Part of discussion led by Part of discussion led by Oliver Bruning, CERN Oliver Bruning, CERN Vladimir Shiltsev, LARP/Fermilab Vladimir Shiltsev, LARP/Fermilab Soft Ranking of Soft Ranking of LHC Upgrade Possibilities LHC Upgrade Possibilities
Feb 01, 2016
Part of discussion led by Part of discussion led by
Oliver Bruning, CERNOliver Bruning, CERN
Vladimir Shiltsev, LARP/FermilabVladimir Shiltsev, LARP/Fermilab
Soft Ranking of Soft Ranking of LHC Upgrade PossibilitiesLHC Upgrade Possibilities
LHC Upgrades – O.Bruning, V.Shiltsev 2
Factors to be considered Factors to be considered Whether technology available Whether technology available
if not – when Cost of the Upgrade Cost of the Upgrade
<few MEU,<few 10s M,<few 100sM Time to construct & installTime to construct & install Luminosity gain Luminosity gain Physics risk to not get the gain Physics risk to not get the gain
e.g. energy deposition, BB, optics
LHC Upgrades – O.Bruning, V.Shiltsev 3
LHC Upgrades – O.Bruning, V.Shiltsev 4
Thus:Thus: Group A (definetely Group A (definetely
explore)explore) all collimator projects both quad first paths b-b compensation schemes: W, EL
Group B (carefully look into)Short bunch and 12.5-75 nsDipole firstCrab crossing
LHC Upgrades – O.Bruning, V.Shiltsev 5
““Worth the buck?”:Worth the buck?”: Tev(RHIC?) rule of thumb:Tev(RHIC?) rule of thumb: 1M$ upgrade 1M$ upgrade 2-4% in Lumi 2-4% in Lumi Group A Group A
feedback b-b compensation schemes: W, EL new collimation schemes both quad first paths new 12.5-75ns schemes
Group B (carefully look into)Short bunchAll IR upgrades
LHC Upgrades – O.Bruning, V.Shiltsev 6
Manager’s ViewManager’s ViewDepends on “Manager’s Depends on “Manager’s Model” Model”
assume intelligent assume intelligent manager:manager:
Paranoic – minimize the risk Paranoic – minimize the risk Assure SOME improvementAssure SOME improvement Start long lead projects Start long lead projects
ASAPASAP
LHC Upgrades – O.Bruning, V.Shiltsev 7
LHC Upgrades – O.Bruning, V.Shiltsev 8
Thus:Thus: Group A (DO NOW)Group A (DO NOW)
both quad first paths Magnet R&D… Magnet R&D…Magnet R&D
Group B (support now , be prepared to do later) feedback collimator schemes (RC, LEL, Crystals) beam-beam compensation schemes
Group C (make sure assumptions/ estimates right, before rule out): dipole first short bunches crab crossing
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Possible Action Items (I)Possible Action Items (I) MAGNETS – all has been said
already
MARS and Fluka has to agree (resolve ~2 difference)
LHC Upgrades – O.Bruning, V.Shiltsev 10
Possible Action Items (II)Possible Action Items (II) On a way to decision in ~1 yr:
Riccardo to wrap up dipole first analysis•Work with Tanaji (visit FNAL for ~mos)
and Ramesh (a week at BNL)Rama to finish crab cavity analysis
•Given Ohmi’s error – reconsider tolerances
•Learn from KEK experience•Generate the most attractive proposal
Short bunches so attractive •Make one more inventive/critical look
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Possible Action Items (III)Possible Action Items (III) Deeper collaborative look into items
promising a lot of return for small investment: collaboration important as CERN
people to be busy with commissioning while “helpers” don’t “feel” the machine well
beam demonstrations most convincing allow to attract and keep younger
scientists interested Therefore:
Expand beam-beam simulations collaboration on LEL (Ulrich, VS, FZ)
LHC Upgrades – O.Bruning, V.Shiltsev 12
Cont’dCont’d
simulate LEL hollow collimator (Rogelio, , FZ, VS)
look into low-noise FB tolerances (??) crystal collimation design
considerations (Walter+LARPies) full support of BBLR MDs at RHIC and
rotating collimators (LARPies) very low beta* solutions very
sesnsitive to vibrations, need to look into tolerances and research vibration levels, including beam screen jitter(Riccardo, Vladimir)