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RE: electronic dosimeter for 100 nsec pulses
Since neither Les nor I saved the original inquiry, I am forwarding this
via Radsafe.
>Date: Tue, 16 Dec 1997 11:55:12
>To: Lester.Slaback@nist.gov
>From: Andy Hull <hull@mail.sep.bnl.gov>
>Subject: RE: electronic dosimeter for 100 nsec pulses
>
>Les,
>I do not have Myung Chul Jo's e-mail address at hand. Can you forward
this item from Ed Lessard, who is head of Safety at our Alternating
Gradient Synchotron?
>Thanks,
>Andy
>
>
>
>>Return-path: <lessard@BNLDAG.AGS.BNL.GOV>
>>Envelope-to: hull@mail.sep.bnl.gov
>>Delivery-date: Mon, 15 Dec 1997 13:35:08 -0500
>>Return-receipt-to: lessard@BNLDAG.AGS.BNL.GOV
>>Date: Mon, 15 Dec 1997 13:31:15 -0500
>>From: "Edward T. Lessard" <lessard@BNLDAG.AGS.BNL.GOV>
>>Subject: RE: electronic dosimeter for 100 nsec pulses
>>To: 'Andy Hull' <hull@mail.sep.bnl.gov>
>>
>>Hi Andy:
>>
>>I am not a part of Radsafe. I don't know what that is. However, I do
know we use
>>Fermilab designed ion chambers in pulsed radiation fields. Our
experience in fast beam
>>mode with 100 nsec pulse widths of hadrons, leptons and photons is good.
>>The instruments work at 100 nsec but I think they under-respond when you
go to shorter pulse
>>widths. They are very reliable in the 1 mrem/h level up to 25 rem/h
range with photons. I
>>know they are very accurate with our slow beam where pulse width is 500
msec or so. I
>>think very low energy photons would have trouble penetrating the
instrument wall.
>>
>>I refer you to commercial outfits that makes these ion chambers now.
They are:
>>
>>LND Inc
>> 3230 Lawson Boulevard
>> Oceanside NY 11572
>>516-678-6141
>>Fax 516-678-6704
>> TGM Dectectors INC
>> 160 Bear Hill Road
>> Walthaam MA 02154-1075
>>617-890-2090
>>Fax 617-8904711
>>
>>They will customize to your needs.
>>
>>Ed
>>
>>
>>-----Original Message-----
>>From: Andy Hull [SMTP:hull@mail.sep.bnl.gov]
>>Sent: Monday, December 15, 1997 12:47 PM
>>To: lessard1@bnl.gov
>>Subject: re: electronic dosimeter for 100 nsec pulses
>>
>>Ed,
>>I don't know whether or not you're on Radsafe? This recent inquiry on it
>>reminded me that years back this was a concern in accelerator area
monitoring.
>>Do you have any light to shed on it?
>>Andy
>>
>>
>>>Return-path: <server@romulus.ehs.uiuc.edu>
>>>Envelope-to: hull@mail.sep.bnl.gov
>>>Delivery-date: Fri, 28 Nov 1997 10:28:36 -0500
>>>Date: Fri, 28 Nov 1997 09:29:51 -0600 (CST)
>>>Errors-To: melissa@romulus.ehs.uiuc.edu
>>>Reply-To: radsafe@romulus.ehs.uiuc.edu
>>>Originator: radsafe@romulus.ehs.uiuc.edu
>>>Sender: radsafe@romulus.ehs.uiuc.edu
>>>From: Lester.Slaback@nist.gov
>>>To: Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
>>>Subject: re: electronic dosimeter for 100 nsec pulses
>>>X-Listprocessor-Version: 6.0c -- ListProcessor by Anastasios Kotsikonas
>>>X-Comment: RADSAFE Distribution List
>>>
>>>Myung Chul Jo says:
>>>
>>>I would appreciate to know what kind and type of electronic dosimeters
>>>are suitable to measure x-ray pulses with 100 nanosecond duration and
>>>expected exposure rate is 50-200 mR/pulse at about 1 meter from target.
>>>The expected x-ray energies are 0-3 MeV. I want to be able to access the
>>>exposure (or rate) immediately without special reader and keep as long as
>>>I want. Area monitors will be in place
>>>but they will require to be processed by outside vendor. I would like to
>>>map radiation fields as quickly as possible in our facility when the unit
>>>starts operating. I have 2 pressurized ion chambers which have integration
>>>mode. I would like to be able to take more than two points/pulse.
>>>
>>>Ted de C. summarized the challenges well. 2 Mrad/s and mrad sensitivity is
>>>a considerable challenge. If a specialized instrument is
>>>available the costs would be such that your objective of doing multiple
>>>points could be done just as cheaply (and probably better) with an
>>>in-house TLD system. A manual basic system would probably cost $15-20K
>>>(this might be wishful dreaming, I have not priced these systems in some
>>>time!) --
>>>the above are the personal musing of the author,
>>>and do not represent any past, current, or future
>>>position of NIST, the U.S. Government, or anyone else
>>>who might think that they are in a position of authority.
>>>NBSR Health Physics
>>>NIST
>>>Gaithersburg, MD 20899
>>>301 975-5810
>>>-----------------------------------------------------------
>>>Lester.Slaback@nist.gov
>>>-----------------------------------------------------------
>>>
>>>
>>>
>>
>>
>>