[time-nuts] Surplus Guidelines, was: Rubidium Standard

[Dr Bruce Griffiths]

Poul-Henning Kamp wrote:
> In message <00c101c71c96$68e097d0$6464a8c0 at hudler.org>, "Jack Hudler" writes:
>
>   
>> What is the blacken from, the rubidium itself?
>>     
>
> Yes, the rubidium enters the glass and that blackens it.
>
>   
>> Hmmm I wonder if a high power laser can liberate enough to make one useable
>> again? I have about 100000 shots left on a 6 megawatt laser.
>>     
>
> I doubt it.  It is not just evaporated on the inside it is actually absorbed
> into the glass.
>
> At least as I understand it.
>
>
>   
That depends on whether the glass is blackened so that its optical 
transmission to a level where the bulb is unusable before all the 
rubidium is absorbed or not.
If there is sufficient residual unabsorbed rubidium remaining in the 
bulb, then it may be possible to use a suitable laser to photobleach the 
absorbed rubidium to create a sufficiently transparent window that the 
bulb may again be usable, at least for a short time. I wouldn't hold out 
too much hope, but it would certainly be interesting to see if it is 
indeed possible to photobleach  the blackened  bulb.

Bruce