KEK news (2020.3.2) S.Tanaka

BELLE PAC 2/19-20 @KEK http://kds.kek.jp/conferenceOtherViews.py?view=standard&confId=4483 Report from KEKB Accelerator Review Recommendation: The KEKB Group should create a Parameter Team to develop and approve a consistent parameter set for SuperKEKB The team should have participation from each group to ensure a fully integrated design for the machine During the last year, each group has worked semi-independently to look for showstoppers All of this work now needs to coalesce The KEKB and BELLE Groups should formally create a joint working group to optimize the interaction region and the machine-detector interface The first topic to be decided is the rotation of the BELLE detector The second topic to be studied is how to understand and minimize the detector background In addition, a solution should be developed for damping vibrations of the interaction region components and/or the beam to maintain luminosity (Review Committee Report draft is uploaded on wiki page :KEK contact )

PXD Reviewer’s comment BG simulation including kinematic supports should be done (it may cause serious BG for SVD). The estimation of occupancy should make clear by performing simulation. BG effect: charged particle , photon, neutron PXD DAQ issues should be solve by discussing with DAQ group, sufficiently. PAC review member will be reviewing BELLEII TDR next May.

IR Beam ducts in the cryostat are water cooled. The central part of the present IP chamber is free from direct synchrotron radiation from the last bend. ( in the 0th approximation). Design and test of the IR assembly (should be done by 2011 Oct.) IR meeting will be merged into one.

SuperKEKB Main Ring schedule K. Akai SuperKEKB Main Ring schedule FY2009 FY2010 FY2011 FY2012 FY2013 FY2014 Beam operation MR commissioning Tunnel clear Remove magnets and beam pipes Base plates Beam pipes (LER_wiggler) Fabrication TiN coating Install Beam pipes (LER_arc) Design Fabrication TiN coating Beam pipes (HER_arc) Install Design Fabrication Install Magnets & Power supplies Design / Fabrication Field measurement Install Cabling / Check Alignment 2nd? Beam monitors and Control R&D / Fabrication Test RF reinforcement Layout change / Add stations / Cavity improvements IR hardware Conditioning QCS R&D QCS fabrication Install & test

Radiation hardness :DAQ hardware Radiation hardness of front-end electronics - Many FPGAs are used in detector FEE placed inside detector structure. - There is some worry about the radiation hardness. -> Radiation test during KEKB operation Exposed FPGA+optical link (Virtex2Pro+Rocket IO) in beam line during 2009 runs and studied the error rate in the data transfer. Result: * Only 1 error during spring run ( ~11kRad) * ~10 errors during fall run (~64kRad), and then went dead.

DAQ

Next B2GM PXD session will be divided into 1,Mechanics, service meeting (IR,PXD,SVD,CDC :concerned person) 2, PXD main session (all detector parts agreed with this plan) Other private meeting? ( BG simulation, DAQ etc.)