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Hi Vincenzo,<br>
<br>
To simplify the heating setup, the N2 could be heated by a dedicated
electric gas heater and controlled with a thermostat prior to entry
into the RICH volume. The N2 supply lines may need insulation.<br>
<br>
Question - Would this increased temperature have any effect on the
mirror alignment? or any other component?<br>
<br>
George<br>
<br>
<div class="moz-cite-prefix">On 12/4/2017 9:46 AM, Vincenzo
Lucherini wrote:<br>
</div>
<blockquote type="cite"
cite="mid:227ebd5ef6869c8035f4300bc707ecf4@webmail.lnf.infn.it">thank
you George,
<br>
<br>
- when the RICH is not in operation, there will be no need to flux
the cooling air as we know that in this case it is the Nitrogen
leaking from the RICH to the EP and not the air entering the RICH
from the EP. Only when we flux air in the EP at (total) levels
above 400-500 l/m we see this contamination.
<br>
<br>
- calculations are needed to tell how many degrees such warming
would be considering the Rich volume and its room temp, the
employed Nitrogen flux and it temperature when leaving the EP, but
even few degrees will be beneficial to reduce the RE in the RICH
(by the way, also calculations are needed to quantify the extra
cooling in the EP by "cold" Nitrogen circulation).
<br>
<br>
the point, is that, if the if calculations prove a significant
effect, we could have had "two hits with one shot"... So in my
opinion, they are worth to be done.
<br>
<br>
<br>
<br>
Il 2017-12-04 09:30 George Jacobs ha scritto:
<br>
<blockquote type="cite">Hi Vincenzo,
<br>
<br>
Since the setup you describe would only work during detector
<br>
operation, what about when it's not operating? These detectors
will
<br>
not be used 24-7, 365. Most likely these detector will see far
less
<br>
that 50% operation.
<br>
<br>
The gas volume of the RICH is large compared to the nitrogen
flow.
<br>
Have you considered that the volume is too large to warm using
just
<br>
the incoming N2 flow?
<br>
<br>
George
<br>
<br>
On 12/4/2017 9:11 AM, Vincenzo Lucherini wrote:
<br>
<br>
<blockquote type="cite">Hi George,
<br>
<br>
I would appreciate your comments (when you have time) on the
<br>
considerations in the attached file.
<br>
<br>
Thanks, Vincenzo
<br>
</blockquote>
<br>
--
<br>
George Jacobs
<br>
Jefferson Lab (TJNAF)
<br>
STE 12
<br>
12000 Jefferson Ave.
<br>
Newport News, VA 23606
<br>
<br>
(office) 757-269-7115
<br>
<br>
(cell) 757-876-0480
<br>
<br>
(email) <a class="moz-txt-link-abbreviated" href="mailto:jacobsg@jlab.org">jacobsg@jlab.org</a>
<br>
<br>
(website) <a class="moz-txt-link-freetext" href="https://userweb.jlab.org/~jacobsg">https://userweb.jlab.org/~jacobsg</a> [1]
<br>
<br>
<br>
Links:
<br>
------
<br>
[1] <a class="moz-txt-link-freetext" href="https://userweb.jlab.org/~jacobsg">https://userweb.jlab.org/~jacobsg</a>
<br>
</blockquote>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
George Jacobs
Jefferson Lab (TJNAF)
STE 12
12000 Jefferson Ave.
Newport News, VA 23606
(office) 757-269-7115
(cell) 757-876-0480
(email) <a class="moz-txt-link-abbreviated" href="mailto:jacobsg@jlab.org">jacobsg@jlab.org</a>
(website) <a class="moz-txt-link-freetext" href="https://userweb.jlab.org/~jacobsg">https://userweb.jlab.org/~jacobsg</a></pre>
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