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SuperB Flavor Factory. ITEP Meeting on the future of heavy flavour physics July 24-25,2006 Marcello A. Giorgi Università di Pisa and INFN Pisa. Outline. So far… Status of SuperB activity Status of Machine Effort. SuperB International Study Group.
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SuperB Flavor Factory ITEP Meeting on the future of heavy flavour physics July 24-25,2006 Marcello A. GiorgiUniversità di Pisa and INFN Pisa Marcello A Giorgi
Outline • So far… • Status of SuperB activity • Status of Machine Effort Marcello A Giorgi
SuperB International Study Group THE GROUP IS OPEN TO CONTRIBUTORS AND PARTICIPANTS !! Goals of SuperB International Study Group : • Study the physics case, machine and detector for a Super Flavor Factory with a luminosity higher than 1036, to study physics in b, c and t sectors. • Prepare by the beginning of 2007 a Report “CDR” to be delivered to the President of INFN , it will be submitted to an International Review Committee and presented to the International Community. Events: 3 Workshops: LNF (November 2005 and March 2006), SLAC (June 2006) UK meeting on SuperB in Daresbury 26-26 April Round table in Elba on Future Machines 23 May : • presentation of Suzuki containing SuperKEKB possibilty (4 1035 and 40-50 ab-1 by 2020) • INFN President R.Petronzio presented SuperB as one of priorities of INFN Marcello A Giorgi
On physics case On the physics case many documents are available they are the result of three years of Physics workshops in Slac ,in KEK and Joint meetings in Hawaii . Three years of Physics Workshops have produced heavy documents . See for example: The Discovery Potential of a Super B Factory (Slac-R-709) Letter of Intent for KEK Super B Factory ( KEK Report 2004-4 ) Physics at Super B Factory ( hep-ex/0406071 ) At the URL : www.pi.infn.it/SuperB you can find documents and links to documents Marcello A Giorgi
On physics case The physics case for a Super Flavour Factory is solid if : See • The sample of data available in a few years of running would be bigger than 50 ab -1 and approaching 100 ab -1 (10 11 B Bbar, tau and charm pairs) . • The running period is overlapped to LHC. (Results from Super Flavour Factory and LHC are largely complementary). Marcello A Giorgi
On physics case.. This issue has been widely presented and discussed in Topical Conferences (as DIF06 in Frascati, 28/2/2006-3/3/2006) and in workshops as the CERN series Flavour Physics in the era of LHC (So far 3 workshops : Nov 2006, Feb 2006 and May 2006) The May workshop included a special session devoted to High intensity, High luminosity flavour experiments and a round table chaired by I.Bigi to compare expected performance and physics expectation from SuperB, SuperKEKB and LHCb . . Marcello A Giorgi
On physics case The physics case is continuing to be refined with the solid contribution of theorists. An ad-hoc subgroup was set up to study the physics reach on t and charm and the possible impact on the machine and detector design of the possibility of one polarized beam and special runs at low cms Energies ( 4.0 and 5.0 GeV) still with a luminosity higher than 10 35cm-2 s -1. Contiguous to the 4th SuperB workshop to be held Nov 16-18 2006 in Rome, a theory meeting is also planned for an updated physics assessment. On this subject today I will only show few vignettes Marcello A Giorgi
UNIVERSAL UT fit with 50 ab-1 Universal fit makes only use of quantities independent of NP contributions within MFV Marcello A Giorgi
bsl+l- precision measurements Marcello A Giorgi
Extrapolation at high Lumi Marcello A Giorgi
Rare Decays Marcello A Giorgi
Report on SuperB Accelerator Effort SuperB Contributors (Accelerator): BINP: Koop,Levichev, Shatilov KEKB: Ohmi LNF: Biagini, Raimondi,Zobov Pisa: M.G., Paoloni SLAC: Novokhatski, Seeman, Seryi, Sullivan, Wienands Marcello A Giorgi
A Comment! SuperB is commonly named “Linearly colliding Super B Factory” to avoid confusion and misinterpretation: SuperB is not a linear collider. It is instead a machine that is based on several concepts of linear collider as: Damping rings to get very low emittance, the final focus as in linear collider and in general the characteristics of very small size of the bunches for the high luminosity. Marcello A Giorgi
SuperB effort • Strong interest of SLAC PEP-II staff to collaborate and possibly contribute with hardware (PEP-II magnets, vacuum pumps, power supplies, RF) • Interest from other major Laboratories (SLAC,KEK, BINP) to collaborate on proof-of-principle simulations • Before the IV SuperB Workshop in Rome (16-18 November 2006) there will be at the end of september 2006 an “Accelerator only” retreat week . Marcello A Giorgi
Summary from Oide’s talk at 2005 2nd Hawaii SuperBF Workshop • Present design of SuperKEKB hits fundamental limits in the beam-beam effect and the bunch length (HOM & CSR) • Higher current is the only way to increase the luminosity • Many technical and cost issues are expected with a new RF system • We need a completely different collider scheme..... Marcello A Giorgi
Issues • HIGH CURRENT and HIGH BACKGROUND IS AN ISSUE FOR : • DETECTOR DESIGN • WALL POWER NEEDED Marcello A Giorgi
Simplified SuperB layout Crossing angle = 2*25 mrad ILC rings & ILC FF Marcello A Giorgi
Machine parameters • Present parameter set based on ILCDR-like parameters: • Same DR emittances • Same DR bunch length • 1.5 times DR bunch charges • PEP-KEK DR damping time • Same ILC-IP betas • Crossing angle and “crab waist” to minimize bb blowup Marcello A Giorgi
REQUIREMENTS High luminosity requires: - short bunches - small vertical emittance - large horizontal size and emittance to mimimize beam-beam For a ring: • easy to achieve small horizontal emittance and horizontal size • Hard to make short bunches Crossing angle swaps X with Z, so the high luminosity requirements are naturally met: Luminosity goes with 1/ex and is weakly dependent by sz Marcello A Giorgi
Crossing angle concepts sx sz Overlapping region sz sx Overlapping region Both cases have the same luminosity, but (2) has longer bunch and smaller sx With large crossing angle X and Z quantities are swapped: Very important!!! 1) Standard short bunches 2) Crossing angle Marcello A Giorgi
x bY e- e+ 2sx/q 2sz*q q z 2sz 2sx “Crab waist” (P. Raimondi) Vertical waist has to be a function of x: Z=0 for particles at –sx(- sx/2q at low current) Z= sx/q for particles at +sx(sx/2q at low current) Crabbed waist realized with a sextupole in phase with the IP in X and at p/2 in Y “Crab waist” removes beam-beam betratron coupling Introduced by the crossing angle Marcello A Giorgi
Crab waist properties • Large Piwinski's (not only crossing) angle: QP=q*sz/sx • Low by comparable with the 'overlap area' • Low bx and long bunch length • Crab focus eliminates the betatron resonances introduced by the Piwinski's angle • Synchrotron resonances are not suppressed but damped horizontally • Partial compensation of the hourglass effect due to the by shift along the 'overlap' area. by is shifted not only with x, but also along the longitudinal axis For a fixed longitudinal position, by does not depend on the horizontal motion anymore ! No vertical modulation due to the horizontal oscillations ! Marcello A Giorgi
Crab-waist simulations • The new idea is being checked by several beam-beam codes: • Guinea-Pig: strong-strong , ILC centered • BBC (Hirata): weak-strong • Lifetrack (Shatilov): weak-strong with tails growths calculation • Ohmi: weak-strong (strong-strong to be modified for long bunches and large angles) Storage rings Marcello A Giorgi
BB simulations with ILC code Horizontal Plane Vertical Plane Collisions with uncompressed beams Crossing angle = 2*25 mrad Relative Emittance growth per collision: eyout/eyin=1. 5x10-3 Marcello A Giorgi
Ohmi’s weak-strong code Luminosity Vertical blow-up K2 is the strength of the sextupolar nonlinearity introduced to have crab waist Marcello A Giorgi
Conclusions on bb simulations • The “crossing angle with crab waist”scheme has shown big potentiality and exciting results LNF, Pisa, BINP and KEKB physicists are working on bb simulations with different codes to find the best set of parameters • This scheme is promising also for increasing luminosity at existing factories, asDAFNE, KEKBand possiblyPEP-II • Crab waist scheme is planned to be tested in 2007 in DAFNE Marcello A Giorgi
SuperB ILC-like rings • ILC OCS (Baseline) lattice used • Scaled to 4 and 7 GeV • 3.0Km long rings studied • Lattice symmetry respected • Fewer and lower field wigglers used (pm ) • Preliminary Final Focus (ILC-like) included • Design based on recycling all PEP hardware, Bends, Quads and Sexts, and RF system • Maximize Luminosity keeping low DE and wall power. Marcello A Giorgi
Possible site: Tor Vergata campusRing circumference: 3. to 2.2 Km O 0.7Km O 1.0Km Marcello A Giorgi
Ring Parameters Marcello A Giorgi
Upgradeable 1036 M. Zobov, D. Shatilov Marcello A Giorgi
EXERCISE 1 :4x7 GeV rings with PEP-II dipoles & quadrupolesin a 3.0Km ring Marcello A Giorgi
SuperB-ILC synergy • Potential size and cost reduction of the ILC complex • Potential decrease of the ILC commissioning time • Potential increase of the ILC performances • Could the ILC community benefit by having an operating positron DR just 3 Km long delivering 4741 bunches with 3x1010 particles/bunch? • Could the ILC community benefit by having an operating Beam Delivery System with ILC-IP beams sizes and betas? Marcello A Giorgi
Conclusions on machine • Solution with ILC DR + ILC FF seems extremely promising • Uses all the work done for ILC (DR and FF) 100% synergy with ILC • Beam Currents around 3.0/1.7 A, and backgrounds should be better than PEP and KEKB • Possibly to operate at the t energy with L=1035 • Needs the standard injector system, probably a C-band 7GeV linac like in KEKB upgrade • Possibility to simultaneously boost the performances of the existing machines and do SuperB R&D. Marcello A Giorgi
Beam Pipe Radius and Detector Issues 7+4GeV Boost bg=.28 Instead of 0.56 • Small beam pipe radius possible because of small beam size • Studied impact of boost on vertex separation (Bpp) • Rest of tracking is Babar • Beam pipe needs to be cooled.Study is in progress to keep total thickness low in the order of % of rad Separationsignificance Proper timedifferenceresolution Marcello A Giorgi
Pipe Inner Radius 1 cm “Uniform” water gap (8 flat channels) Single channel area = 2.35 mm2 Channel width = 300 mm To dissipate 1KW with water specific heat and thermal conductivity Possibly a Peek (plastic) jacket Requires channel 1-side coating to prevent erosion (7mm Ni or BerylcoatD) Flow: 4.2 m/s (OK) Marcello A Giorgi
Detector comments Background should be lower than in Babar. Occupancy would be OK in Vertex Detector even with a smaller radius beam pipe. (from 3cm of Babar down to 1.cm). Simulations are currently run for interaction region and Bgkd. Apparatus would be more hermetic than Babar and Belle (7+4 GeV). Detectors don’t require a major R&D PID would be needed also in forward/backward direction. By reducing Lorentz boost higher resolution vertex is needed (MAPS?) R&D on EMC (Babar Caltech..) R&D on PID (Babar: Slac) (Belle :KeK ,Lubijana x5 scale with 10mm radius BP, 6mm pixel chip • R&D on Maps within Belle (Hawaii group)and Babar (Pisa+Slac) • Two monolithic active pixel layers glued on beam pipe • Since active region is only ~10mm, silicon can be thinned down to ~50mm.Good resolution O(5mm). • Improves pattern recognition robustness and safety against background Marcello A Giorgi
MAPS R&D Charge sharing =105 mV =12 mV threshold 55Fe X-rays Noise only (no source) PRE SHAPER DISC LATCH Landau peak 80 mV 90Sr electrons threshold saturation due to low energy particle. 1250 2200 3000(e-) 1640 ST 0.13um triple well technology Single pixels tested with source Full signal processing chain • SLIM chip (Babar collabor.) Marcello A Giorgi
FINAL Conclusion Either BaBar or Belle can be reused in SuperB with a moderate upgrade. Trigger and DAQ must be updated. Marcello A Giorgi
BACKUP Marcello A Giorgi
SuperB-Factories Parameters before SuperB activity(may05) Marcello A Giorgi
SuperKEKB (K. Ohmi) Marcello A Giorgi
Hybrid Cooling Chamber Outer peek wall + Be wall = Flange detail O-ring insertion F.Raffaelli Marcello A Giorgi
Power dissipation 1 KW T Inlet 8 C T MAX raise 3 C Water speed < 5m/s Negative pressure Gold foil 4 um 0.121 % X0 Berillium 300 um 0.142 % X0 Peek layer 500 um 0.330 % X0 Water 300 um 0.083 % X0 Ni coating 7 um 0.050 % X0 Total 0.726 % X0 Marcello A Giorgi
EXERCISE 2 : 7 GeV ring, 2.2 Km as PEPII Marcello A Giorgi
Nominal damping 2.5 times longer 5 times longer N = 2.5 x 1010 Ax x Ay = 15 sx x 20 sy N = 5.0 x 1010 Ax x Ay = 25 sx x 80 sy Marcello A Giorgi
SuperSuperB with ILC Damping Ring Parameters Working Point (0.53,0.57); Nb = 7.5 x1010; 6000 Bunches 0.6/q 0.8/q 1.0/q L = 1.22 x 1037 cm-2 s-1 D.N.Shatilov, M.Zobov Marcello A Giorgi
Detector Issues As the present parameters for 1036 machine show a running condition not substantially different from the present PEPII/BaBar. One of the present detectors running at BFactories (BaBar or Belle) could be used as is without major modifications (Trigger,DaQ…). However, mainly due to the reduced asymmetry (7x4 GeV) in the present parameter choice of SuperB a new beam pipe with a small radius and an improved SVT are needed. An improvement in Detector acceptance and in PID performance are welcome . Detector Effort under coordination of F.Forti and A. Roodman, is currently carried mainly from Caltech,Pisa and Slac. Marcello A Giorgi