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# Astrophysics - Science topic

Astrophysics is the branch of astronomy that deals with the physics of the universe, including the physical properties of celestial objects, as well as their interactions and behavior.
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Publications related to Astrophysics (10,000)
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The IceCube Neutrino Observatory is a cubic kilometer neutrino detector located at the geographic South Pole designed to detect high-energy astrophysical neutrinos. To thoroughly understand the detected neutrinos and their properties, the detector response to signal and background has to be modeled using Monte Carlo techniques. An integral part of...
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In this paper, ACol database for the collisional processes in atom and Rydberg atom collisions is described. Database (DB) is hosted and is a part of the Serbian Virtual Observatory (SerVO) and VAMDC project. The database contains the rate coefficients for excitation and ionization collisional processes in hydrogen, helium and alkali plasmas. The A...
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A lot of numerical formulations of physical phenomena contain 9th-order BVPs. The presented probe intends to consider the spline solutions of the 9th-order boundary value problems using Cubic B Spline(CBS). Ninth order boundary value problems arise in the study of laminar viscous flow in a semi-porous channel, astrophysics, hydrodynamic & hydro-mag...
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The next two decades are expected to open the door to the first coincident detections of electromagnetic (EM) and gravitational-wave (GW) signatures associated with massive black-hole (MBH) binaries heading for coalescence. These detections will launch a new era of multimessenger astrophysics by expanding this growing field to the low-frequency GW...
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The unidentified infrared (UIR) bands, whose carriers are thought to be organics, have been widely observed in various astrophysical environments. However, our knowledge of the detailed chemical composition and formation process of the carriers is still limited. We have synthesized laboratory organics named Quenched Nitrogen-included Carbonaceous C...
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Thanks to the long-term collaborations between nuclear and astrophysics, we have good understanding on the origin of elements in the universe, except for the elements around Ti and some neutron-capture elements. From the comparison between observations of nearby stars and Galactic chemical evolution models, a rapid neutron-capture process associate...
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In some extensions of the Standard Model (SM), two neutrons are allowed to decay into a pair of sterile anti-neutrinos ($nn \rightarrow \bar{\chi}\bar{\chi}$) via new scalar bosons. This process violates both the baryon number ($\mathcal{B}$) and the lepton number ($\mathcal{L}$) by two units but conserves their difference (\mathcal{B}-\mathcal{L}... Article Full-text available Artificial neural networks are gaining a momentum for solving complex problems in all sorts of data analysis and classification matters. As such, idea of determining their usability on complex plasma came up. The choice for the input data for the analysis is a set of stellar spectral data. It consists of complex composition plasma under vast variet... Article Full-text available Astrophysical sources of neutrinos detected by large-scale neutrino telescopes remain uncertain. While there exist statistically significant observational indications that a part of the neutrino flux is produced by blazars, numerous theoretical studies suggest also the presence of potential Galactic point sources. Some of them have been observed in... Article Full-text available Recent astrophysical transient Swift J1913.1+1946 is possibly associated with the gamma-ray burst GRB 221009A at the redshift z ≈ 0.151. The transient was accompanied by very high-energy gamma rays up to 18 TeV observed by LHAASO and a photon-like air shower of 251 TeV detected by Carpet-2. These energetic gamma rays cannot reach us from the claime... Article Full-text available The existence of the million-degree corona above the cooler photosphere is an unsolved problem in astrophysics. Detailed study of the quiescent corona that exists regardless of the phase of the solar cycle may provide fruitful hints toward resolving this conundrum. However, the properties of heating mechanisms can be obtained only statistically in... Article Full-text available The core of this manuscript is to conduct a broad investigation into the features of static matter configurations with hyperbolical symmetry, which might possibly serve as formation of corresponding spacetime within the limits of f(R,T,Q) gravity, where (Q ≡ RασTασ). We recognize that such matter distributions can be anisotropic in pressure, with j... Article Full-text available We generalize a recently proposed confining relativistic density-functional approach to the case of density-dependent vector and diquark couplings. The particular behavior of these couplings is motivated by the non-perturbative gluon exchange in dense quark matter and provides the conformal limit at asymptotically high densities. We demonstrate tha... Article Full-text available We consider the general class of theories in which there is a new ultralight scalar field that mediates an equivalence principle violating, long-range force. In such a framework, the Sun and Earth act as sources of the scalar field, leading to potentially observable location-dependent effects on atomic and nuclear spectra. We determine the sensitiv... Preprint Full-text available Interactions between photons and electrons are ubiquitous in astrophysics. Photons can be down scattered (Compton scattering) or up scattered (inverse Compton scattering) by moving electrons. Inverse Compton scattering, in particular, is an essential process for the production of astrophysical gamma rays. Computations of inverse Compton emission ty... Article Full-text available Current searches for gravitational waves from compact-binary objects are primarily designed to detect the dominant gravitational-wave mode and assume that the binary components have spins which are aligned with the orbital angular momentum. These choices lead to observational biases in the observed distribution of sources. Sources with significant... Preprint Full-text available In this abstract we explore the possibility of introducing biases in physical parameter inference models from adversarial-type attacks. In particular, we inject small amplitude systematics into inputs to a mixture density networks tasked with inferring cosmological parameters from observed data. The systematics are constructed analogously to white-... Article Full-text available The study of matter under extreme densities and temperatures as they occur, for example, in astrophysical objects and nuclear fusion applications has emerged as one of the most active frontiers in physics, material science, and related disciplines. In this context, a key quantity is given by the dynamic structure factor S ( q , ω ), which is probed... Preprint Full-text available Measurements of the elastic scattering cross section of 3He and 4He are important in order to improve constraints on theoretical models of 4He(3He,g)7Be, a key reaction in Big Bang nucleosynthesis and solar neutrino production. The astrophysical S-factor for this reaction is a significant source of uncertainty in the standard solar-model prediction... Conference Paper Full-text available Dusty plasmas (DPs) are one of the fundamental ingredients of the universe. It is a mixture of plasma particles and dust charges. DP consists of plasma and both dust. Due to the inclusion of dust particles in plasma, the plasma becomes more complex in its behaviors. So, such plasmas are also termed as "complex plasmas." DP plays a very significant... Preprint Full-text available Diverse cosmological and astrophysical observations strongly hint at the presence of dark matter and dark energy in the Universe. One of the main goals of Cosmology is to explain the nature of these two components. It may well be that both dark matter and dark energy have a common origin. In this paper, we develop a model in which the dark sector a... Article Full-text available We calculate the shear ( $$\eta$$ η ) and bulk viscosity ( $$\zeta$$ ζ ) of Self Interacting Dark Matter (SIDM) fluid using the kinetic theory formalism. Using the astrophysical constraints on dark matter self-interaction cross section over mass $$\sigma /m$$ σ / m , we demonstrate that viscous SIDM fluid violates the lower bound on the ratio o... Preprint Full-text available Information Extraction from scientific literature can be challenging due to the highly specialised nature of such text. We describe our entity recognition methods developed as part of the DEAL (Detecting Entities in the Astrophysics Literature) shared task. The aim of the task is to build a system that can identify Named Entities in a dataset compo... Article Full-text available Resolved observations of debris discs can be used to derive radial profiles of Azimuthally-averaged Surface Density (ASD), which carries important information about the disc structure even in the presence of non-axisymmetric features and has improved signal-to-noise characteristics relative to the two-dimensional surface brightness measurements. We... Preprint Full-text available We consider the cosmology and phenomenology of a dark photon portal to a simple dark sector consisting of a single, light, fermionic dark matter particle species with mass in the MeV range. We entertain three possible kinetic mixing structures of a new Abelian gauge group U(1)_{\text{dark}}$with the visible sector through U(1)$_{\text{e.m.}}$, U(... Article Full-text available In compact astrophysical objects, the neutrino density can be so high that neutrino-neutrino refraction can lead to fast flavor conversion of the kind νeν¯e↔νxν¯x with x=μ, τ, depending on the neutrino angle distribution. Previously, we have shown that in a homogeneous, axisymmetric two-flavor system, these collective solutions evolve in analogy to... Preprint Full-text available In this Letter, we investigate jet-launching abilities of Bondi-like accretion flows with zero or low specific angular momentum by performing 3D general relativistic magnetohydrodynamic simulations. In order to check if relativistic jets can be launched magnetically, we thread the accretion flow with large-scale poloidal magnetic field, and choose... Article Full-text available We consider a muonphilic axionlike particle (ALP), denoted as a, lighter than twice the muon mass. ALPs of this mass range dominantly decay into a pair of photons, induced by a triangular muon loop. Such light muonphilic ALPs are naturally long lived. At the atmosphere, the ALPs are copiously produced from charged-meson decays in air showers, such... Preprint Full-text available Extracting the maximum amount of cosmological and astrophysical information from upcoming large-scale surveys remains a challenge. This includes evaluating the exact likelihood, parameter inference and generating new diverse synthetic examples of the incoming high-dimensional data sets. In this work, we propose the use of normalizing flows as a gen... Preprint Full-text available The rate of energy loss and orbital period decay of quasi-stable compact binary systems are derived in$f(R)$theory of gravity using the method of a single vertex graviton emission process from a classical source. After linearising the$f(R)\$ action written in an equivalent scalar-tensor format in the Einstein frame, we identify the appropriate in...
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Life on earth is protected from astrophysical cosmic rays by the heliospheric magnetic and slowly varying geomagnetic fields, and by collisions with oxygen and nitrogen molecules in the atmosphere. The collisions generate showers of particles of lesser energy; only muons, a charged particle with a mass between that of an electron and a proton, can...
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To examine the gas-phase hydrogen/deuterium exchange on large, astronomically relevant cationic polycyclic aromatic hydrocarbons (PAHs), the ion-molecule collision reaction between C 42 H 18 ⁺ (hexa-peri-hexabenzocoronene cations, HBC ⁺ ) and D atoms is studied. The experimental results show that the deuterated HBC cations ([C 42 H m D n ] ⁺ , m +2...
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Since particles obey wave equations, one is not free to postulate that particles move on test particle geodesics. Rather, to derive such behavior from equations of motion one can employ the eikonal approximation. We show that eikonalization does not in general lead to null geodesics for curved space massless rays, and the standard null-geodesic-bas...
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Score-based generative models have emerged as alternatives to generative adversarial networks (GANs) and normalizing flows for tasks involving learning and sampling from complex image distributions. In this work we investigate the ability of these models to generate fields in two astrophysical contexts: dark matter mass density fields from cosmolog...
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This paper concerns solutions to the Hardy–Hénon equation \begin{aligned} -\Delta u = |x|^\sigma u^p \end{aligned} - Δ u = | x | σ u p in $${{\,\mathrm{{\textbf{R}}}\,}}^n$$ R n with $$n \ge 1$$ n ≥ 1 and arbitrary $$p, \sigma \in {{\,\mathrm{{\textbf{R}}}\,}}.$$ p , σ ∈ R . This equation was proposed by Hénon in 1973 as a model to study rotati...
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Dynamos wherein magnetic field is produced from velocity fluctuations are fundamental to our understanding of several astrophysical and/or laboratory phenomena. Though fluid helicity is known to play a key role in the onset of dynamo action, its effect is yet to be fully understood. In this work, a fluid flow proposed recently [Yoshida et al. Phys....
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The theoretical framework of the neutrino electron excitation at low energies including the screening effect in semiconductor detectors is developed for the first time, both in the Standard Model of particle physics and in the presence of the neutrino magnetic moment. We explore the contribution of the screening effect of semiconductors to the neut...
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A photometer is a tool that can be used as a medium for learning, practicum and research to study the quality of the night sky in Astrophysics courses. The photometry practicum provides work principles, tool settings and data collection knowledge. Currently, the Earth and Space Laboratory of the Department of Physics Education has only one photomet...
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TeV-scale dark matter is well motivated by notions of naturalness as the new physics threshold is expected to emerge in the TeV regime. We extend the Standard Model by adding an arbitrary SU(2) dark matter multiplet in non-chiral representation. The pseudo-real representations can be viable DM candidates providing that one includes a higher dimensi...
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A bstract We use Swampland principles to theoretically disfavor regions of the parameter space of dark matter and other darkly charged particles that may exist. The Festina Lente bound, the analogue of the Weak-Gravity conjecture in de Sitter, places constraints on the mass and charge of dark particles, which here we show cover regions in parameter...
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Modern astronomical observations give unprecedented access to the physical properties of nearby galaxies, including spatially resolved stellar populations. However, observations can only give a present-day view of the Universe, whereas cosmological simulations give access to the past record of the processes that galaxies have experienced in their e...
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Artículo presentado al concurso CPAN 2022. Se presenta una visión divulgativa del fondo cósmico de microondas(fotones), neutrinos y de gravitones, así como una especulación sobre otros fondos cósmicos posibles. Se indica su relevancia en Física, Astrofísica y Cosmología desde un punto de vista físico y matemático intuitivo simplificado.
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Magnetorotational instability (MRI) is the most likely mechanism driving angular momentum transport in astrophysical disks. However, despite many efforts, a direct experimental evidence of MRI in laboratory is still missing. Recently, performing 1D linear analysis of the standard version of MRI (SMRI) between two rotating coaxial cylinders with an...
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We study the impact of asymmetric bosonic dark matter on neutron star properties, including possible changes of tidal deformability, maximum mass, radius, and matter distribution inside the star. The conditions at which dark matter particles tend to condensate in the star's core or create an extended halo are presented. We show that dark matter con...
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With the onset of large-scale astronomical surveys capturing millions of images, there is an increasing need to develop fast and accurate deconvolution algorithms that generalize well to different images. A powerful and accessible deconvolution method would allow for the reconstruction of a cleaner estimation of the sky. The deconvolved images woul...
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Extreme-mass-ratio inspirals (EMRIs) are promising target sources for space-based interferometers such as LISA, Taiji, and Tianqin. Depending on the astrophysical environment, such as close perturbers or an accretion disk, EMRI orbital evolution may deviate from the predictions of general relativity in vacuum. In particular, we focus on the resonan...
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A bstract We address the question whether a violation of Lorentz symmetry can explain the tension between the measurement and the Standard-Model prediction of the anomalous magnetic moment of the muon, ( g − 2) μ , and whether it can significantly impact the one of the electron, ( g — 2) e . While anisotropic Lorentz-violating effects are, in gener...
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We consider multicomponent dark matter in a model where one dark matter component is feebly interacting (FIMP) while the second is weakly interacting (WIMP). The model contains an inert scalar doublet and a complex scalar singlet and features a discrete Z4 symmetry. Using new features of micromegas that allow us to compute the relic density for mul...
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Gravitational waves from ~90 black hole binary systems have been detected and their progenitors' properties inferred1 so far by the Laser Interferometer Gravitational-Wave Observatory2 and Virgo3 experiments. This has allowed the scientific community to draw conclusions on the formation channels of black holes in binaries, informing population mode...
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Contemporary ultraintense, short-pulse laser systems provide extremely compact setups for the production of high-flux neutron beams, such as those required for nondestructive probing of dense matter, research on neutron-induced damage in fusion devices or laboratory astrophysics studies. Here, by coupling particle-in-cell and Monte Carlo numerical...
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Information from gravitational wave detectors can be used to inform our understanding of the astrophysical populations of black holes in the universe, as well as our understanding of their formation. Detections from binaries composed of black holes which lie outside the bulk of the distribution of the astrophysical population are of particular inte...
Preprint
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With the onset of large-scale astronomical surveys capturing millions of images, there is an increasing need to develop fast and accurate deconvolution algorithms that generalize well to different images. A powerful and accessible deconvolution method would allow for the reconstruction of a cleaner estimation of the sky. The deconvolved images woul...
Preprint
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We describe the sources of stray light and thermal background that affect JWST observations; report actual backgrounds as measured from commissioning and early science observations; compare those background levels to pre-launch predictions; estimate the impact of the backgrounds on science performance; and explore how the backgrounds probe the achi...
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Several anomalous electromagnetic effects that can take place in quark matter at low temperatures and intermediate densities will be discussed. The anomalous transport properties of the spatially inhomogeneous phase of quark matter known as the Magnetic Dual Chiral Density Wave (MDCDW) phase will be reviewed. Going beyond mean-field approximation,...
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Active Galactic Nuclei (AGNs) and their relativistic jets belong to the most promising class of ultra-high-energy cosmic ray (UHECR) accelerators. This compact review summarises basic experimental findings by recent instruments, and discusses possible interpretations and astrophysical constraints on source energetics. Particular attention is given...
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As an emerging approach to space situational awareness and space imaging, the practical use of an event-based camera in space imaging for precise source analysis is still in its infancy. The nature of event-based space imaging and data collection needs to be further explored to develop more effective event-based space image systems and advance the...
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We consider the light emitters moving freely along the geodesics on the equatorial plane near a Kerr black hole and study the observability of these emitters. To do so, we assume these emitters emit the photons isotropically and monochromatically, and we compute the photon escaping probability (PEP) and the maximum observable blueshift (MOB) of the...
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Imaging Atmospheric Cherenkov Telescopes (IACT) of TAIGA astrophysical complex allow to observe high energy gamma radiation helping to study many astrophysical objects and processes. TAIGA-IACT enables us to select gamma quanta from the total cosmic radiation flux and recover their primary parameters, such as energy and direction of arrival. The tr...
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We present a new method which leverages conditional Generative Adversarial Networks (cGAN) to reconstruct galaxy cluster convergence from lensed CMB temperature maps. Our model is constructed to emphasize structure and high-frequency correctness relative to the Residual U-Net approach presented by Caldeira, et. al. (2019). Ultimately, we demonstrat...
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The influence of thermal effects on neutrino–nucleus reactions occurring under supernova conditions is studied. The approach used is based on the quasiparticle random phase approximation extended to finite temperatures using the superoperator formalism. Using the example of the 56Fe and 82Ge nuclei, a detailed analysis of the influence of thermal...
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Multiband observations of coalescing stellar-mass black holes binaries could deliver valuable information on the formation of such sources and potential deviations from general relativity. Some of these binaries might be first detected by the space-based detector LISA and, then, several years later, observed with ground-based detectors. Due to larg...
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The explosion of scientific publications overloads researchers with information. This is even more dramatic for interdisciplinary studies, where several fields need to be explored. A tool to help researchers overcome this is Natural Language Processing (NLP): a machine-learning (ML) technique that allows scientists to automatically synthesize infor...
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A unique challenge for data analysis with the Laser Interferometer Space Antenna (LISA) is that the noise backgrounds from instrumental noise and astrophysical sources will change significantly over both the year and the entire mission. Variations in the noise levels will be on timescales comparable to, or shorter than, the time most signals spend...
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Nuclear astrophysics is a field at the intersection of nuclear physics and astrophysics, which seeks to understand the nuclear engines of astronomical objects and the origin of the chemical elements. This white paper summarizes progress and status of the field, the new open questions that have emerged, and the tremendous scientific opportunities th...
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