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We constrain the velocity spectral distribution of global-scale solar convective cells at depth using techniques of local helioseismology. We calibrate the sensitivity of helioseismic waves to large-scale convective cells in the interior by…

Solar and Stellar Astrophysics · Physics 2015-05-18 S. M. Hanasoge , T. L. Duvall , M. L. DeRosa

The observed power spectrum of high-degree solar p-modes (l>200) shows discrepancies with the power spectrum predicted by the stochastic excitement and damping theory. In an attempt to explain these discrepancies, the present paper is…

Astrophysics · Physics 2009-11-11 B. M. Shergelashvili , S. Poedts

The response of a cross-correlation measurement to an isotropic stochastic gravitational-wave background depends on the observing geometry via the overlap reduction function. If one of the detectors being correlated is a resonant bar whose…

General Relativity and Quantum Cosmology · Physics 2009-11-11 John T Whelan

Measurements of the spectrum of the fluctuations of the output current of the quadratic detector of a telescope can be used to find unresolved astronomical gravitational lenses and determine time delays between their image components. These…

Astrophysics · Physics 2009-11-13 Ermanno F. Borra

Solar oscillations consist of a rich spectrum of internal acoustic waves and surface gravity waves, stochastically excited by turbulent convection. They have been monitored almost continuously over the last ten years with high-precision…

Astrophysics · Physics 2010-11-26 L. Gizon

Convection in the solar interior is thought to comprise structures on a spectrum of scales. This conclusion emerges from phenomenological studies and numerical simulations, though neither covers the proper range of dynamical parameters of…

Solar and Stellar Astrophysics · Physics 2015-06-05 Shravan Hanasoge , Thomas L. Duvall , Katepalli R. Sreenivasan

Intensity mapping of the neutral hydrogen (HI) is a new observational tool that can be used to efficiently map the large-scale structure of the Universe over wide redshift ranges. The power spectrum of the intensity maps contains…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-23 L. Wolz , C. Tonini , C. Blake , J. S. B. Wyithe

We consider the cross-correlation search for periodic GWs and its potential application to the LMXB Sco X-1. This method coherently combines data from different detectors at the same time, as well as different times from the same or…

General Relativity and Quantum Cosmology · Physics 2015-05-21 John T. Whelan , Santosh Sundaresan , Yuanhao Zhang , Prabath Peiris

Proposed near-future upgrades of the current advanced interferometric gravitational wave detectors include the usage of frequency dependent squeezed light to reduce the current sensitivity-limiting quantum noise. We quantify and describe…

The Advanced LIGO/Virgo interferometers have observed $\sim 100$ gravitational-wave transients enabling new questions to be answered about relativity, astrophysics, and cosmology. However, many of our current procedures for computing these…

General Relativity and Quantum Cosmology · Physics 2023-06-14 Noah E. Wolfe , Colm Talbot , Jacob Golomb

The Solar and Heliospheric Observatory (SOHO) was launched in December 1995 with a suite of instruments designed to answer long-standing questions about the Sun's internal structure, its extensive outer atmosphere, and the solar wind. This…

Astrophysics · Physics 2007-05-23 Steven R. Cranmer

The acoustic cut-off frequency -the highest frequency for acoustic solar eigenmodes- is an important parameter of the solar atmosphere as it determines the upper boundary of the p-mode resonant cavities. At frequencies beyond this value,…

Solar and Stellar Astrophysics · Physics 2015-05-30 A. Jimenez , R. A. Garcia , P. L. Palle

The solar convection manifests as granulation and intergranulation at the solar surface. In the photosphere, convective motions induce differential Doppler shifts to spectral lines. The observed convective blueshift varies across the solar…

Solar and Stellar Astrophysics · Physics 2018-03-14 Johannes Löhner-Böttcher , Wolfgang Schmidt , Franziska Stief , Tilo Steinmetz , Ronald Holzwarth

Solar-like oscillations are expected to be excited in stars of up to about 1.6 solar masses. Most of these stars will have convective cores during their Main-sequence evolution. At the edges of these convective cores there is a rapid…

Solar and Stellar Astrophysics · Physics 2015-05-19 Margarida S. Cunha , Isa M. Brandão

To obtain cm/s precision, stellar surface magneto-convection must be disentangled from observed radial velocities (RVs). In order to understand and remove the convective signature, we create Sun-as-a-star model observations based on a 3D…

Solar and Stellar Astrophysics · Physics 2014-08-22 H. M. Cegla , C. A. Watson , S. Shelyag , M. Mathioudakis

Detecting a stationary, stochastic gravitational wave signal is complicated by impossibility of observing the detector noise independently of the signal. One consequence is that we require at least two detectors to observe the signal, which…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Lee Samuel Finn , Albert Lazzarini

Detection of solar gravity modes remains a major challenge to our understanding of the innerparts of the Sun. Their frequencies would enable the derivation of constraints on the core physical properties while their amplitudes can put severe…

Astrophysics · Physics 2009-11-13 K. Belkacem , R. Samadi , M. J. Goupil , M. A. Dupret , A. S. Brun , F. Baudin

We demonstrate the potential of new adaptive optical technology to expand the detection horizon of gravitational-wave observatories. Achieving greater quantum-noise-limited sensitivity to spacetime strain hinges on achieving higher…

The possibility of compensating atmospheric influence in an experiment on precision measurement of gravitational redshift using the "RadioAstron" spacecraft (SC) is discussed. When a signal propagates from a ground-based tracking station to…

Instrumentation and Methods for Astrophysics · Physics 2019-12-11 Valentin Rudenko , Sergei Popov , Aleksei Belonenko

Context: Helioseismology aims to infer the properties of the solar interior by analyzing observations of acoustic oscillations. The interpretation of the helioseismic data is however complicated by the non-trivial relationship between…

Solar and Stellar Astrophysics · Physics 2025-10-29 D. Fournier , N. M. Kostogryz , L. Gizon , J. Schou , V. Witzke , A. I. Shapiro , I. Milic