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Related papers: Galactic hum

200 papers

We discuss the radio spectrum of Sgr A* \index{Sgr A*, radio spectrum} in the frequency range between $\approx 1\,{\rm GHz}$ and $\approx 1\,000\,{\rm GHz}$, show that it can be explained by optically thin synchrotron radiation \index{Sgr…

Astrophysics · Physics 2007-05-23 Wolfgang J. Duschl , Harald Lesch

One of the greatest challenges facing gravitational wave astronomy in the low frequency band is the confusion noise generated by the vast numbers of unresolved galactic and extra galactic binary systems. Estimates of the binary confusion…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Neil J. Cornish

Motivated by the various examples of spatial variability in the power of the acoustic spectrum, we attempted to look for spatial variability in the peak frequency of the spectrum. However, the determination of this peak frequency on a…

Astrophysics · Physics 2015-06-24 P. Venkatakrishnan , Brajesh Kumar , S. C. Tripathy

Models of string cosmology predict a stochastic background of gravitational waves with a spectrum that is strongly tilted towards high frequencies. I give simple approximate expressions for spectral densities of the cosmic background which…

High Energy Physics - Theory · Physics 2008-02-03 Ram Brustein

Gravitational-wave detections have revealed a previously unknown population of stellar mass black holes with masses above $20\, M_{\odot}$. These observations provide a new way to test models of stellar evolution for massive stars. By…

High Energy Astrophysical Phenomena · Physics 2018-04-25 Colm Talbot , Eric Thrane

The spectra of the relic gravitons are customarily normalized in the low-frequency domain where the signal of the concordance paradigm is expected to peak and this is why their contribution to the temperature and polarization anisotropies…

General Relativity and Quantum Cosmology · Physics 2022-08-17 Massimo Giovannini

We consider the vibrations and waves in the atmosphere under the gravitation on the flat earth. The stratified density distribution of the back ground equilibrium is supposed to touch the vacuum at the finite height of the stratosphere. We…

Analysis of PDEs · Mathematics 2020-02-25 Tetu Makino

We demonstrate that there is only one physical process required to explain the spectrum and the variability of the radio source at the dynamical center of our Galaxy, Sgr A*, in the frequency range from $\approx$1 to $\approx$1000 GHz,…

Astrophysics · Physics 2007-05-23 Wolfgang J. Duschl , Harald Lesch

We present an analysis of simultaneous multifrequency measurements of the Galactic emission in the 1-10 GHz range with 18 degrees, angular resolution taken from a high altitude site. Our data yield a determination of the synchrotron…

Astrophysics · Physics 2009-10-30 P. Platania , M. Bensadoun , M. Bersanelli , G. De Amici , A. Kogut , S. Levin , D. Maino , G. F. Smoot

It has recently been claimed, with a $4.2 \sigma$ significance level, that gravitational wave echoes at a frequency of about $72$ Hz have been produced in the GW170817 event. The merging of compact stars can lead to the emission of…

General Relativity and Quantum Cosmology · Physics 2018-06-27 Massimo Mannarelli , Francesco Tonelli

Some results are presented of the Earth's microseismic background. It is assumed that background peaks should correspond to the resonance gravity-wave exchange in the system of two gravity-connected bodies. The microseismic spectrum is…

Astrophysics · Physics 2007-05-23 V. A. Dubrovskiy

Gamma ray bursts (GRBs) are astronomical phenomena detected at highest energies. The gamma ray photons carry energies on the order of mega-electronovolts and arrive to us from the point-like sources that are uniformly distributed on the…

High Energy Astrophysical Phenomena · Physics 2021-04-21 A. Janiuk , B. James , K. Sapountzis

We investigate the gravitational wave background produced by magnetars. The statistical properties of these highly magnetized stars were derived by population synthesis methods and assumed to be also representative of extragalactic objects.…

Astrophysics · Physics 2009-11-16 Tania Regimbau , José Antonio de Freitas Pacheco

Recent observations of cosmic rays (CRs) have revealed a two-component anomaly in the spectra of primary and secondary particles, as well as their ratios, prompting investigation into their common origin. In this study, we incorporate the…

High Energy Astrophysical Phenomena · Physics 2024-03-08 Yu-Hua Yao , Xu-Lin Dong , Yi-Qing Guo , Qiang Yuan

Galactic ultra compact binaries are expected to be the dominant source of gravitational waves in the milli-Hertz frequency band. Of the tens of millions of galactic binaries with periods shorter than an hour, it is estimated that a few tens…

General Relativity and Quantum Cosmology · Physics 2020-07-01 Tyson Littenberg , Neil Cornish , Kristen Lackeos , Travis Robson

Hidden matter that interacts only gravitationally would oscillate at characteristic frequencies when trapped inside of Earth. For small oscillations near the center of the Earth, these frequencies are around 300 $\mu$Hz. Additionally,…

Instrumentation and Methods for Astrophysics · Physics 2020-06-19 Wenxiang Hu , Matthew Lawson , Dmitry Budker , Nataniel L. Figueroa , Derek F. Jackson Kimball , Allen P. Mills , Christian Voigt

Black holes orbiting the Super Massive Black Hole (SMBH) Sgr A* in the Milky-way galaxy center (GC) generate gravitational waves. The spectrum, due to stars and black holes, is continuous below 40 nHz while individual BHs within about 200…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Alak Ray , Bence Kocsis , Simon Portegies Zwart

Gravitational waves from cosmic strings are generated in the first fractions of a second after the Big Bang, potentially providing a unprecedented probe of the early universe. We discuss the key dynamical processes underlying calculations…

Astrophysics · Physics 2007-05-23 R. A. Battye , R. R. Caldwell , E. P. S. Shellard

Observations have recently indicated that the Universe at the present stage is in an accelerating expansion, a process that has great implications. We evaluate the spectrum of relic gravitational waves in the current accelerating Universe…

Astrophysics · Physics 2007-05-23 Yang Zhang , Yefei Yuan , Wen Zhao , Ying-Tian Chen

Gravitational waves are expected to be radiated by supermassive black hole binaries formed during galaxy mergers. A stochastic superposition of gravitational waves from all such binary systems will modulate the arrival times of pulses from…