Re: ATM Focal plane strobe

["Howard Banich" <hbanich@teleport.com>]

Clive,

Several of us in the Rose City Astronomers (Portland, Oregon) tried this a
couple of winters ago - we wanted to see if we could visually "turn off" the
pulsar. Two devices were made, the biggest challenge being making them
vibration free. Once that was solved it became apparent that we needed a
bigger telescope since the effect of strobing dimmed the overall image too
much to see the 16th magnitude pulsar. We tried up to a 30" scope with no
success, but it was sure fun trying!

I'm not certain, but recall that the strobing was somewhere around 30 blinks
per second, the same rate that the pulsar rotates, and the strobing devices
were tunable to be able to match the rate precisely. Bob Bond and Dan
Petersen made the two devices, and I think we all came away from the effort
thinking we just needed more aperture.

Howard
Forest Grove, Oregon

-----Original Message-----
From: Clive Milne <milnecd@wantree.com.au>
To: atm@shore.net <atm@shore.net>
Date: Thursday, August 19, 1999 9:48 PM
Subject: ATM Focal plane strobe

>    Has anyone on the list succesfully constructed a device for strobing
the
>Neutron star at the heart of the Crab SNR..? ... Interested in knowing what
>window / opacity ratio is reccomended...?
>    Cheers
>        Clive.....
>    I suppose I should also ask.... frequency..?