Hello. I just got a PMT the glass bulb of which has been broken. Even

[Ravaner]

Hello. I just got a PMT the glass bulb of which has been broken. Even if performances are not the best, do you think I can use it as an Electron Multiplier (with all convenient electronics) ?

 

[phyzguy]

No. Photomultiplier tubes require a vacuum in order to operate. If the glass bulb is broken, it no longer has a vacuum inside.

 

[Ravaner]

Hi. I'm aware of that ! I work with an Electron Multiplier under high vacuum but as it arrives to end of life and as I've this broken PMT you better understand my question ...

 

[phyzguy]

Sorry. Then what is your question exactly?

 

[yungman]

Hi. I'm aware of that ! I work with an Electron Multiplier under high vacuum but as it arrives to end of life and as I've this broken PMT you better understand my question ...

You want to ask for help, you better talk nicely.

If you are going to install in vacuum, what do you care whether the glass casing is broken or not, it will be in vacuum. If you can remove the photo sensing stage and get the electron to hit the multiplier, it should work. There is no secret with electron multiplier.

 

[Ravaner]

My question in fact is about cathode that in case of PMT is photon sensitive to generate electrons. Without removing it and placing all that stuff in high vacuum, will this amount of dynodes work as an electron multiplier. I insist without any dynode replacement. My own EM has suffered during an experiment, and may be this substitution will be a low cost operation for almost identical results.

 

[yungman]

I don't know whether you can make it work without removing the cathode and just let the electrons hit the cathode. There is not enough information to answer whether you have enough gain.

There is only one way to find out, put it in and steer the electrons into the PMT. You have nothing to loose, maybe jack up the high voltage a little, and/or increase the gain of the receiving transimpedance amp and see what happen.