Unusual glitch activity in the RRAT J1819−1458: an exhausted magnetar?

Abstract

We present an analysis of regular timing observations of the high magnetic field Rotating Radio Transient (RRAT) J1819−1458 obtained using the 64‐m Parkes and 76‐m Lovell radio telescopes over the past 5 years. During this time, the RRAT has suffered two significant glitches with fractional frequency changes of 0.6 × 10−6 and 0.1 × 10−6. Glitches of this magnitude are a phenomenon displayed by both radio pulsars and magnetars. However, the behaviour of J1819−1458 following these glitches is quite different to that which follows glitches in other neutron stars, since the glitch activity resulted in a significant long‐term net decrease in the slow‐down rate. If such glitches occur every 30 years, the spin‐down rate, and by inference the magnetic dipole moment, will drop to zero on a time‐scale of a few thousand years. There are also significant increases in the rate of pulse detection and in the radio pulse energy immediately following the glitches.

Strong pulses detected from rotating radio transient J1819 − 1458

“…From the figure, there is no evidence that the intensity of bimodal bursts undergoes obvious deviation. As reported by Lyne et al (2009) and shown in Fig. 4 (bottom), the timing residuals of RRAT J1819−1458 fall into a triband distribution.…”

The extended X–ray emission around RRAT J1819–1458

“…Using the Xronos package, we folded both X-ray data sets using the radio ephemeris (Lyne et al 2009), confirming the sinusoidal X-ray modulation found with XMMNewton (McLaughlin et al 2007) and Chandra ). In addition, we performed a periodicity search obtaining a Pspin=4.26328(6) s (epoch= MJD 54 617), in agreement with previous work.…”

“…The spin period of RRAT J1819-1458 is 4.3 s (Ṗ ∼ 3.2×10 −13 s s −1 ; Lyne et al 2009), with a characteristic age of 117 kyr and a dipolar magnetic field of B ∼5×10…”

“…Two glitches have ⋆ E-mail: camero@ice.cat been detected, with one of these showing anomalous postglitch recovery that suggests RRAT J1819-1458 originated in the magnetar region of the period-period derivative diagram (Lyne et al 2009). …”

Towards a theory of extremely intermittent pulsars

“…These time scales considerably differ from those observed in PSR B1931+24 and PSR J1841-0500. According to Lyne et al (2009), rotating radio transients could be exhausted magnetars. Most of them occupy the region of the P-Ṗ diagram with periods of several seconds andṖ higher than 10 −14 , although one is surprisingly found in the region of normal radio-pulsars.…”