[lcdds 126] question on field outside the detector

["Seryi, Andrei" <seryi@xxxxxxxxxxxxxxxxx>]

Dear Colleagues, 

This question is addressed to colleagues who design the detector solenoids
for LDC, GLD and SiD. 

In the 2005 field maps the solenoid field tail at 10m from IP is large, 
it reach 1 kilogauss for LDC (for SiD and GLD somewhat smaller). 

If this field is real, there are consequences for beam optics, safety, 
and it also could mean that detector iron is saturated too much, 
as discussed in the attached file. 

Hopefully, this field is not real, and is due to computational error, simply because 
the region outside the detector was not considered important and people 
did not pay attention.   If so, we ask you to update the field maps, 
also providing an estimation for inaccuracy of the calculated field. 

 Best regards, 
  Andrei Seryi for WG4

Attachment: field_tail_question.ppt
Description: field_tail_question.ppt

Attachment: field_tail_question.pdf
Description: field_tail_question.pdf