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Trace element geochemistry of coarse‐grained angrites from Northwest Africa: Implications for their petrogenesis on the angrite parent body Meteorit. Planet. Sci. (IF 2.863) Pub Date : 2021-03-03 Matthew E. Sanborn; Meenakshi Wadhwa
The angrites are a class of achondrites that encompass a wide range of igneous textures from quenched, volcanic, and subvolcanic stones to slowly cooled, plutonic rocks. The compositions of the various geochemical reservoirs generating this variety of rocks have not been investigated fully because historically the numbers and masses of angrites available for study have been quite small. However, the
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Vortex sheet turbulence as solvable string theory Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-03-02 Alexander Migdal
We study steady vortex sheet solutions of the Navier–Stokes in the limit of vanishing viscosity at fixed energy flow. We refer to this as the turbulent limit. These steady flows correspond to a minimum of the Euler Hamiltonian as a functional of the tangent discontinuity of the local velocity parametrized as Δv→t=∇→Γ. This observation means that the steady flow represents the low-temperature limit
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Exploration of the coupling between thrust and interference in Taiji-1 Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-27 Juan Wang; Ran Yang; Yu Niu; On behalf of The Taiji Scientific Collaboration
As the first technology verification satellite of the space-based gravitational wave detection in China, Taiji-1 has tested the high-precision space laser interferometer, the inertial sensor, the micro thruster and the hyperstatic satellite platform in orbit. The micro thruster plays an important role in the micro propulsion system. The purposes of the research are to investigate the relationship between
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Adaptive preload controller design and analysis for electrostatic suspension system Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-27 Yukun Wang; Zhi Wang; On behalf of The Taiji Scientific Collaboration
The electrostatic suspension control system (ESCS) is the core component of the inertial sensor in space gravitational wave detection. To adapt to the changes in orbit environment and satellite platform vibration, the test mass stable is kept in the center of the electrode cage, the ESCS requires high-precision parameters calibration and high-stability verification of the control system. This paper
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A tale of three diagonalizations Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-22 Howard E. Haber
In addition to the diagonalization of a normal matrix by a unitary similarity transformation, there are two other types of diagonalization procedures that sometimes arise in quantum theory applications — the singular value decomposition and the Autonne–Takagi factorization. In this pedagogical review, each of these diagonalization procedures is performed for the most general 2×2 matrices for which
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Pair production of heavy neutrinos in next-to-leading order QCD at the hadron colliders in the inverse seesaw framework Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-25 Arindam Das
The explanation of the small neutrino mass can be depicted using some handsome models like type-I and inverse seesaw where the Standard Model gauge singlet heavy right-handed neutrinos are deployed. The common thing in these two models is a lepton number violating parameter, however, its order of magnitude creates a striking difference between them making the nature of the right-handed heavy neutrinos
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Wormhole solutions in modified f(R,φ,X) gravity Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-25 M. Farasat Shamir; Adnan Malik; G. Mustafa
This work aims to investigate the wormhole solutions in the background of f(R,φ,X) theory of gravity, where R is Ricci scalar, φ is scalar potential, and X is the kinetic term. We consider spherically symmetric static space–time for exploring the wormhole geometry with anisotropic fluid. For our current analysis, we consider a particular equation of state parameter to study the behavior of traceless
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Precision physics of muonic ions of lithium, beryllium and boron Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-16 A. E. Dorokhov; R. N. Faustov; A. P. Martynenko; F. A. Martynenko
The problem of determining the main parameters of light nuclei from precision atomic spectroscopy is considered. Within the framework of the quasipotential method in quantum electrodynamics, the energy interval (2S−1S) in muonic ions of lithium, beryllium and boron is calculated. Corrections of orders α3÷α6, which are determined by relativistic effects, effects of vacuum polarization, nuclear structure
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Reflection identities of harmonic sums and pole decomposition of BFKL eigenvalue Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-22 Mohammad Joubat; Alex Prygarin
We analyze the recent results of next-to-next-to-leading (NNLO) singlet BFKL eigenvalue in N=4 SYM written in terms of harmonic sums. The nested harmonic sums building known NNLO BFKL eigenvalue for specific values of the conformal spin have poles at negative integers. We sort the harmonic sums according to the complexity with respect to their weight and depth and use their pole decomposition in terms
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Hyperbolic worldsheets and worldlines of null Cartan curves in de Sitter 3-space Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-22 Qingxin Zhou; Jingbo Xu; Zhigang Wang
The hyperbolic worldsheets and the hyperbolic worldline generated by null Cartan curves are defined and their geometric properties are investigated. As applications of singularity theory, the singularities of the hyperbolic worldsheets and the hyperbolic worldline are classified by using the approach of the unfolding theory in singularity theory. It is shown that under appropriate conditions, the hyperbolic
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Accurate study from adaptive perturbation method Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-22 Chen-Te Ma
The adaptive perturbation method decomposes a Hamiltonian by the diagonal elements and nondiagonal elements of the Fock state. The diagonal elements of the Fock state are solvable but can contain the information about coupling constants. We study the harmonic oscillator with the interacting potential, λ1x4/6+λ2x6/120, where λ1 and λ2 are coupling constants, and x is the position operator. In this study
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Barrow HDE model for statefinder diagnostic in FLRW universe Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-22 Anirudh Pradhan; Archana Dixit; Vinod Kumar Bhardwaj
We have analyzed the Barrow holographic dark energy (BHDE) in the framework of flat FLRW universe by considering the various estimations of Barrow exponent △. Here, we define BHDE, by applying the usual holographic principle at a cosmological system, for utilizing the Barrow entropy rather than the standard Bekenstein–Hawking. To understand the recent accelerated expansion of the universe, consider
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Casimir effect in a Schwarzschild-like wormhole spacetime Int. J. Mod. Phys. D (IF 2.154) Pub Date : 2021-02-25 A. C. L. Santos; C. R. Muniz; L. T. Oliveira
In this paper, we investigate the role of gravito-inertial effects on the Casimir energy of a massless scalar field confined between two parallel plates orbiting a static and zero tidal Schwarzschild-like wormhole, at zero temperature. Firstly, we obtain the metric in isotropic coordinates, finding the allowed angular velocities and the circular orbit radii for a material particle as well as for the
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Intrinsically symmetric cosmological model in the presence of dissipative fluids Int. J. Mod. Phys. D (IF 2.154) Pub Date : 2021-02-25 Eduardo Bittencourt; Leandro Gomes; Grasiele Santos
Based upon the intrinsic symmetries approach to inhomogeneous cosmologies, we propose an exact solution to Einstein’s field equations where the spatial sections are flat and the source is a nonperfect fluid such that the dissipative terms can be written in terms of spatial gradients of the energy density under a suitable choice of the coordinate system. It is shown through the calculation of the luminosity
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Polarization tensor in de Sitter gauge gravity Int. J. Mod. Phys. D (IF 2.154) Pub Date : 2021-02-25 R. Raziani; M. V. Takook
The gauge theory of the de Sitter group, SO(1,4), in the ambient space formalism has been considered in this paper. This method is important to construction of the de Sitter super-conformal gravity and Quantum gravity. 10 gauge vector fields are needed which correspond to 10 generators of the de Sitter group. Using the gauge-invariant Lagrangian, the field equations of these vector fields have been
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α-Attractors and reheating in a class of Galileon inflation Int. J. Mod. Phys. D (IF 2.154) Pub Date : 2021-02-25 R. Shojaee; K. Nozari; F. Darabi
We study cosmological inflation in a Galileon inflationary model with the E-model potential to find possible α-attractors. First, we calculate evolution of the perturbations in our setup. By adopting E-model potential, we show that values of the scalar spectral index and tensor-to-scalar ratio are universal. Also, we consider the reheating phase after inflation in this model. We compare the results
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Constraints for the running index independent of the parameters of the model Int. J. Mod. Phys. D (IF 2.154) Pub Date : 2021-02-25 Gabriel Germán
By writing the running of the scalar spectral index completely in terms of the scalar index ns and the tensor-to-scalar ratio r we are able to impose constraints to models of inflation which are independent of the parameters of the model in question. We write analytical expressions for the running index of Natural Inflation, two models of the type Mutated Hilltop Inflation and the Starobinsky model
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The phasemeter of Taiji-1 experimental satellite Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-25 Zi-Ren Luo; Tao Yu; He-Shan Liu; On behalf of The Taiji Scientific Collaboration
Taiji-1 is the first demonstrated experimental satellite of Taiji program in China. Phasemeter is one of the key components of the laser interferometer which is responsible for phase extraction of the heterodyne signals. In this paper, we present the architecture and implementation of Taiji-1 phasemeter. The DPLL architecture is used in Taiji-1 which is generally regarded as the best choice for space
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No radiative corrections to the Carroll–Field–Jackiw term beyond one-loop order Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-25 L. C. T. Brito; J. C. C. Felipe; A. Yu. Petrov; A. P. Baêta Scarpelli
We demonstrate explicitly the absence of the quantum corrections to the Carroll–Field–Jackiw (CFJ) term beyond one-loop within the Lorentz-breaking CPT-odd extension of QED. The proof holds within two prescriptions of quantum calculations, with the axial vector in the fermion sector treated either as a perturbation or as a contribution in the exact propagator of the fermion field.
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Study of the Υ(1S) → DP decays Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-25 Yueling Yang; Mingfei Duan; Junliang Lu; Jinshu Huang; Junfeng Sun
Inspired by the potential prospects of high-luminosity dedicated colliders and the high enthusiasms in searching for new physics in the flavor sector at the intensity frontier, the Υ(1S)→D−π+, D̄0π0 and Ds−K+ weak decays are studied with the perturbative QCD approach. It is found within the standard model that the branching ratios for the concerned processes are tiny, about 𝒪(10−18), and far beyond
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The Mechanical Properties of Chelyabinsk LL5 Chondrite Under Compression and Tension Earth Moon Planets (IF 0.609) Pub Date : 2021-02-27 Dmitry Zaytsev, Elijah N. Borodin, A. E. Dudorov, P. Panfilov
The mechanical properties of Chelyabinsk LL5 chondrite (Chelyabinsk meteorite) were studied by uniaxial compression and diametral compression/indirect tension test. Twenty cylindrical samples, 10 for compression and 10 for tension, with the diameter 3.3 mm and 1.65 mm in height have been prepared for testing. It was shown that the strength of the tested samples under compression almost 45 times greater
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CM carbonaceous chondrite falls and their terrestrial alteration Meteorit. Planet. Sci. (IF 2.863) Pub Date : 2021-01-18 Martin R. Lee; Luke Daly; Cameron Floyd; Pierre‐Etienne Martin
The CM carbonaceous chondrites provide unique insights into the composition of the protoplanetary disk, and the accretion and geological history of their parent C‐complex asteroid(s). Of the hundreds of CMs that are available for study, the majority are finds and so may have been compromised by terrestrial weathering. Nineteen falls have been recovered between 1838 and 2020, and there is a hint of
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An unusual porous, cryptocrystalline forsterite chondrule in Murchison Meteorit. Planet. Sci. (IF 2.863) Pub Date : 2020-12-28 Michael Zolensky; Tomoki Nakamura; James Martinez; Yuma Enokido
We describe a fragmented cryptocrystalline chondrule consisting solely of forsterite (Fo98) in the Murchison CM2 chondrite, with a peculiar porous texture of enigmatic origin.
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Comparison of the Murchison CM2 and Allende CV3 chondrites Meteorit. Planet. Sci. (IF 2.863) Pub Date : 2021-02-09 Kim V. Fendrich; Denton S. Ebel
The size distribution, abundance, and physical and chemical characteristics of chondritic inclusions are key features that define the chondrite groups. We present statistics on the size and abundance of the macroscopic components (inclusions) in the Murchison (CM2) and Allende (CV3) chondrites and measure their general chemical trends using established X‐ray mapping techniques. This study provides
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Supermassive primordial black holes at high redshifts Int. J. Mod. Phys. D (IF 2.154) Pub Date : 2021-02-23 V. K. Dubrovich; Yu. N. Eroshenko; S. I. Grachev
We consider some properties and possible observational manifestations of the very heavy primordial black holes (PBHs), with masses ∼(109−1010)M⊙. These black holes should be surrounded by the dense dark matter and baryonic halos even at early cosmological epochs. There are mechanisms as for radiation emission in the centers due to accretion and for deep absorption of relic radiation at the periphery
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What happens for the BTZ black hole solution in dilaton f(R)-gravity? Int. J. Mod. Phys. D (IF 2.154) Pub Date : 2021-02-23 Younes Younesizadeh; Ali Hassan Ahmed; Amir A. Ahmad; Feyzollah Younesizadeh; Morad Ebrahimkhas
In this work, we obtain the black hole solutions in the dilaton f(R)-gravity (R is not considered as a constant here) and investigate their thermodynamics especially phase transition and critical behavior in the anti-de Sitter (AdS) extended phase-space. We obtain the exact Banados, Teitelboim and Zanelli (BTZ) counterpart solutions in dilaton f(R)-gravity which is the basis of our work. We also obtain
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Distinct classes of compact stars based on geometrically deduced equations of state Int. J. Mod. Phys. D (IF 2.154) Pub Date : 2021-02-23 A. C. Khunt; V. O. Thomas; P. C. Vinodkumar
We have computed the properties of compact objects like neutron stars based on equation of state (EOS) deduced from a core–envelope model of superdense stars. Such superdense stars have been studied by solving Einstein’s equation based on pseudo-spheroidal and spherically symmetric spacetime geometry. The computed star properties are compared with those obtained based on nuclear matter EOSs. From the
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Constraining unparticle-inspired model parameters using dwarf stars Int. J. Mod. Phys. D (IF 2.154) Pub Date : 2021-02-23 Mohamed Moussa
The unparticle-inspired model of gravity suggested by Georgi is based on that the standard model (SM) may contain a massive but scale invariant particles, which can be exchanged between SM massive particles, leading to a new force called ungravity. This would add a perturbed term to the Newtonian law of gravity at low energy. We use the minimum mass of hydrogen burning (MMHB) to constrain the relevant
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Suppression of electroweak instanton processes in high-energy collisions Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-24 Valentin V. Khoze; Daniel L. Milne
Electroweak instantons are a prediction of the Standard Model and have been studied in great detail in the past although they have not been observed. Earlier calculations of the instanton production cross-section at colliders revealed that it was exponentially suppressed at low energies, but may grow large at energies (much) above the sphaleron mass. Such calculations faced difficulty in the breakdown
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The pilot of Taiji program — From the ground to Taiji-2 Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-22 The Taiji Scientific Collaboration
The Taiji-1 satellite is a pilot satellite mission of Taiji program, which is used to verify Taiji’s key technology and also to testify the feasibility of Taiji roadmap. Taiji-1 was launched on 31st August 2019 and its designed mission was completed. The results of Taiji-1 first scientific run are briefly introduced. A detailed analysis on how Taiji-1 can bridge the gap between ground experiment and
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Successful application of optical bench in Taiji-1 laser interferometer Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-22 Wei Sha; Chao Fang; Yu Niu; On behalf of The Taiji Scientific Collaboration
As an important part of laser interferometry system, optical bench is one of the core technologies for the detection of spaceborne gravitational waves. As the first step of the space Taiji program, Taiji-1 provides the measurement accuracy of laser interferometry system better than 100 pm/Hz1/2(@10 mHz–1 Hz). Taiji-1 is required to be able to track the motion of test mass in inertial sensor. According
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In-orbit performance of the laser interferometer of Taiji-1 experimental satellite Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-22 He-Shan Liu; Zi-Ren Luo; Wei Sha; On behalf of The Taiji Scientific Collaboration
Taiji-1, which is the first experimental satellite for space gravitational wave detection in China, relies on key technologies which include the laser interferometer, the gravitational reference sensor (GRS), the micro-thruster and the satellite platform. Similarly to the Laser Interferometer Space Antenna (LISA) pathfinder, except for the science interferometer, the optical bench (OB) of Taiji-1 contains
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Renormalization in Minkowski space–time Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-22 Imola Steib; Sándor Nagy; János Polonyi
The multiplicative and the functional renormalization group methods are applied for the four-dimensional scalar theory in Minkowski space–time. It is argued that the appropriate choice of the subtraction point is more important in Minkowski than in Euclidean space–time. The parameters of the cutoff theory, defined by a subtraction point in the quasi-particle domain, are complex due to the mass-shell
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Primordial black holes from metric preheating: mass fraction in the excursion-set approach J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-19 Pierre Auclair; Vincent Vennin
We calculate the mass distribution of Primordial Black Holes (PBHs) produced during metric preheating. After inflation, the oscillations of the inflaton at the bottom of its potential source a parametric resonant instability for small-scale scalar perturbations, that may collapse into black holes. After reviewing in a pedagogical way different techniques that have been developed in the literature to
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Where do IceCube neutrinos come from? Hints from the diffuse gamma-ray flux J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-18 Antonio Capanema; Arman Esmaili; Pasquale Dario Serpico
Despite the spectacular discovery of an astrophysical neutrino flux by IceCube in 2013, its origin remains a mystery. Whatever its sources, we expect the neutrino flux to be accompanied by a comparable gamma-ray flux. These photons should be degraded in energy by electromagnetic cascades and contribute to the diffuse GeV–TeV flux precisely measured by the Fermi-LAT. Population studies have also permitted
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Towards ending the partial sky E-B ambiguity in CMB observations J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-18 Shamik Ghosh; Jacques Delabrouille; Wen Zhao; Larissa Santos
A crucial problem for partial sky analysis of CMB polarization is the E-B leakage problem. Such leakage arises from the presence of `ambiguous' modes that satisfy properties of both E and B modes. Solving this problem is critical for primordial polarization B mode detection in partial sky CMB polarization experiments. In this work we introduce a new method for reducing the leakage. We demonstrate that
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Gravitational Wave mergers as tracers of Large Scale Structures J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-18 S. Libanore; M. C. Artale; D. Karagiannis; M. Liguori; N. Bartolo; Y. Bouffanais; N. Giacobbo; M. Mapelli; S. Matarrese
Clustering measurements of Gravitational Wave (GW) mergers in Luminosity Distance Space can be used in the future as a powerful tool for Cosmology. We consider tomographic measurements of the Angular Power Spectrum of mergers both in an Einstein Telescope-like detector network and in some more advanced scenarios (more sources, better distance measurements, better sky localization). We produce Fisher
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Quartic hilltop inflation revisited J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-18 Gabriel Germán
We implement a procedure by which the parameters present in the potential of Quartic Hilltop Inflation (QHI) are eliminated in favor of the scalar spectral index ns and the tensor-to-scalar ratio r. By doing this it is posible to obtain in a straightforward and simple way the equations of a previous analysis where an analytical treatment of QHI in the large field limit is given. This procedure also
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The MESS of the CMB J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-17 Manuel Alejandro Jaramillo Rodrǵuez; Antonio Enea Romano; Sergio Andrés Vallejo-Peña
We analyze cosmic microwave background (CMB) data taking into account the effects of a momentum dependent effective sound speed (MESS) . This approach allows to study the effects of primordial entropy perturbations in a model independent way, and its implementation requires a minimal modification of existing CMB fitting numerical codes developed for single scalar field models. We adopt a phenomenological
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Gravitational wave signatures from discrete flavor symmetries J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-17 Graciela B. Gelmini; Silvia Pascoli; Edoardo Vitagliano; Ye-Ling Zhou
Non-Abelian discrete symmetries have been widely used to explain the patterns of lepton masses and flavor mixing. In these models, a given symmetry is assumed at a high scale and then is spontaneously broken by scalars (the flavons), which acquire vacuum expectation values. Typically, the resulting leading order predictions for the oscillation parameters require corrections in order to comply with
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Impact of loop-induced processes on the boosted dark matter interpretation of the XENON1T excess J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-17 Luigi Delle Rose; Gert Hütsi; Carlo Marzo; Luca Marzola
We consider the boosted dark matter solution of the XENON1T excess to constrain the framework through loop-generated processes. The interaction of the boosted dark matter component, which sources the signal, effectively couples the cold dark matter background to the electrons, making it potentially visible in the electron recoil searches. Similarly, once the radiative corrections due to the Standard
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Origin of the degassing pipes at the Ries impact structure and implications for impact‐induced alteration on Mars and other planetary bodies Meteorit. Planet. Sci. (IF 2.863) Pub Date : 2021-02-15 Christy Caudill; Gordon R. Osinski; Rebecca N. Greenberger; Livio L. Tornabene; Fred J. Longstaffe; Roberta L. Flemming; Bethany L. Ehlmann
The impact melt‐bearing breccias at the Ries impact structure, Germany, host degassing pipes: vertical structures that are inferred to represent conduits along which gases and fluids escaped to the surface, consistent with hydrothermal activity that occurs soon after an impact event. Although the presence of degassing pipes has been recognized within the well‐preserved and long‐studied ejecta deposits
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Mineralogy, petrology, geochemistry, and chronology of the Murrili (H5) meteorite fall: The third recovered fall from the Desert Fireball Network Meteorit. Planet. Sci. (IF 2.863) Pub Date : 2021-02-12 S. Anderson; G. K. Benedix; L. V. Forman; L. Daly; R. C. Greenwood; I. A. Franchi; J. M. Friedrich; R. Macke; S. Wiggins; D. Britt; J. M. Cadogan; M. M. M. Meier; C. Maden; H. Busemann; K. C. Welten; M. W. Caffee; F. Jourdan; C. Mayers; T. Kennedy; B. Godel; L. Esteban; K. Merigot; A. W. R. Bevan; P. A. Bland; J. Paxman; M. C. Towner; M. Cupak; E. K. Sansom; R. Howie; H. Devillepoix; T. Jansen‐Sturgeon;
Murrili, the third meteorite recovered by the Desert Fireball Network, is analyzed using mineralogy, oxygen isotopes, bulk chemistry, physical properties, noble gases, and cosmogenic radionuclides. The modal mineralogy, bulk chemistry, magnetic susceptibility, physical properties, and oxygen isotopes of Murrili point to it being an H5 ordinary chondrite. It is heterogeneously shocked (S2–S5), depending
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Cosmic ray positrons from compact binary millisecond pulsars J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-15 M. Linares; M. Kachelrieß
A new population of neutron stars has emerged during the last decade: compact binary millisecond pulsars (CBMSPs). Because these pulsars and their companion stars are in tight orbits with typical separations of 1011 cm, their winds interact strongly forming an intrabinary shock. Electron-positron pairs reaccelerated at the shock can reach energies of about 10 TeV, which makes this new population a
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High-order corrections to inflationary perturbation spectra in quantum gravity J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-15 Damiano Anselmi
We compute the inflationary perturbation spectra and the quantity r+8nT to the next-to-next-to-leading log order in quantum gravity with purely virtual particles (which means the theory R+R2+C2 with the fakeon prescription/projection for C2). The spectra are functions of the inflationary running coupling α (1/k) and satisfy the cosmic renormalization-group flow equations, which determine the tilts
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The self-organized critical multiverse J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-15 Guram Kartvelishvili; Justin Khoury; Anushrut Sharma
Recently a dynamical selection mechanism for vacua based on search optimization was proposed in the context of false-vacuum eternal inflation on the landscape. The search algorithm, defined by local vacuum transitions, is optimal in regions of the landscape where the dynamics are tuned at criticality, with de Sitter vacua having an average lifetime of order their Page time. The purpose of this paper
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The flat sky approximation to galaxy number counts J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-15 William L. Matthewson; Ruth Durrer
We derive and test an approximation for the angular power spectrum of galaxy number counts in the flat sky limit. The standard density and redshift space distortion (RSD) terms in the resulting approximation are distinct to the Limber approximation, providing an accurate result for multipoles as low as ℓ ≃ 10, where the corresponding Limber approximation is completely inaccurate. At equal redshift
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A connection between linearized Gauss–Bonnet gravity and classical electrodynamics II: Complete dual formulation Int. J. Mod. Phys. D (IF 2.154) Pub Date : 2021-02-10 Mark Robert Baker
In a recent publication, a procedure was developed which can be used to derive completely gauge invariant models from general Lagrangian densities with N order of derivatives and M rank of tensor potential. This procedure was then used to show that unique models follow for each order, namely classical electrodynamics for N=M=1 and linearized Gauss–Bonnet gravity for N=M=2. In this paper, the nature
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Shock deformation in zircon grains from the Mien impact structure, Sweden Meteorit. Planet. Sci. (IF 2.863) Pub Date : 2021-02-12 Josefin Martell; Carl Alwmark; Sanna Holm‐Alwmark; Paula Lindgren
Recognition of impact‐induced deformation of minerals is crucial for the identification and confirmation of impact structures as well as for the understanding of shock wave behavior and crater formation. Shock deformed mineral grains from impact structures can also serve as important geochronometers, precisely dating the impact event. We investigated zircon grains from the Mien impact structure in
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Equation of states in the curved spacetime of spherical degenerate stars J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-12 Golam Mortuza Hossain; Susobhan Mandal
In the study of spherical degenerate stars such as neutron stars, general relativistic effects are incorporated by using Tolman-Oppenheimer-Volkoff equations to describe their interior spacetime. However, the equation of states employed in such studies are invariably computed in flat spacetime. We show that the equation of states computed in the curved spacetime of these stars depend explicitly on
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Searches for neutrinos from cosmic-ray interactions in the Sun using seven years of IceCube data J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-12 M.G. Aartsen; M. Ackermann; J. Adams; J.A. Aguilar; M. Ahlers; M. Ahrens; C. Alispach; K. Andeen; T. Anderson; I. Ansseau; G. Anton; C. Argüelles; J. Auffenberg; S. Axani; P. Backes; H. Bagherpour; X. Bai; A. Balagopal V.; A. Barbano; S.W. Barwick; B. Bastian; V. Baum; S. Baur; R. Bay; J.J. Beatty; K.-H. Becker; J. Becker Tjus; S. BenZvi; D. Berley; E. Bernardini; D.Z. Besson; G. Binder; D. Bindig;
Cosmic-ray interactions with the solar atmosphere are expected to produce particle showers which in turn produce neutrinos from weak decays of mesons. These solar atmospheric neutrinos (SAνs) have never been observed experimentally. A detection would be an important step in understanding cosmic-ray propagation in the inner solar system and the dynamics of solar magnetic fields. SAνs also represent
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Black hole shadows in M-theory scenarios Int. J. Mod. Phys. D (IF 2.154) Pub Date : 2021-02-09 A. Belhaj; M. Benali; A. El Balali; W. El Hadri; H. El Moumni; E. Torrente-Lujan
We study the shadows of four-dimensional black holes in M-theory inspired models. We first inspect the influence of M2-branes on such optical aspects for nonrotating solutions. In particular, we show that the M2-brane number can control the circular shadow size. This geometrical behavior is distorted for rotating solutions exhibiting cardioid shapes in certain moduli space regions. Implementing a rotation
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Impact of f(R,T) gravity in evolution of charged viscous fluids Int. J. Mod. Phys. D (IF 2.154) Pub Date : 2021-02-09 I. noureen; Usman-ul-Haq; S. A. Mardan
In this work, the evolution of spherically symmetric charged anisotropic viscous fluids is discussed in framework of f(R,T) gravity. In order to conduct the analysis, modified Einstein Maxwell field equations are constructed. Nonzero divergence of modified energy momentum tensor is taken that implicates dynamical equations. The perturbation scheme is applied to dynamical equations for stability analysis
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Electromagnetic bursts from mergers of oscillons in axion-like fields J. Cosmol. Astropart. Phys. (IF 5.21) Pub Date : 2021-02-11 Mustafa A. Amin; Zong-Gang Mou
We investigate the bursts of electromagnetic and scalar radiation resulting from the collision, and merger of oscillons made from axion-like particles using 3+1 dimensional lattice simulations of the coupled axion-gauge field system. The radiation into photons is suppressed before the merger. However, it becomes the dominant source of energy loss after the merger if a resonance condition is satisfied
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Analyticity properties of scattering amplitude in theories with compactified space dimensions: The proof of dispersion relations Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-08 Jnanadeva Maharana
The analyticity properties of the scattering amplitude for a massive scalar field are reviewed in this paper where the space–time geometry is R3,1⊗S1, i.e. one spatial dimension is compact. Khuri investigated the analyticity of scattering amplitude in a nonrelativistic potential model in three dimensions with an additional compact dimension. He showed that under certain circumstances, the forward amplitude
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Axially symmetric Petrov type II general space–time and closed timelike curves Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-02 Bidyut Bikash Hazarika
We present a Petrov type II general space–time which violates causality in the sense that it allows for the formation of closed timelike curves that appear after a definite instant of time. The metric, which is axially symmetric, admits an expansion-free, twist-free and shear-free null geodesic congruence. From the general metric, we obtain two particular type II metrics. One is a vacuum solution while
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Effects of extended uncertainty principle on the relativistic Coulomb potential Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-02 B. Hamil; M. Merad; T. Birkandan
The relativistic bound-state energy spectrum and the wave functions for the Coulomb potential are studied for de Sitter and anti-de Sitter spaces in the context of the extended uncertainty principle. Klein–Gordon and Dirac equations are solved analytically to obtain the results. The electron energies of hydrogen-like atoms are studied numerically.
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On the gauge transformation for the rotation of the singular string in the Dirac monopole theory Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-05 Xiao-Yin Pan; Yin Chen; Yu-Qi Li; Aaron G. Kogan; Juhao Wu
In the Dirac theory of the quantum-mechanical interaction of a magnetic monopole and an electric charge, the vector potential is singular from the origin to infinity along a certain direction — the so-called Dirac string. Imposing the famous quantization condition, the singular string attached to the monopole can be rotated arbitrarily by a gauge transformation, and hence is not physically observable
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Spectrum of the q-Schrödinger equation by means of the variational method based on the discrete q-Hermite I polynomials Int. J. Mod. Phys. A (IF 1.486) Pub Date : 2021-02-05 Mehmet Turan; Rezan Sevinik Adıgüzel; Ayşe Doğan Çalışır
In this work, the q-Schrödinger equations with symmetric polynomial potentials are considered. The spectrum of the model is obtained for several values of q, and the limiting case as q→1 is considered. The Rayleigh–Ritz variational method is adopted to the system. The discrete q-Hermite I polynomials are handled as basis in this method. Furthermore, the following potentials with numerous results are
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