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相关论文: Analysis of Polar Motion Variations from 170-year …

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Polars are highly magnetic cataclysmic variables which have been long observed to have both high and low brightness states. The duration of these states has been previously seen to vary from a number of days up to years. Despite this; these…

太阳与恒星天体物理 · 物理学 2022-09-14 C. Duffy , G. Ramsay , Kinwah Wu , Paul A. Mason , P. Hakala , D. Steeghs , M. A. Wood

Trends in terrestrial temperature variability are perhaps more relevant for species viability than trends in mean temperature. In this paper, we develop methodology for estimating such trends using multi-resolution climate data from polar…

机器学习 · 统计学 2019-01-23 Arash Khodadadi , Daniel J McDonald

An automatic Bayesian Kepler periodogram has been developed for identifying and characterizing multiple planetary orbits in precision radial velocity data. The periodogram is powered by a parallel tempering MCMC algorithm which is capable…

天体物理学 · 物理学 2008-11-26 P. C. Gregory

In this first of two papers, we present a new method for searching for oscillatory features in the primordial power spectrum. A wide variety of models predict these features in one of two different flavors: logarithmically spaced…

宇宙学与河外天体物理 · 物理学 2014-04-02 P. Daniel Meerburg , David N. Spergel , Benjamin D. Wandelt

Polar vortices are common planetary flows that encircle the pole in the middle or high latitudes, and are observed on most of the solar systems' planetary atmospheres. The polar vortices on Earth, Mars, and Titan are dynamically related to…

地球与行星天体物理 · 物理学 2022-02-28 Ilai Guendelman , Darryn W. Waugh , Yohai Kaspi

We present a large sample of high-precision, coherently-dedispersed polarization profiles of millisecond pulsars (MSPs) at frequencies between 410 and 1414 MHz. These data include the first polarimetric observations of several of the…

天体物理学 · 物理学 2009-10-31 I. H. Stairs , S. E. Thorsett , F. Camilo

Polarimetric studies of pulsar radio emission traditionally concentrate on how the Stokes vector (I, Q, U, V) varies with pulse longitude, with special emphasis on the position angle (PA) swing of the linearly polarized component. The…

太阳与恒星天体物理 · 物理学 2011-03-08 C. T. Y. Chung , A. Melatos

Estimating high resolution models of the Earth's core magnetic field and its time variation in the polar regions requires that one can adequately account for magnetic signals produced by polar ionospheric currents, which vary on a wide…

空间物理 · 物理学 2023-09-11 Clemens Kloss , Christopher C. Finlay , Karl M. Laundal , Nils Olsen

Light travel time changes due to gravitational waves may be detected within the next decade through precision timing of millisecond pulsars. Removal of frequency-dependent interstellar medium (ISM) delays due to dispersion and scattering is…

天体物理仪器与方法 · 物理学 2015-12-16 Nipuni Palliyaguru , Daniel Stinebring , Maura McLaughlin , Paul Demorest , Glenn Jones

Drifting subpulse patterns in pulsar signals are frequently interpreted in terms of a model in which a rotating ring of sparks on the polar cap gives rise to emission from regions of the magnetsophere connected to the sparks by dipolar…

天体物理学 · 物理学 2009-11-10 R. T. Edwards , B. W. Stappers

We introduce Multivariate Circulant Singular Spectrum Analysis (M-CiSSA) to provide a comprehensive framework to analyze fluctuations, extracting the underlying components of a set of time series, disentangling their sources of variation…

信号处理 · 电气工程与系统科学 2023-08-24 Juan Bógalo , Pilar Poncela , Eva Senra

We present results regarding the longitudinal migrations of cool stellar spots that exhibit remarkable oscillations and explore their possible causes. We conducted analyses using high-quality data from nine target systems of various…

太阳与恒星天体物理 · 物理学 2024-04-15 N. Ö. Kaya , H. A. Dal

The Parkes multibeam pulsar survey is a sensitive survey of a strip along the Galactic plane with |b|<5 deg and l=260 deg to l=50 deg. It uses a 13-beam receiver on the 64-m Parkes radio telescope, receiving two polarisations per beam over…

Polarization behaviour shows a transition in the pulsar population, where energetic sources with higher spin-down energy loss, $\dot{E} > 10^{34}$ erg~s$^{-1}$, often have fractional linear polarisation ($L/I$) close to 100\%, while below…

高能天体物理现象 · 物理学 2025-05-20 Dipanjan Mitra , Rahul Basu , George I. Melikidze

Efforts are underway to use high-precision timing of pulsars in order to detect low-frequency gravitational waves. A limit to this technique is the timing noise generated by dispersion in the plasma along the line of sight to the pulsar,…

高能天体物理现象 · 物理学 2022-02-04 P. Kumar , S. M. White , K. Stovall , J. Dowell , G. B. Taylor

Polarization profiles are presented for 20 millisecond pulsars that are being observed as part of the Parkes Pulsar Timing Array project. The observations used the Parkes multibeam receiver with a central frequency of 1369 MHz and the…

Polar brightening (PB) observed at microwave frequencies serves as an important probe to study the thermal and magnetic properties in the Sun's polar regions. Building on earlier studies that linked microwave PB to polar faculae,…

太阳与恒星天体物理 · 物理学 2026-05-08 Rohan Bose , Anshu Kumari , Vaibhav Pant , Srinjana Routh , Divya Paliwal , M. V. Sunil Krishna

Recently several long-period radio transients have been discovered, with strongly polarised coherent radio pulses appearing on timescales between tens to thousands of seconds [1,2]. In some cases the radio pulses have been interpreted as…

With the ever-increasing sensitivity and timing baselines of modern radio telescopes, a growing number of pulsars are being shown to exhibit transitions in their rotational and radio emission properties. In many of these cases, the two are…

高能天体物理现象 · 物理学 2022-05-11 B. Shaw , B. W. Stappers , P. Weltevrede , P. R. Brook , A. Karastergiou , C. A. Jordan , M. J. Keith , M. Kramer , A. G. Lyne

Evidence of past climate variations are stored in ice and indicate glacial-interglacial cycles characterized by three dominant time periods of 20kyr, 40kyr, and 100kyr. We study the scaling properties of temperature proxy records of four…

统计力学 · 物理学 2015-06-24 Yosef Ashkenazy , Don R. Baker , Hezi Gildor , Shlomo Havlin