[time-nuts] Time of death-Again

[Magnus Danielson]

On 10/29/2010 03:11 PM, jimlux wrote:
> Hal Murray wrote:
>>>> How about the crab supernova.
>>
>>> Msec pulsars are much more stable - see
>>> http://arxiv.org/pdf/0911.5534 for
>>> some comparisons.
>>
>> You get frequency from pulsars. I think you need something like a
>> (super)nova to establish a start-time so you can convert frequency to
>> time relative to that event.
>>
>>
>
> These pulsars have different rates. Could one use the relative timing of
> two or three pulsars? that is, T=0 is when pulsar A, B, and C are
> coincident. (or is the "beat rate" between them too high to be useful)

That would assume a particular position in space in relation to these. 
The time of coincident will differ with space location since the range 
between them and the point of observation will be different. Is the 
pulse phase coherent from all angles of a pulsar?

You could use pulsars, but you would need to have established your 
location in space and compensated for the biases against the reference 
observation. Also, you would need to handle long-term shift in rate, 
gravitational potential at point of observation etc. etc.

Cheers,
Magnus