Chandra smells a RRAT

Gaensler, B. M.; McLaughlin, Maura; Reynolds, Stephen P.; Borkowski, K. J.; Rea, N.; Possenti, A.; Israel, G. L.; Burgay, M.; Camilo, F.; Chatterjee, Shami; Krämer, M.; Lyne, A. G.; Stairs, I. H.

doi:10.1007/978-1-4020-5998-8_13

Cited by 2 publications

(2 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Indeed, for instance the RRAT PSR J0627+16, which was found via its individual pulses, showed weak emission in a follow-up observation (Deneva et al 2009) and the sum of the individual bursts of the RRAT PSR J1819-1458 produces a triple peaked pulse profile which is much wider than the individual bursts (Karastergiou et al 2009). The latter RRAT shows a X-ray spectrum which is consistent with thermal emission from a cooling neutron star (Reynolds et al 2006;Gaensler et al 2007) and, like PSR B0656+14, it shows X-ray pulsations (McLaughlin et al 2007). As will be discussed later in this paper, the peculiar emission properties of PSRs J1119-6127 and B0656+14 might be linked to the erratic emission seen for other young and energetic pulsars, such as the Vela pulsar and PSR B1706-44 (Johnston et al 2001;Johnston & Romani 2002), thereby providing some generalization between the different phenomenon.…”

Section: Introductionmentioning

confidence: 52%

The glitch-induced identity changes of PSR J1119−6127

Weltevrede

Johnston

Espinoza

2010

Monthly Notices of the Royal Astronomical Society

193

191

View full text Add to dashboard Cite

Rotation-powered radio pulsars are generally observed to pulse regularly in the radio band, but this is not the case for so-called rotating radio transients (RRATs) which emit only sporadic bursts of radio emission. We demonstrate that the high-magnetic field pulsar J1119−6127 exhibits three different types of behaviour in the radio band. Trailing the 'normal' profile peak there is an 'intermittent' peak and these components are flanked by two additional components showing very erratic 'RRAT-like' emission. Both the intermittent and RRAT-like events are extremely rare and are preceded by a large amplitude glitch in the spin-down parameters. The post-glitch relaxation occurs on two different time-scales (∼20 and ∼210 d) and the post-glitch spin-down rate is smaller than the pre-glitch rate. This type of relaxation is also seen in an earlier, smaller glitch and is very unusual for the pulsar population as a whole, but is observed in the glitch recovery of an RRAT. The abnormal emission behaviour in PSR J1119−6127 was observed up to three months after the epoch of the large glitch, suggestive of changes in the magnetospheric conditions during the fast part of the recovery process. We argue that both the anomalous recoveries and the emission changes could be related to reconfigurations of the magnetic field. Apart from the glitches, the spin-down of PSR J1119−6127 is relatively stable, allowing us to refine the measurement of the braking index (n = 2.684 ± 0.002) using more than 12 yr of timing data.The properties of this pulsar are discussed in light of the growing evidence that RRATs do not form a distinct class of pulsar, but rather are a combination of different extreme emission types seen in other neutron stars. Different sub-classes of the RRATs can potentially be separated by calculating the lower limit on the modulation index of their emission. Unlike other quantities, this parameter is independent of observation duration allowing a direct comparison with other emission phenomena. We speculate that if the abnormal behaviour in PSR J1119−6127 is indeed glitch induced then there might exist a population of neutron stars which only become visible in the radio band for a short duration in the immediate aftermath of glitch activity. These neutron stars will be visible in the radio band as sources that only emit a cluster of pulses once every few years.

show abstract

Section: Introductionmentioning

confidence: 52%

The glitch-induced identity changes of PSR J1119−6127

Weltevrede

Johnston

Espinoza

2010

Monthly Notices of the Royal Astronomical Society

193

191

View full text Add to dashboard Cite

show abstract

“…Their second model interpreted RRATs' behavior as a complement to nulling pulsars undergoing a reversal of radio emission direction. Zhang et al proposed that X-ray observations may help discern between the two interpretations and specifically mention PSR J1819−1458 as fitting within the re-activated dead pulsar model because of its apparent lack of a non-thermal component in its X-ray spectrum (Reynolds et al, 2006;Gaensler et al, 2007). Even though we are currently unable to constrain a power-law tail, the tentative correlation between the radio pulse and X-ray photon detection times suggests the reactivation model for PSR J1819−1458.…”

Section: Discussionmentioning

confidence: 99%

Multiwavelength Studies of Rotating Radio Transients

Miller

View full text Add to dashboard Cite

Seven years ago, a new class of pulsars called the Rotating Radio Transients (RRATs) was discovered with the Parkes radio telescope in Australia (McLaughlin et al., 2006). These neutron stars are characterized by strong radio bursts at repeatable dispersion measures, but not detectable using standard periodicity-search algorithms. We now know of roughly 100 of these objects, discovered in new surveys and re-analysis of archival survey data. They generally have longer periods than those of the normal pulsar population, and several have high magnetic fields, similar to those other neutron star populations like the X-ray bright magnetars. However, some of the RRATs have spin-down properties very similar to those of normal pulsars, making it difficult to determine the cause of their unusual emission and possible evolutionary relationships between them and other classes of neutron stars. We have calculated single-pulse flux densities for eight RRAT sources observed using the Parkes radio telescope. Like normal pulsars, the pulse amplitude distributions are well described by log-normal probability distribution functions, though two show evidence for an additional power-law tail. Spectral indices are calculated for the seven RRATs which were detected at multiple frequencies. These RRATs have a mean spectral index of α SI = −3.2(7), or α SI ln = −3.1(1) when using mean flux densities derived from fitting log-normal probability distribution functions to the pulse amplitude distributions, suggesting that the RRATs have steeper spectra than normal pulsars. When only considering the three RRATs for which we have a wide range of observing frequencies, however, α SI and α SIln become −1.7(1) and −2.0(1), respectively, and are roughly consistent with those measured for normal pulsars. In all cases, these spectral indices exclude magnetar-like flat spectra. For PSR J1819−1458, the RRAT with the highest bursting rate, pulses were detected at 685 and 3029 MHz in simultaneous observations and have a spectral index consistent with our other analysis. We also present the results of simultaneous radio and X-ray observations of PSR J1819−1458. Our 94-ks XMM-Newton observation of the high magnetic field (∼5×10 9 T) pulsar reveals a blackbody spectrum (kT ∼ 130 eV) with a broad absorption feature, possibly composed of two lines at ∼1.0 and ∼1.3 keV. We performed a correlation analysis of the X-ray photons with radio pulses detected in 16.2 hours of simultaneous observations at 1 − 2 GHz with the Green Bank, Effelsberg, and Parkes telescopes, respectively. Both the detected X-ray photons and radio pulses appear to be randomly distributed in time. We find tentative evidence for

show abstract

Chandra smells a RRAT

Cited by 2 publications

References 20 publications

The glitch-induced identity changes of PSR J1119−6127

The glitch-induced identity changes of PSR J1119−6127

Multiwavelength Studies of Rotating Radio Transients

Contact Info

Product

Resources

About