WW reported on the EVM status. All
data for the Tasks and Workunits, with the exception of BT-EC, have been
implemented and crosschecked with APT. The total budget adds up to
10,104.000 CHF and 34.05 FTE, BT-EC budget included but FTE still to be
added. WW will contact the project management to enquire how and when the
data needs to uploaded.
BG presented the
BI.BS fall
time requirements. The Bi line was checked with matched (-1.382
m) and mismatched (0 m) dispersion Dx, and the results clearly
indicate that a mismatched Dx is preferred due to an decreased
number of foil hits per p+. Furthermore, the proton density on
the foil in case of a mismatched Dx is independent of the fall
time constant. BG will contact the LINAC4 optics team to check whether a
mismatched Dx in this part of the line is feasible. TF commented
that an increased fall time, compared to the 40 μs design value, will result
in considerable design simplifications and positive impact on the cost of
the pulse generators. JB proposed to investigate if a BI.BS magnet design
with increase lamination thickness(~0.35mm) is feasible, which also has
positive influence on the vacuum requirements, and check the influence on
the pulse fall times.
MH gave a status report of the BI.DIS,
indicating that the final set of drawings of the magnet, coil and ferrite
yoke has been completed. The status of the drawings for the vacuum tank is
~90%. The High Voltage feed-through will be based on an existing, slightly
modified, design. The cost per feed-through is in the order of 2000 GBP
each. It is proposed that the coils will be welded by laser using an special
designed, but expensive, tooling. Nevertheless, due to the requirements of
10 coils this will have the advantage of high precision at an acceptable
price.
WW mentioned that in the L4/PSB commissioning WG of 10 April the aperture limitations of transfer line and PSB injection will be discussed. Following this meeting it needs to be clear what apertures for BT equipment will be acceptable since manufacture of the BI.DIS components will start soon.