15th workshop on non-perturbative Quantum Chromodynamics Central exclusive production at RHIC and LHC Antoni Szczurek 1,, Piotr Lebiedowicz 1, Otto Nachtmann 3, 1 Institute of Nuclear Physics PAN Kraków University of Rzeszów 3 Institute für Theoretische Physik, Universität Heidelberg Paris, June 11-13, 18
Our works on central production Our recent works on central production: 1. Production of π + π pairs in pp ppπ + π reaction.. Production of K + K pairs in pp ppk + K reaction. 3. Production of two pairs of π + π in pp ppπ + π π + π reaction Three pomeron exchanges (!) 4. Production of φφ final state pp ppk + K K + K reaction in quest for glueballs 5. Production of p p pairs in pp pp(p p) reaction interesting spin effects for Regge-like reactions. 6. Exclusive production of J/ψ meson in pp ppj/ψ and semiexclusive processes. 7. Production of e + e or µ + µ pairs via γγ fusion with photon transverse momenta. 8. Production of W + W pairs via γγ fusion with photon transverse momenta.
Regge approach At higher energies s > -3 GeV, meson-exchange approach stops to work. Regge approach was proposed. Exchange of so-called Regge trajectories. In the past rather two-body processes were studied. An example is elastic scattering. pp pp, p p p p π + p π + p, π p π p K + p K + p, K p K p Several Regge trajectories are necessary to describe the two-body reactions: (a) leading trajectory (trajectories): pomeron (C=1), odderon (C=-1) (not clearly identified) (b) subleading trajectories: f a (C=+1), ω ρ (C=-1) One can understand total cross sections in the Regge picture. Extension of the Regge approach to 3, 4, etc, processes possible only now. Not yet tested. Use coupling constants extracted from the elastic scattering and total cross sections.
Tensor pomeron model In our recent works all amplitudes are calculated assuming tensor pomeron model proposed by Nachtmann et al., Annals Phys. 34 (14) 31. It is often said that Pomeron has vacuum quantum numbers. This is true for color but not spin degrees of freedom. Often vector pomeron is used in practical calculations. Vector pomeron is inconsistent with Field Theory. Tensor pomeron consistent with so called r 5 observable measured in proton-proton elastic scattering by STAR C. Ewerz, P. Lebiedowicz, O. Nachtmann and A. Szczurek, Phys. Lett. B763 (16) 38. Feynman rules for exchanges of the soft objects have been proposed (vertices, propagators). We keep checking whether it works for different other processes. So far yes! Further tests are needed. Tensor pomeron, see also Chung-I Tan et al. and E. Shuryak et al.
Tensor pomeron The propagator of the tensor-pomeron exchange is written as: i (IP) µν,κλ (s, t) = 1 (g µκ g νλ + g µλ g νκ 1 ) 4s g µνg κλ ( isα IP )αip(t) 1 (1) and fulfils the following relations (IP) µν,κλ (s, t) = (IP) νµ,κλ (s, t) = (IP) µν,λκ (s, t) = (IP) κλ,µν (s, t), g µν (IP) µν,κλ (s, t) =, gκλ (IP) µν,κλ (s, t) =. () It gives by construction the same result for pp pp elastic scattering as traditional Regge approach.
Exclusive reactions Consider exclusive process pp ppm M (pp ppr or even pp ppm MM M) Calculate (helicity-dependent) amplitude M pp ppm M Calculate differential cross sections: dσ = 1 s M pp ppm M (3) (π) 4 δ 4 (p a + p b p 1 p p 3 p 4 ) d 3 p 1 (π) 3 E 1 d 3 p (π) 3 E d 3 p 3 (π) 3 E 3 d 3 p 4 (π) 3 E 4 (4) Any differential distribution can be calculated Include absorption effects
pp ppπ + π p (p a ) p (p 1 ) p (p a ) p (p 1 ) C 1 π + (p 3 ) γ, IP, IR f, f π + (p 3 ) C π (p 4 ) γ, IP, IR π (p 4 ) p (p b ) p (p ) p (p b ) p (p ) The four-body process amplitude written in terms of two-body Regge amplitudes Lebiedowicz, Szczurek, Phys. Rev. D81 () 363.
pp ppπ + π The full Born amplitude of π + π production is a sum of continuum amplitude and the amplitudes through the s-channel resonances: M pp ppπ + π = Mππ continuum pp ppπ + π + M ππ resonances pp ppπ + π. (5) Absorption effects should be included in addition
Resonances Scalar/pseudoscalar resonances: P. Lebiedowicz, O. Nachtmann and A. Szczurek, Ann. Phys. 344C (14) 31. Tensor resonances: q 1 q IP µν IP κλ f ρσ P. Lebiedowicz, O. Nachtmann and A. Szczurek, Phys. Rev. D9 (16) 5415. For tensor meson and tensor pomerons there are 7 possible couplings. We have tried different of them. Only one (!) fits to experimental characteristics.
pp ppπ + π p (p a ) p (p 1 ) t 1 p (p a ) p (p 1 ) t 1 γ, IP, IR γ, IP, IR ˆt π + (p 3 ) π (p 4 ) γ, IP, IR γ, IP, IR û π (p 4 ) π + (p 3 ) t p (p b ) p (p ) t p (p b ) p (p ) The two (t- and u-channel) contributions must be added coherently. P. Lebiedowicz, O. Nachtmann and A. Szczurek, Phys. Rev. D9 (16) 5415.
pp ppπ + π The IPIP-exchange amplitude can be written as where M (IPIP π+ π ) = M (ˆt) λ aλ b λ 1 λ π + π + M (û) λ aλ b λ 1 λ π + π, (6) M (ˆt) λ aλ b λ 1 λ π + π 3β IPNN (p 1 + p a ) µ1 (p 1 + p a ) ν1 δ λ1 λ a F 1 (t 1 )F M (t 1 ) β IPππ (p t p 3 ) µ 1 (p t p 3 ) ν 1 1 4s 13 ( is 13 α IP) α IP(t 1 ) 1 [ˆF π (p t )] p t m π β IPππ (p 4 + p t ) µ (p 4 + p t ) ν 1 4s 4 ( is 4 α IP) α IP(t ) 1 3β IPNN (p + p b ) µ (p + p b ) ν δ λ λ b F 1 (t )F M (t ), (7) M (û) λ aλ b λ 1 λ π + π 3β IPNN (p 1 + p a ) µ1 (p 1 + p a ) ν1 δ λ1 λ a F 1 (t 1 )F M (t 1 ) β IPππ (p 4 + p u ) µ 1 (p 4 + p u ) ν 1 1 4s 14 ( is 14 α IP) α IP(t 1 ) 1 [ˆF π (p u )] p u m π β IPππ (p u p 3 ) µ (p u p 3 ) ν 1 4s 3 ( is 3 α IP )α IP(t ) 1 3β IPNN (p + p b ) µ (p + p b ) ν δ λ λ b F 1 (t )F M (t ). (8)
pp ppπ + π dσ/dm ππ (µb/gev).1.8.6.4 - pp pp π + π s = GeV η < 1, η <, p >.15 GeV π ππ t, π.5 < -t 1, -t <.3 GeV ππ-continuum + f (98) + f (17) j = 1 3 4 ππ-continuum dσ/dm ππ (µb/gev) 1.8.6.4 pp pp π + π η < 1, η π - <, p ππ t, π.3 < -t 1, -t s = GeV >.15 GeV <.3 GeV...5 1 1.5 M ππ (GeV).5 1 1.5 M ππ (GeV) Interesting (negative) interference of f (98) and two-pion continuum.
pp ppπ + π (µb/gev) dσ/dm ππ 1.8.6.4 - p p pp π + π s = 1.96 TeV η < 1.3, y < 1, p >.4 GeV π ππ t, π CDF data..8 1 1. 1.4 1.6 1.8 M ππ (GeV) Not completely exclusive data (protons not measured).
pp ppπ + π (µb/gev) 4 3 pp pp π + π y <, p >. GeV π t, π CMS preliminary data - s = 7 TeV (µb/gev) 4 3 pp pp π + π y <, π p t, π >. GeV CMS preliminary data - s = 7 TeV dσ/dm ππ dσ/dm ππ.5 1 1.5 M ππ (GeV).5 1 1.5 M ππ (GeV) The parameters fixed to the CDF data. Warning: Preliminary CMS data
Photoproduction at HERA VDM (vector dominance model) mechanism: γ ρ [ω] ρ IP, f IR [a IR ] p p Can be inserted to pp collisions.
pp ppπ + π photon induced production of ρ resonances p (p a ) p (p 1 ) p (p a ) p (p 1 ) γ ρ [ω] ρ π + (p 3 ) IP, f IR [a IR ] ρ ρ [ω] π + (p 3 ) π (p 4 ) IP, f IR [a IR ] π (p 4 ) γ p (p b ) p (p ) p (p b ) p (p ) Dominant photoproduction mechanism in the π + π channel. P.Lebiedowicz, O. Nachtmann and A. Szczurek, Phys. Rev. D91 (15) 743.
HERA data p) (µb) σ (γp ρ 5 15 low energy data H1 93 ZEUS 9 ZEUS 93 ZEUS 94 set B set A 5 1 W γp total IP f IR (GeV) 3 No freedom for 4 pp ppρ processes.
pp ppπ + π (µb/gev) dσ/dm ππ 1 IP/IR-IP/IR pp pp π + π s = 7 TeV y <.5 π p >.1 GeV T, π - (µb/gev) dσ/dm ππ 1 IP/IR-IP/IR pp pp π + π s = 7 TeV η <.9 π p >.1 GeV T, π - -1 γ-ip/ir + IP/IR-γ -1 γ-ip/ir + IP/IR-γ -.5 1 1.5 M ππ (GeV) -.5 1 1.5 M ππ (GeV) with absorption effects included
pp ppπ + π photon induced diffractive continuum p (p a) p (p 1) p (p a) p (p 1) p (p a) p (p 1) π (p t) γ π + (p 3) π (p 4) π (p u) γ π (p 4) π + (p 3) γ π + (p 3) π (p 4) IP, f IR IP, f IR IP, f IR p (p b) p (p ) p (p b) p (p ) p (p b) p (p ) So-called Söding mechanism.
Interference effect (µb/gev) dσ/dm ππ 4 3 pp pp π + π s = 7 TeV total ρ (77) continuum interference - -.4.6.8 1 1. 1.4 M ππ (GeV) Modification of the spectral shape (skewdness).
pp ppk + K Purely diffractive resonance mechanisms: p (p a ) p (p 1 ) IP, IR IP, IR f, f K + (p 3 ) K (p 4 ) p (p b ) p (p ) P. Lebiedowicz, O. Nachtmann and A. Szczurek, arxiv:184.476, in print in Phys. Rev. D
pp ppk + K Purely diffractive continuum mechanism: p (p a ) p (p 1 ) t 1 p (p a ) p (p 1 ) t 1 IP, IR IP, IR ˆt K + (p 3 ) K (p 4 ) IP, IR IP, IR û K (p 4 ) K + (p 3 ) t p (p b ) p (p ) t p (p b ) p (p )
pp ppk + K Diffractive photoproduction resonance mechanism: p (p a ) p (p 1 ) p (p a ) p (p 1 ) γ φ φ K + (p 3 ) IP φ φ K + (p 3 ) K (p 4 ) IP K (p 4 ) γ p (p b ) p (p ) p (p b ) p (p )
pp ppk + K Diffractive photoproduction continuum mechanism: p (p a) p (p 1) p (p a) p (p 1) p (p a) p (p 1) K (p t) γ IP, IR K + (p 3) K (p 4) K (p u) γ IP, IR K (p 4) K + (p 3) γ IP, IR K + (p 3) K (p 4) p (p b) p (p ) p (p b) p (p ) p (p b) p (p )
Results for CMS (µb/gev) 1 s = 13 TeV, η, η <.5, p 3 4.17 GeV < p, p y,1,p t,3 t,4 >.1 GeV <.5 GeV y, (µb/gev) 1 pp pp π + π η <.5, p >.1 GeV π t, π - dσ/dm 34 1 dσ/dm ππ -1-3 -3 4 1 1. 1.4 1.6 1.8 M 34 (GeV) -4.5 1 1.5.5 3 M ππ (GeV) CMS rapidity acceptance
Resonance decomposition (µb/gev) dσ/dm 34 1 1 - + pp pp K K s = 13 TeV, η, η < 1. 3 4 total continuum f (98), f (15), f (17) f (17), f (155) 3 4 1 1. 1.4 1.6 1.8 M 34 (GeV) Really many resonances may participate. Parameters fixed by detailed knowledge of different reactions.
f (98) line shape (µb/gev) 8 s = 13 TeV, η, η < 1 3 4 f (98) only m f = 98 MeV = 99 MeV m f (µb/gev) 4 3 s = 13 TeV, η, η < 1 3 4 f (98) only m f = 98 MeV, Γ f = MeV dσ/dm 34 6 4 dσ/dm 34.9.95 1 1.5 1.1 M 34 (GeV).9.95 1 1.5 1.1 M 34 (GeV) left: Γ tot = 7 MeV right: Γ tot = MeV (Achasov-Shestakov) Different position of the peak in π + π and K + K channels. pp ppφ gives contribution at the same M K + K as pp ppf (98) (the first reaction can be smoking-gun for observing effects of gluon saturation)
Angular distribution in the KK rest frame (f (15) and f (17)) (µb) r.f. dσ/dcosθ 3.4.3. s = 13 TeV, η, η < 1., p 3 4 M 34 (1.45, 1.6) GeV total continuum f (155) f (15),p t,3 t,4 >.1 GeV (µb) r.f. dσ/dcosθ 3..15.1 s = 13 TeV, η, η < 1., p 3 4 M 34 (1.65, 1.75) GeV total continuum f (17),p t,3 t,4 >.1 GeV.1.5 1.5.5 1 r.f. cosθ 3 1.5.5 1 r.f. cosθ 3 Not too instructive! Too small range of rapidity? Can CMS measured such distributions?
Angular distribution in the KK rest frame (µb) r.f. dσ/dcosθ 3.1.1.8.6 s = 13 TeV, η, η <.5, p 3 4 M 34 (1.45, 1.6) GeV total continuum f (155) f (15),p t,3 t,4 >.1 GeV.4. 1.5.5 1 r.f. cosθ 3 CMS range of rapidities
Predictions for different experiments (µb/gev) 1 s =. TeV, η, η < 1 3 4 p, p >. GeV t,3 t,4.3 GeV < -t 1, <.3 GeV - π + π (µb/gev) 1 s = 1.96 TeV, CDF data - π + π η, η < 1.3, y < 1 3 4 34 p, p >.4 GeV t,3 t,4 (µb/gev) 1 s = 13 TeV < η, η < 4.5 3 - π + π p, p t,3 4 >. GeV t,4 dσ/dm 34 1 + - K K dσ/dm 34 1 + - K K dσ/dm 34 1 + - K K 3 3 4.8 1 1. 1.4 1.6 1.8 M 34 (GeV) 4.8 1 1. 1.4 1.6 1.8 M 34 (GeV) 3.8 1 1. 1.4 1.6 1.8 M 34 (GeV) Can one observe φ meson?
t t Glueball filter variable distribution dp t = q t,1 q t, = p t, p t,1, dp t = dp t. (9) ) (µb/gev) dσ/d(dp.1.1.8.6 + - pp pp K K, s = 13 TeV η, η < 1, p, p >.1 GeV 4 3 total t,3 t,4 M 34 (1.45, 1.6) GeV continuum f (15) f (155) ) (µb/gev) dσ/d(dp.8.6.4 + - pp pp K K, s = 13 TeV η, η < 1, p, p >.1 GeV 3 4 t,3 t,4 total M 34 (1.65, 1.75) GeV continuum f (17).4....4.6.8 1 (GeV) dp t..4.6.8 1 (GeV) dp t Some difference between continuum and resonances
pp ppπ + π π + π Double resonance production: p p p p IP, IR IP, IR σ σ σ π + π π + π IP, IR IP, IR ρ ρ ρ π + π π + π p p p p
pp ppπ + π π + π Single resonance production: p p p p IP, IR IP, IR f σ σ π + π π + π IP, IR IP, IR f ρ ρ π + π π + π p p p p Contribution to mechanism of diffractive production of resonances (f (17), f 1 (185), f (15), f (17), f (195)) Contribution to decays and branching fractions.
pp ppσσ The amplitude for this process can be written as the following sum: M (σ exchange) pp ppσσ = M (IPIP σσ) + M (IPf IR σσ) + M (firip σσ) + M (f IRf IR σσ) (). For instance, the IPIP-exchange amplitude can be written as M (IPIP σσ) = M (ˆt) λ aλ b λ 1 λ σσ + M(û) λ aλ b λ 1 λ σσ (11) with the ˆt- and û-channel amplitudes M (ˆt) λ aλ b λ 1 λ σσ = ( i)ū(p 1, λ 1 )iγ (IPpp) µ 1 ν 1 (p 1, p a)u(p a, λ a) i (IP) µ 1ν 1,α 1 β 1 (s 13, t 1 ) iγ (IPσσ) α 1 β 1 (p t, p 3 ) i (σ) (p t) iγ (IPσσ) α β (p 4, p t) i (IP) α β,µ ν (s 4, t ) ū(p, λ )iγ µ (IPpp) ν (p, p b )u(p b, λ b ), M (û) λ aλ b λ 1 λ σσ = ( i) ū(p 1, λ 1 )iγ (IPpp) µ 1 ν 1 (p 1, p a)u(p a, λ a) i (IP) µ 1ν 1,α 1 β 1 (s 14, t 1 ) iγ (IPσσ) α 1 β 1 (p 4, p u) i (σ) (p u) iγ (IPσσ) α β (p u, p 3 ) i (IP) α β,µ ν (s 3, t ) ū(p, λ )iγ µ (IPpp) ν (p, p b )u(p b, λ b ). (1) (13)
pp ppρ ρ We write the amplitude as M λaλ b λ 1 λ ρρ = ( ) ( ) ǫ (ρ) ρ 3 (λ 3 ) ǫ (ρ) ρ 4 (λ 4 ) M ρ 3 ρ 4 λ aλ b λ 1 λ ρρ, (14) where ǫ (ρ) ρ (λ) are the polarisation vectors of the ρ meson. M (ρ exchange) ρ 3ρ 4 λ aλ b λ 1 λ ρρ (p 1 + p a) µ1 (p 1 + p a) ν1 δ λ1 λ a F 1 (t 1 ) F M (t 1 ) j V ρ 3ρ 1 µ 1 ν 1 (s 13, t 1, p t, p 3 ) (ρ) ρ 1 ρ (p t) V ρ 4ρ µ ν (s 4, t, p t, p 4 ) hˆfρ(p t )i ff + V ρ 4ρ 1 µ 1 ν 1 (s 14, t 1, p u, p 4 ) ρ (ρ) 1 ρ (p u) V ρ 3ρ µ ν (s 3, t, p u, p 3 ) hˆfρ(p u)i (p + p b ) µ (p + p b ) ν δ λ λ b F 1 (t ) F M (t ), where V µνκλ reads as V µνκλ (s, t, k, k 1 ) =Γ () µνκλ (k 1, k ) 1» 3β IPNN a IPρρ ( isα IP 4s )α IP (t) 1 + 1 g fir pp M a f IR ρρ ( isα f ) α f (t) 1 IR IR Γ () µνκλ (k 1, k ) 1» 3β IPNN b IPρρ ( isα IP 4s )α IP (t) 1 + 1 M g fir pp b f IR ρρ ( isα f IR ) α f IR (t) 1. (15) (16)
σσ and ρ ρ production pp pp(σσ π+π-π+π-) pp pp(ρρ π+π-π+π-) IP and IR -4 4 - -3-3 -4 4 3-4 4 4 Y -4-4 - 4 - -1 - -3 4-1 3 3 - Y Y4 3 IP and IR reggeized s = GeV RY Y 4-1 pp pp(ρρ π+π-π+π-) IP and IR s = GeV RY Y 3 RY Y 4 s = GeV -4-4 - s = GeV Y4 4 - Y 3 - -4-4 - Y4
pp ppπ + π π + π p (p a ) p (p 1 ) p (p a ) p (p 1 ) IP, IR t 1 π + (p 3 ) IP, IR π + (p 3 ) IP, IR t 34 t 45 π (p 4 ) π + (p 5 ) ρ, σ π (p 4 ) π + (p 5 ) IP, IR t 56 t π (p 6 ) IP, IR π (p 6 ) p (p b ) p (p ) p (p b ) p (p ) Only the first type of diagrams was included R. Kycia, P. Lebiedowicz, A. Szczurek and J. Turnau, Phys. Rev. D95 (17) 94.
pp ppπ + π π + π M = 1 ( ) M{3456} + M {5436} + M {3654} + M {5634} + 1 ( ) M{4356} + M {4536} + M {6354} + M {6534} + 1 ( ) M{3465} + M {5463} + M {3645} + M {5643} (17) + 1 ( M{4365} + M {4563} + M {6345} + M {6543} ),
pp ppπ + π π + π M {3456} = A πp(s 13, t 1 ) Fπ(t 34) A ππ(s t 34 mπ 45, t 45 ) Fπ(t 56) A πp(s t 56 mπ 6, t ), (18) M {4356} = A πp(s 14, t 1 ) Fπ(t 43) A ππ(s t 43 mπ 35, t 35 ) Fπ(t 56) A πp(s t 56 mπ 6, t ), (19) M {3465} = A πp(s 13, t 1 ) Fπ(t 34) A ππ(s t 34 mπ 46, t 46 ) Fπ(t 65) A πp(s t 65 mπ 5, t ), () M {4365} = A πp(s 14, t 1 ) Fπ(t 43) A ππ(s t 43 mπ 36, t 36 ) Fπ(t 65) A πp(s t 65 mπ 5, t ). (1)
pp ppπ + π π + π The subprocess amplitudes with the Regge exchanges are given as A πp (s, t) = A ππ (s, t) = j=ip,f IR η j s C j πp j=ip,f IR η j s C j ππ ( s s ( s s ) αj (t) 1 F j πp(t), () ) αj (t) 1 F j ππ(t), (3) where the signature factors are η IP = i and η fir = i.86.
pp ppπ + π π + π dσ [nb/gev] dm 4π 5 4 3 s = 7TeV, ATLAS triple-regge σ 1 1 3 5 15 5 3 M 4π [GeV] Large 4π invariant masses Good measurement for CMS (!) ALICE has too narrow range of rapidities and cannot see it.
pp ppφφ Observed by WA, no theoretical interpretation Two mechanisms possible a priori continuum ("φ" exchange, reggeization (?) ) f (195) (not yet, TTT structure) glueball candidate(s), below (f (17)) and above threshold Let us start exploration, preliminary results below
pp ppφφ, WA data Not yet perfect t (nb/gev) dσ/dm φφ 1 8 6 4 pp pp φφ s = 9.1 GeV WA data φ exchange φ exchange, reggeized Λ off,e = 1.45 GeV ) (nb/gev) dσ/d(dp 15 5 pp pp φφ WA data s = 9.1 GeV φ exchange, reggeized = 1.45 GeV Λ off,e.5 3 3.5 4 M φφ (GeV)..4.6.8 1 dp t (GeV) (nb) pp dσ/dφ 4 3 pp pp φφ WA data s = 9.1 GeV φ exchange, reggeized = 1.45 GeV Λ off,e dσ/d t (nb/gev ) 5 15 pp pp φφ WA data s = 9.1 GeV φ exchange, reggeized = 1.45 GeV Λ off,e 5 5 15 φ (deg) pp..4.6.8 1 t (GeV )
pp ppφφ, predictions for the LHC pp pp(φφ K K K s = 13 TeV η <.5 p (µb) 1 K + - + - K ) >.1 GeV t,k pp pp(φφ K K K s = 13 TeV η <.5 p (µb) 1 K + - - K ) reggeized >.1 GeV + t,k pp pp(φφ K K K s = 13 TeV η <.5 p (µb) 1 K + - - K ) reggeiz >. GeV + t,k dσ/dy 3 dy 4 3 dσ/dy 3 dy 4 3 dσ/dy 3 dy 4 3 4 4 4 Y 3 Y 4 Y 3 Y 4 Y 3
pp ppp p, predictions for the LHC (µb/gev) dσ/dm 4π 1 - - pp pp π + π π + π s = 13 TeV η π <.5, p >.1 GeV t,π η π <.5, p >. GeV t,π η π < 1, p >.1 GeV t,π < η π < 4.5, p >. GeV t,π (µb/gev) dσ/dm 4K 1 3 + - + - pp pp K K K K s = 13 TeV η <.5, p >.1 GeV K t,k η <.5, p >. GeV K t,k η < 1, p >.1 GeV K t,k < η < 4.5, p >. GeV K t,k 1 4 1 3 4 M 4π (GeV) 5.5 3 3.5 4 M 4K (GeV)
pp ppp p, predictions for the LHC (µb) dσ/dy diff 1 - - pp pp π + π π + π s = 13 TeV η π <.5, p >.1 GeV t,π η π <.5, p >. GeV t,π η π < 1, p >.1 GeV t,π < η π < 4.5, p >. GeV t,π (µb) dσ/dy diff 1 3 + - + - pp pp K K K K s = 13 TeV η <.5, p >.1 GeV K t,k η <.5, p >. GeV K t,k η < 1, p >.1 GeV K t,k < η < 4.5, p >. GeV K t,k 1 4 5 3 4 4 Y diff = Y 3 - Y 4 6 4 4 Y diff = Y 3 - Y 4 One should return to the topic once the data at the LHC are available CMS and LHCb data analysis in progress
pp ppp p The continuum (nonresonance) contribution p (p a ) p (p 1 ) t 1 p (p a ) p (p 1 ) t 1 γ, IP, IR γ, IP, IR ˆt p(p 3 ) p(p 4 ) γ, IP, IR γ, IP, IR û p(p 4 ) p(p 3 ) t p (p b ) p (p ) t p (p b ) p (p ) We do Feynman-diagram calculations with well fixed rules (!)
pp ppp p The full amplitude for p p production is a sum of continuum amplitude and the amplitudes with the s-channel resonances: M pp pp pp = M p p continuum pp pp pp + M p p resonances pp pp pp. (4) No p p resonances are known (to us) except of η c and χ c () mesons (see PDG).
pp ppp p M (IPIP pp) λ aλ b λ 1 λ λ 3 λ 4 = ( i)ū(p 1, λ 1 )iγ µ (IPpp) 1 ν 1 (p 1, p a )u(p a, λ a ) i (IP) µ 1ν 1,α 1 β 1 (s 13, t 1 ) ū(p 4, λ 4 )[iγ (IPpp) α β (p 4, p t ) i (p) (p t )iγ (IPpp) α 1 β 1 (p t, p 3 ) + iγ (IPpp) α 1 β 1 (p 4, p u ) i (p) (p u )iγ (IPpp) α β (p u, p 3 )]v(p 3, λ 3 ) i (IP) α β,µ ν (s 4, t ) ū(p, λ )iγ (IPpp) µ ν (p, p b )u(p b, λ b ). No absorption effects. (5)
pp ppp p (µb) dσ/dy 3 3 1-1 s = 13 TeV, no absorption - pp pp π + π + - pp pp K K pp pp pp - - -5 5 y 3 (µb) dσ/dy diff 5 4 3 1-1 - -3-4 s = 13 TeV, no absorption - pp pp π + π + - pp pp K K pp pp pp -6-4 - 4 6 y = y diff 3 - y 4 Surprising effect of the dip at y diff =. New effect for spin-1/ particles Good separation of t and u contributions.
y 3 xy 4 space pp pp π + π s = 13 TeV - pp pp pp s = 13 TeV (µb) 4 (µb) dy 3 1 σ/dy -1 d - 4 dy 3 1 σ/dy -1 d - -3 y 3 5-5 - - -5 5 y 4-3 y 3 5-5 - - -5 5 y 4 Completely different character. The dip is everywhere on the diagonal (ATLAS can do it, ALICE not really).
M p p -distribution (µb/gev) dσ/dm 34 3 1 s = 13 TeV, no absorption - pp pp π + π + - pp pp K K pp pp pp (µb/gev) dσ/dm 34 3 1 s = 13 TeV, no absorption - pp pp π + π + - pp pp K K pp pp pp y, y <.5 3 4-1 -1 - - -3 4 6 8 (GeV) M 34-3 4 6 8 (GeV) M 34 Different slope for pairs of pseudoscalar and for spin-1/ hadrons. We explicitly include spin degrees of freedom in the Regge calculus.
Role of subleading reggeons (µb) dσ/dy 3 3 pp pp pp s = 13 TeV Λ off,e = 1 GeV IP exchange IP, f & a IR exchanges IR (µb) dσ/dy diff 3 pp pp pp s = 13 TeV Λ off,e = 1 GeV IP exchange IP, f & a IR exchanges IR 1 1-1 -1 - - -5 5 y 3 - -4-4 y = y diff 3 - y 4 Even at s = 13 TeV a sizeable effect of subleading reggeons.
M p p xy diff pp pp pp s = 13 TeV (µb/gev) diff σ/dm 34 dy d M 34 1-1 - (GeV) 5 5 y diff -5 Region inside of the ridge seems promissing in searches for resonances
π + π versus p p production (GeV) M 34 8 6 - pp pp π + π s = 13 TeV, d σ/dm 34 dy (µb/gev) diff 1 (GeV) M 34 pp pp pp s = 13 TeV, d σ/dm 34 dy (µb/gev) diff 8 6 1 4-1 4-1 - - -4-4 y diff -3-4 - 4 y diff -3 Different situation for π + π and p p
Potential role of resonances with M GeV (µb) dσ/dy diff.5.4.3 s = 13 TeV, no absorption pp pp pp, Λ off,e =.8 GeV η, η <.5 3 4 p, p >.1 GeV t,3 t,4 total continuum f ()..1-4 - 4 y = y - y diff 3 4 resonances may distroy the dip
Potential role of resonances with M GeV (GeV) M 34 pp pp pp s = 13 TeV, d σ/dm 34 dy 3.5 3 diff (µb/gev) 1-1.5-1.5 η, η <.5 3 4 p, p >.1 GeV t,3 t,4 - -1 1 y diff -3-4 resonances may distroy (close) the gorge
Role of ingredients, ratios 3 η pp pp pp s = 13 TeV R 6 (IP + IR) (η 3, η ) 4 3 η pp pp pp s = 13 TeV R 6 (IP + IR + O) (η 3, η ) 4 1.1 4 LHCb 1.8 1.6 4 LHCb 1.5 1 4 ATLAS 1.4 1. 4 ATLAS.995 6 6 4 4 6 η 4 1 6 6 4 4 6 η 4.99 first: role of subleading reggeons second: role of odderon
Asymmetry between central p and p In two dimensions (e.g. η 1 η ) we can define the asymmetry: Ã () (η,η ) = d σ dη 3 dη 4 (η,η ) d σ dη 3 dη 4 (η,η) d σ dη 3 dη 4 (η,η ) + d σ dη 3 dη 4 (η,η). (6)
Asymmetry between central p and p A = σ(p) σ( p) σ(p) + σ( p) (7) η pp pp pp s = 13 TeV 6 A ~ () (η, η ).15 4.1 LHCb.5 4 ATLAS.5.1 6 6 4 4 6 η.15 Clear asymmetry
Asymmetry between central p and p Projection on one-dimension (full phase space) (η) A pp..1 pp pp pp, s = 13 TeV Λ off,e = 1 GeV -.1 -. -5 5 η
Asymmetry between central p and p Projection on one-dimension (experimental cuts) (η) A pp..1 pp pp pp, s = 13 TeV ATLAS kinematics Λ off,e = 1 GeV (η) A pp.1.5 pp pp pp, s = 13 TeV LHCb kinematics Λ off,e = 1 GeV.1 -.5. 1 1 η -.1.5 3 3.5 4 4.5 η
Conclusions, pp pph + h The Regge phenomenology was extended in practice to 3, 4 and 6 exclusive processes. The tensor pomeron/reggeon model was applied to many reactions. At lower energies tensor/vector reggeons. The dipion invariant mass has a rich structure which strongly depends on kinematical cuts (continuum, resonances, interference). Disagreement with CMS data due to large dissociation contribution. Purely exclusive data expected from STAR, CMS+TOTEM and ATLAS+ALFA.
Conclusions, pp pph + h K + K has also rich invariant mass structure (resonances). Predictions have been done. Some ambiguities in predictions. Search for glueballs requires partial wave analyses and observations in different final states. Four-pion production is also interesting. Double resonances, three-pomeron continuum. Search for single resonances (f (17)). φφ (K + K K + K ) final state at s = 9.1 GeV has been approximately described including continuum contribution. Predictions for LHC were shown. Resonances (glueballs) should be added. p p production has quite different characteristics (dσ/dm and dσ/dy diff (dip)). These are predictions of our approach.