Hunting for the Nucleon Resonances by Using Kaon Photoproduction

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1 Hunting for the Nucleon Resonances by Using Kaon Photoproduction T. Mart Departemen Fisika FMIPA, Universitas Indonesia, Depok 16424, Indonesia Indonesian Academy of Sciences, Jakarta, Indonesia Hadron and Nuclear Physics in 2017 KEK Tsukuba, January 2017 Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 1 / 49

2 Contents Principles of Resonance Modeling Kaon Photoproduction Multipoles Model Second peak in γp K Λ total CS: D 13 (1895) or P 13 (1900)? Searching for the Narrow Resonance Recent Progress in the Isobar Model Summary Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 2 / 49

3 Principles of Resonance Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 3 / 49

4 Principles of Resonance swissharmony.com Energy is transferred (via the wave) Only the fork with a same frequency (energy) will resonate Energy is absorbed by the resonating fork Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 4 / 49

5 Principles of Resonance Change the source fork with a multi-frequency source (e.g., loudspeaker) Scan from the lowest to the highest frequencies absorbed energy ω R frequency Energy is strongly absorbed at the resonating frequency ω = ω R Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 5 / 49

6 Hydrogen atom and proton can be excited γ γ d r e gluon gluon p u gluon u Bohr: hydrogen proton r = 4πε 0 h 2 mze 2 n 2, E = mz 2 e 4 32π 2 ε 2 0 h 2 1 n 2 = 13.6 n 2 ev. Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 6 / 49

7 Hydrogen atom and proton can be excited Excited states = resonance states resonance states γ e.s. 3.4 ev γ γ J π _3 0 N (1520) 2 γ π π 0 N (1520) g.s. hydrogen atom 13.6 ev _1 2 proton p (938) p p Instead of emitting a photon, due to the high energy, an excited proton (a nucleon resonance) can emit a meson (e.g., π). Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 7 / 49

8 Hydrogen atom and proton can be excited Hydrogen E (ev) 0 N* M (MeV) 3000 M (MeV) E = / n 2 ev g.s. 14 p 1000 p Particle Data Group 1000 Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 8 / 49

9 However, Quark Model predicts more resonances Particle Data Book Quark Model M (MeV) Most of the resonances predicted by quark models are not (yet) observed or listed in the Particle Data Book missing resonances p 1000 p 1000 WHY? PDB: Patrignani et al., Chin. Phys. C 40, (2016) QM: Capstick and Roberts, Phys. Rev. D 58, (1998) Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 9 / 49

10 Probably because the strangeness channel was excluded. Non Strangeness Channel π π π γ π N* = N* N* N N N N N Strangeness Channel K K K γ K N* = N* N* Λ Λ Λ N Λ. Kaon-hyperon scattering, kaon photoproduction Λ-hyperon replaces N to conserve the strangeness quantum numbers Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 10 / 49

11 Excitation of the proton Quantum mechanics probability p γ K Λ = γ p K γ K γ K γ K * p,n* K, K, K1 Λ p Λ p Λ p Λ Λ, Σ 0 (a) (b) (c) (d) All possible excitations should be taken into account we have to model the process Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 11 / 49

12 Modeling Kaon Photoproduction Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 12 / 49

13 Elementary Operator for Kaon-Maid Constructed from suitable tree-level Feynman diagrams (Covariant Isobar Model) Born p K,K *,K Λ, Σ 0 Resonance S (1650) 11 P 11(1710) P 13(1720) D (1895) 13 γ p γ K p Λ K γ K γ K γ p,n* * K, K, K1 K Λ p Λ p Λ p Λ Λ, Σ 0 (a) (b) (c) (d) = requires some information on hadronic coupling constants fitted to exp. data (except Born s ones) number of participating resonances some constraints gauge method (to preserve gauge invariance) Haberzettl s Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 13 / 49

14 First indication of missing resonance New 1998 SAPHIR data reveals a missing resonance D 13 (1895) TM and C. Bennhold, Physical Review C 61, (R) (2000) γ p K Λ old data σ tot (µb) W (GeV) Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 14 / 49

15 First indication of missing resonance New 1998 SAPHIR data reveals a missing resonance D 13 (1895) TM and C. Bennhold, Physical Review C 61, (R) (2000) γ p K Λ old data with some N* σ tot (µb) W (GeV) Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 14 / 49

16 First indication of missing resonance New 1998 SAPHIR data reveals a missing resonance D 13 (1895) TM and C. Bennhold, Physical Review C 61, (R) (2000) γ p K Λ old data with some N* SAPHIR 1998 data σ tot (µb) W (GeV) Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 14 / 49

17 First indication of missing resonance New 1998 SAPHIR data reveals a missing resonance D 13 (1895) TM and C. Bennhold, Physical Review C 61, (R) (2000) old data γ p K Λ with some N* SAPHIR 1998 data with some N* D 13 (1895) σ tot (µb) W (GeV) Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 14 / 49

18 Why do we believe this missing resonance? Comparison between the results from our fit to the Quark Model (QM) Missing Resonance Model m N Γ N ΓN NγΓ N KΛ/Γ N (MeV) (MeV) (10 3 ) Fit ± S 11 (1945) QM ± Fit ± P 11 (1975) QM ± Fit D 13 (1960) QM ± Fit P 13 (1950) QM ± 70 QM = S. Capstick and W. Roberts, Phys. Rev. D 58, (1998). Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 15 / 49

19 First indication of the missing resonance in K Λ channel TM and C. Bennhold, Physical Review C 61, (R) (1999) Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 16 / 49

20 And we are very happy... Particle Data Book : Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 17 / 49

First model available online, Kaon-Maid http://www.kph.uni-mainz.de/maid/kaon/kaonmaid.

21 First model available online, Kaon-Maid Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 18 / 49

22 Multipoles Model Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 19 / 49

23 Resonance terms using multipoles Remember the model for kaon photoproduction: p γ K Λ = γ p K γ K γ K γ K * p,n* K, K, K1 Λ p Λ p Λ p Λ Λ, Σ 0 (a) (b) (c) (d) There are a lot of N! with the complexity (in the covariant model) increases as their spin increases Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 20 / 49

24 Resonance terms using multipoles Instead of using a fully covariant formalism, the resonance term can be also parameterized by using the multipoles amplitude (Breit-Wigner form): E 0 (W ) = Ē0 c KΛ f γr (W )Γ tot (W )m R f KR (W ) m 2 R W 2 im R Γ tot (W ) e iφ E 0 Γ tot The advantage: Simple and does not generate unnecessary additional background term as in the case of the covariant calculation TM and Sulaksono, Phys. Rev. C 74, (2006) W=m R W Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 21 / 49

25 Try to use all nucleon resonances 15 Resonances up to l = 4 with the corresponding properties from the Review of Particle Physics. Resonance M R Γ R β K A 1/2 (p) A 3/2 (p) Overall Status (MeV) (MeV) (10 3 GeV 1/2 ) (10 3 GeV 1/2 ) status seen in KΛ S ± ± 16 - **** *** * - P ± 20 9 ± 22 - *** ** * - P ± ± 20 **** ** ± ** - D ± 13 2 ± 24 *** ** ± ± 8 17 ± 11 ** * D ± 8 15 ± 9 **** * ** * F ± ± 12 **** ** * F ± ± 60 ** * G **** * G **** - Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 22 / 49

26 Relation to the CGLN amplitudes Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 23 / 49

27 Relation to the Observables G. Knöchlein, D. Drechsel, and L. Tiator, Z. Phys. A 352, 327 (1995) Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 24 / 49

28 Experimental Data 3 data sets Experimental data sets used in the analysis (indicated by ). Other data are only used for comparison. Name Observable Symbol N Fit 1 Fit 2 Fit 3 SAPHIR 2004 Differential cross section dσ/dω Recoil polarization P 30 - CLAS 2006 Total cross section σ tot Differential cross section dσ/dω Recoil polarization P LEPS 2006 Total cross section σ tot Differential cross section dσ/dω 54 Photon asymmetry Σ 30 OLD Target asymmetry T Total cross section σ tot Total data Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 25 / 49

29 Differential Cross Sections Fit 1, Fit 2, Fit 3 dσ / dω (µb/sr) 0.3 cos θ = 0.80 p ( γ, K ) Λ cos θ = 0.70 cos θ = 0.60 cos θ = 0.50 cos θ = 0.40 cos θ = cos θ = 0 cos θ = cos θ = 0 cos θ = cos θ = 0 cos θ = cos θ = 0.40 cos θ = cos θ = 0.60 cos θ = cos θ = 0.80 cos θ = W (GeV) W (GeV) dσ / dω (µb/sr) p ( γ, K ) Λ cos θ = 0.95 cos θ = cos θ = 0.75 cos θ = cos θ = 0.55 cos θ = cos θ = 0.35 cos θ = cos θ = 5 cos θ = cos θ = 5 cos θ = cos θ = 5 cos θ = cos θ = 0.45 cos θ = cos θ = 0.65 cos θ = cos θ = 0.85 cos θ = W (GeV) W (GeV) Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 26 / 49

30 Problems of data consistency 3.5 p ( γ, K ) Λ σ tot (µb) TM and A.Sulaksono, PRC74, (2006) SAPHIR 1998 SAPHIR 2004 CLAS 2006 Fit 1 Fit 2 Fit W (GeV) Fitting all data democratic model which is not consistent with both data sets This problem is simply forgotten, but seems to appear mildly in the new Crystal Ball data Unsolved homework! Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 27 / 49

31 Which resonances are important? Define: χ 2 = χ2 All χ2 All N χall 2 100% Larger is More Important Different data sets need different resonances All data sets require the D 13 (2080), whereas the P 11 (1710) is less significant S 11 (1650) S 11 (2090) P 11 (1710) P 11 (2100) P 13 (1720) P 13 (1900) D 13 (1700) D 13 (2080) D 15 (1675) D 15 (2200) F 15 (1680) F 15 (2000) F 17 (1990) G 17 (2190) G 19 (2250) χ 2 (%) Fit 1 Fit 2 Fit Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 28 / 49

32 Second peak in γp K Λ total CS D 13 (1895) or P 13 (1900)? Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 29 / 49

33 Two models: with D 13 (1895) or P 13 (1900) Note: D 13 (1895) originates from D 13 (2080) Parameters of the two resonances obtained from fitting to the kaon photoproduction data in models A and B Parameter A B m D13 (2080) (MeV) Γ D13 (2080) (MeV) G (1) D 13 (2080) G (2) D 13 (2080) m P13 (1900) (MeV) Γ P13 (1900) (MeV) G (1) P 13 (1900) G (2) P 13 (1900) N data χ 2 /N dof σ tot (µb) Model B Model A Kaon-Maid CLAS 2006 p ( γ, K ) Λ W (GeV) Model A is better Bold face means fixed Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 30 / 49

34 P 13 (1900) and second peak σ tot (µb) σ tot (µb) Total Background S 11 (1650) D 13 (1700) P 11 (1710) P 13 (1720) P 11 (1840) P 13 (1900) D 13 (2080) S 11 (2090) P 11 (2100) CLAS 2006 Model A Model B W (GeV) in both models contribution of P 13 (1900) is dominant in the second peak second peak P 13 (1900) and not D 13 (1895) thus, we agree with... Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 31 / 49

35 PDG moves the particle to D 13 (1895) Particle Data Book now: Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 32 / 49

36 Origin of the second peak Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 33 / 49

37 Searching for the Narrow Resonance Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 34 / 49

38 Is there a pentaquark Θ? Predicted by: Diakonov, Petrov, Polyakov, Z. Phys. A 359, 305 (1997) Θ (1530) 1 N (1710) S 0 Σ (1890) Ξ 3/2 (2070) I3 first observed by: T. Nakano et al., Phys. Rev. Lett. 91, (2003) Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 35 / 49

39 How to produce pentaquark Θ photoproduction γ µ n n γ v e, µ p p n p g KΘN Θ g KΘN K 0 K Θ γ g e, µ Θ KΘN n p Θ K Θ γ K 0 g KΘ N Θ e, µ Θ Θ γ n p e g KΘN K K K *0, K 1 Θ γ K 0 V,T g K* ΘN Θ γ n g K * Kγ g V,T K* ΘN K K *, K 1 Θ. similar to kaon photoproduction change the coupling constants predict the cross section very small dσ / dω (nb/sr) dσ / dω (nb/sr) γ n K Θ cos θ W (GeV) γ p K 60 0 Θ cos θ W (GeV) 4 Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 36 / 49

40 History of pentaquark Θ 2003 : Existence from very likely to certain 2004 : Evidence of existence is only fair 2005 : Evidence of existence is poor 2006 : Evidence is questioned 2008 : Part of the history of science! Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 37 / 49

41 How about its family? Diakonov, Petrov, Polyakov, Z. Phys. A 359, 305 (1997) 1 Θ (1530) Γ N(1710) πn 3 Arndt 0 N (1710) R.A. Arndt, et al., Phys. Rev. C 69, (2004) S 1 Σ (1890) Γ N(1710) ηn 8 Kuznetsov V. Kuznetsov et al., Phys. Lett. B 647, 23 (2007) 2 Ξ 3/2 (2070) Γ N(1710) KΛ 3??? I 3 3 Diakonov, Petrov, Phys. Rev. D 69, (2004) m N = 1647 to 1690 MeV Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 38 / 49

42 Add one diagram for N(1710) Remember the model for kaon photoproduction: p γ K Λ = γ p K γ K γ K γ K * p,n* K, K, K 1 Λ p Λ p Λ p Λ Λ, Σ 0 (a) (b) (c) (d) Put a narrow N, scan the mass and width, find the lowest χ 2 Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 39 / 49

43 Our result 0-5 χ Γ KΛ / Γ tot. = we find an indication at M = 1650 MeV quantum numbers are consistent, i.e., J p = 1/ W (MeV) Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 40 / 49

44 Our result Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 41 / 49

45 Just deleted this year... Particle Data Book : Example of the particle R.I.P. Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 42 / 49

46 Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 43 / 49

47 Recent Progress in the Isobar Model Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 44 / 49

48 Recent Progress Threshold Region: γp K Λ : Phys. Rev. C 82, (2010). γn K 0 Λ : Phys. Rev. C 83, (2011). γn KΣ (4 channels) : Phys. Rev. C 90, (2014). From threshold up to W 3 GeV Covariant γp K Λ : Phys. Rev. D 92, (2015). with S. Clymton and A. J. Arifi (now at Osaka) Covariant γnk Σ (4 channels) : in progress. with S. Clymton Multipoles γp K Λ : prepared for publication. with S. Sakinah Multipoles γn KΣ (4 channels) : submitted. with M. J. Kholili (now at KEK Sokendai) Multipoles γn K 0 Λ : in progress. with A. Rusli Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 45 / 49

49 Example of the recent progress in covariant model 0.6 p ( γ, K ) Λ dσ / dω (µb / sr) W = GeV ANL-Osaka Bonn-Gatchina Kaon-Maid Our Model θ K (deg) Covariant model with spins 1/2, 3/2, and 5/2 nucleon resonances T. M., S. Clymton and A. J. Arifi, Phys. Rev. D 92, (2015). Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 46 / 49

50 Example of recent progress, more kinematics dσ / dω (µb / sr) p ( γ, K ) Λ θ (deg) Covariant model with spins 1/2, 3/2, and 5/2 nucleon resonances With 7500 data points we obtained χ 2 /N dof = T. M., S. Clymton and A. J. Arifi, Phys. Rev. D 92, (2015). Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 47 / 49

51 Note A number of slides in the followings are deleted due to the preliminary result Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 48 / 49

52 Summary Kaon photoproduction provides a complimentary tool for investigating nucleon resonances Two models: covariant and multipoles (complimentary) Multipoles model is simpler and more practical Problem with the N(1710)P 11 resonance: our finding less important In view of new data the N(1650)S 11, N(1720)P 13, and N(1900)P 13 are the important once **** status in KΛ Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 49 / 49

53 THANK YOU FOR YOUR PATIENCE Terry Mart (Universitas Indonesia) Nucleon Resonances KEK-HN-2017 Tuskuba 50 / 49

arxiv: v1 [nucl-th] 14 Aug 2012

arxiv: v1 [nucl-th] 14 Aug 2012 Origin of the second peak in the cross section of the K + Λ photoproduction T. Mart and M. J. Kholili Departemen Fisika, FMIPA, Universitas Indonesia, Depok 16424, Indonesia (Dated: May 24, 2018) arxiv:1208.2780v1