshi Okada🇰🇷 · Oleg Popov🇰🇷
We propose a minimal extention of the Standard Model where neutrino masses are generated radiatively at one-loop level via Scotogenic scanario. The model is augmented with $A_{4}$ modular symmetry as a scotogenic and flavor symmetry. With minimal number of parameters, the model makes predictions for neutrino oscillation data, Majorana and Dirac phases, dark matter characteristics, and neutrinoless double beta decay.
hep-phPLB(2020)·119 citations
26*
RESPONSE TO Time Modulations and Amplifications in the Axion Search Experiments
Sergio Bertolucci🇮🇹 · Horst Fischer🇩🇪 · Sebastian Hofmann🇩🇪 · Marios Maroudas🇬🇷 · Yannis Semertzidis🇰🇷 · Konstantin Zioutas🇬🇷
In this short note we argue why the conclusions made by the authors of arXiv:1908.04675, related to arXiv:1805.05184 and in particular arXiv:1602.03666 given therein, are incorrect. Nevertheless, we think that the advocated Anti-Quark Nuggets are good candidates for the dark Universe, and therefore they deserve further attention.
hep-phastro-ph.CO2 citations
27*
Neutrino Mass Spectrum for Co-Bimaximal Mixings from Quantum Gravity
Bipin Singh Koranga (Department of Physics, Kirori Mal college, University of Delhi, India)🇮🇳
We consider non-renormalizable interaction term as a perturbation of the conventional neutrino mass matrix. Quantum gravitational (Planck scale )effects lead to an effective $S U (2)_{L} \times U (1)$ invariant dimension-5 Lagrangian involving neutrino and Higgs fields,On symmetry breaking, this operator gives rise to correction to the neutrino masses and mixing. The gravitational interaction $M_{X} = M_{pl}$ which gives rise to additional terms in neutrino mass matrix. We also assume that, just above the electroweak breaking scale, neutrino masses are nearly degenerate and their mixing is Co-bimaximal mixing by assuming mixing angle $θ_{13} \neq = 0 = 1 0^{o}$ , $θ_{23} = \frac{π}{4}$ , $tan θ_{12}^{2} = \frac{1 - 3 s in θ _{13}^{2}}{2} = 3 4^{o}$ and Dirac phase $δ = \pm \frac{π}{2}$ .There additional term can be considered to be perturbation of the GUT scale Co-bimaximal neutrino mass matrix. The relation consider with solar and atmospheric neutrino oscillation data predicted above GUT scale $m_{1}^{'} ≃ 0.00001 e V - 0.00003 e V$ , $m_{2}^{'} ≃ 0.00008 e V - 0.00012$ , and $m_{3}^{'} ≃ 0.000207 e V - 000320 e V$ .
hep-phInt. J. Modern Theo. Physics, 2019, 8(1)·0 citations
28*
Hybrid Color Glass Condensate and hydrodynamic description of the Relativistic Heavy Ion Collider small system scan
Bjoern Schenke🇺🇸 · Chun Shen🇺🇸 · Prithwish Tribedy🇺🇸
Multi-particle correlation observables in the Relativistic Heavy Ion Collider small system scan are computed in a framework that contains both initial state momentum anisotropies from the Color Glass Condensate effective theory and final state hydrodynamic evolution. The initial state is computed using the IP-Glasma model and coupled to viscous relativistic hydrodynamic simulations, which are followed by microscopic hadronic transport. All parameters of the calculation were previously constrained using experimental data on Au+Au collisions at the same center of mass energy. We find that the qualitative features of the experimental data, such as the system and centrality dependence of the charged hadron momentum anisotropy, can only be reproduced when final state interactions are present. On the other hand, we also demonstrate that the details of the initial state are crucially important for the quantitative description of observables in the studied small systems, as neglecting the initial transverse flow profile or the initial shear stress tensor, which contain information on the momentum anisotropy from the Color Glass Condensate, has dramatic effects on the produced final state anisotropy. We further show that the initial state momentum anisotropy is correlated with the observed elliptic flow in all small systems, with the effect increasing with decreasing multiplicity. We identify the precise measurement of $v_{2}$ in d+Au and Au+Au collisions at RHIC energy at the same multiplicity as a means to reveal effects of the initial state momentum anisotropy.
↳ nucl-thhep-phnucl-exPLB(2020)·103 citations
29*
Quantum Brownian motion of a heavy quark pair in the quark-gluon plasma
Takahiro Miura🇯🇵 · Yukinao Akamatsu🇯🇵 · Masayuki Asakawa🇯🇵 · Alexander Rothkopf🇳🇴
In this paper we study the real-time evolution of heavy quarkonium in the quark-gluon plasma (QGP) on the basis of the open quantum systems approach. In particular, we shed light on how quantum dissipation affects the dynamics of the relative motion of the quarkonium state over time. To this end we present a novel non-equilibrium master equation for the relative motion of quarkonium in a medium, starting from Lindblad operators derived systematically from quantum field theory. In order to implement the corresponding dynamics, we deploy the well established quantum state diffusion method. In turn we reveal how the full quantum evolution can be cast in the form of a stochastic non-linear Schrödinger equation. This for the first time provides a direct link from quantum chromodynamics (QCD) to phenomenological models based on non-linear Schrödinger equations. Proof of principle simulations in one-dimension show that dissipative effects indeed allow the relative motion of the constituent quarks in a quarkonium at rest to thermalize. Dissipation turns out to be relevant already at early times well within the QGP lifetime in relativistic heavy ion collisions.
↳ nucl-thhep-phnucl-exquant-phPRD(2020)·71 citations
30*
An overview of quasinormal modes in modified and extended gravity
Flora Moulin🇫🇷 · Aurélien Barrau🇫🇷 · Killian Martineau🇫🇷
As gravitational waves are now being nearly routinely measured with interferometers, the question of using them to probe new physics becomes increasingly legitimate. In this article, we rely on a well established framework to investigate how the complex frequencies of quasinormal modes are affected by different models. The tendencies are explicitly shown, for both the pulsation and the damping rate. The goal is, at this stage, purely qualitative. This opportunity is also taken to derive the Regge-Wheeler equation for general static and spherically symmetric metrics.
↳ gr-qcastro-ph.HEhep-phUniverse(2019)·39 citations
31*
Towards a theory of baryon resonances
Ulf-G. Meißner🇩🇪
In this talk, I discuss methods that allow for a systematic and model-independent calculation of the hadron spectrum. These are lattice QCD and/or its corresponding Effective Field Theories. Assorted results are shown and I take the opportunity to discuss some misconceptions often found in the literature.
↳ nucl-thhep-exhep-lathep-ph+1EPJ Web Conf.(2020)·5 citations
32*
SU(2) non-Abelian gauge field theory in one dimension on digital quantum computers
Natalie Klco🇺🇸 · Jesse R. Stryker🇺🇸 · Martin J. Savage🇺🇸
An improved mapping of one-dimensional SU(2) non-Abelian gauge theory onto qubit degrees of freedom is presented. This new mapping allows for a reduced unphysical Hilbert space. Insensitivity to interactions within this unphysical space is exploited to design more efficient quantum circuits. Local gauge symmetry is used to analytically incorporate the angular momentum alignment, leading to qubit registers encoding the total angular momentum on each link. The results of a multi-plaquette calculation on IBM's quantum hardware are presented.
↳ quant-phhep-lathep-phnucl-thPRD(2020)·325 citations
33*
Neutrino Fluence from Gamma-Ray Bursts: Off-Axis View of Structured Jets
Markus Ahlers🇩🇰 · Lea Halser🇩🇰
We investigate the expected high-energy neutrino fluence from internal shocks produced in the relativistic outflow of gamma-ray bursts. Previous model predictions have primarily focussed on on-axis observations of uniform jets. Here we present a generalization to account for arbitrary viewing angles and jet structures. Based on this formalism, we provide an improved scaling relation that expresses off-axis neutrino fluences in terms of on-axis model predictions. We also find that the neutrino fluence from structured jets can exhibit a strong angular dependence relative to that of gamma-rays and can be far more extended. We examine this behavior in detail for the recent short gamma-ray burst GRB 170817A observed in coincidence with the gravitational wave event GW170817.
↳ astro-ph.HEhep-exhep-phMNRAS(2019)·15 citations
34*
Oscillating scalar fields and the Hubble tension: a resolution with novel signatures
Tristan L. Smith🇺🇸 · Vivian Poulin🇫🇷 · Mustafa A. Amin🇺🇸
We present a detailed investigation of a sub-dominant oscillating scalar field ('early dark energy', EDE) in the context of resolving the Hubble tension. Consistent with earlier work, but without relying on fluid approximations, we find that a scalar field frozen due to Hubble friction until $log_{10} (z_{c}) \sim 3.5$ , reaching $ρ_{EDE} (z_{c}) / ρ_{tot} \sim 10$ %, and diluting faster than matter afterwards can bring cosmic microwave background (CMB), baryonic acoustic oscillations, supernovae luminosity distances, and the late-time estimate of the Hubble constant from the SH0ES collaboration into agreement. A scalar field potential which scales as $V (ϕ) \propto ϕ^{2 n}$ with $2 ≲ n ≲ 3.4$ around the minimum is preferred at the 68% confidence level, and the {\em Planck} polarization places additional constraints on the dynamics of perturbations in the scalar field. In particular, the data prefers a potential which flattens at large field displacements. An MCMC analysis of mock data shows that the next-generation CMB observations (i.e., CMB-S4) can unambiguously detect the presence of the EDE at very high significance. This projected sensitivity to the EDE dynamics is mainly driven by improved measurements of the $E$ -mode polarization. We also explore new observational signatures of EDE scalar field dynamics: (i) We find that depending on the strength of the tensor-to-scalar ratio, the presence of the EDE might imply the existence of isocurvature perturbations in the CMB. (ii) We show that a strikingly rapid, scale-dependent growth of EDE field perturbations can result from parametric resonance driven by the anharmonic oscillating field for $n \approx 2$ . This instability and ensuing potentially nonlinear, spatially inhomogenoues, dynamics may provide unique signatures of this scenario.
↳ astro-ph.COgr-qchep-phPRD(2020)·422 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.