Fabiola Gianotti, 14/10/20031  s = 28 TeV upgrade L = upgrade “SLHC = Super-LHC” vs Question : do we want to consider also the energy upgrade option or only the luminosity upgrade ? Easier for machine Challenging and expensive for machine Major changes to detectors for Modest changes to detectors full benefit, very difficult environment Smaller physics potential: Larger physics potential: -- mass reach 20-30% higher than LHC -- mass reach ~1.5 higher than LHC -- precision measurements possible but -- many improved measurements (e.g. Higgs) -- with significant detector upgrades -- higher statistics than LHC -- challenging due to environment -- LHC-like environment Cost : ~ 25% of LHC project ? ??? Maximum exploitation of existing tunnel, machine, detectors …  good physics return for “modest” cost ? More powerful than L upgrade but benefit/cost ratio should be better understood …  wait for LHC data

Fabiola Gianotti, 14/10/20032 Trackers : need to be replaced (radiation, occupancy, response time) -- R > 60 cm : development of present Si strip technology ~ ok < R < 60 cm : development of present Pixel technology ~ ok -- R < 20 cm : fundamental R & D required (materials, concept, etc.) -- channel number ~ 5 larger (occupancy)  R&D needed for low cost Calorimeters : mostly ok (radiation resistance of CMS end-cap ECAL ?) Muon spectrometers : mostly ok -- increase forward shielding  acceptance reduced to |  |< 2 -- space charge effects, aging ? -- some trigger chambers (e.g. ATLAS TGC) too slow for 12.5 ns Electronics and trigger : large part to be replaced -- new LVL1 trigger electronics for 80 MHz -- R&D needed for e.g. tracker electronics (fast, rad hard) -- most calorimeter and muon electronics ~ ok (radiation resistance ?) L = : experimental challenges and detector upgrades If bunch crossing 12.5 ns  LVL1 trigger (BCID) tracker (occupancy) must work at 80 MHz ~ 120 minimum-bias per crossing (compared to ~ 25 at LHC) occupancy in tracker ~ 10 times larger than at LHC (for same granularity and response time) pile-up noise in calorimeters ~ 3 times larger (for same response time) Cost : ~ 300 MCHF (material only) ?

Fabiola Gianotti, 14/10/20033 Summary of reach and comparison of various machines Approximate mass reach of LHC and upgrades:  s = 14 TeV, L=10 34 (LHC) : up to  6.5 TeV  s = 14 TeV, L=10 35 (SLHC) : up to  8 TeV  s = 28 TeV, L=10 34 : up to  10 TeV Only a few examples …. In many cases numbers are just indications …. Units are TeV (except W L W L reach)  Ldt correspond to 1 year of running at nominal luminosity for 1 experiment † indirect reach (from precision measurements) PROCESS LHC SLHC VLHC VLHC LC LC 14 TeV 14 TeV 28 TeV 40 TeV 200 TeV 0.8 TeV 5 TeV 100 fb fb fb fb fb fb fb -1 Squarks W L W L 2  4  4.5  7  18  6  90  Z’ † 30 † Extra-dim (  =2) † † q*  compositeness Most important issues (my view …): -- measurement of Higgs self-coupling and H  -- strong EWSB -- coverage of MSSM Higgs sector vs TESLA-like LC