Re: tagger field map

[Alexander Somov <somov@jlab.org>]

Hello Elke,

Ok, thanks, I also think that it's the simplest dicision.

Yang, could you double check the shift (just to be consistent);
I estimated it to be dz = ~19.6 cm.

Cheers,
        Sascha




On Mon, 12 Jan 2009, Elke-Caroline Aschenauer wrote:

> On Mon, 12 Jan 2009, Alexander Somov wrote:
>
> Dear Sascha,
>
> as Tim already pointed out, we shift our things.
> the tagger magnet and if needed also the quad. This is easiest because it
> does not involve any other parties like the machine group. And there is
> enough space in the tagger hall to do that, so please take this mail as a
> decission.
>
> thanks elke
>
>
>
>> Date: Mon, 12 Jan 2009 09:24:57 -0500 (EST)
>> From: Alexander Somov <somov@jlab.org>
>> To: Tim Whitlatch <whitey@jlab.org>
>> Cc: Guangliang Yang <y.guangliang@physics.gla.ac.uk>, halld-tagger@jlab.org
>> Subject: Re: tagger field map
>>
>>
>> Good morning,
>>
>> Yang thanks for the information.
>>
>> The question is should we shift the magnets or the
>> electron beam pipe which goes to the dump (downstream
>> by 19.6 cm)?
>>
>> Should we shift the quadrupole magnet as well (or one can
>> simply change the quadrupole's field) ?
>>
>> Cheers,
>>         Sascha
>>
>>
>>
>>
>>
>>
>>
>>
>> On Mon, 12 Jan 2009, Tim Whitlatch wrote:
>>
>>> Good morning all,
>>>
>>> We do not wish to change the Tagger hall. Is there an exact number that we
>>> should shift the magnet by? Or is 20cm fine?
>>>
>>> Thanks,
>>>
>>>      Tim
>>>
>>> Guangliang Yang wrote:
>>>> Dear Sascha,
>>>>
>>>>    The number in table 4.2 was calculated for the two dipole tagger. It is
>>>> not correct for the single magnet tagger.  If we don't want to change the
>>>> tagger hall design, we should shift the tagger downstream by ~20 cm.
>>>>
>>>>
>>>> Cheers
>>>>
>>>> Yang
>>>>
>>>>
>>>>
>>>> ----- Original Message ----- From: "Alexander Somov" <somov@jlab.org>
>>>> To: "Richard Jones" <richard.t.jones@uconn.edu>
>>>> Cc: <halld-tagger@jlab.org>
>>>> Sent: Friday, January 09, 2009 3:53 PM
>>>> Subject: tagger field map
>>>>
>>>>
>>>>>
>>>>> Hello Richard,
>>>>>
>>>>> The magnetic field map in the tagger hall seems
>>>>> to be shifted by a few cm in the MC.
>>>>>
>>>>> According to the table 4.2 in the technical design
>>>>> report (updated for the review), the position of
>>>>> 12 GeV electrons at z=26.301 m should be x = -4.7576 m.
>>>>> However, I get x = -4.803 m, see the plot attached.
>>>>> Are the numbers in the table 4.2 correct ?
>>>>>
>>>>> I used the same reconstruction code as before but just
>>>>> replaced the magnetic field map (do I need to shift the
>>>>> map ?)
>>>>>
>>>>> Could you please check. I want to finish with updating
>>>>> geometry asap.
>>>>>
>>>>> Thanks,
>>>>>        Sascha
>>>>>
>>>>> P.S. The full-energy deflection angle in the magnet is
>>>>> correct, 13.4 deg.
>>>>>
>>>>>
>>>>
>>>
>>
>>
>
> ( `,_' )+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=
>  )    `\                                                  -
> /    '. |                                                  +
> |       `,              Elke-Caroline Aschenauer            =
>  \,_  `-/                                                    -
>  ,&&&&&V         Jefferson Lab                                +
> ,&&&&&&&&:       HALL-D 12C / F381       121-A Atlantic Avenue =
> ,&&&&&&&&&&;      Suite 8                 Hampton, VA 23664      -
> |  |&&&&&&&;\     12000 Jefferson Ave                             +
> |  |       :_) _  Newport News, VA 23606  Tel.:  001-757-224-1216  =
> |  |       ;--' | Mail:  elke@jlab.org    Mobil: 001-757-256-5224   -
> '--'   `-.--.   |                                                    +
>   \_    |  |---' Tel.:  001-757-269-5352                             =
>     `-._\__/     Fax.:  001-757-269-6331                              -
>            +=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+
>
>