Dear Colleagues, I am announcing that CCB has received a change request for the Beam Delivery System (BDS) section of ILC Baseline Config Doc from A.Seryi, who is co-representing the BDS AG with D.Angal-Kalinin and H.Yamamoto. This change request relates to an attempt at clarifying the assembly procedure for ILC detectors. The present BDS BCD does not explicitly specify the method of underground assembly; however it has been implicitly assumed in the BCD that detectors are assembled underground. This change request is to specify in BCD that assembly of detector will be done on-surface, in a manner similar as was done for CMS detector at CERN. According to the requesters, this is expected to reduce the construction time of the IR-related portion of ILC since the detector subassembly work does not have to wait for completion of the underground hall, and is also expected to reduce the construction cost. The requesters suggest Class 1 as classification for this change request. The CCB chair tentatively agrees to treat this as Class 1, pending analysis of the associated cost-delta and impacts. I am assigning T.Markiewicz and G.Blair (to be confirmed), plus myself, to act as CCB co-reviewers. Although some statements have been already offered by groups outside BDS (e.g. MDI) I will be requesting remarks, comments and assessments, if any, from - Cost engineers - CF/S GG leaders - Installation GG leaders - MDI in separate emails. Now this request is brought to review by CCB, and is also open to general discussion. Any members of GDE or GDE-related task groups with comments or questions on this request, please, direct them to ml-ccb@xxxxxxxxxxxx and/or ml-ext-gde@xxxxxxxxxxxx by the end of Wednesday Sep. 27, PDT. Details of this change request is available as http://www-project.slac.stanford.edu/ilc/acceldev/beamdelivery/rdr/docs/CCR_surface/CCR_surface_assembly.doc BCD is available at http://www.linearcollider.org/wiki/doku.php?id=bcd:bcd_home BCD change history is available at http://www.linearcollider.org/wiki/doku.php?id=bcd:bcd_history RDR-related information repository for BDS is found at http://www-project.slac.stanford.edu/ilc/acceldev/beamdelivery/rdr/ Sincerely,
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- Subject: [CCB-680] change request from BDS (on-surface detector assembly)
- From: "Seryi, Andrei" <seryi@xxxxxxxxxxxxxxxxx>
- Date: Wed, 20 Sep 2006 21:28:58 -0700
Dear Nobu and Colleagues in CCB, We are submitting a change request which is described in the attached file "CCR_surface_assembly.doc". The supporting files are linked from "CCR_surface_assembly.doc" and are placed here http://www-project.slac.stanford.edu/ilc/acceldev/beamdelivery/rdr/docs/CCR_surface/ Best regards, BDS Area leaders Deepa Angal-Kalinin, Andrei Seryi, Hitoshi YamamotoAttachment: CCR_surface_assembly.doc
Description: CCR_surface_assembly.doc
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