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b ...but you will only get a On Fri, 16 Jun 2017, Marcel Stanitzki wrote: > Dear all > > As you may have heard, there are many discussions now ongoing on to start > with > an ILC at 250 GeV to lower the initial cost of the project. > There seems to be quite some support for this scenario from Japanese > Government circles. > > There are four distinct scenarios one could think about which involve both > machine and tunnel options > > a) 250 GeV machine in a 250 GeV tunnel > Only build a tunnel suitable for 250 GeV machine, later updates will > require major construction work > > b) 250 GeV machine in a 500 GeV tunnel > Only build a 250 GeV machine but drill the complete 31 km tunnel for 500 > GeV, later updates will only require installation of > Cryomodules, RF, etc. and can be adiabatic > > > c) 250 GeV machine in a 350 GeV tunnel > Only build a 250 GeV machine but drill a tunnel suitable for 350 GeV > machine > With a 10% increase in cavity gradient, this can later be still enough to > get to 500 GeV. The cost increase for the 350 GeV tunnel will be a few % > > d) 500 GeV or bust > We need to start at 500 GeV, so go for the complete project as spec'ed in > the TDR > > One should also point out, that the 250 GeV machine is not half-price, it is > very roughly more like two-thirds of the 500 GeV machine, but detailed > costing studies will be presented at the SLAC workshop > Since this is really affecting the physics program and the associated > timescales, we'd like to hear your input. > > Which option would you prefer, keeping the signals from Japan in mind ? > > Best wishes > > Andy & Marcel > > -- > Marcel Stanitzki > DESY/ATLAS > Notkestraße 85, 22607 Hamburg > Geb. : 1c/O1.338 > Tel. : +49 40 8998 4930 > Cell : +49 40 8998 9 4930 > > ######################################################################## > Use REPLY-ALL to reply to list > > To unsubscribe from the SID-ALL list, click the following link: > https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=SID-ALL&A=1 > ######################################################################## Use REPLY-ALL to reply to list To unsubscribe from the SID-ALL list, click the following link: https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=SID-ALL&A=1