Date: Fri, 19 Nov 1999 14:16:08 -0500

Author: Gerald Zani

Subject: Re: Crooke's Tube


The amount of radiation is proportional to the power. What do you use as a
power supply? JZ

At 11:43 AM 11/19/99 -0700, you wrote:
>The radiation protection officer tested out tubes for soft x-rays. All of
>our tubes passed, had less than .5mR/h at 5 cm, except for the Crookes Tube.
>It looks like K1-12 at the Maryland site, or is the one used in PIRA
>5H30.15. At 2 m away it could not be distinguished from background
>radiation. At 1 m away it had x-rays of .5 mR/h. At 5 cm it read 5 mR/h.
>This high a level required a sign saying caution - radiation area. Now the
>apparatus is in the process of being registered as a hazardous apparatus and
>would require that a radiation badge be worn etc. If anyone else has had
>their Crookes tube tested I would be interested in the results.
>The tube in the picture at the Maryland site looked like it had metal
>shields at the end of the tube that is not present on ours. I don't think
>this would completely solve the problem since the readings were high on the
>"view" side of the tube.
>What is the best apparatus for showing an electron beam deflected by a
>Jim Krider
>Physics and Astronomy Instructional Resource Team
>Arizona State University Department of Physics and Astronomy
>PO Box 871504, Bldg. PS Rm. F470,Tempe, Arizona 85287-1504
>Phone: 480-965-8086 FAX: 480-965-7954