Re: Tagger interface drawing (fwd from Jay)

[Elton Smith <elton@jlab.org>]

---------- Forwarded message ----------
Date: Fri, 11 Jan 2008 09:09:12 -0500
From: Jay Benesch <benesch@jlab.org>
To: Tim Whitlatch <whitey@jlab.org>
Cc: Elton Smith <elton@jlab.org>, halld-tagger@jlab.org,
     Tommy Hiatt <hiatt@jlab.org>, Mark Wiseman <wiseman@jlab.org>
Subject: Re: Tagger interface drawing (fwd)

> Currently we can only get 1.125 in o.d. because of the 30mm aperture quad. Should this grow?

Tim,

Richard answered the question better than I can.

The QP quads for arc 10 and hall D have 1.5" aperture.  They are 30 cm
long and have a gradient limit ~2 (kG/cm)*cm, so they have about twice
the capacity needed if the number I have is correct.  A prototype is
on order.  I don't know if the alignment of the laminations will be
good enough to take a 38mm OD tube.  Unfortunately, the metric tubes I
found at vendors on line are 38+-0.15mm OD and 35+-0.15mm OD with
nothing in between.

It would be really helpful if the ID of the QP were increased to
accept a 38.15mm OD tube.  39mm?  40mm?  Ask the vendor.

Jay


> There are two numbers quoted below: 1.125" o.d. (Tim) and 1.25" i.d. (Jay).  Why are we using the smaller pipe after the radiator, the the delivery beam pipe has the 1.25 o.d.?
>
> All of our tagger background simulations to date have been done with a 1.5" o.d., 1.375" i.d. beam pipe between the radiator and tagger magnet, through the quad.  I would like to know how much it would cost to increase the gap spec on the quadrupole magnet to 1.5" vs repeating our simulations and revisiting the question of tagger backgrounds with the smaller pipe size.  I could do that if it would result in substantial savings in the quadrupole cost.
>
> Richard Jones
>
> Tim Whitlatch wrote:
>> Currently we can only get 1.125 in o.d. because of the 30mm aperture quad. Should this grow?
>>
>> Tim
>>
>> Elton Smith wrote:
>>> Thanks, Elton.
>>>
>>> Elton Smith
>>> Jefferson Lab MS 12H5
>>> 12000 Jefferson Ave
>>> Suite # 16
>>> Newport News, VA 23606
>>> elton@jlab.org
>>> (757) 269-7625
>>>
>>> On Thu, 10 Jan 2008, Jay Benesch wrote:
>>>
>>>
>>>> The quads in the hall D line will have 1.375" OD, 1.25" ID beam pipes.
>>>>   The tagger quad beam pipe should be as close to this as possible.
>>>>
>>>> Jay
>>>>
>>>>
>>>>