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Physics @ Super- t -c factory. Some starting points for discussion. Generalities. Production cross-sect., lumin.: cc prod. cross-sect. at U (4S): ~1.3 nb; prod. of D* + → D 0 p + : 4x10 7 D 0 ’s/100 fb -1 ; prod. of D 0 ’s at y (3770): 6x10 7 D 0 ’s/100 fb -1 ;
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Physics @ Super-t-c factory Some starting points for discussion
Generalities Production cross-sect., lumin.: cc prod. cross-sect. at U(4S): ~1.3 nb; prod. of D*+→ D0p+: 4x107 D0’s/100 fb-1; prod. of D0’s at y(3770): 6x107 D0’s/100 fb-1; Super-B: ~8-10 ab-1/year (107 s); Super-t-c: ~1 ab-1/year; BES-III: ~10 fb-1/year; Time schedule? end of 2011: BES-III 30 fb-1 Super-Belle start in ~10 years(?): Super-B Super-t-c
List of possible topics Questions: - motivation answers: high/medium/low - what precission is needed/can be achieved (compared to Super-B/BES-III/LHCb) answers: feasible/not feasible/not useful
List of possible topics Physics topics - t
List of possible topics Physics topics - t
List of possible topics • Physics topics - charm • leptonic decays (decay constants) • semileptonic decays (form factors) • rare decays (NP search/identification) • D0 mixing, CPV • t-dependent/t-independent • CPV, so far unused methods at • B-factories • (T-odd observables, advantages of • polariz. - LcLc) • Spectroscopy • “exotic” (X,Y,Z); X(3872) 1++ (B decays) ; • Y family 1--(ISR produced from U(4S)); • Z+(4430) (B decays); • production, CMS energy, scan? • s(D(*)D(*)) @ s~4.5 GeV • (inclusive/exclusive) Other (gg, ...)
List of possible topics • Machine & detector topics • need for asymmetric energy machine? • (asymmetry factor?) • CMS energy, scan? • Long. polarization - energy interval? • Transverse polariz.? • Need for equal polariz. of opposite helicity? • Need for polarized e+ beam? • p/m , p/K, p/e PID performance needed? • Vertex detector? • Beam pipe issues? • Momentum resol.? • EM calorim. angular & energy resol.? • KL, m range system? • polarization measurement? • Hermeticity? • MC (background) simulation
1. Ds leptonic decays Ds→mn Average of absolute meas.; huge improvement in LQCD accuracy; to do list: confirm LQCD uncertainty; reduce exp. uncertainty; Ds→t(enn)n 0.4% non-scaling syst. (#tags) BES-III: s(fDs)~1%; from t(enn)nalone with 100 fb-1s(fDs)~0.5% (not considering more tagging modes) Belle, PRL100, 241801 (2008), 548fb-1 Cleo-c, PRL99, 071802 (2007), 314pb-1 m, t (pn) Cleo-c, PRL100, 161801 (2008), 298pb-1 t (enn) aver. 274 ±10 MeV MILC, PRL95, 122002 (2005) LQCD 241 ±3 MeV HPQCD, UKQCD, PRL100, 062002 (2008) 3.3 s discrepancy 230 240 250 260 270 280 290 300 MeV Cleo-c, PRL100, 161801 (2008), 298pb-1
2. Semileptonic decays Vub exclusive measurements, B → pln |Vub|f+(0) |Vub|=(3.6 ± 0.5)x10-3 comparable accuracy to incl. measurements f+(0) th. uncertainty (LQCD) ±12% need: improvement in th. accuracy & tests of LQCD f.f. calculations in charm sector D →Pen, P=K, p; untagged meas., pn from pmiss; q2 dependence (s(q2)~0.01 GeV2); sys. due to n simulation ±1.7% on Br; total error ±4.8% on Br; with 1 ab-1 uncertainty on |Vcd|f+D(0) dominated by syst. error, ~ 0.5%; D0→pen Cleo-c, PRD77, 112005 (2008) 281 pb-1
W± d,s,b Z0,g c u ~ ~ c u ~ Z0,g g c u l+ l- u, d u, d 3. Rare decays D±→p±l+l- need sensitivity to ~10% of Br at high/low mee; w f mee[GeV] e~40%, Br(mee<0.7 GeV)~10-7, background? (negligible in ) Cleo-c, PRL95, 221802 (2005) 281 pb-1
4. D0 mixing D →K*(p1,e1)K*(p2,e2) T(pi,ei) = -pi,ei; but AT ~ sin(f+d) f: weak phase d: strong phase; asymmetry of conjugated process ATCP~ sinfcosd n.b.: ACPdir ~ sinfsind
4. D0 mixing CPV Lc →Lp p L rest frame L Lc p q p angular distrib. diff. between Lcand anti-Lc; s(e+e-→Lc X) at U(4S) ~ 0.2 nb at threshold ~0.5 nb
5. Spectroscopy X(3872) JPC=1++, 2-+; DD* mode larger than J/ypp 1++ favoured; not easy to produce; y(4040), y(4160) decays? Y family Y(4260), Y(4360), Y(4660); produced in ISR from U(4S), 1--; @4.2 GeV eff. lumin. ~O(100 pb-1) hybrid, DD1(D*p) decay mode? hc” cc1’ y2 y3 MD+MD* hc’ hc2 y” y’ hc’ cc2 hc cc1 cc0 J/y hc
Super-KEKB bckup KEK roadmap A. Suzuki, KEK Director General, Inaugural meeting of Super Belle
Ds leptonic decays bckup Ds→mn Average of absolute meas.; huge improvement in LQCD accuracy; agreement for fD+: LQCD: 208 ± 4 MeV exp.: 223 ±17 MeV (but exp. error larger than for fDs) Belle, PRL100, 241801 (2008), 548fb-1 Cleo-c, PRL99, 071802 (2007), 314pb-1 m, t (pn) Cleo-c, PRL100, 161801 (2008), 298pb-1 t (enn) aver. 274 ±10 MeV MILC, PRL95, 122002 (2005) LQCD 241 ±3 MeV HPQCD, UKQCD, PRL100, 062002 (2008) 230 240 250 260 270 280 290 300 MeV 3.3 s discrepancy to do list: confirm LQCD uncertainty; reduce exp. uncertainty;
Cleo-c, PRL99, 071802 (2007), 314pb-1 Ds leptonic decays bckup Ds→mn, t(pn)n signal shape checked with fully recon. events (with one Ds discarded); 5% syst. on Br from #tags; out of this ~3% from unknown bkg. shape & bias in #tags in mn, pnn compared to generic events 1.5% non-scaling system. on fDs; total 5.4% error on fDs; tags Ds→KKp, MM*2 from Dstag, g Cleo-c, hep-ex/0607074, 200pb-1
Cleo-c, PRL100, 161801 (2008), 298pb-1 Ds leptonic decays bckup Ds→t(enn)n sideband subtraction for #tags; syst. on Br from #tags 0.8%; peaking bkg. from KLen; estimated from data using KSen; 0.4% non-scaling system. on fDs; total 6.6% error on fDs; BES-III: s(fDs)~1% from t(enn)nalone with 100 fb-1s(fDs)~0.5% (not considering more tagging modes) tags energy in calorim. from Ds*Ds (signal g from Ds*)
Ds leptonic decays bckup Ds→ln NP B.A. Dobrescu, A.S. Kronfeld,, PRL100, 241802 (2008) M: NP mass type II two Higgs doublets models: destructive interference
Semileptonic decays bckup Vub exclusive measurements, B → pln |Vub|f+(0) |Vub|=(3.6 ± 0.5)x10-3 comparable accuracy to incl. measurements f+(0) th. uncertainty (LQCD) ±12% need: improvement in th. accuracy & tests of LQCD f.f. calculations in charm sector D →Pen, P=K, p; untagged meas., pn from pmiss; q2 dependence (s(q2)~0.01 GeV2); shape of f.f. determined in data; D0→pen Cleo-c, PRD77, 112005 (2008) 281 pb-1
Semileptonic decays bckup Vub absolute measurement of Br, need N(DD); sys. error due to N(DD) scales with lumin.; sys. due to n simulation ±1.7% on Br; total error ±4.8% on Br; Br(D0→pen)=(0.299±0.011±0.009)% with 1 ab-1 uncertainty on |Vcd|f+D(0) dominated by syst. error, ~ 0.5%; method of absolute Br measurement developed also by Belle; with 5 ab-1 uncertainty on |Vcd|f+D(0) ~1% D. Asner, ICHEP’08 Cleo-c, PRD77, 112005 (2008) 281 pb-1
W± d,s,b Z0,g c u ~ ~ c u ~ Z0,g g c u l+ l- u, d u, d Rare decays bckup D±→p±l+l- need sensitivity to ~10% of Br at high/low mee; w f mee[GeV] 90% C.L. UL on total Br ~ 7.4x10-6 for e+e- mode, excluding resonant contrib. Cleo-c, PRL95, 221802 (2005) 281 pb-1
Rare decays bckup D±→p±l+l- e~40%, Br(mee>1.1 GeV)~10-7, background? (negligible in ) Cleo-c, PRL95, 221802 (2005) 281 pb-1