Beauty 2019 Opening Beauty at High { Precision Sensitivity Chris Quigg Fermilab Beauty 2019 · Ljubljana · September 30, 2019 See also “Dream Machines” 1808.06036 “Perspectives and Questions” zenodo.3376597 mailto:quigg@fnal.gov http://www.beauty2019.org/en/ https://arxiv.org/pdf/1808.06036.pdf https://doi.org/10.5281/zenodo.3376597 Origin Story . . . 400-GeV pN → µ+µ− + X VOLUME )9, NUMBER 20 PHYSICAL REVIEW LETTERS 14 NovEMBER 1977 04- TABLE II. Sensitivity of resonance parameters to continuum slope. Continuum subtraction of Eq. (1) but with b varied by + 2(T. Errors are statistical only. O c 0.2 ~ o.o t bI blab 9 l0 mass (GeV} Y M( (GeV) Bdo/dy(„-& (pb} ~, (Gev) B do/dy I -g (pb) ~3 (GeV) B do/dy / ~ -o (pb) per degree of freedom 9.40 + 0.013 0.18 + 0.01 10.00 ~ 0.04 0.068 + 0.007 10.43 + 0.12 0.014 + 0.006 14.1/16 9.40 + 0.014 0.17 + 0.01 10.01 ~ 0.04 0.061 + 0.007 10.38 + 0.16 0.008 + 0.007 15.4/16 b = 0.977 GeV 5 = 0.929 GeV FIG. 2. Excess of the data over the continuum fit of Eq. (1). Errors shown are statistical only. The solid curve is the three-peak fit; the dashed curve is the two-peak fit. TABLE I. Resonance fit parameters. Continuum subtraction is given by Eq. (1). Errors are statistical only. 2 peak 3 peak Y m, (GeV) Bda/dye o (pb) Y m, (GeV) Bdo./dye~ 0 (pb) M3 (GeV) B do/dyj, , (pb) y2 per degree of freedom 9.41 + 0.013 0.18+ 0.01 10.06 + 0.03 0.069 + 0.006 19.9/18 9.40 + 0.013 0.18+ 0.01 10.01+ 0.04 0.065+ 0.007 10.40 + 0.12 0.011+0.007 14.2/16 cise form of the continuum. The first test is to vary the slope parameter, b, in Eq. (1). Varia- tion each way by 20 yields the results given in Table II. A detailed study has been made of the error matrix representing correlated uncertain- ties in the multiparameter fit. The correlations increase the uncertainties of Tables I and II by &15%. Further uncertainties in the results presented above arise from the fact that the continnum fit is dominated by the data below 9 GeV. Nature could provide reasonable departures from Eq. (1) above this mass. These issues must wait for a large increase in the number of events, especial- ly above -11 GeV. However, the primary conclu- sions are independent of these uncertainties and may be summarized as follows: (i) The structure contains at least two narrow peaks: Y(9.4) and Y'(10.0). (ii) The cross section for Y(9.4), (Bda/ dy) i, „is' 0.18+ 0.07 pb/nucleon. (The error in- cludes our + 25/o absolute normalization uncertain- ty and. also the estimated uncertainty due to mod- el dependence of the acceptance calculation. ) (iii) There is evidence for a third peak Y "(10.4) although this is by no means established. Examination of the Pr and decay-angle distribu- tions of these peaks fails to show any gross dif- ference from adjoining continuum mass bins. An interesting quantity is the ratio of (Bda/ dy)l, , for Y(9.4) to the continuum cross section (d'o/dmdy)I, , at M = 9.40 GeV: This is 1.11 ~ 0.06 GeV. Table III presents mass splittings and cross sections (including systematic errors) under the two- and three-peak hypotheses and compares them with theoretical predictions to be discussed below. There is a growing literature which relates the Y to the bound state of a new quark (q) and its an antiquark (q).' " Eichten and Gottfried' have cal- culated the energy spacing to be expected from the potential model used in their accounting for the energy levels in charmonium. Their potential V(r) = —~4m, (m, )/r +r/a' (2) predicts line spacings and leptonic widths. The level spacings t Table III(a)] suggest that the shape of the potential may be oversimplified; we note that M(Y') -M(Y) is remarkably close to M (g') -M(4)" Table III(b) summarizes estimates of Bda/dyl, -, for qq states and ratios of then=2, 3 states to the ground state. Cascade models (Y produced as the radiative decay of a heavier P state formed by gluon amalgamation) and direct production processes seem to prefer Q = —& to Q =-', . We note finally that the ratios in Table III may re- quire modification due to the discrepancy between the observed spacing and the universally used 1241 E288 M(Υ′) −M(Υ) M(υ′′) −M(Υ′) Two-level fit 650 ± 30 MeV Three-level fit 610 ± 40 MeV 1000 ± 120 MeV M(ψ′) −M(J/ψ) ≈ 590 MeV General motivation: J/ψ, τ discoveries Kobayashi–Maskawa CPV insight Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 1 / 41 http://cds.cern.ch/record/1730227/files/vol17-issue7-8-p223-e.pdf?version=1 https://doi.org/10.1103/PhysRevLett.39.1240 https://doi.org/10.1143/PTP.49.652 Eichten & Gottfried: CESR Proposal (November 1976) Volume 66B, number 3 PHYSICS LETTERS 31 January 1977 H E A V Y Q U A R K S I N e ÷ e - ANNIHILATION* E. EICHTEN and K. G O T T F R I E D Laboratory o f Nuclear Studies, Cornell University, Ithaca, New York, 14853, USA Received 16 November 1976 There are many speculations that there exist quarks Q considerably heavier than the charmed quark. Their QQ states will display a far richer spectrum of monochromatic photon and hadron transitions than charmonium. The most important features of this spectrum - in particular, its dependence on the mass of Q - are outlined. The l i t e r a t u r e bristles [ 1 ] w i t h c o n j e c t u r e d quarks c o n s i d e r a b l y heavier t h a n the c h a r m e d quark. We d o n o t w a n t to pass j u d g e m e n t on the p l a u s i b i l i t y o f these speculations here. Our principal p u r p o s e is t o p o i n t out a quite obvious fact: i f such super-heavy quarks Q ac- tually exist and have masses mQ b e l o w 15 G e V , the new g e n e r a t i o n o f e+e - storage rings will find a spec- trum o f Q(~ b o u n d states and resonances t h a t is far richer than the c c s p e c t r u m in the 3 - 5 GeV region. This is so because for mQ ~> 3.5 GeV we e x p e c t three 351 b o u n d states b e l o w the t h r e s h o l d for the Zweig- allowed decays o f QQ. As a c o n s e q u e n c e , the QQ s p e c t r u m will d i s p l a y a very i n t r i c a t e and c o m p l e x array o f p h o t o n and h a d r o n transitions. In a d d i t i o n , the region above the Zweig-decay t h r e s h o l d will con- tain a rich a s s o r t m e n t o f r a t h e r n a r r o w resonances. Planning for e x p e r i m e n t s at CESR, PEP and P E T R A might b e a r this e n t i c i n g p o s s i b i l i t y in m i n d . T h a t an increase o f q u a r k mass leads to s t r o n g e r b i n d i n g o f Q(~ states is obvious w i t h o u t any t h e o r y . Thus sg j u s t fails to have a b o u n d 1 - s t a t e , whereas cg has two. Hence we e x p e c t f u r t h e r QQ 1 - states can be b o u n d b y a s u f f i c i e n t l y large increase o f m Q , and it o n l y remains to q u a n t i f y " s u f f i c i e n t l y " . The success o f the c h a r m o n i u m m o d e l [ 2 - 4 ] allows one to c o m p u t e the m Q - d e p e n d e n c e o f the QQ s p e c t r u m with a c o n s i d e r a b l e degree o f c o n f i d e n c e , and t h e r e b y to e s t i m a t e the value o f m Q where a t h i r d 3S s t a t e is b o u n d . As in c h a r m o n i u m , we [4] use a static QQ interac- tion v(r) = ! + r S r a 2 . (1) * Supported in part by the National Science Foundation. 286 I000 [~((iDick~75:(:i;L4'7.4:.::;~":':'~:~::";::::'::;;'~";#'~-;;~~:' W _ g , ~ _ ~ o o m~ 0 i I I I 2 3 4 5 6 FFi O (GeV) Fig. 1. QQ excitation energies as a function of quark mass. The energies shown are found from the Schr6dinger equation with (1) as potential. All relativistic corrections to the excita- tion spectrum are ignored. The onset of the Q~+ Qq conti- nuum is also shown. Its position relative to the QQ spectrum does depend on various corrections; see the discussion related to eqs. (2) and (3). The length a is assumed to be a universal c o n s t a n t cha- racterizing the q u a r k c o n f i n e m e n t i n t e r a c t i o n . The C o u l o m b i c i n t e r a c t i o n has a s t r e n g t h % ( m ~ ) whose mQ d e p e n d e n c e is given b y the w e l l - k n o w n renormali- z a t i o n g r o u p f o r m u l a from c o l o r gauge t h e o r y . F r o m our analysis [51 o f the c~ system, we have a = 2.22 GeV - 1 and a s ( m 2) = 0.19. The QQ e x c i t a t i o n s p e c t r u m p r e d i c t e d b y V ( r ) is shown in fig. 1 as a f u n c t i o n o f mQ. ( F i n e s t r u c t u r e effects - n o t y e t u n d e r s t o o d in c h a r m o n i u m - are E (2S) − E (1S) ≈ 420 MeV General: # of narrow 3S1 levels ∝ √ MQ Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 2 / 41 https://doi.org/10.1016/0370-2693(77)90882-6 Why choose MQ = 5 GeV? Excess events at high inelasticity observed in ν̄µN → µ+ + anything V −A: dσ(νq)/dy ∝ 1 dσ(ν̄q)/dy ∝ (1 −y)2 “high-y anomaly” could be explained by( u b ) R with mb ≈ 4 – 5 GeV Also at Budapest 1977. . . CDHS experiment ruled out the high-y anomaly Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 3 / 41 https://doi.org/10.1103/PhysRevLett.36.1478 https://doi.org/10.1103/PhysRevD.14.70 https://doi.org/10.1103/PhysRevD.14.70 https://doi.org/10.1103/PhysRevD.14.70 https://doi.org/10.1103/PhysRevLett.39.433 Υ(1S), Υ(2S) leptonic widths ; Qb = −13 (DORIS, 1978) Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 4 / 41 CESR resolves three narrow Υ states (1979–80) VOLUME 44, NUMBER 17 PHYSICAL REVIEW LETTERS 28 APR&L 1980 20— IO- 14— l2— c IO 0 a) 8- CA COe0 O I ~ I 942 9.44 I I I I & I 9.46 9.48 9.50 2- 0 I ~ ~ I ~ I I I I 9.97 9.99 IO.O I I 0,03 IO.05 6- 4-- 'i, it II 2 0 I I I I I I I I I I0.32 I 0.34 I0.36 I 0.38 10.40 W = Center of mass energy, GeV FIG. 3. Measured cross sections, including cor- rections for backgrounds and for acceptance, but not for radiative effects. Errors shown are statistical only. There is an additional systematic normalization error of + 20/o arising from uncertainties in efficiencies and in the luminosity calibration. The energy scale has a calibration accuracy of 30 MeV. The curves show the best fit described in the text. orbit. Although CESR energy settings were found by repeated resonance scans to be reproducible to better than 0.01/o accuracy, there is at present an uncertainty in the overall calibration scale factor amounting to about 0.3%. The resonances near 9.4 and 10.0 GeV match the & and Y' observed first by Herb et a~.~ and confirmed at the DORl8 e+e ring. ' 4 Because of the superior energy resolution of the CESR machine, our resonance peaks appear about two times higher and narrower than those observed at DORIS. The resonance near 10.3 GeV is the first confirmation of the &" claimed by Ueno et al.' We fit the data by three very narrow resonan- ces, each with a radiative tail convoluted with a Gaussian energy spread, added to a continuum. ' A single fit to the three peaks with a common energy spread proportional to ~' and a common continuum proportional to ~ ' has a X equal to 0.94 per degree of freedom. The rms energy spread is 4.1~0.3 MeV at ~=10 GeV, as ex- pected from synchrotron radiation and beam- orbit dynamics in CESR. Individual fits to the three peaks with independent continuum levels and peak widths give results for the rms energy spread and for 1"„which remain within the er- rors quoted. From the radiatively corrected area under each peak we extract the leptonic width &„, using the relation fo'd~= 6m'1;, /M'. The results are given in Table I. We list our results in terms of relative masses and leptonic widths, since systematic errors in these quanti- ties tend to cancel. Our measurements agree with those reported by Bohringer et al. ' On the Y and &' our results agree with those from DORIS ' for the mass difference but not for the I;, ratio. Because of rather large uncertainties in the contribution of background processes such as & production and two-photon collisions, we do not regard our present measurement of the con- tinuum cross section as definitive. Mass differences have been predicted by as- suming that the Y, Y', and &" are the triplet IS, 2S, and 3S states of a bb quark pair bound in a phenomenological potential, essentially the same as that responsible for the psion spectrum. When the potential is adjusted to fit masses in the psion region and earlier measurements of the &'-Y difference, the predictions for the Y"-T mass difference' "range from 881 to 898 MeV, TABLE I. Measured masses and leptonic widths for the second and third & states, relative to values for the first state, &(9.4). The first error is statistical, the second systematic. M-M(9. 4) (MeV) Y'(10.0), DORIS (Ref. 3) Y'(10.0), DORIS (Ref. 4) &'(10.0), this experiment &"(10.3), this experiment 555+ 11 560+ 10 560.7+ 0.8+ 3.0 891.1+ 0.7 + 5.0 0.23 + 0.08 0.31+ 0.09 0.44+ 0.06+ 0.04 0.35 + 0.04 + 0.03 1110 CLEO VOLUME 44, NUMBER 17 PHYSICAL REVIEW LETTERS 28 APRiL 1980 all signals were digitized and recorded on tape. This trigger gave an event rate of 0.3 Hz for a luminosity of 1 pb ' s '. A typical fill of CESR lasts 3 to 5 hours yielding an integrated lumi- nosity of up to -15 nb '. The integrated luminos- ity for each run was measured by detecting and counting small-angle (40 to 80 mrad) collinear Bhabha scatter s w ith lead-scintillator sandwich shower detectors. The long-term stability of the luminosity monitor is confirmed by the yield of large-angle Bhabha scattering events in the NaI array. Because of the limited solid angle of the NaI array as used, a major fraction of the hadronic e e annihilations gave very few particles in the detector. Rather than trying to identify all had- ronic events, which would result in an unaccept- able amount of background, our aim in the analy- sis was to obtain a clean sample through the use of strict event- selection criteria. Fundamental in all criteria used was the identification of mini- mum-ionizing hadrons. At normal incidence, minimum-ionizing particles deposit 15 MeV in the first four Nal layers and - 68 MeV in the last layer of a single sector. In all scans one unam- biguous and isolated minimum-ionizing track plus at least two other tracks or showers were required. All data were scanned by physicists and with computer programs. The acceptance criteria for data presented were determined by maximizing detection eff iciency while maintain- ing the background level well below l0'%%uo of the continuum cross section. The overall efficien- cies for detecting continuum and Y events are, respectively, 28% and 37/o. These values are ob- tained by use of the cross sections measured at DORIS'' (g„„,=3.8 nb at 9.4 GeV, o ~»&=18.5 nb after correcting for the difference in beam en- ergy spread at CESR and DORIS). Absolute nor- malization was obtained by use of large-angle Bhabha-scattering data. The difference in effi- ciencies is due to the fact that & decays have higher multiplicity and sphericity than continuum events. ' The actual number of &, Y', and&" events detected above continuum were, respec- tively, 214, 53, and 133. From the continuum around the three ~'s we collected 272 events. The major sources of background were (i) far single beam-wall and beam-gas interactions, (ii) close beam-wall interactions, (iii) close beam-gas interactions, and (iv) cosmic rays. Case (i) was trivially removed by the require- ment of an isolated track. Cases (ii) and (iii) oc- cur with very small probability of producing pene- trating hadrons at 8 =90'~ 30' with 5-GeV elec- trons. Case (ii), which is more frequent, is also recognizable by tracks crossing azimuthal sector boundaries. Case (iv) was rejected by the re- quirement of three tracks. We point out that the minimal residual background does not affect the results presented here. The hadronic yield is presented in Fig. 2, plot- ted in arbitrary units proportional to the ratio of detected events to small-angle Bhabha yield. In this way, the energy dependence (- I/E') of the single-photon processes is removed. The hori- 6.0 5Q- 40 C o Z.o ~ 2.0- 1.0- I6 Il 16 6 I ic 6 9.48 9.96 I 9.44 ~ W Ii ll i1' P ;,E- 16 I6 6 i.16-Ilk .. ~ g 'I]~ „][Ii T&l & 'Q II II k-k-~ &-'-"&~~"& i 0 I I I 9.40 10.00 10.04 10.52 10.&6 10.40 e e MASS (GeV) FIG. 2. The number of hadronic events, normalized to the small-~~pie Bhabha yield. The solid line indicates a fit described in the text. 1113 CUSB Υ(4S) launches B physics (1980) Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 5 / 41 https://doi.org/10.1103/PhysRevLett.44.1108 https://doi.org/10.1103/PhysRevLett.44.1111 https://doi.org/10.1103/PhysRevLett.46.84 Rich spectrum of (bb̄) levels Observed Predicted E J E ic h te n 14 states below threshold still unobserved Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 6 / 41 Charmonium-associated states not pure charmonium All these states near or above threshold near threshold states have possible molecule component “¿. . . ?” need more info if JPC = 0++, ¿X (3915)? possible 23P2 ¿ψ(4660)? possible 5S ψ(4230), ¿ψ(4360)? possible hybrids E J E ic h te n When can we find (bb̄) analogues? Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 7 / 41 Quarkonium-associated states: M & threshold: X (3872) etc. Mostly narrow, seen in hadronic transitions or decays What are they? Quarkonium (+ coupled-channels, thresholds) Threshold effects New body plans: quarkonium hybrids (qq̄g) two-quark–two-antiquark states, including dimeson “molecules” tetraquarks diquarkonium · hadroquarkonium and superpositions! (crypto)pentaquarks Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 8 / 41 CP violation might be large and observable (1980–81) Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 9 / 41 https://doi.org/10.1103/PhysRevLett.45.952 https://doi.org/10.1016/0550-3213(81)90519-8 Reconstruction of B Mesons (CLEO, 1983) PDG: I,J,P still need confirmation! Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 10 / 41 https://doi.org/10.1103/PhysRevLett.50.881 http://pdg.lbl.gov/2019/tables/contents_tables_mesons.html MAC & Mark II find unexpectedly long b-hadron lifetime (1983) Charm lifetimes [fs] D+ : 1040 ± 7 D0 : 410.1 ± 1.5 Ds : 504 ± 4 Λc : 200 ± 6 Ξ+c : 442 ± 26 Ξ0c : 112 +13 −10 Ωc : 268 +10 −26 Evidence for small |Vcb| ≈ 0.05 Beauty lifetimes [fs] B+ : 1638 ± 4 B0 : 1519 ± 4 Bs : 1510 ± 4 Λb : 1471 ± 9 Ξ−b : 1572 ± 40 Ξ0b : 1480 ± 30 Ωb : 1640 +180 −170 Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 11 / 41 https://doi.org/10.1103/PhysRevLett.51.1022 https://doi.org/10.1103/PhysRevLett.51.1316 https://doi.org/10.1103/PhysRevLett.51.1316 B0-B̄0 Mixing: the golden event from ARGUS (1987) Large mixing ; large mt UA1 same-sign dimuons ; B0s – B̄ 0 s mixing (1987) Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 12 / 41 https://doi.org/10.1016/0370-2693(87)91177-4 https://doi.org/10.1016/0370-2693(87)90288-7 b properties imply top-quark partner must exist (1992) Lb ≡ 2I3L − 2Qb sin2 θW, Rb ≡ 2I3R − 2Qb sin2 θW Γ(Z 0 → bb̄) measures (L2b + R 2 b ), A (bb̄) peak (L 2 b −R 2 b )/(L 2 b + R 2 b ), LE FB asym A(bb̄) ∝ (Rb −Lb) I3L = −12 ; I3R = 0 Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 13 / 41 https://doi.org/10.1103/PhysRevD.45.3262 Observation of large CP violation in B0 decays (BABAR & Belle, 2001) sin 2β ≈ 0.59 sin 2φ1 ≈ 0.99 Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 14 / 41 https://doi.org/10.1103/PhysRevLett.87.091801 https://doi.org/10.1103/PhysRevLett.87.091802 Observation of B0s – B̄ 0 s Oscillations (CDF, 2006) ∆ms ≈ 17.77 ps−1 Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 15 / 41 https://doi.org/10.1103/PhysRevLett.97.242003 Precision tests of the CKM paradigm 1− 0.5− 0 0.5 1 ρ 1− 0.5− 0 0.5 1 η γ β α sm∆ dm∆ d m∆ K ε cbV ubV summer18 )σPull ( | ud |V 0.2 ) e3 B(K 1.3 ) e2 B(K 1.8 ) 2μ B(K 0.1 )K2τB( 2.2 not lattice | cd |V 0.5 not lattice | cs |V 0.0 )νlπ →B(D 0.1 )νKl→B(D 0.1 )ν τ→ s B(D 1.6 )νμ→ s B(D 0.5 )νμ→B(D 1.6 semilep | cb |V 0.2 semilep | ub |V 0.3 )ντ→B(B 1.1 dmΔ 1.7 smΔ 1.1 Kε 0.1 βcos 2 0.8 βsin 2 1.0 α 1.2 γ 1.1 s φ 0.5 μμ→sB 1.0 0 0.5 1 1.5 2 2.5 Summer 18 CKM f i t t e r Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 16 / 41 http://www.utfit.org/UTfit/ResultsSummer2018SM http://ckmfitter.in2p3.fr/www/results/plots_summer18/ckm_res_summer18.html Reconstruction of Bc meson (CDF, 2006) M(Bc ) = 6274.9 ± 0.8 MeV (Test of lattice QCD prediction) Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 17 / 41 https://doi.org/10.1103/PhysRevLett.96.082002 Mesons with beauty and charm: stress test for NRQM, LQCD Bc : weak decays only b → c c → s bc̄ → W− Bc → J/ψπ: (QQ̄) transmutation Rich (bc̄) excitation spectrum; interpolates J/ψ, Υ ( 6= masses) Excited states below BD → Bc + . . . Bc (2S) → Bc (1S) + ππ P states: γ transitions Many states observable at LHC, TeraZ Update: Eichten & CQ (2019) using “frozen-αs” potential, new approach to spin splittings 7600 7000 6200 M as s [M eV ] 7400 7200 6400 6600 6800 12–15 narrow levels Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 18 / 41 http://arxiv.org/abs/arXiv:1902.09735 http://arxiv.org/abs/arXiv:1902.09735 Observing the Bc spectrum: ππ transitions Combine predicted production rates (BCVEGPY2.2) with calculated branching fractions to obtain expectations for ππ transition rates ; peak heights: B∗′c /B ′ c ≈ 2.5 M1 B∗c → /γBc unobserved [M(B∗′c ) −M(B′c )] − [M(B∗c ) −M(Bc )] ≈−23 MeV: B∗′c lower peak 2S → ππ+ 1S transitions observed by ATLAS, CMS, LHCb CMS separation: −29 MeV d σ /d M [n b /M eV ] 2.0 1.0 0.5 1.5 0 6820 M(Bcπ +π–) [MeV] 6830 6840 6850 6860 6870 6880 6890 Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 19 / 41 https://doi.org/10.1103/PhysRevD.99.054025 https://doi.org/10.1103/PhysRevLett.122.132001 Observing the Bc spectrum: E1 transitions E1 spectroscopy in the (bb̄) family: LHC experiments discovered χ′′b1,χ ′′ b2. Incentive for the search: 2S → 2P and 2P → 1S transitions, assuming missing B∗c → Bc /γ in the reconstruction. 3S, 3P yields ≈ 1 4 × 2P → 1S lines, but higher γ energies may aid detection. 33P2(7154) → B∗c γ(777 MeV) Encourage search for (3, 2)P(bc̄). k [MeV] σ B [n b/ M eV ] 100 150 200 450400250 500300 350 0.0 0.5 1.5 1.0 2.5 2.0 3.0 3.5 Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 20 / 41 https://doi.org/10.1103/PhysRevD.99.054025 https://doi.org/10.1103/PhysRevD.99.054025 Mesons with beauty and charm: states above flavor threshold 3S states above threshold have significant decay widths 3P states just below threshold; J = 1 may have significant mixing Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 21 / 41 https://doi.org/10.1103/PhysRevD.99.054025 https://doi.org/10.1103/PhysRevD.99.054025 Strong dynamics greatly simplifies for MQ � ΛQCD Symmetry independent of dynamics of light degrees of freedom Heavy-light systems: (cq̄), (bq̄), (cqq), (bqq), (ccq), (cbq), (bbq) (q = u,d,s) HQET: systematic expansion in powers of ΛQCD/MQ HQS relations among spectra in [(cq̄), (bq̄), (ccq), (bcq), (bbq)] and [(cqq), (bqq)] QED analogue: hydrogen atom (e−p+) Nonrelativistic (QQ̄): bound-state masses M≈ 2MQ NRQCD: systematic expansion in powers of v/c Quarkonium systems: (cc̄), (bb̄), (bc̄) heavy quark velocity: pQ/MQ ≈ v/c � 1 binding energy: 2MQ −M≈ MQv 2/c2 QED analogs: positronium (e+e−), “true” muonium (µ+µ−), muonium (µ+e−) Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 22 / 41 Heavy quark symmetry ⇒ stable heavy tetraquarks QiQjq̄kq̄l (QQ) q̄ q̄ (QQ) q̄ q̄ (QQ) q̄ q̄ q̄ q̄ Q Q HQS relates DHTQ mass to masses of QQq, Qqq, Qq̄. Lightest bbūd̄, bbūs̄, bbd̄s̄ states: (likely) no strong decays. Heavier bbq̄kq̄l , ccq̄kq̄l , bcq̄kq̄l → Qq̄ + Qq̄ might be seen as “double-flavor” resonances near threshold. Observing a weakly decaying double-beauty state would establish the existence of tetraquarks and illuminate the role of heavy color-3̄ diquarks as hadron constituents. Eichten & CQ 1707.09575 Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 23 / 41 https://doi.org/10.1103/PhysRevLett.119.202002 HQS relations for ground-state tetraquark masses m(QiQjq̄kq̄l ) −m(QiQjqm) = m(Qxqkql ) −m(Qxq̄m) + finite-mass corrections RHS is determined from data One doubly heavy baryon observed, Ξcc ; others from model calculations ? LHCb: M(Ξ++cc ) = 3621.40 ± 0.78 MeV ?We adopt Karliner & Rosner, PRD 90, 094007 (2014) Strong decays (QiQjq̄kq̄l ) 6→ (QiQjqm) + (q̄kq̄lq̄m) ∀ ground states Consider decays to pairs of heavy–light mesons case-by-case Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 24 / 41 https://dx.doi.org/10.1103/PhysRevLett.119.112001 https://dx.doi.org/10.1103/PhysRevD.90.094007 Expectations for ground-state tetraquark masses, in MeV State JP m(QiQjq̄kq̄l ) Decay Channel Q [MeV] {cc}[ūd̄] 1+ 3978 D+D∗0 3876 102 {cc}[q̄k s̄] 1+ 4156 D+D∗+s 3977 179 {cc}{q̄kq̄l} 0+, 1+, 2+ 4146, 4167, 4210 D+D0,D+D∗0 3734, 3876 412, 292, 476 [bc][ūd̄] 0+ 7229 B−D+/B0D0 7146 83 [bc][q̄k s̄] 0 + 7406 BsD 7236 170 [bc]{q̄kq̄l} 1+ 7439 B∗D/BD∗ 7190/7290 249 {bc}[ūd̄] 1+ 7272 B∗D/BD∗ 7190/7290 82 {bc}[q̄k s̄] 1+ 7445 DB∗s 7282 163 {bc}{q̄kq̄l} 0+, 1+, 2+ 7461, 7472, 7493 BD/B∗D 7146/7190 317, 282, 349 {bb}[ūd̄] 1+ 10482 B−B̄∗0 10603 −121 {bb}[q̄k s̄] 1+ 10643 B̄B̄∗s /B̄sB̄∗ 10695/10691 −48 {bb}{q̄kq̄l} 0+, 1+, 2+ 10674, 10681, 10695 B−B0,B−B∗0 10559, 10603 115, 78, 136 Cf. M. Karliner & J. L. Rosner model, Phys. Rev. Lett. 119, 202001 (2017) [arXiv:1707.07666]. Estimate deeper binding, so additional bc and cc candidates. Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 25 / 41 https://dx.doi.org/10.1103/PhysRevLett.119.202001 Real-world candidates for stable tetraquarks JP = 1+ {bb}[ūd̄] meson, bound by 121 MeV (77 MeV below B−B̄0γ) T {bb} [ūd̄] (10482)−→ Ξ0bcp̄, B −D+π−, and B−D+`−ν̄︸ ︷︷ ︸ manifestly weak! JP = 1+ {bb}[ūs̄] and {bb}[d̄s̄] mesons, bound by 48 MeV (3 MeV below BBsγ) T {bb} [ūs̄] (10643)−→ Ξ0bc Σ − T {bb} [d̄s̄] (10643)0→ Ξ0bc (Λ̄, Σ 0 ) Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 26 / 41 Unstable doubly heavy tetraquarks Resonances in “wrong-sign” (double flavor) combinations DD,DB,BB? JP = 1+ T {cc}++ [d̄s̄] (4156)→ D+D∗+s : prima facie evidence for non-qq̄ level Double charge / double charm (New kind of resonance: no attractive force at the meson–meson level.) Also, 1+ T {bb}{q̄kq̄l}(10681) 0,−,−−, Q = +78 MeV 1+ T {bc} [ūd̄] (7272)0, Q = +82 MeV 0+ T [bc] [ūd̄] (7229)0, Q = +83 MeV 1+ T {cc} [ūd̄] (3978)+, Q = +102 MeV Aside: 3D3 and 3F4 cc̄ mesons still to be identified in DD̄, etc. LHCb 3D3 candidate (2019) Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 27 / 41 https:\dx.doi.org/10.1007/JHEP07(2019)035 Homework for experiment T 1. Look for double-flavor resonances near threshold. T 2. Measure cross sections for final states containing 4 heavies: QiQ̄iQjQ̄j . T 3. Discover and determine masses of doubly-heavy baryons. needed to implement HQS calculation of tetraquark masses intrinsic interest in these states: compare heavy–light mesons, possible core excitations Resolve Ξ+cc uncertainty (SELEX/LHCb) T 4. Find stable tetraquarks through weak decays. Lifetime: ∼ 1 3 ps ?? Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 28 / 41 https://doi.org/10.1103/PhysRevLett.89.112001 https://arxiv.org/pdf/1909.12273 Homework for theory T 5. Develop expectations for production. A. Ali et al., “Prospects of discovering stable double-heavy tetraquarks at a Tera-Z factory,” arXiv:1805.02535 → PLB. T 6. Refine lifetime estimates for stable states. T 7. Understand how color configurations evolve with QQ (and q̄q̄) masses. J.-M. Richard, et al., “Few-body quark dynamics for doubly-heavy baryons and tetraquarks,” arXiv:1803.06155, Phys. Rev. C 97, 035211 (2018). T 8. Investigate stability of different body plans in the heavy-quark limit. . . . up to (QiQj )(QkQl )(QmQn): B = 2, but QpQqQr color structure? Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 29 / 41 https://arxiv.org/abs/1805.02535 https://doi.org/10.1016/j.physletb.2018.05.055 https://arxiv.org/abs/1803.06155 https://doi.org/10.1103/PhysRevC.97.035211 Flavor: the problem of identity What makes an electron an electron, a top quark a top quark, . . . ? We do not have a clear view of how to approach the diverse character of the constituents of matter CKM paradigm: extraordinarily fruitful framework in hadron sector BUT—many parameters: no clue what determines them, nor at what energy scale they are set Even if Higgs mechanism explains how masses and mixing angles arise, we do not know why they have the values we observe Physics beyond the standard model! Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 30 / 41 Flavor: the problem of identity (continued) Parameters of the Standard Model 3 Coupling parameters, αs, αem, sin 2 θW 2 Parameters of the Higgs potential 1 Vacuum phase (QCD) 6 Quark masses 3 Quark mixing angles 1 CP-violating phase 3 Charged-lepton masses 3 Neutrino masses 3 Leptonic mixing angles 1 Leptonic CP-violating phase (+ Majorana phases?) 26+ Arbitrary parameters Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 31 / 41 Questions concerning the problem of identity F1. Can we find evidence of right-handed charged-current interactions? Is nature built on a fundamentally asymmetrical plan, or are the right-handed weak interactions simply too feeble for us to have observed until now, reflecting an underlying hidden symmetry? F2. What is the relationship of left-handed and right-handed fermions? F3. Are there additional electroweak gauge bosons, beyond W± and Z ? F4. Are there additional kinds of matter? F5. Is charged-current universality exact? What about lepton-flavor universality? Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 32 / 41 B(s,d) → `+`− search and observation SM: B(Bs → µ+µ−) = (3.66 ± 0.23) × 10−9 B(Bd → µ+µ−) = (1.06 ± 0.09) × 10−10 Recent CMS: B(Bs → µ+µ−) = [2.9+0.7−0.4 ± 0.2(fs/fd )] × 10 −9 Coming: τ(Bs → µ+µ−), B(d,s) → e+e− searches Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 33 / 41 https://indico.cern.ch/event/836356/attachments/1903102/3154081/slides.pdf https://doi.org/10.1103/PhysRevLett.112.101801 https://doi.org/10.1103/PhysRevLett.112.101801 https://cds.cern.ch/record/2684828/files/BPH-16-004-pas.pdf K + → π+νν̄ search and observation (0.84 ± 0.10) × 10−10 90% CL: < 1.85 × 10−10 < 1.85 × 10−10 @ 90% CLChris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 34 / 41 https://indico.cern.ch/event/846814/attachments/1903630/3161337/CERN_seminar_23_09_2019.pdf https://doi.org/10.1007/JHEP11(2015)033 Searches for flavor-changing neutral currents F6. Where are flavor-changing neutral currents in quark transitions? In the standard model, these are absent at tree level and highly suppressed by the Glashow–Iliopouolos–Maiani mechanism. They arise generically in proposals for physics beyond the standard model, and need to be controlled. And yet we have made no sightings! Why not? Bs,d → µ+µ−, K + → π+νν̄, . . . F7. Can we detect flavor-violating decays H(125) → τ±µ∓, . . . ? F8. How well can we test the standard-model correlation among B(K + → π+νν̄), B(Bs → µ+µ−), and the quark-mixing matrix parameter γ? Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 35 / 41 Have we found the “periodic table” of elementary particles? Pointlike spin-1/2 constituents (r < 10−18 m) SU(3)c ⊗ SU(2)L ⊗ U(1)Y→ SU(3)c ⊗ U(1)em F9. What do generations mean? Is there a family symmetry? F10. Why are there three families of quarks and leptons? (Is it so?) F11. Are there new species of quarks and leptons? exotic charges? Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 36 / 41 More questions concerning the problem of identity F12. Is there any link to a dark sector? F13. What will resolve the disparate values of |Vub| and |Vcb| measured in inclusive and exclusive decays? F14. Is the 3 × 3 (CKM) quark-mixing matrix unitary? F15. Why is isospin a good symmetry? What does it mean? F16. Can we find evidence for charged-lepton flavor violation? F17. Will we establish and diagnose a break in the SM? F18. Do flavor parameters mean anything at all? Contrast the landscape perspective. F19. If flavor parameters have meaning (beyond engineering information), what is the meta-question? Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 37 / 41 The top quark touches many topics in particle physics t1. How well can we constrain Vtb in single-top production, . . . ? t2. How well can we constrain the top-quark lifetime? How free is t? Recent ATLAS: Γ(t) = 1.9 ± 0.5 GeV (SM 1.32 GeV) t3. Are there tt̄ resonances? t4. Can we find evidence of flavor-changing top decays t → (Z,γ)(c,u)? Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 38 / 41 http://cdsweb.cern.ch/record/2684952 Questions about EWSB and the Higgs Sector H1. Is H(125) the only member of its clan? Might there be others—charged or neutral—at higher or lower masses? H2. Does H(125) fully account for electroweak symmetry breaking? Does it match standard-model branching fractions to gauge bosons? Are absolute couplings to W and Z as expected in the standard model? H3. Are all production rates as expected? Any surprise sources of H(125)? H4. What accounts for the immense range of fermion masses? H5. Is the Higgs field the only source of fermion masses? Are fermion couplings proportional to fermion masses? µ+µ− soon? How can we detect H → cc̄? e+e−?? (basis of chemistry) H6. What role does the Higgs field play in generating neutrino masses? Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 39 / 41 More questions about EWSB and the Higgs Sector H7. Can we establish or exclude decays to new particles? Does H(125) act as a portal to hidden sectors? When can we measure ΓH ? H8. Can we detect flavor-violating decays (τ±µ∓, . . . )? H9. Do loop-induced decays (gg,γγ,γZ ) occur at standard-model rates? H10. What can we learn from rare decays (J/ψ γ, Υ γ, . . . )? H11. Does the EW vacuum seem stable, or suggest a new physics scale? H12. Can we find signs of new strong dynamics or (partial) compositeness? H13. Can we establish the HHH trilinear self-coupling? H14. How well can we test the notion that H regulates Higgs–Goldstone scattering, i.e., tames the high-energy behavior of WW scattering? H15. Is the electroweak phase transition first-order? See Dawson, Englert, Plehn, arXiv:1808.01324 ; Phys. Rep. Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 40 / 41 https://arxiv.org/abs/1808.01324 https://doi.org/10.1016/j.physrep.2019.05.001 An exercise for all of us How do you assess the scientific potential for Beauty and in general of (a) The High-Luminosity LHC? (b) The High-Energy LHC? (c) A 100-TeV pp Collider (FCC-hh)? (d) A 250-GeV ILC? (e) A circular Higgs factory (FCC-ee or CEPC)? (f) A 380-GeV CLIC? (g) A µ+µ− → H Higgs factory? (h) LHeC / FCC-eh? (or an electron–ion collider?) (i) A muon-storage-ring neutrino factory? (j) A multi-TeV muon collider? (k) The instrument of your dreams? Chris Quigg Beauty 2019 Opening Ljubljana · 30.09.2019 41 / 41