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We study the dark energy equation of state as a function of redshift in a non-parametric way, without imposing any {\it a priori} $w(z)$ (ratio of pressure over energy density) functional form. As a check of the method, we test our scheme…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-05 Sergey Postnikov , Maria Giovanna Dainotti , Xavier Hernandez , Salvatore Capozziello

Context. The increased detection rate of Fast Radio Bursts (FRBs) makes it likely to get samples of sizes $\mathcal{O}(10^2)$ to $\mathcal{O}(10^3)$ in the near future. Because of their extragalactic origin can help us in understanding the…

High Energy Astrophysical Phenomena · Physics 2021-05-28 Albert Wai Kit Lau , Ayan Mitra , Mehdi Shafiee , George Smoot

We test the Etherington cosmic distance-duality relation (CDDR), by comparing Type Ia supernova (SNIa) luminosity-distance information from the Pantheon+ compilation with an angular-diameter-distance reconstructed from localized Fast Radio…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-20 Jéferson A. S. Fortunato , Surajit Kalita , Amanda Weltman

A definitive determination of the progenitors of type Ia supernovae (SNIa) has been a conundrum for decades. The single degenerate scenario $-$ a white dwarf (WD) in a semi-detached binary system accreting mass from its secondary $-$ is a…

Solar and Stellar Astrophysics · Physics 2015-06-23 Yael Hillman , Dina Prialnik , Attay Kovetz , Michael M. Shara

The local (v<1200kms) and the cosmic expansion field out to 30000kms-1 are characterized by Ho=58. While the random error is small (+-2), it may still be affected by systematic errors as large as 10%. The local expansion is outlined by…

Astrophysics · Physics 2009-11-07 G. A. Tammann , B. Reindl

Fast Radio Bursts have recently been used to place limits on Einstein's Equivalence Principle via observations of time delays between photons of different radio frequencies by \citet{wei15}. These limits on differential post-Newtonian…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-06 Steven J Tingay , David L Kaplan

We present a fully computable a posteriori error estimator for piecewise linear finite element approximations of reaction-diffusion problems with mixed boundary conditions and piecewise constant reaction coefficient formulated in arbitrary…

Numerical Analysis · Mathematics 2015-07-06 Mark Ainsworth , Tomáš Vejchodský

The experimental determination of the cross-section of the ^{12}C+^{12}C reaction has never been made at astrophysically relevant energies (E<2 MeV). The profusion of resonances throughout the measured energy range has led to speculation…

Solar and Stellar Astrophysics · Physics 2011-11-23 E. Bravo , L. Piersanti , I. Domínguez , O. Straniero , J. Isern , J. A. Escartín

We compare multi-wavelength SFR indicators out to z~3 in GOODS-South. Our analysis uniquely combines U-to-8um photometry from FIREWORKS, MIPS 24um and PACS 70, 100, and 160um photometry from the PEP survey, and Ha spectroscopy from the SINS…

We investigate the future evolution of the universe using the Buchert framework for averaged backreaction in the context of a two-domain partition of the universe. We show that this approach allows for the possibility of the global…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Amna Ali , A. S. Majumdar

We re-examine the contentious question of constraints on anisotropic expansion from Type Ia supernovae (SNIa) in the light of a novel determination of peculiar velocities, which are crucial to test isotropy with supernovae out to distances…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-08 W. Rahman , R. Trotta , S. S. Boruah , M. J. Hudson , D. A. van Dyk

We spatially and temporally resolve the future Supernova (SN) rate in the Solar vicinity and the whole Galaxy by comparing observational parameters of massive stars with theoretical models for estimating age and mass and, hence, the…

Solar and Stellar Astrophysics · Physics 2014-11-18 J. G. Schmidt , M. M. Hohle , R. Neuhäuser

Two ROSAT high resolution images separated by nearly five years have been used to determine the expansion of the X-ray remnant of Tycho's supernova (SN1572). The current expansion rate averaged over the entire remnant is $0.124\pm0.011$ %…

Astrophysics · Physics 2009-10-31 John P. Hughes

We present a star formation rate function (SFRF) at $z\sim6$ based on star formation rates (SFRs) derived by spectral energy distribution (SED) fitting on data from rest-frame UV to optical wavelength of galaxies in the CANDELS GOODS-South…

Astrophysics of Galaxies · Physics 2023-11-21 Yoshihisa Asada , Kouji Ohta

We study the spectro-temporal characteristics of two repeating fast radio bursts (FRBs), namely, FRB 20180916B and FRB 20180814A, and combine the results with those from our earlier analysis on FRB 20121102A. The relationship between the…

High Energy Astrophysical Phenomena · Physics 2021-08-25 Mohammed A. Chamma , Fereshteh Rajabi , Christopher M. Wyenberg , Abhilash Mathews , Martin Houde

We present a new model-independent strategy for testing the Friedmann-Lema\^{\i}tre-Robertson-Walker metric and constraining cosmic curvature, based on future time delay measurements of strongly lensed quasar-elliptical galaxy systems from…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-20 Kai Liao , Zhengxiang Li , Guo-Jian Wang , Xi-Long Fan

We investigate constraints on large extra dimensions (LED) using the latest results from reactor antineutrino experiments. Specifically, we analyze the full data sets from Daya Bay, RENO, KamLAND, NEOS, and STEREO to derive updated bounds.…

High Energy Physics - Phenomenology · Physics 2025-10-16 T. Gökalp Elaçmaz , Ivan Martinez-Soler , Yuber F. Perez-Gonzalez

We consider an effective viscous pressure as the result of a backreaction of inhomogeneities within Buchert's formalism. The use of an effective metric with a time-dependent curvature radius allows us to calculate the luminosity distance of…

General Relativity and Quantum Cosmology · Physics 2016-04-13 Rodrigo M. Barbosa , G. Eddy , I. Chirinos , Winfried Zimdahl , Oliver F. Piattella

We have derived new bounds on the relativistic energy density in the Universe from cosmic microwave background (CMB), large scale structure (LSS), and type Ia supernova (SNI-a) observations. In terms of the effective number of neutrino…

Astrophysics · Physics 2009-11-13 Steen Hannestad

We simulate time-dependent particle acceleration in the blast wave of a young supernova remnant (SNR), using a Monte Carlo approach for the diffusion and acceleration of the particles, coupled to an MHD code. We calculate the distribution…

High Energy Astrophysical Phenomena · Physics 2015-05-18 K. M. Schure , A. Achterberg , R. Keppens , Jacco Vink
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