Profile stochasticity in PSR J1909−3744

PSR J1022+1001: Profile Stability & Precision Timing

We present an investigation of the morphology and arrival times of integrated radio pulses from the binary millisecond pulsar PSR J1022+1001. This pulsar is renowned for its poor timing properties, which have been postulated to originate from variability in its average pulse profile. Although a sub-class of long-period pulsars are known to exhibit mode changes that give rise to very large devia...

Stochasticity in evolution.

The debate over the role of stochasticity is central in evolutionary biology, often summarised by whether or not evolution is predictable or repeatable. Here we distinguish three types of stochasticity: stochasticity of mutation and variation, of individual life histories and of environmental change. We then explain when stochasticity matters in evolution, distinguishing four broad situations: ...

Stochasticity in Gene Expression

Radio Profile Instability in the Millisecond Pulsar PSR J0437−4715 due to Spiky Emission

The instability in one of the components of the radio integrated profile (IP) of the millisecond pulsar PSR J0437−4715 is correlated with the occurrence of the spiky emission in that component. It is speculated that the instability in other components is also due to the spiky emission. This might have important implications for interpreting the individual components of the IP as independent bea...

A transient component in the pulse profile of PSR J 0738 − 4042

One of the tenets of the radio pulsar observational picture is that the integrated pulse profiles are constant with time. This assumption underpins much of the fantastic science made possible via pulsar timing. Over the past few years, however, this assumption has come under question with a number of pulsars showing pulse shape changes on a range of timescales. Here, we show the dramatic appear...