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

[Eugene Chudakov]

>>> 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.

> 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?

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
>