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Linear Stability Analysis of Relativistic Magnetized Jets: The Minimalist Approach Universe (IF 2.9) Pub Date : 2024-04-17 Nektarios Vlahakis
A minimalist approach to the linear stability problem in fluid dynamics is developed that ensures efficiency by utilizing only the essential elements required to find the eigenvalues for given boundary conditions. It is shown that the problem is equivalent to a single first-order ordinary differential equation, and that studying the argument of the unknown complex function in the eigenvalue space is
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Special Issue on Modified Gravity Approaches to the Tensions of ΛCDM: Goals and Highlights Universe (IF 2.9) Pub Date : 2024-04-18 Eleonora Di Valentino, Leandros Perivolaropoulos, Jackson Levi Said
The standard cosmological model, known as ΛCDM, has been remarkably successful in providing a coherent and predictive framework for understanding the Universe’s evolution, its large-scale structure, and cosmic microwave background (CMB) radiation [...]
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The Statistical Analysis of Exoplanet and Host Stars Based on Multi-Satellite Data Observations Universe (IF 2.9) Pub Date : 2024-04-16 Yanke Tang, Xiaolu Li, Kai Xiao, Ning Gai, Shijie Li, Futong Dong, Yifan Wang, Yang Gao
In recent years, the rapid development of exoplanet research has provided us with an opportunity to better understand planetary systems in the universe and to search for signs of life. In order to further investigate the prevalence of habitable exoplanets and to validate planetary formation theories, as well as to comprehend planetary evolution, we have utilized confirmed exoplanet data obtained from
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Causal Structure in Spin Foams Universe (IF 2.9) Pub Date : 2024-04-14 Eugenio Bianchi, Pierre Martin-Dussaud
The metric field of general relativity is almost fully determined by its causal structure. Yet, in spin foam models of quantum gravity, the role played by the causal structure is still largely unexplored. The goal of this paper is to clarify how causality is encoded in such models. The quest unveils the physical meaning of the orientation of the two-complex and its role as a dynamical variable. We
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Small-Scale Cosmology Independent of the Standard Model Universe (IF 2.9) Pub Date : 2024-04-13 Georgy I. Burde
`Small-scale cosmology’ is a theory designed to incorporate the linear redshift versus distance relation, which is inferred from observations, into the theoretical framework independent of the global Robertson–Walker–Friedman (RWF)-type models. The motivation behind this is that the RWF cosmological models, based on the assumptions of homogeneity and a constant matter density, as well as the concept
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Statistical Study on the Q Parameter Based on Parkes Data Universe (IF 2.9) Pub Date : 2024-04-11 Xu Zhu, Hui Liu, Xinji Wu, Rushuang Zhao, Qijun Zhi, Shijun Dang, Lunhua Shang, Shuo Xiao, Hongwei Xu, Weilan Li, Ruwen Tian, Shidong Wang, Zefeng Tu
Using the rotating vector model (RVM) and aiming to constrain the value of the magnetic inclination angle (α), we perform a least-squares fit on the linearly polarized position angles of 125 pulsars from Parkes 64 m archive data at 1400 MHz. Subsequently, a statistical analysis of the normalized Q parameters is carried out. Furthermore, based on the Q-parameter, we provide a further understanding of
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Revisiting a Realistic Intersecting D6-Brane with Modified Soft SUSY Terms Universe (IF 2.9) Pub Date : 2024-04-11 Imtiaz Khan, Waqas Ahmed, Tianjun Li, Shabbar Raza
Because there are a few typos in the supersymmetry-breaking sfermion masses and trilinear soft term, regarding the current Large Hadron Collider (LHC) and dark matter searches, we revisit a three-family Pati–Salam model based on intersecting D6-branes in Type IIA string theory on a T6/(Z2×Z2) orientifold with a realistic phenomenology. We study the viable parameter space and discuss the spectrum consistent
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Upper Bound of Barrow Entropy Index from Black Hole Fragmentation Universe (IF 2.9) Pub Date : 2024-04-11 Jiayi Xia, Yen Chin Ong
Both classical and quantum arguments suggest that if Barrow entropy is correct, its index δ must be energy-dependent, which would affect the very early universe. Based on thermodynamic stability that sufficiently large black holes should not fragment, we argue that Barrow entropy correction must be small, except possibly at the Planckian regime. Furthermore, the fact that a solar mass black hole does
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A New Solution of the Pulsar Equation Universe (IF 2.9) Pub Date : 2024-04-12 Ioannis Contopoulos, Ioannis Dimitropoulos, Dimitris Ntotsikas, Konstantinos N. Gourgouliatos
We present the first new type of solution of the pulsar equation since 1999. In it, the whole magnetosphere is confined inside the light cylinder and an electrically charged layer wraps around it and holds it together. The reason this new solution has never been obtained before is that all current time-dependent simulations are initialized with a vacuum dipole configuration that extends to infinity;
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Minkowskian Approach to the Pseudorange Navigation Equations Universe (IF 2.9) Pub Date : 2024-04-12 Ramón Serrano Montesinos, Juan Antonio Morales-Lladosa
Our starting point is the covariant coordinate transformation equation of a relativistic positioning system in Minkowski space–time that maps the receiver’s emission coordinates (proper times broadcast by the emitters) to its coordinates in some inertial reference frame. Bancroft’s analytical (closed-form) solution to the basic pseudorange navigation equations with four emitters is recovered, and the
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Landau Levels versus Hydrogen Atom Universe (IF 2.9) Pub Date : 2024-04-07 Tekin Dereli, Philippe Nounahon, Todor Popov
The Landau problem and harmonic oscillator in the plane share a Hilbert space that carries the structure of Dirac’s remarkable so(2,3) representation. We show that the orthosymplectic algebra osp(1|4) is the spectrum generating algebra for the Landau problem and, hence, for the 2D isotropic harmonic oscillator. The 2D harmonic oscillator is in duality with the 2D quantum Coulomb–Kepler systems, with
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New Timing Results of MSPs from NICER Observations Universe (IF 2.9) Pub Date : 2024-04-07 Shijie Zheng, Dawei Han, Heng Xu, Kejia Lee, Jianping Yuan, Haoxi Wang, Mingyu Ge, Liang Zhang, Yongye Li, Yitao Yin, Xiang Ma, Yong Chen, Shuangnan Zhang
Millisecond pulsars (MSPs) are known for their long-term stability. Using six years of observations from the Neutron Star Interior Composition Explorer (NICER), we have conducted an in-depth analysis of the X-ray timing results for six MSPs: PSRs B1937+21, B1821-24, J0437-4715, J0030+0451, J0218+4232, and J2124-3358. The timing stability parameter σz has been calculated, revealing remarkable timing
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QED Meson Description of the Anomalous Particles at ∼17 and ∼38 MeV Universe (IF 2.9) Pub Date : 2024-04-07 Cheuk-Yin Wong
The Schwinger confinement mechanism stipulates that a massless fermion and a massless antifermion are confined as a massive boson when they interact in the Abelian QED interaction in (1+1)D.If we approximate light quarks as massless and apply the Schwinger confinement mechanism to quarks, we can infer that a light quark and a light antiquark interacting in the Abelian QED interaction are confined as
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Search for Extreme Mass Ratio Inspirals Using Particle Swarm Optimization and Reduced Dimensionality Likelihoods Universe (IF 2.9) Pub Date : 2024-04-06 Xiao-Bo Zou, Soumya D. Mohanty, Hong-Gang Luo, Yu-Xiao Liu
Extreme-mass-ratio inspirals (EMRIs) are significant observational targets for spaceborne gravitational wave detectors, namely, LISA, Taiji, and Tianqin, which involve the inspiral of stellar-mass compact objects into massive black holes (MBHs) with a mass range of approximately 104∼107M⊙. EMRIs are estimated to produce long-lived gravitational wave signals with more than 105 cycles before plunge,
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Quantum Field Theory of Neutrino Mixing in Spacetimes with Torsion Universe (IF 2.9) Pub Date : 2024-04-03 Antonio Capolupo, Giuseppe De Maria, Simone Monda, Aniello Quaranta, Raoul Serao
In the framework of quantum field theory, we analyze the neutrino oscillations in the presence of a torsion background. We consider the Einstein–Cartan theory and we study the cases of constant torsion and of linearly time-dependent torsion. We derive new neutrino oscillation formulae which depend on the spin orientation. Indeed, the energy splitting induced by the torsion influences oscillation amplitudes
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Neutrino at Different Epochs of the Friedmann Universe Universe (IF 2.9) Pub Date : 2024-04-02 Alexandre V. Ivanchik, Oleg A. Kurichin, Vlad Yu. Yurchenko
At least two relics of the Big Bang have survived: the cosmological microwave background (CMB) and the cosmological neutrino background (CνB). Being the second most abundant particle in the universe, the neutrino has a significant impact on its evolution from the Big Bang to the present day. Neutrinos affect the following cosmological processes: the expansion rate of the universe, its chemical and
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The 1932 Majorana Equation: A Forgotten but Surprisingly Modern Particle Theory Universe (IF 2.9) Pub Date : 2024-04-01 Luca Nanni
The Standard Model is an up-to-date theory that best summarizes current knowledge in particle physics. Although some problems still remain open, it represents the leading model which all physicists refer to. One of the pillars which underpin the Standard Model is represented by the Lorentz invariance of the equations that form its backbone. These equations made it possible to predict the existence
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Checking the 8Be Anomaly with a Two-Arm Electron Positron Pair Spectrometer Universe (IF 2.9) Pub Date : 2024-04-01 Tran The Anh, Tran Dinh Trong, Attila J. Krasznahorkay, Attila Krasznahorkay, József Molnár, Zoltán Pintye, Nguyen Ai Viet, Nguyen The Nghia, Do Thi Khanh Linh, Bui Thi Hoa, Le Xuan Chung, Nguyen Tuan Anh
We have repeated the experiment performed recently by ATOMKI Laboratory (Debrecen, Hungary), which may indicate a new particle called X17 in the literature. In order to obtain a reliable and independent result, we used a different structure of the electron–positron pair spectrometer at the VNU University of Science. The spectrometer has two arms and simpler acceptance and efficiency as a function of
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Elliptical Space with the McVittie Metrics Universe (IF 2.9) Pub Date : 2024-03-31 Vladimir N. Yershov
The main feature of elliptical space—the topological identification of its antipodal points—could be fundamental for understanding the nature of the cosmological redshift. The physical interpretation of the mathematical (topological) structure of elliptical space is made by using physical connections in the form of Einstein-Rosen bridges (also called “wormholes”). The Schwarzschild metric of these
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Primordial Black Holes from Spatially Varying Cosmological Constant Induced by Field Fluctuations in Extra Dimensions Universe (IF 2.9) Pub Date : 2024-03-31 Arkady A. Popov, Sergey G. Rubin, Alexander S. Sakharov
The origin and evolution of supermassive black holes (SMBHs) in our universe have sparked controversy. In this study, we explore the hypothesis that some of these black holes may have seeded from the direct collapse of dark energy domains with density significantly higher than the surrounding regions. The mechanism of the origin of such domains relies on the inflationary evolution of a scalar field
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Jets Studies in Central and Forward Regions at Current and Expected Large Hadron Collider Future Energies Universe (IF 2.9) Pub Date : 2024-03-25 M. A. Mahmoud, Somaia Hamdi, A. Radi, M. A. El-Borie, E. A. Tayel
The present work presents a study of jet production in the central region (|η| < 2.5) and the forward region (3 < |η| < 5) in proton–proton collisions at different energies: s = 13.6 TeV, s = 20 TeV, and s = 27 TeV. These energies are the present and expected future energies of the Large Hadron Collider. In addition, the measurement of dijets—where the dijet selected is the one leading the jet in the
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Measuring the Lense–Thirring Precession and the Neutron Star Moment of Inertia with Pulsars Universe (IF 2.9) Pub Date : 2024-03-28 Huanchen Hu, Paulo C. C. Freire
Neutron stars (NSs) are compact objects that host the densest forms of matter in the observable universe, providing unique opportunities to study the behaviour of matter at extreme densities. While precision measurements of NS masses through pulsar timing have imposed effective constraints on the equation of state (EoS) of dense matter, accurately determining the radius or moment of inertia (MoI) of
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A Very-High-Energy Gamma-Ray View of the Transient Sky Universe (IF 2.9) Pub Date : 2024-03-29 Alessandro Carosi, Alicia López-Oramas
The development of the latest generation of Imaging Atmospheric Cherenkov Telescopes (IACTs) over recent decades has led to the discovery of new extreme astrophysical phenomena in the very-high-energy (VHE, E > 100 GeV) gamma-ray regime. Time-domain and multi-messenger astronomy are inevitably connected to the physics of transient VHE emitters, which show unexpected (and mostly unpredictable) flaring
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Standard and Non-Standard Aspects of Neutrino Physics Universe (IF 2.9) Pub Date : 2024-03-30 Alessandro Granelli
This review provides a succinct overview of the basic aspects of neutrino physics. The topics covered include neutrinos in the standard model and the three-neutrino mixing scheme; the current status of neutrino oscillation measurements and what remains to be determined; the seesaw mechanisms for neutrino mass generation and the associated phenomenology, including the leptogenesis mechanism to explain
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Tracking Dusty Cloud Crushed by a Hot Flow Universe (IF 2.9) Pub Date : 2024-03-26 Svyatoslav Dedikov, Evgenii Vasiliev
The destructionof clouds by strong shocks and hot winds is the key process responsible for the transporting of metals and dust from the ISM to the ICM/IGM, and establishing the multiphase structure in and around galaxies. In this work, we perform a detailed analysis of this process using two different approaches for tracking the cloud material (gas and dust): the so-called ‘colored’ fluid, and the
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The Power of Relativistic Jets: A Comparative Study Universe (IF 2.9) Pub Date : 2024-03-27 Luigi Foschini, Benedetta Dalla Barba, Merja Tornikoski, Heinz Andernach, Paola Marziani, Alan P. Marscher, Svetlana G. Jorstad, Emilia Järvelä, Sonia Antón, Elena Dalla Bontà
We present the results of a comparison between different methods to estimate the power of relativistic jets from active galactic nuclei (AGN). We selected a sample of 32 objects (21 flat-spectrum radio quasars, 7 BL Lacertae objects, 2 misaligned AGN, and 2 changing-look AGN) from the very large baseline array (VLBA) observations at 43 GHz of the Boston University blazar program. We then calculated
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Asteroseismology of Compact Stars Universe (IF 2.9) Pub Date : 2024-03-27 Hong-Bo Li, Yong Gao, Lijing Shao, Ren-Xin Xu
Compact stars have been perceived as natural laboratories of matter at an extremely high density. The uncertainties of the equation of state (EOS) of matter can be constrained by observing compact stars. In this review, we investigate the EOSs, global structure, and elastic properties of compact stars. We focus in detail on how to constrain the above properties of compact stars via asteroseismology
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A Needle in a Cosmic Haystack: A Review of FRB Search Techniques Universe (IF 2.9) Pub Date : 2024-03-28 Kaustubh M. Rajwade, Joeri van Leeuwen
Ephemeral Fast Radio Bursts (FRBs) must be powered by some of the most energetic processes in the Universe. That makes them highly interesting in their own right, and as precise probes for estimating cosmological parameters. This field thus poses a unique challenge: FRBs must be detected promptly and immediately localised and studied based only on that single millisecond-duration flash. The problem
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Boyer–Lindquist Space-Times and Beyond: Metamaterial Analogues for ArbitrarySpace-Times Universe (IF 2.9) Pub Date : 2024-03-28 Sebastian Schuster, Matt Visser
Analogue space-times (and in particular metamaterial analogue space-times) have a long varied and rather complex history. Much of the previous related work to this field has focused on spherically symmetric models; however, axial symmetry is much more relevant for mimicking astrophysically interesting systems that are typically subject to rotation. Now it is well known that physically reasonable stationary
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Femtoscopy for the NAno-Plasmoni Laser Inertial Fusion Experiments (NAPLIFE) Project Universe (IF 2.9) Pub Date : 2024-03-29 L. P. Csernai, T. Csörgő, I. Papp, K. Tamosiunas, M. Csete, A. Szenes, D. Vass, T. S. Biró, N. Kroó
Hanbury-Brown and Twiss analysis is used to determine the size and timespan of emitted particles. Here, we propose to adapt this method for laser-induced nanoplasmonic inertial confinement fusion to determine the parameters of emitted Deuterium and Helium4 nuclei. This communication is a short article that presents part of a larger study over multiple years. It presents a cutting edge method that is
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Dynamical Analysis of the Redshift Drift in FLRW Universes Universe (IF 2.9) Pub Date : 2024-03-29 Francisco S. N. Lobo, José Pedro Mimoso, Jessica Santiago, Matt Visser
Redshift drift is the phenomenon whereby the observed redshift between an emitter and observer comoving with the Hubble flow in an expanding FLRW universe will slowly evolve—on a timescale comparable to the Hubble time. In a previous article, three of the current authors performed a cosmographic analysis of the redshift drift in an FLRW universe, temporarily putting aside the issue of dynamics (the
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Scientific Highlights of the AGILE Gamma-ray Mission Universe (IF 2.9) Pub Date : 2024-03-25 Stefano Vercellone, Carlotta Pittori, Marco Tavani
The γ-ray sky above a few tens of megaelectronvolts (MeV) reveals some of the most powerful and energetic phenomena of our Universe. The Astrorivelatore Gamma ad Immagini LEggero (AGILE) Gamma-ray Mission was launched in 2007 with the aim of observing celestial sources by means of three instruments covering a wide range of energies, from hard X-rays up to 30 GeV. Thanks to its wide field of view, AGILE
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The Shock Cone Instabilities and Quasi-Periodic Oscillations around the Hartle–Thorne Black Hole Universe (IF 2.9) Pub Date : 2024-03-24 Orhan Donmez, Fatih Dogan
To explain the observed X-ray data in a black hole–accreting matter system and understand the physical mechanisms behind QPOs, we have numerically modeled the dynamical and oscillation properties of the shock cone formed around both slowly and rapidly rotating Hartle–Thorne black holes, resulting from the mechanism of Bondi–Hoyle–Lyttleton (BHL). According to the numerical simulations, an increase
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Emergent Spacetime and Cosmic Inflation Universe (IF 2.9) Pub Date : 2024-03-21 Hyun Seok Yang
We present a novel background-independent framework for cosmic inflation, starting with a matrix model. In this framework, inflation is portrayed as a dynamic process responsible for the generation of both space and time. This stands in contrast to conventional inflation, which is characterized as a mere (exponential) expansion of an already existing spacetime, driven by the vacuum energy associated
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The κ-Model under the Test of the SPARC Database Universe (IF 2.9) Pub Date : 2024-03-21 Gianni Pascoli
Our main goal here is to conduct a comparative analysis between the well-known MOND theory and a more recent model called the κ-model. An additional connection, between the κ-model and two other novel MOND-type theories, Newtonian Fractional-Dimension Gravity (NFDG) and Refracted Gravity (RG), is likewise presented. All these models are built to overtake the DM paradigm, or at least to strongly reduce
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High-Energy and Ultra-High-Energy Neutrino Astrophysics Universe (IF 2.9) Pub Date : 2024-03-20 Damiano F. G. Fiorillo
The origin of high-energy cosmic rays, and their behavior in astrophysical sources, remains an open question. Recently, new ways to address this question have been made possible by the observation of a new astrophysical messenger, namely neutrinos. The IceCube telescope has detected a diffuse flux of astrophysical neutrinos in the TeV-PeV energy range, likely produced in astrophysical sources accelerating
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The Physics of Core-Collapse Supernovae: Explosion Mechanism and Explosive Nucleosynthesis Universe (IF 2.9) Pub Date : 2024-03-19 Luca Boccioli, Lorenzo Roberti
Recent developments in multi-dimensional simulations of core-collapse supernovae have considerably improved our understanding of this complex phenomenon. In addition to that, one-dimensional (1D) studies have been employed to study the explosion mechanism and its causal connection to the pre-collapse structure of the star, as well as to explore the vast parameter space of supernovae. Nonetheless, many
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Regular Friedmann Universes and Matter Transformations Universe (IF 2.9) Pub Date : 2024-03-13 Alexander Kamenshchik, Polina Petriakova
We apply a very simple procedure to construct non-singular cosmological models for flat Friedmann universes filled with minimally coupled scalar fields or by tachyon Born–Infeld-type fields. Remarkably, for the minimally coupled scalar field and the tachyon field, the regularity of the cosmological evolution, or in other words, the existence of bounce, implies the necessity of the transition between
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Conformally Invariant Gravity and Gravitating Mirages Universe (IF 2.9) Pub Date : 2024-03-17 Victor Berezin, Inna Ivanova
The action of an ideal fluid in Euler variables with a variable number of particles is used for the phenomenological description of the processes of particle creation in strong external fields. It has been demonstrated that the conformal invariance of the creation law imposes quite strict restrictions on the possible types of sources. It is shown that combinations with the particle number density in
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Multiple SSO Space Debris Flyby Trajectory Design Based on Cislunar Orbit Universe (IF 2.9) Pub Date : 2024-03-16 Siyang Zhang, Shuquan Wang
This paper investigates the trajectory design problem in the scenario of a multiple Sun-synchronous Orbit (SSO) space debris flyby mission from a DRO space station. At first, the characteristics of non-planar transfer from DRO to SSO in the Earth–Moon system are analyzed. The methods of large-scale ergodicity and pruning are utilized to investigate single-impulse and two-impulse DRO–Earth transfers
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The ASTRI Mini-Array: A New Pathfinder for Imaging Cherenkov Telescope Arrays Universe (IF 2.9) Pub Date : 2024-03-16 Salvatore Scuderi
The ASTRI Mini-Array is an Istituto Nazionale di Astrofisica (INAF) project to build and operate an array of nine Imaging Atmospheric Cherenkov Telescopes (IACTs) at the Teide Astronomical Observatory of the Instituto de Astrofisica de Canarias in Tenerife (Spain) based on a host agreement with INAF and, as such, it will be the largest IACT array until the Cherenkov Telescope Array Observatory starts
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On the Apparent Discretization of Spacetime and Its Connection with the Cosmological Constant Universe (IF 2.9) Pub Date : 2024-03-14 Jaume Giné, Giuseppe Gaetano Luciano
The emergence of a minimal observable length of order of the Planck scale is a prediction of many quantum theories of gravity. However, the question arises as to whether this is a real fundamental length affecting nature in all of its facets, including spacetime. In this work, we show that the quantum measurement process implies the existence of a minimal measurable length and consequently the apparent
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Origins and Natures of Inflation, Dark Matter and Dark Energy Universe (IF 2.9) Pub Date : 2024-03-15 Kazuharu Bamba
Various precise cosmological observations, e [...]
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The Quantum Hall Effect under the Influence of Gravity and Inertia: A Unified Approach Universe (IF 2.9) Pub Date : 2024-03-13 Alexandre Landry, Fayçal Hammad, Reza Saadati
The quantum Hall effect under the influence of gravity and inertia is studied in a unified way. We make use of an algebraic approach, as opposed to an analytic approach. We examine how both the integer and the fractional quantum Hall effects behave under a combined influence of gravity and inertia using a unified Hamiltonian. For that purpose, we first re-derive, using the purely algebraic method,
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The Relevance of Dynamical Friction for the MW/LMC/SMC Triple System Universe (IF 2.9) Pub Date : 2024-03-14 Wolfgang Oehm, Pavel Kroupa
Simulations of structure formation in the standard cold dark matter cosmological model quantify the dark matter halos of galaxies. Taking into account dynamical friction between dark matter halos, we investigate the past orbital dynamical evolution of the Magellanic Clouds in the presence of the Galaxy. Our calculations are based on a three-body model of rigid Navarro–Frenk–White profiles for dark
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Classification of Planetary Motion around Super-Jupiters and Brown Dwarfs Universe (IF 2.9) Pub Date : 2024-03-13 Euaggelos E. Zotos, Eman M. Moneer, Tobias C. Hinse
We investigate the orbital dynamics of an exosystem consisting of a solar-mass host star, a transiting body, and an Earth-size exoplanet within the framework of the generalized three-body problem. Depending on its mass, the transiting body can either be a super-Jupiter or a brown dwarf. To determine the final states of the Earth-size exoplanet, we conduct a systematic and detailed classification of
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Nuclear Modification Factor of Inclusive Charged Particles in Au+Au Collisions at sNN = 27 GeV with the STAR Experiment Universe (IF 2.9) Pub Date : 2024-03-13 Alisher Aitbayev
The Beam Energy Scan (BES) program at RHIC aims to explore the QCD phase diagram, including the search for the evidence of the 1st order phase transition from hadronic matter to Quark-Gluon Plasma (QGP) and the location of the QCD critical point. One of the features previously observed in the study of QGP is the effect of suppression of particle production with high transverse momenta pT (>2 GeV/c)
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A Critical Discussion on the H0 Tension Universe (IF 2.9) Pub Date : 2024-03-13 Salvatore Capozziello, Giuseppe Sarracino, Giulia De Somma
A critical discussion on the H0 Hubble constant tension is presented by considering both early and late-type observations. From recent precise measurements, discrepancies emerge when comparing results for some cosmological quantities obtained at different redshifts. We highlight the most relevant measurements of H0 and propose potential ideas to solve its tension. These solutions concern the exploration
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Constraining the Initial Mass Function in the Epoch of Reionization from Astrophysical and Cosmological Data Universe (IF 2.9) Pub Date : 2024-03-13 Andrea Lapi, Giovanni Gandolfi, Lumen Boco, Francesco Gabrielli, Marcella Massardi, Balakrishna S. Haridasu, Carlo Baccigalupi, Alessandro Bressan, Luigi Danese
We aim to constrain the stellar initial mass function (IMF) during the epoch of reionization. To this purpose, we build up a semi-empirical model for the reionization history of the Universe based on various ingredients: the latest determination of the UV galaxy luminosity function from JWST out to redshift z≲12; data-inferred and simulation-driven assumptions on the redshift-dependent escape fraction
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Isovector Axial Charge and Form Factors of Nucleons from Lattice QCD Universe (IF 2.9) Pub Date : 2024-03-12 Rajan Gupta
A survey of the calculations of the isovector axial vector form factor of the nucleon using lattice QCD is presented. Attention is paid to statistical and systematic uncertainties, in particular those due to excited state contributions. Based on a comparison of results from various collaborations, a case is made that lattice results are consistent within 10%. A similar level of uncertainty is in the
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Weak Coupling Regime in Dilatonic f(R,T) Cosmology Universe (IF 2.9) Pub Date : 2024-03-11 Francisco A. Brito, Carlos H. A. B. Borges, José A. V. Campos, Francisco G. Costa
We consider f(R,T) modified theories of gravity in the context of string-theory-inspired dilaton gravity. We deal with a specific model that under certain conditions describes the late time Universe in accord with observational data in modern cosmology and addresses the H0 tension. This is done by exploring the space of parameters made out of those coming from the modified gravity and dilatonic charge
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Analysis of the Geodesic Motions of Massive Particles in Kerr–Sen–AdS4 Spacetime Universe (IF 2.9) Pub Date : 2024-03-08 Ziqiang Cai, Ming Liu, Wen-Qian Wang, Tong-Yu He, Zhan-Wen Han, Rong-Jia Yang
We consider geodesic motions in Kerr–Sen–AdS4 spacetime. We obtain equations of motion for light rays and test particles. Using parametric diagrams, we show some regions where radial and latitudinal geodesic motions are allowed. We analyze the impact of parameters related to the dilatonic scalar on the orbit and find that it will result in more rich and complex orbital types.
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A Simple Direct Empirical Observation of Systematic Bias of the Redshift as a Distance Indicator Universe (IF 2.9) Pub Date : 2024-03-06 Lior Shamir
Recent puzzling observations, such as the H0 tension, large-scale anisotropies, and massive disk galaxies at high redshifts, have been challenging the standard cosmological model. While one possible explanation is that the standard model is incomplete, other theories are based on the contention that the redshift model as a distance indicator might be biased. These theories can explain the recent observations
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The Modeling of Pulsar Magnetosphere and Radiation Universe (IF 2.9) Pub Date : 2024-03-07 Gang Cao, Xiongbang Yang, Li Zhang
We review the recent advances in the pulsar high-energy γ-ray observation and the electrodynamics of the pulsar magnetospheres from the early vacuum model to the recent plasma-filled models by numerical simulations. The numerical simulations have made significant progress toward the self-consistent modeling of the plasma-filled magnetosphere by including the particle acceleration and radiation. The
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Transport Coefficients of Relativistic Matter: A Detailed Formalism with a Gross Knowledge of Their Magnitude Universe (IF 2.9) Pub Date : 2024-03-07 Ashutosh Dwibedi, Nandita Padhan, Arghya Chatterjee, Sabyasachi Ghosh
The present review article has attempted a compact formalism description of transport coefficient calculations for relativistic fluid, which is expected in heavy ion collision experiments. Here, we first address the macroscopic description of relativistic fluid dynamics and then its microscopic description based on the kinetic theory framework. We also address different relaxation time approximation-based
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Correction: Cuello, N.; Sucerquia, M. Alpha Centauri: Disc Dynamics, Planet Stability, Detectability. Universe 2024, 10, 64 Universe (IF 2.9) Pub Date : 2024-03-04 Nicolás Cuello, Mario Sucerquia
In the original publication [...]
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Assessing the Similarity of Continuous Gravitational-Wave Signals to Narrow Instrumental Artifacts Universe (IF 2.9) Pub Date : 2024-03-04 Rafel Jaume, Rodrigo Tenorio, Alicia M. Sintes
Continuous gravitational-wave (CW) signals are long-lasting quasi-monochromatic gravitational-wave signals expected to be emitted by rapidly rotating non-axisymmetric neutron stars. Depending on the rotational frequency and sky location of the source, certain CW signals may behave in a similar manner to narrow-band artifacts present in ground-based interferometric detectors. Part of the detector characterization
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Theoretically Motivated Dark Electromagnetism as the Origin of Relativistic Modified Newtonian Dynamics Universe (IF 2.9) Pub Date : 2024-03-04 Felix Finster, José M. Isidro, Claudio F. Paganini, Tejinder P. Singh
The present paper is a modest attempt to initiate the research program outlined in this abstract. We propose that general relativity and relativistic MOND (RelMOND) are analogues of broken electroweak symmetry. That is, SU(2)R×U(1)YDEM→U(1)DEM (DEM stands for dark electromagnetism), and GR is assumed to arise from the broken SU(2)R symmetry and is analogous to the weak force. RelMOND is identified
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Simple Lévy α-Stable Model Analysis of Elastic pp and pp¯ Low-|t| Data from SPS to LHC Energies Universe (IF 2.9) Pub Date : 2024-03-06 Tamás Csörgő, Sándor Hegyi, István Szanyi
A simple Lévy α-stable (SL) model is used to describe the data on elastic pp and pp¯ scattering at low-|t| from SPS energies up to LHC energies. The SL model is demonstrated to describe the data with a strong non-exponential feature in a statistically acceptable manner. The energy dependence of the parameters of the model is determined and analyzed. The Lévy α parameter of the model has an energy-independent
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On Phase Transitions during Collisions near the Horizon of Black Holes Universe (IF 2.9) Pub Date : 2024-03-07 Andrey A. Grib, Yuri V. Pavlov
During particle collisions in the vicinity of the horizon of black holes, it is possible to achieve energies and temperatures corresponding to phase transitions in particle physics. It is shown that the sizes of the regions of the new phase are of the order of the Compton length for the corresponding mass scale. The lifetime is also on the order of the Compton time. It is shown that the inverse influence