12 Inch Cyclotron Phosphor Screens


This is a pictorial history of the phosphor screens used in our cyclotron.

Fig. 1 First phosphor screen we used, ZnS with Au coating

Fig. 2 First beam spot photographed (Sept 16, 1999)

Fig. 3 Spot from chimney based ion source

Fig. 4 vertical betatron motion captured

Fig. 5 Damage to ZnS screen

Fig. 6 Home made P22 Phosphor screens ! Very uniform coating.

Fig. 7 The P22 phosphor screen can resolve individual turns

Fig. 8 The beam was so intense the the P22 illuminated Tim's face through a viewport

Fig. 9 Damage to P22 screen slightly visible under room light

Fig. 10 Damage to P22 screen obvious under UV light

 

Fig. 11 Location of beam deflector system in chamber

Fig. 12 Beam terminates on phosphor screen at end of deflection channel

Fig. 13 View of phosphor screen at end of deflection channel

Fig. 14 We've devised a universal mounting system to accommodate many phosphor plates

Fig. 15 Assortment of phosphor plate arrangements under room light

Fig. 16 Assortment of phosphor plate arrangements under UV light

Fig. 17 View of phosphor screen at end of deflection channel under room light

Fig. 18 Cyclotron is on: halo indicates beam is approaching...

Fig. 19 Intense beam on screen!

Fig. 20 Reducing camera exposure value

Fig. 21 Increasing the deflector voltage brings the beam further onto the screen

Fig. 22 Reducing the camera's EV even more reveals beam structure (multiple turns layers)


Fig. 23 Damage to P22 screen slightly visible under room light


Fig. 24 Damage to P22 screen is obvious under UV light


Fig. 25 A plate to test 6 different phosphors at once

Fig. 26 Multi-phosphor plate under 10 keV X-ray beam


Fig. 27 Multi-phosphor plate under 250 keV ion beam