sPHENIX discussion of the superconducting solenoid

["Yip, Kin" <kinyip AT bnl.gov>]

Hi,

The Magnet was lifted to the oHCAL yesterday (Oct. 7, 2021) morning (approximately 9:30 – 11:30 am).  You can see a couple pictures from Russel Feder’s slides in a meeting this morning (9-10 am) with the CERN mapper group :

2021-10-8 MAGNET_MAPPING_STATUS (Magnet on oHCAL.pdf  ( Magnet on p.3)    

 

I heard from Chris Pontieri and Frank Toldo that with the survey group directing the “traffic” and everything, it’s almost right when they first put it and the alignment adjustment needed was very little. 

 

This morning, the indico page for the CERN mapper group is :  ​https://indico.bnl.gov/event/13511/

During the meeting, I understand that  the best resolution that CERN group can have radially is :

57 mm/2 and the first point is about 85.5 mm .

In z, it's arbitrary (whatever we want, higher resolution => more time).    John Haggerty told me after the meeting that we’ll probably ask about ~5 cm division which should be enough.

 

During the meeting, the CERN mapper group (led by the leader/translator Burkhard Schmidt) told us that they'll use the 2nd bench/mapper(Atlas mapper) that has been used for mapping Atlas.

{ The other mapper would be used for mapping for Dubna}.     The Atlas mapper is currently about 2.1 m (diameter).   To accommodate the EMCAL ( with inner diameter ~ 1800 mm) and the rail, they plan

to cut it to a diameter 1482 mm.

 

If there is no EMCAL, CERN mapper group doesn't need to modify their mapper and we can have larger area with the magnetic field measurement.  We'll need to decide before the end of this year whether

we'll have EMCAL or not during the measurements (so that the CERN mapper group will have enough time to modify the Atlas mapper).

 

 

Kin