[Halla12_software] BaBar magnet yoke question (two more questions then my last email)

[Zhiwen Zhao]

On 02/09/2011 11:30 AM, Eugene Chudakov wrote:
>>>> for the cryo of the coil, there's the outer part made of Iron. It's
>
> The cryo tanks are made from stainless steel, non-magnetic.
I didn't know that. I only notice in geometry file, they are same 
material coded as 210

GPARVOL30  'SOLE'    0  'HALL'    0.    0.    0.    0  'TUBE'  3  1. 1. 1.
GPARVOL31  'CRYO'  210  'SOLE'    0.    0.    0.    0  'TUBE'  3  142. 
177.  192.5
GPARVOL32  'CRYV'  221  'CRYO'    0.    0.    0.    0  'TUBE'  3  147. 
172.  187.5
GPARVOL33  'SCL1'  209  'CRYV'    0.    0.    0.    0  'TUBE'  3  152. 
154.  175.0
>
>> Eugene answered this. one of them is commented out in am file, I will
>> correct it in geometry file.
>
> What was there in the geometry file?
SY02 was not comment out

C --     BaBar barrel yoke simplified
C
GPARVOL41  'SY01'  210  'SOLE'    0.    0.    0.    0  'TUBE'  3  180.0 
186.0  187.2
GPARVOL42  'SY02'  210  'SOLE'    0.    0.    0.    0  'TUBE'  3  185.2 
189.0  187.2
GPARVOL43  'SY03'  210  'SOLE'    0.    0.    0.    0  'TUBE'  3  195.6 
199.6  187.2
GPARVOL44  'SY04'  210  'SOLE'    0.    0.    0.    0  'TUBE'  3  206.0 
210.0  187.2
GPARVOL45  'SY05'  210  'SOLE'    0.    0.    0.    0  'TUBE'  3  216.4 
220.4  187.2
GPARVOL46  'SY06'  210  'SOLE'    0.    0.    0.    0  'TUBE'  3  226.8 
230.8  187.2
GPARVOL47  'SY07'  210  'SOLE'    0.    0.    0.    0  'TUBE'  3  237.0 
246.0  187.2
GPARVOL48  'SY08'  210  'SOLE'    0.    0.    0.    0  'TUBE'  3  255.6 
264.6  187.2
GPARVOL49  'SY09'  210  'SOLE'    0.    0.    0.    0  'TUBE'  3  275.0 
290.0  187.2

>
> Eugene
>
>
> On Wed, 9 Feb 2011, Zhiwen Zhao wrote:
>
>> On 02/09/2011 10:30 AM, Paul E. Reimer wrote:
>>> Hello Zhiwen,
>>>
>>>> 1.
>>>> I notice the there is a overllap between two parts of yoke just around
>>>> the coil, as you can see from the lines of the am file
>>> I'll have to look at this in more detail
>> Eugene answered this. one of them is commented out in am file, I will
>> correct it in geometry file.
>>>>
>>>> 2.
>>>> for the cryo of the coil, there's the outer part made of Iron. It's
>>>> not included in AM file. But I think it should because it will affect
>>>> the field. Or is there other reasons to exclude it?
>>> I don't know what the material is.
>> shape materiel inner outer half length
>> Tube Iron 142. 177. 192.5
>> Tube Air 147. 172. 187.5
>> Tube Al 152. 154. 175.0
>>>> 3.
>>>> Both PVDIS and SIDIS used Babar magnets in their first version of
>>>> proposal, then used CDF in the second version. Why is the change?
>>>> Maybe the reason was made clearer before I join in?
>>> In fact, I was under the impression that Babar was used for the
>>> acceptance of both detectors, while CDF was used for the engineering
>>> report. This was because we had engineering reports and access to the
>>> CDF magnet at Argonne and our engineer's worked on this. At the
>>> proposal stage, since we were just dealing with a concept, that seemed
>>> to work.
>> refer to Xin's reply
>>>> 4.
>>>> in SIDIS second version proposal, CDF yoke design was very similar to
>>>> Babar design, only longer. What's the reason you design CDF yoke very
>>>> differently now, Paul?
>>> I spent more time looking at the field shape this time. In particular,
>>> I tried to obtain the same footprint for the detector area with minimal
>>> magnetic field in that area. In reality, the question goes back to the
>>> detector designers--how much space to you need? The other thing that I
>>> did on the recent CDF design is to assume that the target is moved
>>> forward in the magnet.
>> Besides the two end cups, the middle part of the yoke are different.
>> Are those middle part come with magnet so we can't really modify them?
>> BaBar design has many more details in the middle part which I think
>> Eugene did it not only for field but also engineering concern. Do want
>> CDF to take advantage of that?
>>>
>>> Paul
>>>
>> Zhiwen
>>