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Environmental seismic disturbances limit the sensitivity of LIGO gravitational wave detectors. Trains near the LIGO Livingston detector produce low frequency (0.5-10 Hz) ground noise that couples into the gravitational wave sensitive…

Instrumentation and Methods for Astrophysics · Physics 2023-11-29 Jane Glanzer , Siddharth Soni , Jaidyn Spoon , Anamaria Effler , Gabriela González

The detection of quasi-periodic sources of gravitational waves requires the accumulation of signal-to-noise over long observation times. If not removed, Earth-motion induced Doppler modulations, and intrinsic variations of the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Patrick R Brady , Teviet Creighton

Large Scale Structures (LSS) in the universe can be traced using the neutral atomic hydrogen HI through its 21cm emission. Such a 3D matter distribution map can be used to test the Cosmological model and to constrain the Dark Energy…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 R. Ansari , J. E. Campagne , P. Colom , J. M. Le Goff , C. Magneville , J. M. Martin , M. Moniez , J. Rich , C. Yèche

High-resolution array detectors are widely used in single-particle tracking, but their performance is limited by excess noise from background light and dark current. As pixel resolution increases, the diminished signal per pixel exacerbates…

Quantum Physics · Physics 2025-12-16 Chao-Ning Hu , Jun Xin , Xiao-Ming Lu

Time-varying inhomogeneities on stellar surfaces constitute one of the largest sources of radial velocity (RV) error for planet detection and characterization. We show that stellar variations, because they manifest on coherent, rotating…

Solar and Stellar Astrophysics · Physics 2024-11-08 Lily L. Zhao , Megan E. Bedell , David W. Hogg , Rodrigo Luger

Convective motions in the solar atmosphere cause spectral lines to become asymmetric and shifted in wavelength. For photospheric lines, this differential Doppler shift varies from the solar disk center to the limb. Precise and comprehensive…

Solar and Stellar Astrophysics · Physics 2019-04-10 Johannes Löhner-Böttcher , Wolfgang Schmidt , Rolf Schlichenmaier , Tilo Steinmetz , Ronald Holzwarth

We have performed a specific observational test to measure the effect that the zodiacal light can have on measurements of the spatial fluctuations of the near-IR background. Previous estimates of possible fluctuations caused by zodiacal…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-15 Richard G. Arendt , A. Kashlinsky , S. H. Moseley , J. Mather

We discuss prospects for direct measurement of stochastic gravitational wave background around 0.1-1Hz with future space missions. It is assumed to use correlation analysis technique with the optimal TDI variables for two sets of LISA-type…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Naoki Seto

We investigate the spectrum of stochastic gravitational wave background generated by hybrid topological defects: domain walls bounded by strings and monopoles connected by strings. Such defects typically decay early in the history of the…

Astrophysics · Physics 2009-10-28 Xavier Martin , Alex Vilenkin

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

The sensitivity of aLIGO detectors is adversely affected by the presence of noise caused by light scattering. Low frequency seismic disturbances can create higher frequency scattering noise adversely impacting the frequency band in which we…

Instrumentation and Methods for Astrophysics · Physics 2023-11-13 Siddharth Soni , Jane Glanzer , Anamaria Effler , Valera Frolov , Gabriela González , Arnaud Pele , Robert Schofield

We used long high-quality unresolved (Sun-as-a-star observations) data collected by GOLF and VIRGO instruments on board the ESA/NASA SOHO satellite to investigate the amplitude variation with solar cycle 23 in the high-frequency band (5.7 <…

Solar and Stellar Astrophysics · Physics 2015-05-13 R. Simoniello , W. Finsterle , R. A. Garcia , D. Salabert , A. Jimenez

The Sun supports a rich spectrum of internal waves that are continuously excited by turbulent convection. The GONG network and the MDI/SOHO space instrument provide an exceptional data base of spatially-resolved observations of solar…

Solar and Stellar Astrophysics · Physics 2015-05-14 L. Gizon , A. C. Birch , H. C. Spruit

One of the most promising probes to complement current standard cosmological surveys is the HI intensity map, i.e. the distribution of temperature fluctuations in neutral hydrogen. In this paper we present calculations of the 2-point…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-24 Anut Sangka , David Bacon

The spatio-temporal dynamics of the solar photosphere is studied by performing a Proper Orthogonal Decomposition (POD) of line of sight velocity fields computed from high resolution data coming from the MDI/SOHO instrument. Using this…

Astrophysics · Physics 2009-11-13 A. Vecchio , V. Carbone , F. Lepreti , L. Primavera , L. Sorriso-Valvo , P. Veltri , G. Alfonsi , Th. Straus

Context. The High Resolution Telescope of the Polarimetric and Helioseismic Imager on Solar Orbiter (SO/PHI-HRT) operates in an extreme observational environment, observing the Sun as close as $0.28$ au. The high thermal load and large…

We derive expectations for signatures in the measured travel times of waves that interact with thermal anomalies and jets. A series of numerical experiments that involve the dynamic linear evolution of an acoustic wave field in a solar-like…

Astrophysics · Physics 2011-02-11 Shravan M. Hanasoge , Thomas L. Duvall

Helioseismic holography is an imaging technique used to study heterogeneities and flows in the solar interior from observations of solar oscillations at the surface. Holograms contain noise due to the stochastic nature of solar…

Solar and Stellar Astrophysics · Physics 2018-12-12 Laurent Gizon , Damien Fournier , Dan Yang , Aaron C. Birch , Hélène Barucq

Gravitational wave astronomy is established with direct observation of gravitational wave from merging binary black holes and binary neutron stars during the first and second observing run of LIGO and Virgo detectors. The gravitational-wave…

General Relativity and Quantum Cosmology · Physics 2019-12-24 V. Gayathri , P. Bacon , A. Pai , E. Chassande-Mottin , F. Salemi , G. Vedovato

To detect Earth-mass planets using the Doppler method, a major obstacle is to differentiate the planetary signal from intrinsic stellar variability (e.g., pulsations, granulation, spots and plages). Convective blueshift, which results from…

Solar and Stellar Astrophysics · Physics 2023-10-16 S. Dalal , R. D. Haywood , A. Mortier , W. J. Chaplin , N. Meunier
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