Observation of a Rapidly Pulsating Radio Source

Hewish, A.; Bell, S.; Pilkington, J. D. H.; Scott, P. F.; Collins, R. A.

doi:10.1007/978-1-4899-6387-1_1

Cited by 26 publications

(24 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Hewish et al . [] observed a pulse radio emission which has the exact period of 1.337 s. At first it was thought to be an instrumental effect, but Bell (one of Hewish's coauthors) considered it to be a novel‐type star. Now we know it was the first discovery of a pulsar.…”

Section: Introductionmentioning

confidence: 99%

Signals of solar cosmic ray flux variations inferred from the noise in raw CCD solar images taken by SOHO/EIT

Park

et al. 2014

JGR Space Physics

View full text Add to dashboard Cite

The noise embedded in the raw data in one scientific discipline has sometimes been proven to be a valuable signal for another discipline, and there are examples throughout science history. The solar images taken by the solid state detectors (CCDs) of the Sun monitoring satellites are usually cleaned by removing the traces of cosmic rays on the raw CCD data files. Thus, while applying the method of removing the cosmic ray traces, we may be able to estimate the cosmic ray flux by counting the number of traces. The net cosmic ray flux is the sum of galactic cosmic rays and solar-originating particles. The latter are seen as highly transient flux changes related to solar eruptions. We can identify this kind of "cosmic ray" event from the association with phenomena revealed in processed solar images, and we show this using the data of SOHO/extreme ultraviolet imaging telescope (EIT). On the other hand, the estimated cosmic ray flux in the steady state is anticorrelated with solar cycle sunspot number. The profiles of estimated solar cosmic ray flux showing significant increase are found to be strongly correlated with the ground neutron monitor ground level enhancements. Additionally, the profile of estimated cosmic ray flux is consistent with that of the GOES P6 channel. It indicates that the particles with energy higher than 80 MeV may mainly produce the tracks on CCD of EIT. In conclusion, the raw solar images are valuable data for estimating both long-term cosmic ray variations and transient solar particles events.

show abstract

Section: Introductionmentioning

confidence: 99%

Signals of solar cosmic ray flux variations inferred from the noise in raw CCD solar images taken by SOHO/EIT

Park

et al. 2014

JGR Space Physics

View full text Add to dashboard Cite

show abstract

“…The first pulsar, marked today as PSR B1919+21, was detected in 1967 at the frequency of 81 MHz by [ 13 ]. Quite quickly it turned out that a rotating neutron star is responsible for the specific variable and very stable signal.…”

Section: Introductionmentioning

confidence: 99%

Finding the Ionospheric Fluctuations Reflection in the Pulsar Signals’ Characteristics Observed with LOFAR

Błaszkiewicz

Flisek

Kotulak

et al. 2020

Sensors

View full text Add to dashboard Cite

Pulsars’ signals reaching the atmosphere can be considered being stable under certain assumptions. In such a case the ionosphere remains the main factor distorting signal from the extraterrestrial sources, particularly if we observe them at long radio waves. In this article we present the results of the analysis of relative peak flux changes for two selected pulsars: PSR J0332+5434 (B0329+54) and PSR J1509+5531 (B1508+55), observed with the long radio wave sensor (The PL612 Low Frequency Array (LOFAR) station in Bałdy), together with the analysis of Rate of TEC (ROT) parameter changes measured with the Global Navigation Satellite Systems (GNSS) sensor (IGS LAMA station (IGS: International GSSN Service)). The main objective of the work is to find if the rapid plasma density (observed with the Rate of Total Electron Content (TEC)) has a counterpart in the pulsar observation characteristics. This focuses the attention on ionosphere influence during pulsar investigations at low radio frequencies. Additionally, what was the aim of this work, our results give reasons for using pulsar signals from LOFAR together with GNSS data as multi instrumental ionosphere state probes. Our results show a clear anti-correlation between the ROT and the pulsar profile’s peak flux trends.

show abstract

“…Since the discovery of pulsars in 1967 (Hewish et al. 1968), and the realization of the basic nature of pulsar-wind nebulae shortly thereafter, pulsars and PWNe have served as fertile fields for the study of relativistic flows and particle acceleration. The problems posed by these objects include the mechanism of generating a relativistic outflow; the nature of that outflow and even its composition; the distribution of energy between particles and magnetic field and the energy distribution among the particles; the nature of highly relativistic shock waves; and many others.…”

Section: Introductionmentioning

confidence: 99%

Hard X-ray emission from pulsar-wind nebulae

Reynolds

2016

J. Plasma Phys.

View full text Add to dashboard Cite

Pulsar-wind nebulae emit an extremely broad spectrum of continuum radiation, from low radio frequencies to TeV gamma rays. The part of the spectral energy distribution (SED) from radio through MeV gamma rays is due to synchrotron emission from a distribution of relativistic electrons (or pairs) which can be described by one or more power laws. This spectrum exhibits that particle energy distribution, responsible also for the higher-energy (GeV–TeV) part of the SED, due to inverse-Compton upscattering of one of three photon fields: the synchrotron spectrum, the cosmic microwave background, or ambient optical/infrared photons. However, in a few sources, primary hadrons may produce GeV–TeV gamma rays through the decay of neutral pions produced in inelastic cosmic-ray collisions with thermal gas. The higher-energy end of the particle spectrum, producing synchrotron photons above approximately 10 keV, holds clues to the particle acceleration process. However, its detailed study requires imaging spectroscopy in this energy range, not available until the NuSTAR mission beginning in 2012, which performs true imaging between 3 and 78 keV with ${\sim}1^{\prime }$ angular resolution. I review NuSTAR observations of the first three pulsar-wind nebulae (PWNe) to be examined in this way: the Crab Nebula, G21.5–0.9 and MSH 15–52. All three show spectral structure not previously known: spectral steepening in certain locations and overall source shrinkage with increasing photon energy. The Crab Nebula has different shrinkage rates along the torus and along the northwest counter-jet. The latter rate is similar to that for both the other sources (FWHM $\propto E^{m}$ with $m\sim -0.2$). I discuss implications of these results for models of particle transport in PWNe.

show abstract

Observation of a Rapidly Pulsating Radio Source

Cited by 26 publications

References 4 publications

Signals of solar cosmic ray flux variations inferred from the noise in raw CCD solar images taken by SOHO/EIT

Signals of solar cosmic ray flux variations inferred from the noise in raw CCD solar images taken by SOHO/EIT

Finding the Ionospheric Fluctuations Reflection in the Pulsar Signals’ Characteristics Observed with LOFAR

Hard X-ray emission from pulsar-wind nebulae

Contact Info

Product

Resources

About