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Related papers: A Study in Frequency-Dependent Effects on Precisio…

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Pulsar Timing Arrays (PTAs) are exceptionally sensitive detectors in the frequency band $\text{nHz} \lesssim f \lesssim \mu\text{Hz}$. Ultralight dark matter (ULDM), with mass in the range $10^{-23}\,\text{eV} \lesssim m_\phi \lesssim…

High Energy Physics - Phenomenology · Physics 2022-09-14 David E. Kaplan , Andrea Mitridate , Tanner Trickle

In pulsar astronomy, detecting effective pulsar signals among numerous pulsar candidates is an important research topic. Starting from space X-ray pulsar signals, the two-dimensional autocorrelation profile map (2D-APM) feature modelling…

Instrumentation and Methods for Astrophysics · Physics 2021-09-08 Longqi Wang , Jing Jin , Lu Liu , Yi Shen

Pulse-to-pulse profile shape variations introduce correlations in pulsar times of arrival (TOAs) across radio frequency measured at the same observational epoch. This leads to a broadband noise in excess of radiometer noise, which is termed…

High Energy Astrophysical Phenomena · Physics 2024-01-10 A. D. Kulkarni , R. M. Shannon , D. J. Reardon , M. T. Miles , M. Bailes , M. Shamohammadi

A search for pulse signals was carried out in a new sky area included in the monitoring program for the search for pulsars and transients. Processing of several months data recorded in six frequency channels with a total bandwidth of 2.5…

High Energy Astrophysical Phenomena · Physics 2022-07-20 V. A. Samodurov , S. A. Tyul'bashev , M. O. Toropov , S. V. Logvinenko

We consider the impact of stochastic perturbations on otherwise coherent oscillations of classical pulsators. The resulting dynamics are modelled by a driven damped harmonic oscillator subject to either an external or an internal forcing…

Solar and Stellar Astrophysics · Physics 2020-01-22 P. P. Avelino , M. S. Cunha , W. J. Chaplin

Time-correlated variations in the pulse profiles of radio pulsars provide insights into changes in their magnetospheres. For a small number of pulsars (~20), these variations have been shown to correlate with spin-down rate. Many of these…

High Energy Astrophysical Phenomena · Physics 2025-05-30 Michael J. Keith , Renée Spiewak , Andrew G. Lyne , Patrick Weltevrede , Danai Antonopoulou , Ben Stappers

Phasor measurement units (PMUs) are widely used for sub-synchronous oscillation monitoring, yet the effect of windowed discrete Fourier transform (DFT)-based phasor estimation on oscillation observability is not fully characterized. This…

Signal Processing · Electrical Eng. & Systems 2026-03-09 Jiahui Yang , Yuru Wu , Haozong Wang , Yu Liu , Biao Sun , Yilu Liu , Clifton Black

We report on an effort to extract and monitor interstellar scintillation parameters in regular timing observations collected for the NANOGrav pulsar timing array. Scattering delays are measured by creating dynamic spectra for each pulsar…

We measure the effects of interstellar scattering on average pulse profiles from 13 radio pulsars with simple pulse shapes. We use data from the LOFAR High Band Antennas, at frequencies between 110 and 190~MHz. We apply a forward fitting…

In axion models, interactions between axions and electromagnetic waves induce frequency-dependent time delays determined by the axion mass and decay constant. These small delays are difficult to detect, limiting the effectiveness of…

High Energy Astrophysical Phenomena · Physics 2025-10-29 Haihao Shi , Zhenyang Huang , Qiyu Yan , Jun Li , Guoliang Lü , Xuefei Chen

With precision pulsar timing, measured values of a large set of pulsar parameters are obtainable. For some of those parameters, such as the time-derivatives of spin or orbital periods (in the case of binary pulsars), the measured values are…

General Relativity and Quantum Cosmology · Physics 2024-05-24 Dhruv Pathak , Debarati Chatterjee

Variations of dispersion measure (DM) have been observed in some binary pulsars, which can not be well explained by the propagation effects, such as turbulence of the interstellar media (ISM) between the Earth and the pulsar. This paper…

Astrophysics · Physics 2007-05-23 B. P. Gong

We present an empirical model for single pulses of radio emission from pulsars based on gaussian probability distributions for relevant variables. The radiation at a specific pulse phase is represented as the superposition of radiation in…

Astrophysics · Physics 2009-11-13 D. Melrose , A. Miller , A. Karastergiou , Q. Luo

The main goal of pulsar timing array experiments is to detect correlated signals such as nanohertz-frequency gravitational waves. Pulsar timing data collected in dense monitoring campaigns can also be used to study the stars themselves,…

In this paper we report multi-frequency measurements of pulse broadening times (tau_d) for nine medium dispersion measure (DM $\approx 150-400$ pc cm$^{-3}$) pulsars observed over a wide frequency range. The low frequency data at 243, 325…

Astrophysics · Physics 2009-11-10 O. Loehmer , D. Mitra , Y. Gupta , M. Kramer , A. Ahuja

We demonstrate experimentally a scheme to measure small temporal delays, much smaller than the pulse width, between optical pulses. Specifically, we observe an interference effect, based on the concepts of quantum weak measurements and weak…

In this paper, we present the linear decomposition method (LDM), which we developed to detect and analyze pulsar profile variations and mode changing behaviour. We developed LDM utilizing the likelihood function approach assuming the…

High Energy Astrophysical Phenomena · Physics 2025-03-07 Longfei Hao , Zhixuan Li , Faxin Shen , Yonghua Xu , Yuxiang Huang , Kejia Lee , Qingzheng Yu , Hongguang Wang

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…

Terrestrial timescales show instabilities due to the physical limitations of the atomic clocks. Stricter environmental isolation and increased numbers of improved cesium clocks and cavity-tuned hydrogen masers have resulted in time scales…

Astrophysics · Physics 2007-05-23 Demetrios N. Matsakis , Roger S. Foster