Re: Tagger interface drawing (fwd)

[Elton Smith <elton@jlab.org>]

HI Richard,

It seems like we need to clarify/educate all parties regarding the
interface between the electron beam and tagger. There is clearly some
confusion.

Cheers, Elton.

Elton Smith
Jefferson Lab MS 12H5
12000 Jefferson Ave
Suite # 16
Newport News, VA 23606
elton@jlab.org
(757) 269-7625

---------- Forwarded message ----------
Date: Fri, 11 Jan 2008 13:22:45 -0500
From: Mark Wiseman <wiseman@jlab.org>
To: Jay Benesch <benesch@jlab.org>
Cc: Tim Whitlatch <whitey@jlab.org>, Elton Smith <elton@jlab.org>,
     Tommy Hiatt <hiatt@jlab.org>
Subject: Re: Tagger interface drawing (fwd)

I don't understand the connection between the QP quad for the
accelerator and anything down beam of the radiator.

Mark


Jay Benesch wrote:
>> 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
>>>>>
>>>>>
>>>>>

-- 
___________________________________________________________
Mark Wiseman
MS 4A
Jefferson Lab
12000 Jefferson Ave.
Newport News, Va. 23606
757-269-7289
Fax 757-269-5279