Pulsar B 0656 + 14 a Very Nearby Rrat Source ?

The recently discovered RRAT sources are characterized by very bright radio bursts which, while being periodically related, occur infrequently. We find bursts with the same characteristics for the known pulsar B0656+14. These bursts represent pulses from the bright end of an extended smooth pulse-energy distribution and are shown to be unlike giant pulses, giant micropulses or the pulses of normal pulsars. The extreme peak-fluxes of the brightest of these pulses indicates that PSR B0656+14, were it not so near, could only have been discovered as an RRAT source. Longer observations of the RRATs may reveal that they, like PSR B0656+14, emit weaker emission in addition to the bursts. PSR B0656+14 is one of three nearby pulsars in the middle-age range in which pulsed high-energy emission has been detected. These are commonly known as " The Three Musketeers " (Becker & Trümper 1997), the other two being Geminga and PSR B1055–52. PSR B0656+14 was included in a recent extensive survey of subpulse modulation in pulsars in the northern sky at the Wester-bork Synthesis Radio Telescope (WSRT) by Weltevrede et al. (2006). In the single pulses analysed for this purpose , the unusual nature of this pulsar's emission was very evident, especially the brief, yet exceptionally powerful bursts of radio emission. These extreme bursts of radio emission of PSR B0656+14 are similar to those detected in the recently discovered population of bursting neutron stars. These Rotating RAdio Transients (RRATs; McLaughlin et al. 2006) typically emit detectable radio emission for less than one second per day, causing standard periodicity searches to fail in detecting the rotation period. From the greatest common divisor of the time between bursts, a period has been found for ten out of the eleven sources. The periods (between 0.4 and 7 s) suggest these sources may be related to the radio-quiet X-ray populations of neutron stars, such as magnetars (Woods & Thompson 2006) and isolated neutron stars (Haberl 2004). However, Popov et al. (2006) have shown that the estimated formation rate of magnetars is too low. Furthermore the spectrum of the only RRAT for which an X-ray counterpart has so far been detected (Reynolds et al. 2006) seems to be too cool, too thermal and too dim for a magnetar, but is consistent with a cooling middle-aged neutron star like PSR B0656+14 (Shibanov et al. 2006). Also the pulse period and the slowdown-rate of PSR B0656+14, as well as …