Related papers: The NANOGrav 11-year Data Set: Solar Wind Sounding…
Recently, Pulsar Timing Arrays (PTAs) reported a signal at nanohertz frequencies consistent with a stochastic gravitational wave background. Here, I show that the Brownian motion of the Sun as a result of its random gravitational…
Pulsar timing arrays (PTAs) use an array of millisecond pulsars to search for gravitational waves in the nanohertz regime in pulse time of arrival data. This paper presents rigorous tests of PTA methods, examining their consistency across…
The solar wind flow creates a wake behind any spacecraft immersed in it. We study the properties of this wake using the spherical electrostatic probes of the Electric Fields and Waves (EFW) instruments on the Cluster satellites. The…
We present high-cadence observations and simulations of the solar photosphere, obtained using the Rapid Oscillations in the Solar Atmosphere imaging system and the MuRAM magneto-hydrodynamic code, respectively. Each dataset demonstrates a…
Large amplitude whistler waves at frequencies of 0.2 to 0.4 times electron cyclotron frequency are frequently observed in the solar wind. The waves are obliquely propagating close to the resonance cone, with significant electric fields…
Noise characterization for pulsar-timing applications accounts for interstellar dispersion by assuming a known frequency-dependence of the delay it introduces in the times of arrival (TOAs). However, calculations of this delay suffer from…
The ratio of the rms electron density fluctuations to the background density in the solar wind (density modulation index, $\epsilon_{N} \equiv \Delta{N}/N$) is of vital importance in understanding several problems in heliospheric physics…
Analysis of pulsar timing data have provided evidence for a stochastic gravitational wave background in the nHz frequency band. The most plausible source of such a background is the superposition of signals from millions of supermassive…
Using data collected by the Indian Mars Orbiter Mission in October 2021, we investigated coronal regions of the Sun by analyzing the Doppler spectral width of radio signals to estimate solar wind velocity. A simplified equation is…
The recent evidence of nanohertz (nHz) gravitational wave (GW) background by pulsar timing array (PTA) collaborations has sparked considerable interest in understanding its astrophysical origins, particularly regarding supermassive black…
We obtain scatter broadened images of the Crab Nebula at 80 MHz as it transits through the inner solar wind in June 2016 and 2017. These images are anisotropic, with the major axis oriented perpendicular to the radially outward coronal…
The outer heliosphere is a dynamic region shaped largely by the interaction between the solar wind and the interstellar medium. While interplanetary magnetic field and plasma observations by the Voyager spacecraft have significantly…
In this paper, we analyze the probability density function (PDF) of solar wind velocity and proton density, based on generalized thermostatistics (GT) approach, comparing theoretical results with observational data. The time series analyzed…
Whistler waves are intermittently present in the solar wind, while their origin and effects are not entirely understood. We present a statistical analysis of magnetic field fluctuations in the whistler frequency range (above 16 Hz) based on…
The properties of the solar wind, as measured in situ throughout the heliosphere, depend both on the characteristics of its coronal source and on the intrinsic processes governing its interplanetary evolution. Recently, radial and Parker…
Pulsar timing array experiments search for phenomena that produce angular correlations in the arrival times of signals from millisecond pulsars. The primary goal is to detect an isotropic and stochastic gravitational wave background. We use…
The mergers of supermassive black hole binaries (SMBHBs) promise to be incredible sources of gravitational waves (GWs). While the oscillatory part of the merger gravitational waveform will be outside the frequency sensitivity range of…
We analyze low and high--latitude fast solar wind data from the Ulysses spacecraft from 1992 to 1994 using a a systematic method to analyse the anisotropic content of the magnetic field fluctuations. We investigate all available…
In-situ observations of magnetic field fluctuations in the solar wind show a broad continuum in the power spectral density (PSD) with a power-law range of scaling often identified as an inertial range of magnetohydrodynamic turbulence.…
Solar wind magnetic fluctuations exhibit anisotropy due to the presence of a mean magnetic field in the form of the Parker spiral. Close to the Sun, direct measurements were not available until the recently launched Parker Solar Probe (PSP)…