electron beam dump (fwd)

[Elton Smith <elton@jlab.org>]

Charlie,

Thanks for this additional information. Getting useful comments like this
is one good reason for circulating information among a broad audience.

Cheers, Elton.

-------- Original Message --------
Subject: (no subject)
Date: Fri, 30 Jun 2000 15:19:04 -0400
From: Charles Sinclair <sinclair@jlab.org>
To: wolin@jlab.org

Elliott,

    I just read through your recent e-mail regarding Hall D stuff and
had a couple comments.

    First of all, there is a 120 kW electron dump located in the north
linac "stub" which was used in commissioning days.  It has its closed
circuit water system attached, along with a lot of steel shielding (for
neutrons).  As far as I know, there is no reason why you could not use
all or any part of this system for your 60 kW dump.  That dump is just
like the one in the BSY, and is rated well above the 60 kW you need.
One would need to look at the 1 MW for 1 second case - that is a pretty
demanding requirement.

    You indeed need to think about hydrogen generation in the dump
cooling water, but it should not be a big deal for you compared to the 1
MW dumps we have in the end stations.  For the record,  The hydrogen
generation rate is 0.3 gaseous liter (at stp) of molecular hydrogen
generated per megajoule of beam energy dumped in the water.  In the case
of the north stub dump (and the BSY dump) all the primary beam energy is
dumped in solid metal.   Thus, the water sees only thermal energy, not
beam energy, and there is no hydrogen generation.  That is one of the
nice things about these dumps.

    Anyway, I hope this information is helpful to you.  I can fill you
in with further details about the dumps if you are interested at some
point.


Charlie Sinclair