----- Original Message -----
From: "Frederick Sparber" <[EMAIL PROTECTED]>
Sent: Friday, April 14, 2006 1:27 PM
- Grounded photo-cathode at the bottom of the tube
The S1 (Cs-CsO- on Ag) Photoemissive surface is the one with the
photon peaks at ~ 330 and ~ 800 nanometers with a threshold of about 1254
nm (1.0 eV IR)
Cr YAG Laser?
http://ssd-rd.web.cern.ch/ssd-rd/Pad_HPD/Principle/photocathodes.htm
0.1 eV electrons have a velocity v = (0.1* 2*1.6e-19/9.1e-31)^1/2 =
1.875e5 meters/sec!
Checked/agreed. That's 10.66 µs for a 2m flight, quite a comfortable thing
to measure.
Electron space charge will act as a "velocity filter" that allows the
higher energy electrons
out,
Agreed, thats' a good thing since we are only interested in the fastest
electrons: they are the only one whose initial velocity we know for sure.
but if there is a repulsive gravity force F(gr) = m*g = = 9.1e-31*9.8
= 8.9e-30 newtons on an electron
and the restraining electric field (E volts/meter)
force F(e) = E*q = 1.6e-19 newtons at E = 1.0 volt/meter, there is a
problem. :-)
What, which restraining electric field, where ???
- Grounded grid at the top of the tube (so tube is fieldless)
Sounds like a Faraday cup approach, Michel.
A Faraday saucer actually (not a joke this time, the positive collecting
plate wouldn't be hollow)
- Plate above the grid connected to positive terminal of a low voltage
power
supply whose negative terminal is grounded.
Time of flight would be time between laser flash and power supply current
pulse wouldn't it?
Yes. But the ~ 5 microseconds/meter 0.1 eV electrons get there ahead of
the S - 0.5 * a* t^2 ~ = 3.0e-10 meters gravity repelled electrons
traveled.
Please explain.
OTOH. if you light pulse it and wait for the "slowpokes" ?
No, as I said we wouldn't know their initial velocity.
Michel
Fred
Michel
P.S. Nice applet indeed!
P.P.S. No I know nothing about vacuum tubes (was born in 57)
----- Original Message -----
From: "Frederick Sparber" <[EMAIL PROTECTED]>
To: <vortex-l@eskimo.com>
Sent: Friday, April 14, 2006 3:56 AM
Subject: Re: Electrogravity & Proton Repulsion of Electrons
> Michel Jullian writes.
>>
>> Ingenious! (Faraday cup and saucer, indeed ;)
>>
> Very British for tea, what? :-)
>>
>> For electrons slow enough not to produce secondary emission I would
have
>> thought a simpler collecting device, not a hollow one, would work: a
grid
>> surrounding a solid conductor, the latter positive wrt the former.
>>
> In vacuum tubes (if you are old enough to remember them)
> they call that the suppressor grid, usually tied
> internally to the cathode.
>>
>> For the ultra-low energy emitter photo-emission should work better
>> than
>> thermo-emission as it will give more homogeneous energies (precisely
>> controlled by incident light wavelength aren't they?)
>>
> I think an LED/or laser could cause low energy-low velocity electron
> emission from a low work function photo-emissive material.
>
> One of Walter Fendt's applets for materials:
>
> http://www.walter-fendt.de/ph14e/photoeffect.htm
>
> Measuring the time-of-flight of the electrons from flash to detection
> at the top/electrometer to determine/prove gravity repulsion might be a
> chore
>
> Fred
>>
>> Michel
>>
>
>
>
