Heavy Flavors Sheldon Stone Syracuse University The Hadron

Heavy Flavors Sheldon Stone, Syracuse University The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 1

Introduction n “Heavy” flavors, defined as b & c quarks, not t, which is heavier, as the top doesn’t live long enough to form a meson and just decays ~100% directly to b quarks (In England we have “Heavy” flavo urs ) Charm is interesting in several special areas, but I will concentrate on b’s First I will discuss some specific b phenomenology and then point out why these studies are extremely important and interesting The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 2

Some B Meson Decay Diagrams n n n a) is dominant b) is “color suppressed” a) & b) are called “tree” level diagrams The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 3

The Standard Model n Theoretical Background n Physical States in the Standard Model n The gauge bosons: W ±, & Zo and the Higgs Ho Lagrangian for charged current weak decays n Where n The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 4

The CKM Matrix n n Unitary with 9*2 numbers 4 independent parameters Many ways to write down matrix in terms of these parameters The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 5

The Basics: Quark Mixing & the CKM Matrix d s b mass u c t m a s s A, l, r and h are in the Standard Model fundamental constants of nature like G, or a. EM n h multiplies i and is responsible for CP violation n We know l=0. 22 (Vus ), A~0. 8; constraints on r & 6 h Collider Physics Summer Schools, Fermilab August 9 -18, 2006 The Hadron n

The 6 CKM Triangles n c Best measured in Bs decays n b a Area of each = A 2 l 6 h, the Jarlskog Invariant The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 From Unitarity “ds” indicates rows or columns used There are 4 independent phases: b, , c, c (a can be substituted 7

|Vcb | Both Vcb & Vub can be determined using diagram (a) when W -→ -n n Can use either inclusive decays B→X -n, with B~10%or exclusive B→D* -n with B~6% n |Vcb |=(41. 96± 0. 23± 0. 35± 0. 59)x 10 -3 inclusive n n (see Kowalewski ICHEP 2006) n Very well based theoretically (HQET) Note difference is 2. 6 x 10 -3, much larger than quoted theoretical errors! The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 8

|Vub | This is much more difficult because the b→u rate is so much smaller than b→c n Inclusive decays are studied with severe cuts to reduce b→u background n |Vub |=(4. 49± 0. 19± 0. 27)x 10 -3 n For exclusive decays use B→p -n (in principle also r -n) n n Again difference between inclusive & exclusive The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 9

Measurements of B mixing 10 o & BS

o o B -B Mixing n B o can transform to B n The eigenstates of flavor, degenerate in pure QCD mix under the weak interactions. Let QM basis be {|1 >, |2>} {|B o >, |B o >}, then The Hadron Collider Physics Summer Schools, o, like neutral K’s Fermilab August 9 -18, 2006 11

Mixing Measurements Diagonalizing we have m= m B -m B L=2|M 12|, G~0 n R= prob B o / prob B o n First seen by ARGUS n P(B o )= 0. 5 Ge-Gt • [1+cos( mt)] n H n Must “tag” the flavor of the decaying B at t=0 using the other B The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 12

m d Measurements m d average 0. 507± 0. 004 ps -1 n Accuracy better than 1% n The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 13

B d Mixing in the Standard Model n n n Relation between B mixing & CKM elements: F is a known function, h. QCD~0. 8 B B and f B are currently determined only theoretically n in principle, f B can be measured, but its very difficult, need to measure B - -n n Current best hope is Lattice QCD The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 14

B s Mixing in the Standard Model n Measurement of B s mixing provides the ratio of Vtd /Vts which gives the same essential information as B d mixing alone, but with much better control of theory parameters n n |Vtd |2=A 2 l 4[(1 -r)2+h 2] |Vtd |2/ |Vts |2=[(1 -r)2+h 2] Circle in ( r, h) plane centered at (1, 0) To relate constraints on CKM matrix in terms of say r & h need to use theoretical estimates of x=f B s 2 B B s / f B d 2 B B d The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 15

CDF Measurement of m s P(B S B S)=0. 5 X GSe-GSt [1+cos( m St)] n It is useful to analyze A the data as a function of a test frequency w n g(t)=0. 5 GS e-GSt [1+Acos( wt)] n CDF: n n for 95% cl limit 3. 7 s effect D 0 90% cl bounds 21> m. S>17 ps-1 The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 16

Constraint on r - h plane n n Need to use theory value for Using both Vub /Vcb & B mixing See http: //ckmfitter. in 2 p 3. fr/ n In principle, could measure f B |Vub | using B - tn, but difficult: Belle “discovery” was “corrected” & Vub error is significant, so use D The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 17

Leptonic Decays: D(s) +n _ c and q can annihilate, probability is to wave function overlap Diagram: or cs (s) In general for all pseudoscalars: Calculate, or measure if VQq is known The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 18

Measuring Charm at Threshold n DD production at threshold: used by Mark III, and more recently by CLEO-c and BES-II. n n n Unique event properties Only DD not DDx produced Ease of B measurements using "double tags“ BA = # of A/# of D's Beam Constrained Mass The Hadron Collider Physics Summer Schools, CLEO-c K-p+ p+ p 0 Ksp+p+ p- Ksp+p 0 Fermilab August 9 -18, 2006 K-K+ p+ 19

Measurement of f D+ To find signal, look for events consistent with one + track opposite a D - tag with a missing n n Compute n Data have 50 signal events in 281 pb -1 CLEO-c n. Find The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 20

DS+→ +n + t+n, t →p+n n DS+→ +n + t+n, t →p+n Sum contains 100 +n + t+n events for MM 2 <0. 2 Ge. V 2 Also, DS+→t+n, t →e+nn K 0 p+ 100 events Weighted Average: f Ds =280. 1± 11. 6± 6. 0 Me. V, the systematic error is mostly uncorrelated between the measurements n n +tn signal line shape 400 Me. V Thus f Ds /f D+=1. 26± 0. 11± 0. 03 (CLEO-c) The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 21

Comparisons with Theory n CLEO-c data are consistent with most models, more precision needed, for both The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 22

Measurements of CP Violating Angles 23

Formalism of CP Violation n CP Eigenstates : n Because of mixing mass eigenstates are a superposition of a|B o >+b|B o > that obey the Schr ödinger equation See Bigi & Sanda “CP Violation, ” Cambridge The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 24

B o CP Formalism II n For CP not being conserved, instead of B n CP is violated if q/p 1 n Time dependence is given by The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 1 & B 2 25

B o CP Formalism III n n n This leads to the time evolution of flavor amplitudes as m=m H-m L , G GL GH (true for B d , not necessarily for B s ) Probability of a B o decay is given by <B o (t)|B o (t)*> & is pure exponential in the absence of CP violation The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 26

CP violation using CP eigenstates n n CPV requires the interference of two amplitudes. We use the direct decay for one amplitude and mixing for the other one Define n n A=<f|H|B o > |A/A| 1 is evidence of CP violation decay amplitude ( “direct” CPV) in the With mixing included, we have CPV if The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 27

CP V using CP eigenstates II n CP asymmetry n for | q/p | = 1 n When there is only one decay amplitude, l=1 then Time integrated n good luck, maximum is – 0. 5 The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 28

CPV using CP eigenstates III n For B d , h n Now need to add A/A n b 0 r 1 for J/ y K s : The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 29

Ambiguities n n n Suppose we measure sin(2 b) using y. K s , what does that tell us about b? Ans: 4 fold ambiguityb, p/2 -b, p+b, 3 p/2 -b Only reason h>0, is B k >0 from theory, and related theoretical interpretation of e The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 30

B Kinematics at the Y(4 S) (Babar & Belle) Asymmetric e+emachines at Y(4 S) The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 From Abe 31

Fit to t Distributions 0 B _ tag B 0 J/y K S 0 0 B _ tag B 0 tag t resolution, wrong tags 0 tag B _ B 0 tag Asym. = -x. CPsin 2 bsin Dm. Dt The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 32

2006: Ba. Bar + Belle From Hazumi ICHEP 2006 The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 33

b (not sin 2 b) measurements B 0 g. D*+D*-Ks Time-dependent Dalitz analysis (T. Browder, A. Datta et al. 2000) cos 2 b > 0 (94%CL, model-dependent) B 0 g. Dh 0 (h 0 = p 0 etc. ) Time-dependent Dalitz analysis cos 2 b > 0 Belle: 98. 3%CL (hep-ex/0605023, accepted by PRL) Ba. Bar 87% CL (BABAR-CONF 06/017) The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 34

CPV in Charmless B Decays n n n Can have both tree & loop diagrams in p+p- (or Penguin Tree r + r -) The weak phase in the tree graph is . The weak phase in the Penguin is different. Therefore, the Penguin can (and does) mess up CP via mixing in p+p. Penguin is unmasked by evidence of po po The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 35

CPV in B r+rn n First done by Ba. Bar confirmed by Belle Not a CP eigenstate , but final state is almost fully longitudinally polarized n f L =0. 978+0. 024+0. 015 (Ba. Bar ) -0. 013 However, Penguin pollution revealed at 3 s level (Ba. Bar ): n B(roro)=( 1. 2± 0. 4± 0. 3)x 10 -6 n B(r+r-)=(23. 5± 2. 2± 4. 1)x 10 -6 n The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 36

CPV in B r+r- II n Constraints on a n. Add B→rp→p+p-po Dalitz plot analyses suggested by Snyder & Quinn The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 37

Results on a The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 38

: B ± Do K ± decays, Do K s p+p. Can have CPV in B decays Just need two interfering amplitudes n For the B - decay: A(B - Do K -) A B r B ei (d. B- ) n Use modes where the D o is indistinguishable from the D o. Then u se Daltiz plot analysis to find see A. Giri et al. , [hep-ph/0303187] n The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 39

from B Do K -, Do K s p+p - d 2 n L/d 2 sensitivity • Belle first saw a clear difference • Now data show a smaller effect Ba. Bar Fermilab The Hadron Collider Physics Summer Schools, August 9 -18, 2006 40

Poor Constraints on See http: //www. utfit. org/ The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 41

Putting It All Together: Status n n Global fit using all available inputs e. K is from CP violation in K o system The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 42

Reasons for Further B Physics Studies There is New Physics out there: Standard Model is violated by the Baryon Asymmetry of Universe & by Dark Matter I will show that B physics will be crucial towards interpreting New Physics found at the LHC 43

The Enigma of Baryogenesis n n n When the Universe began, the Big Bang, there was an equal amount of matter & antimatter Now we have most matter. How did it happen? Sakharov criteria n n n Baryon (B) number violation Departure from thermal equilibrium C & CP violation The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 44

Sakharov Criteria All Satisfied n n n B is violated in Electroweak theory at high temperature, B-L is conserved (need quantum tunneling, powerfully suppressed at low T) Non-thermal equilibrium is provided by electroweak phase transition C & CP are violated by weak interactions. However the violation is too small! n n n B -n B /n = ~6 x 10 -10, while SM can provide only ~10 -20 Therefore, there must be new physics The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 45

Dark Matter n Discovered by Zwicky in 1933 by measuring rotation curves of galaxies in the Coma cluster • Also gravitational lensing of galaxy clusters • Is dark matter composed of Supersymmetric particles? The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 46

The Hierarchy Problem n n Physics at the Planck scale ~10 19 Ge. V is much larger than at the ~100 -1000 Te. V electroweak scale, requires delicate cancellations between fundamental quantities and quantum corrections. New Physics is needed to solve this problem The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 47

Loop Diagrams Penguins Effects of New Particles on B Decays These decays are suppressed, so New Particles can show enhanced effects 48

MSSM Measurements, from Hinchcliff & Kersting (hep-ph/0003090) n Contributions to B mixing Bs J/yh s CP asymmetry 0. 1 sinf cosf. Asin( mst), ~10 x SM u. Contributions to direct CP violating decay B- f. K- vs B+ f. K+ Asym=(MW/msquark)2 sin(f ), ~0 in SM The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 49

Supersymmetry n n n Supersymmetry contains squarks and sleptons. Squark mass matrixes contain information on SUSY breaking mechanisms &/or GUT scale interactions. Quark flavor changing neutral current processes, e. g. B S or D 0 mixing, are sensitive to the off-diagonal elements of the squark mass matrix. The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 50

Examples CP Violation in BS SUSY GUT & B S Mixing Enhancements to B S + SM B~3. 4 x 10 -9, via SUSY adds Ao, Ho, ho SM Current CDF limits B @ 95% cl BS mixing T. Goto, Y. O. Y. Shimizu, Y. Shindou, and B 0 s + - B 0 d + - <1. 0 x 10 -7 <3. 0 x 10 -8 M. Tanaka, 2003 From Okada ICHEP 2006 The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 51

SO(10) ala’ Chang, Masiero & Murayama hep-ph/0205111 n n n Large mixing between nt and n (from atmospheric n oscillations) can lead to ~ ~ large mixing between b R and s R. This does not violate any known measurements Leads to large CPV in B s mixing, deviations from sin(2 b) in B o f K s and changes in the phase The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 52

New Physics Effects in Some Different Models n Different models give different patterns SLAC WS Proceedings) The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 (2003 53

Possible Size of New Physics Effects n From Hiller hep-ph/0207121 The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 54

b s Transitions (Penguins) In SM t in loop dominates and CP asymmetry should be equal to that in J/y. K s § Other objects in loop, new virtual particles, could interfere § So this process is sensitive to new physics n The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 55

CPV Measurements In b s n n n We cannot just average these modes, but. . <S>=sin 2 b =0. 50± 0. 06 S=. 52±. 05 -. 68±. 03 = -0. 16 ± 0. 06 Does u & c parts of Penguin contribute? Yes but S >0, ~0. 1 New Physics? ? ? The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 56

Electroweak penguins B K (*) + - • With l+l- pair, can have either pseudoscalar or vector mesons • New physics can affect both rates and kinematic distributions. BABAR hep-ex/0507005 (229 M BB) The Hadron Collider Physics Summer Schools, Belle prelim. hep-ex/0410006, 0508009 Fermilab August 9 -18, 2006 57

Asymmetry Lepton angular distribution in l+ l- rest frame Belle: lepton SM hep-ex/0508009 Ba. Bar The Hadron Collider Physics Summer Schools, 386 M BB But large errors & somewhat contradictory data from NP scenarios Ba. Bar Fermilab August 9 -18, 2006 58

Constraints on New Physics n n n Next to Minimal Flavor Violation construction Assume NP in tree decays is negligible Is there NP in B o -B o mixing? n Use Vub , A DK , Sy. K , Srr, m d , A SL = semileptonic asymmetry n Fit to h, r, r d , qd (or h, s) Agashe, Papucci, Perez, & Pirjol hep-ph/0509117 n The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 59

New Physics Constraints n n Amplitudes ~20% of SM still allowed in any region, more near 0 o Still a lot of room for New Physics in B d system The Hadron Collider Physics Summer Schools, s h Fermilab August 9 -18, 2006 60

B S System n New Physics almost unconstrained The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 61

G in B S Decays n G = GL - GH, where G=1/t of “light” “heavy” n n vs In B d system G is small, driven by common channels for B o & B o (i. e. p+p-) B S DS+(*) DS-(*), where CP+ outweighs CP- B S (recall CDF measured m S), CDF & D 0 have measurements, order of B(B→D(*)DS(*))~10% Recall G =2|G 12|cos f. S, where f. S is the CP violating phase in B S mixing, expected to be tiny in SM ~-2 l 2 h=-. 04 rad but effected by NP The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 62

Measuring f Phase of B S mixing n CP violation in B S mixing hf = ± 1, depending on f= CP+ or CP n Contrast with B o G(B o f)~e -t/t[1+A dir cos mt+sin f mt] n The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 63

Measuring f Without Flavor Tagging n Sum n Some sensitivity to tagging The Hadron Collider Physics Summer Schools, f without flavor Fermilab August 9 -18, 2006 64

Measuring f with B S J/y h (or f) n n B S J/y h (where h or p+p-po ) is a CP eigenstate similar to B o J/y K S. However, detecting the h is difficult for some hadron collider detectors J/y f is not a CP eigenstate , but is very useful in all experiments. Must take into account different spins: S, P, D. ∴use Transversity analysis Most sensitivity expected using flavor tagged analysis The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 65

D 0 Untagged Analysis n n The Hadron Collider Physics Summer Schools, D 0 has 978 ± 45 events f. S=-0. 79± 0. 56± 0. 01 (rad ) GS=0. 17± 0. 09± 0. 04 ps -1 G/G~0. 25± 0. 13 Fermilab August 9 -18, 2006 66

Future Experiments 67

B experiments at the LHCb § LHCb: first dedicated b experiment at a hadron collider, the LHC • Excellent vertexing • Excellent particle id CMS The Hadron Collider Physics Summer Schools, § Super B? Two efforts, one at Frascati and Super. Belle in Japan ATLAS Fermilab August 9 -18, 2006 68

LHCb Projections n (0. 02 rad) n K* + 2 fb -1 The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 69

Also ATLAS & CMS n ATLAS n CMS The Hadron Collider Physics Summer Schools, B S J/y f Fermilab August 9 -18, 2006 70

Will There Be a Super-B e+e- Machine? n Two proposals currently being pursued to make L~10 36, ~100 times current B factories n Super Belle at KEK n Linear-B scheme HER injection LER HER LER Bunch compressor and FF HER Bunch compressor and FF IP The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 71

Conclusions n n Much has been learned about the structure of matter & fundamental forces in nature using flavor decays; contributions from several generations of experiments at e+e-, fixed target and hadron colliders b & c decays will be used as incisive probes of New Physics. These effects appear in loops. We already are probing the Te. V scale. Flavor decays will be ever more important in understanding the nature of NP effects found at the LHC or Tevatron (i. e. SUSY, Extra Dimensions, Little Higgs etc. . . ) The next few years will see more results from Ba. Bar , Belle, CDF & D 0, but only Belle will remain post 2009 LHCb will be the first dedicated B physics experiment at a Hadron Collider. ATLAS & CMS also have B physics capability. There may be a Super B factory, possibly at KEK or at Frascati The Hadron Collider Physics Summer Schools, Fermilab August 9 -18, 2006 72