Pulsar timing enables the most stringent tests of fundamental physics. By monitoring the pulse times of arrival (ToAs) of an ensemble of stable millisecond pulsars (MSPs), known as a pulsar timing array (PTA), it is possible to detect nanohertz gravitational waves (GWs). The success of GW detection with PTAs requires the highest possible timing precision.
The timing precision of a pulsar is limited by many noise contributions, including those introduced by the pulsar itself, the interstellar medium along the line of sight, and the measurement process. On short timescales, the noise is typically dominated by white noise, which includes radiometer noise, jitter noise, and scintillation noise.
In a study published in The Astrophysical Journal, WANG Shuangqiang at the Xinjiang Astronomical Observatory (XAO) of the Chinese Academy of Sciences, and the collaborators, using the data obtained from the Five-hundred-meter Aperture Spherical Radio Telescope (FAST), carried out a study of white noise in MSPs.
The researchers presented measurements of the radiometer noise, jitter noise, and scintillation noise of 12 MSPs that are part of the International Pulsar Timing Array sample.
They found that different pulsars show different levels of jitter noise. The contribution of scintillation noise is likely negligible, and jitter noise is larger than radiometer noise, making it the dominant component in white noise. Therefore, mitigating the jitter noise is important for the detection of GWs.
A new millisecond pulsar has been found through the collaboration of the National Supercomputing Center in Jinan, and the "Chinese sky-eye," the 500-meter Aperture Spherical radio Telescope (FAST), which marks a new trial success for Chinese supercomputing in this field a...
Recently, LI Zhixuan from Yunnan Observatories of Chinese Academy of Sciences, together with the collaborators, discovered two extra-galactic compact radio cores with separations of less than one arcminute to the famous millisecond pulsar PSR J0437–4715. These two radio ...
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