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If it is desired that results are to be regarded as scientific, then it surely follows that they must be subject to the scientific method. To define what the scientific method is one need not go any further than what is returned when typing in "scientific method definition" into Google search - which returns this (a screenshot is shown below)...
A number of significant points are mentioned: systematic observation and measurement and testing - and most significantly "criticism is the backbone of the scientific method".
So what are the key responsibilities when presenting results in a scientific manner ? The following is a broad outline.
Adherence to Science-based Principles
All results must be consistent with the known laws of physics. There are many texts which contain these laws and develop equations which describe the limits of the process.
Application of Statistics
If the results are marginal, and proper scientific analysis is not applied, we are in the realm of human subjectivity. If one wants to see a result, there will be one. If one is unbiased, there may not be. To sort this out the results must be subjected to statistical analysis and presented as some level of probability of being valid.
Of course, if the results are like this...
...or like this...
..or like this...
... where the S/N is very high, then correlation with the actual period of the pulsar lends strong evidence of the validity of the result and S/N statistics are not needed. Note that these results are very similar to professional results...
...the original graph of Jocelyn Bell's discovery of the first pulsar where a clear periodicity is visible (note: an increase in signal strength caused a downward deflection of the chart recorder needle).
Repeatability
One robust method of sorting the wheat from the chaff is repeatability. All the successful amateurs listed on the home page have demonstrated repeatability. As pointed out in professional literature on the subject there are many terrestrial sources which can mimic quite closely the signal from a pulsar. Pulsars appear regularly in a fixed position on the cosmic sphere, while terrestrial sources will likely have a random existence. By repeating the results the terrestrial sources can be identified. The author has several hundred results which look like a Vela pulsar signal, but fail the repeatability and S/N test. Despite the convincing nature of these results, the author does not claim success, merely that they are encouraging results.
Exclusion Test
Most pulsars spend some portion of each day below the horizon. How large that portion is depends on the pulsar's declination combined with the latitude of the observatory. For the author's HawkRAO location and Vela, the time below the horizon is 6 hours every day.
A simple 'exclusion test' is to acquire data when the pulsar is below the horizon and verify an absence of signal.
Another exclusion test could be done by driving the antenna as if tracking the pulsar, but adjust the declination such that the pulsar is out of the 3 dB beamwidth of the antenna - say in the first null in the beam pattern. This a good test as it includes all possible sources of RFI (tracking motors/electronics and terrestrial RFI) while excluding the pulsar which lies outside the beamwidth. There should be an absence of pulsar signal.
Yet another exclusion test could be done by acquiring 24 hours of data from the antenna pointed at the correct declination of the pulsar, but fixed in position (drift-scan mode) so that the pulsar passes through the beamwidth of the antenna. Then by processing successive slices (say 1 hour duration) of the 24 hours of data it can be demonstrated that the pulsar signal only arises when the pulsar is passing through the antenna beamwidth. An animated graphic of this would be a powerful verification of results.
Such efforts to try and disprove the results increase the validity of the results.
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