Prof. Dr. Drs. Terry Mart

No Title of Publication Journal Name Delete link
1 L. Syukurilla and T. Mart, Hadronic form factors in kaon photoproduction
AIP Conference Proceedings 1617 (2014) 126-129
2 S. Latifah, A. Sulaksono, and T. Mart, Boson star at finite temperature
Physical Review D90 (2014) 12, 127501
3 T. Mart, Electromagnetic production of KΣ on the nucleon near threshold
Physical Review C90 (2014) 6, 065202
4 L. Syukurilla and T. Mart, A combination of hadronic form factors for modeling the kaon photoproduction process γp→K+Λ
International Journal of Modern Physics E24 (2015) 1550008
5 T.P. Djun, B. Soegijono, T. Mart, L.T. Handoko, Viscosities of Gluon Dominated QGP Model within Relativistic Non-Abelian Hydrodynamics
International Journal of Modern Physics A30 (2015) 14, 1550077
6 Kaon photoproduction on the nucleon: Contributions of kaon hyperon final states to the magnetic moment of the nucleonS. Sumowidagdo, T. MartPhysical Review C60:028201,1999DOI:10.1103/PhysRevC.60.028201
ABSTRACT: By using the Gerasimov-Drell-Hearn (GDH) sum rule and an isobaric model of kaon photoproduction, we calculate contributions of kaon-hyperon final states to the magnetic moment of the proton and the neutron. We find that the contributions are small. The approximation of sigma_{TT'} by sigma_{T} clearly overestimates the value of the GDH integral. We find a smaller upper bound for the contributions of kaon-hyperon final states to the proton's anomalous magnetic moment in kaon photoproduction, and a positive contribution for the square of the neutron's magnetic moment.
7 K0 Sigma+ photoproduction with SAPHIRC. Bennhold,S. Goers, J. Barth, W. Braun, R. Burgwinkel, J. Ernst, K.H. Glander, J. Hannappel, N. Jopen, H. Kalinowsky, U. Kirch, F. Klein, F.J. Klein, E. Klempt, A. Kozela, R. Lawall, Zhen-ping Li, J. Link, T. Mart, D. Menze, W. Neuerburg, M. Paganetti, E. Paul, H. van Pee, R. Plotzke, M. Schumacher, W.J. Schwille, F. Smend, J. Smyrski, H.N. Tran, M.Q. Tran, F. Wehnes, B. Wiegers, F.W. Wieland, J. WisskirchenNuclear Physics A639:209-212,1998DOI:10.1016/S0375-9474(98)00275-9
ABSTRACT: Preliminary results of the analysis of the reaction p(gamma,K0)Sigma+ are presented. We show the first measurement of the differential cross section and much improved data for the total cross section than previous data. The data are compared with model predictions from different isobar and quark models that give a good description of p(gamma,K+)Lambda and p(gamma,K+)Sigma0 data in the same energy range. Results of ChPT describe the data adequately at threshold while isobar models that include hadronic form factors reproduce the data at intermediate energies.
8 Polarization response functions in kaon electroproduction C. Bennhold, T. Mart, D. Kusno Proceedings of the ICTP Conference on Perspectives in Hadronic Physics, Trieste, Italy, 12-16 May 1997, pp. 154-163 Available from arXiv
ABSTRACT: The electroproduction of kaons on the nucleon is shown to be an ideal tool to extract electromagnetic form factors of strange mesons and hyperons. Longitudinal n(e,e'K0)Lambda cross sections are found to be sensitive to the K0 form factor, while sensitivity to the Lambda magnetic form factor can be seen in recoil-beam double polarization observables. The KK*\gamma transition form factor could be extracted by measuring transverse response functions in the K-Sigma channels.
9 Photoproduction of the hypertritonT. Mart, D. Kusno, C. Bennhold, L. Tiator, D. DrechselNuclear Physics A631:765C-770C,1998DOI:10.1016/S0375-9474(98)00106-7
ABSTRACT: In the framework of the impulse approximation we study the photoproduction of the hypertriton $^3_{\Lambda}$H by using realistic $^3$He wave functions obtained as solutions of Faddeev equations with the Reid soft-core potential for different $^3_{\Lambda}$H wave functions. We obtain relatively small cross sections of the order of 1 nb. We also find that the influence of Fermi motion is important, while the effect of different off-shell assumptions on the cross section is not too significant.
10 Strangeness photoproduction with the SAPHIR detector J. Barth, M. Bockhorst, W. Braun, R. Burgwinkel, K.H. Glander, S. Goers, J. Hannappel, N. Jopen, U. Kirch, F. Klein, F.J. Klein, D. Menze, W. Neuerburg, E. Paul, W.J. Schwille, M.Q. Tran, R. Wedemeyer, F. Wehnes, B. Wiegers, F.W. Wieland, J. Wisskirchen, J. Ernst, Henry G. Juengst, H. Kalinowsky, E. Klempt, J. Link, H. von Pee, R. Plotzke, M. Schumacher, F. Smend, T. Mart, C. Bennhold Proceedings of the 6th Conference on the Intersections of Particle and Nuclear Physics (CIPANP 97), Big Sky, MT, USA, 27 May - 2 Jun 1997, pp. 849-851 Available from arXiv
ABSTRACT: Statistically improved data of total cross sections and of angular distributions for differential cross sections and hyperon recoil polarizations of the reactions \gamma p --> K^+ \Lambda and \gamma p --> K^+ \Sigma^0 have been collected with the SAPHIR detector at photon energies between threshold and 2.0 GeV. Here total cross section data up to 1.5 GeV are presented. The opposite sign of \Lambda and \Sigma polarization and the change of sign between forward and backward direction could be confirmed by higher statistics. A steep threshold behaviour of the K^+ \Lambda total cross section is observed.
11 Kaon photoproduction on the nucleon: Status and future prospects C. Bennhold, T. Mart, D. Kusno Proceedings of the 4th CEBAF / INT Workshop on N* Physics, Seattle, WA, USA, 9-13 Sep 1996, pp. 166-176 Available from arXiv
ABSTRACT: Kaon photo- and electroproduction off the nucleon is investigated in the framework of an isobaric model up to energies of about 1 GeV above threshold for all six isospin channels. The hadronic coupling constants in the model are determined by fitting to the available experimental data. We give a brief status report on the state of these models and discuss problems to be attacked in the future. We include hadronic form factors and show that they are essential for a proper description of the dynamics even though their inclusion has to be done carefully in order to preserve gauge invariance. We also investigate the effects of the K0 electromagnetic form factors for two quark models on the longitudinal and transverse differential cross sections. It is found that only the reaction n(e,e'K0)\Lambda is sufficiently sensitive to extract the K0 form factor.
12 Contributions of strange quarks to the magnetic moment of the proton H.W. Hammer , D. Drechsel, T. Mart DOE-ER-40561-306, INT-96-00-159, MKPH-T-96-19, Jan 1997. 10pp. Available from arXiv
ABSTRACT: Using the Gerasimov-Drell-Hearn sum rule and experimental total cross sections for photoproduction of $\eta$, $K$ and $\phi$ mesons on the proton, we obtain upper bounds for the contribution of strange quarks to the anomalous magnetic moment of the proton, $|\kappa_{s}| \le 0.20 \kappa_{p}$. The proposed experiments to measure the spin-dependence of the absorption cross section are expected to lower these bounds considerably. The existing data on $\eta$ production and phenomenological models for $K$ production agree with a negative sign for $\kappa_{s}$.
13 Electromagnetic production of the hypertritonT. Mart, L. Tiator, D. Drechsel, C. BennholdNuclear Physics A640:235-258,1998DOI:10.1016/S0375-9474(98)00441-2
ABSTRACT: Kaon photoproduction on He3, gamma + He3 --> K+ + Hypertriton, is studied in the framework of the impulse approximation. Realistic He3 wave functions obtained as solutions of Faddeev equations with the Reid soft-core potential are used along with different Hypertriton wave functions. Results are compared for several elementary operator models, which can successfully describe the elementary kaon production off the proton up to a photon lab energy of k = 2.2 GeV. It is found that the corresponding cross sections are small, of the order of several nanobarns. It is also shown that the influence of Fermi motion is important, while the effect of different off-shell assumptions on the cross section is not too significant.
14 Kaon and hyperon form-factors in kaon electroproduction on the nucleonT. Mart and C. BennholdNuclear Physics A639:237-246,1998DOI:10.1016/S0375-9474(98)00279-6
ABSTRACT: The electromagnetic form factors of strange mesons and baryons are studied by means of kaon electroproduction on the nucleon. The response functions that are sensitive to the K0, Lambda, Sigma, and KK*\gamma transition form factors are systematically explored. The effects of these form factors on several response functions are discussed.
15 Kaon electromagnetic production on nucleiC. Bennhold, F.X. Lee, T. Mart, L.E. WrightNuclear Physics A639:227C-235C,1998DOI:10.1016/S0375-9474(98)00278-4 
ABSTRACT: The formation and excitation of hypernuclei through kaon photoproduction is reviewed. Basic features of the production process are emphasized. The possibility of extracting new information on hypernuclear structure and on the wave function of the bound $\Lambda$ is discussed. New results are presented for the quasifree production process $A(\gamma, K \Lambda)B$. Observables of this reaction are shown to be sensitive to the $\Lambda$-nucleus final state interaction.
16 Gauge invariant tree level photoproduction amplitudes with form-factorsH. Haberzettl, C. Bennhold, T. Mart, T. FeusterPhysical Review C58:40-44,1998DOI: 10.1103/PhysRevC.58.40 
ABSTRACT: We show how the gauge-invariance formulation given by Haberzettl is implemented in practice for photoproduction amplitudes at the tree level with form factors describing composite nucleons. We demonstrate that, in contrast to Ohta's gauge-invariance prescription, this formalism allows electric current contributions to be multiplied by a form factor, i.e., it does not require that they be treated like bare currents. While different in detail, this nevertheless lends support to previous ad hoc approaches which multiply the Born amplitudes by an overall form factor. Numerical results for kaon photoproduction off the nucleon are given. They show that the gauge procedure by Haberzettl leads to much improved $\chi^2$ values as compared to Ohta's prescription.
17 Measurement of gamma p --> K+ Lambda and gamma p --> K+ Sigma0 at photon energies up to 2-GeVM.Q. Tran, J. Barth, C. Bennhold, M. Bockhorst, W. Braun, A. Budzanowski, G. Burbach, R. Burgwinkel, J. Ernst, K.H. Glander, S. Goers, B. Guse, K.M. Haas, J. Hannappel, K. Heinloth, K. Honscheid, T. Jahnen, N. Jopen, Henry G. Juengst, H. Kalinowsky, U. Kirch, F.J. Klein, F. Klein, E. Klempt, D. Kostrewa, A. Kozela, R. Lawall, L. Lindemann, J. Link, J. Manns, T. Mart, D. Menze, H. Merkel, R. Merkel, W. Neuerburg, M. Paganetti, E. Paul, R. Plotzke, U. Schenk, J. Scholmann, I. Schulday, M. Schumacher, P. Schutz, W.J. Schwille, F. Smend, J. Smyrski, W. Speth, H.N. Tran, H. van Pee, W. Vogl, R. Wedemeyer, F. Wehnes, B. Wiegers, F.W. Wieland, J. Wisskirchen, A. WolfPhysics Letters B445:20-26,1998  DOI:10.1016/S0370-2693(98)01393-8   
ABSTRACT: Associated strangeness production in the reactions γp→K+Λ and γp→K+Σ0 was measured with the SAPHIR detector at the electron stretcher ring ELSA at Bonn. Data on total and differential cross sections and on hyperon polarizations are presented. The total cross section for Λ production shows a strong threshold enhancement whereas the Σ0 data have a maximum at about Eγ=1.45 GeV. Along with the angular decomposition of the differential cross section into polynomials, this suggests resonance production. However, the angular distributions of both hyperon polarizations vary only slightly with the photon energy. Λ and Σ0 polarizations show opposite signs and change sign over the angular range.
18 Recent progress in the photon- and electroproduction of kaons on the nucleon. T. Mart, C. Bennhold, H. Haberzettl PiN Newsletters14:123-132,1998
19 T. Mart and M.J. Kholili, Origin of the second peak in the cross section of the K+Lambda photoproduction
Physical Review C 86 (2012) 022201
20 T. Mart, Evidence of the Non-Strange Partner of Pentaquarkfrom the Elementary K+Lambda Photoproduction
Few-Body Systems 54 (2013) 311-315
21 A. Salam, T. Mart, and K. Miyagawa, Role of the K1 Meson in K0 Photoproduction offthe Deuteron
Few-Body Systems 54 (2013) 261-264
22 Nucleon resonances in kaon photoproduction C. Bennhold, T. Mart, A. Waluyo, H. Haberzettl, G. Penner, T. Feuster, U. Mosel Proceedings of the Workshop on Electron Nucleus Scattering, Marciana Marina, Isola d'Elba, Italy, 22-26 Jun 1998 Available from arXiv
ABSTRACT: Nucleon resonances are investigated through the electromagnetic production of K-mesons. We study the kaon photoproduction process at tree-level and compare to a recently developed unitary K-matrix approach. Employing hadronic form factors along with the proper gauge prescription yields suppression of the Born terms and leads a resonance dominated process for both K-Lambda and K-Sigma photoproduction. Using new SAPHIR data we find the K+-Lambda photoproduction to be dominated by the S11(1650) at threshold, with additional contributions from the P11(1710) and P13(1720) states. The K-Sigma channel couples to a cluster of Delta resonances around W = 1900 MeV. We briefly discuss some tantalizing evidence for a missing D13 resonance around 1900 MeV with a strong branching ratio into KLambda channel.
23 H. Haberzettl, C. Bennhold, T. Mart, T. Feuster, Gauge invariant meson photoproduction with extended nucleons
Proceedings of the 8th International Conference on the Structure of Baryons (BARYONS 98), Bonn, Germany, 22-26 Sep 1998, pp. 466-469 Available from arXiv
24 Kaon photoproduction with form-factors in a gauge invariant approach H. Haberzettl, C. Bennhold, T. Mart, T. Feuster Few Body Systems Supplement 10:515-518,1999 Available from arXiv
ABSTRACT: The general gauge-invariant photoproduction formalism given by Haberzettl is applied to kaon photoproduction off the nucleon at the tree level, with form factors describing composite nucleons. We demonstrate that, in contrast to Ohta's gauge-invariance prescription, this formalism allows electric current contributions to be multiplied by a form factor, i.e., they do not need to be treated like bare currents. Numerical results show that Haberzettl's gauge procedure, when compared to Ohta's, leads to much improved $\chi^2$ values. Moreover, predictions for the new Bonn SAPHIR data for $p(\gamma,K^+)\Lambda$ are given.
25 S Channel baryon resonances in strange particle photoproduction: A First glance at new data from the SAPHIR detectorJ. Barth, M. Bockhorst, W. Braun, R. Burgwinkel, S. Goers, J. Hannappel, K. Heinloth, H.P. Jakob, N. Joepen, U. Kirch, F.J. Klein, L. Lindemann, S. Marwinski, D. Menze, W. Neuerburg, E. Paul, J. Scholmann, W.J. Schwille, M.Q. Tran, R. Wedemeyer, F. Wehnes, B. Wiegers, F.W. Wieland, J. Wisskirchen, J. Ernst, Henry G. Juengst, H. Kalinowsky, E. Klempt, J. Link, R. Maschuw, H. von Pee, R. Ploetzke, C. Strassburger, K. Wittmack, F. Smend, M. Schumacher, T. Mart, M. Guidal, J.M. Laget, C. BennholdProceedings of the 7th International Conference on the Structure of Baryons (Baryons '95), Santa Fe, New Mexico, USA, 3-7 Oct 1995, pp. 417-420
26 The K0 form-factor in kaon electroproductionC. Bennhold, Hiroshi Ito, T. MartProceedings of the 7th International Conference on the Structure of Baryons, Santa Fe, N.Mex., 3-7 Oct 1995, pp. 323-326
27 Kaon photoproduction and electroproduction on nucleonsT. Mart and C. BennoldFew Body Systems Supplement 9:369-373,1995
28 Threshold Properties of the KLambda Photoproduction T. Mart American Institute of Physics Conference Proceedings 1325, 3-7 (2010)
29 Photo- and electroproduction of the $K^0\Lambda$ near threshold and effects of the $K^0$ electromagnetic form factorT. MartPhysical Review C83, 048203 (2011)
By extending our previous isobar model to the K^0Lambda isospin channel we investigate the properties of the K^0Lambda photo- and electroproduction at energies near threshold. It is found that the pseudovector (PV) coupling yields significantly larger cross section. Variation of the K_1 coupling constants has significant effect only on the PV model. The electromagnetic form factor of the neutral kaon K^0 is found to have a sizable effect on the longitudinal cross section of the K^0Lambda electroproduction near the threshold.
30 Evidence for the $J^p = 1/2^+$ narrow state at 1650 MeV in the photoproduction of KLambdaT. MartPhysical Review D83, 094015 (2011)
We have investigated the existence of the J^p=1/2^+ narrow resonance predicted by the chiral soliton model by utilizing the kaon photoproduction process gamma + p --> K^+ + Lambda. For this purpose we have constructed two phenomenological models based on our previous effective Lagrangian model, which are able to describe kaon photoproduction from threshold up to W = 1730 MeV. By varying the mass (width) of an inserted P_{11} resonance from 1620 to 1730 MeV (0.1 to 1 MeV and 1 to 10 MeV) a number of fits has been performed in order to search for the resonance mass. Our result indicates that the most promising candidate mass (width) of this resonance is 1650 MeV (5 MeV). Although our calculation does not exclude the possibility of narrow resonances with masses of 1680, 1700 and 1720 MeV, the mass of 1650 MeV is obtained for all phenomenological models used in this investigation. Variations of the resonance width and $K\Lambda$ branching ratio are found to have a mild effect on the chi^2. The possibility that th
31 Kaon Photo and Electroproduction Near Threshold T. Mart Talk given at Baryons'10: International Structure of Baryons, December 7-11, 2010, Osaka, Japan  
32 Are Hyperon Resonances Required in the Elementary K+Lambda Photoproduction?T. Mart and N. NurhadiansyahFew-Body Systems 2012DOI 10.1007/s00601-012-0497-9 We have investigated the role of hyperon resonances in the kaon photoproduction process, gamma p --> K+ Lambda , by using a covariant isobar model. To this end, new experimental data are used in the fitting process, whereas the old SAPHIR 1998 data are also used for comparison. The result indicates that the Lambda(1600)P01 and Lambda(1810)P01 hyperon resonances can significantly reduce the χ 2 and, simultaneously, can increase the hadronic form factor cut-off in the background terms. This finding is different from the result of the previous studies, which showed that the Lambda(1800)S01 was important for this purpose, instead of the Lambda(1600)P01.
33 Kaon photoproduction and electroproduction near thresholdAIP Conf.Proc. 1388 (2011) 273-279
We analyze the electromagnetic production of K^+Lambda and K^0Lambda near their production thresholds by using isobar models. In the K^+Lambda channel we show that the model can nicely describe the available experimental data. In the K^0Lambda channel we demonstrate that the K^0 charge form factor has sizable effects on the longitudinal cross section. By extending the model up to W = 1730 MeV, we are able to observe the existence of the narrow P_{11} (J^p = 1/2^+) resonance in the kaon photoproduction process. It is found that the most convincing mass (width) of this resonance is 1650 MeV (5 MeV).
34 Appropriate observables for investigating narrow resonances in kaon photoproduction off a protonT. MartAmerican Institute of Physics Conference Proceedings 1454 (2012) 19-22
The existence of non-strange partner of pentaquark, the Jp = 1/2+ narrow resonance, has been investigated by utilizing kaon photoproduction off a proton. It is found that the corresponding mass is 1650 MeV and the appropriate observables for investigating the existence of this resonance are the recoiled hyperon polarization, the beam-recoil double polarization Cx, and differential cross section at backward angles. Future kaon photoproduction experiments should focus on these observables.
35 Role of Resonances in the Electromagnetic Production of Kaon Near ThresholdT. MartEuropean Physical Journal Web of Conferences 20, 02007 (2012)
Kaon photo- and electroproduction processes near their production thresholds are investigated by using an effective Lagrangian method. It is found that the nucleon and hyperon resonances play a considerably important role in this kinematics. It is also found that kaon photoproduction off the proton may provide a new arena for investigating the existence of the narrow resonance predicted by the soliton models.
36 Electromagnetic production of hypernucleiB.I.S. van der Ventel, T. Mart, H.-F. Lu, H.L. Yadav, G.C. HillhouseAnnals of Physics 326 (2011) 1085 - 1106
ABSTRACT: A formalism for the electromagnetic production of hypernuclei is developed where the cross section is written as a contraction between a leptonic tensor and a hadronic tensor. The hadronic tensor is written in a model-independent way by expanding it in terms of a set of five nuclear structure functions. These structure functions are calculated by assuming that the virtual photon interacts with only one bound nucleon. We use the most recent model for the elementary current operator which gives a good description of the experimental data for the corresponding elementary process. The bound state wave functions for the bound nucleon and hyperon are calculated within a relativistic mean-field model. We calculate the unpolarized triple differential cross section for the hypernuclear production process e + 12C --> e + K+ + 12_Lambda{B} as a function of the kaon scattering angle. The nuclear structure functions are calculated within a particle-hole model. The cross section displays a characteristic form of
37 Progress and Issues in the Electromagnetic Production of Kaon on the NucleonT. MartInvited talk at Sendai International Symposium on Strangeness in Nuclear and Hadronic Systems (SENDAI 08), Sendai, Japan, 15-18 Dec 2008. Published in *Sendai 2008, Strangeness in nuclear and hadronic systems* 51-62 also published inInternational Journal of Modern Physics E 19, 2343-2354 (2010)arXiv:0904.3601 [nucl-th]
The present status of kaon photo- and electroproduction on the nucleon is briefly reviewed. Some current important issues in this field are discussed.
38 Electromagnetic production of kaons on the nucleonT. Mart, C. Bennhold, L. AlfieriActa Physica Polonica B27:3167-3170,1996Available from arXiv
ABSTRACT: Kaon photo- and electroproduction in all six isospin channels are investigated by means of an isobaric model. It is found that existing models can only partially describe the current experimental data. Moreover, the extracted coupling constants are mostly inconsistent with the prediction of SU(3) symmetry or the information from hadronic reactions. In order to further analyze this problem, we introduce a form factor at the hadronic vertices KNY (with Y = Lambda or Sigma) and study its behavior qualitatively. Our result suggests the need of more accurate experiments, especially in the charged $\Sigma$ and the neutral $K^0$ channels.
39 Recent Progress in Electromagnetic Production of Associated Strangeness on the NucleonT. MartInvited Review in: Jurnal Matematika & Sains Institute of Technology Bandung 12, 1-23 (2007)
ABSTRACT:
40 Electromagnetic Production of HypernucleiT. MartInvited Review in: Jurnal Matematika & Sains Institute of Technology Bandung 12, 49-62 (2007)
ABSTRACT:
41 MODEL-INDEPENDENT EXTRACTION OF THE KΛp COUPLING CONSTANT T. MartJurnal Makara 12, 89-96, 2008
ABSTRACT: We have extracted the kaon-hyperon-nucleon coupling constant by means of a model-independent method and recent experimental data on kaon photoproduction off a nucleon. The extracted coupling constant is consistent with the SU(3) prediction as well as with the values obtained from the kaon-nucleon scattering process.Keywords: Coupling constant, kaon, hyperon, electromagnetic production, strangeness
42 Numerical problem in computation of the hypertriton production cross sectionT. MartJournal of Theoretical and Computational Studies 8 (2008) 0403, 7 pages
ABSTRACT: We discuss the numerical problems in the calculation of the hypertriton electroproduction cross section. We found that the accuracy of the calculation could still be maintained if we used at least four lowest partial waves of the nuclear wave functions. We also present the cpu-times required to calculate the cross sections. We found that the cpu-time could be reduced by a factor of 60 if we used these specific partial waves, whereas the deviation of calculated cross section from the full calculation is less than 4i?1/2We conclude that in view of the present experimental error bars future investigations could just use these lowest partial waves.
43 Omori's law and the propagation of monetary crisis in the Southeast Asian countriesT. MartJournal of Theoretical and Computational Studies 7 (2007) 0401, 7 pages
ABSTRACT: We report on our analysis of the available historical currency exchange rates from 10 Southeast Asian countries. We use Omori's law to precisely locate the time position when these currencies started to collapse. The result of our analysis corroborates the finding of previous investigation by Lillo and Mantegna that the returns exceeding certain thresholds can be nicely described by a power law function analogous to the Omori's law. Furthermore, in contrast to common believe, we found that the monetary crisis in this region was not started in Thailand. We estimate that the sign of the monetary crisis had been previously alarmed by the Kyat (the Myanmar currency) two years before the crisis propagated to Thailand. The propagation of the crisis is found to be different from the results of previous studies.
44 Electromagnetic production of kaon near thresholdT. MartPhysical Review C82, 025209,2010doi:10.1103/PhysRevC.82.025209
Kaon photo- and electroproduction off a proton near the production threshold are investigated by utilizing an isobar model. The background amplitude of the model is constructed from Feynman diagrams, whereas the resonance term is calculated by using the multipole formalism. It is found that both pseudoscalar and pseudovector models can nicely describe the available photoproduction data up to W = 50 MeV above the threshold. The Lambda resonance S_{01}(1800) is found to play an important role in improving the model. In the case of double polarization observables Ox and Oz our result corroborates the finding of Sandorfi et al. Due to the large contributions of the K* and K1 vector mesons, extending the model to the case of electroproduction is almost impossible unless either special form factors that strongly suppress their contributions are introduced or all hadronic coupling constants are refitted to both photo- and electroproduction databases, simultaneously. It is also concluded that investigation of the kao
45 Strange-particle production via the weak interactionG.B. Adera, B.I.S. Van Der Ventel, D.D. van Niekerk, T. MartPhysical Review C82, 025501, 2010doi:10.1103/PhysRevC.82.025501
The differential cross sections for the neutrino-induced weak charged current production of strange particles in the threshold energy region are presented. The general representation of the weak hadronic current is newly developed in terms of eighteen unknown invariant amplitudes to parametrize the hadron vertex. The Born-term approximation is used for the numerical calculations in the framework of the Cabibbo theory and SU(3) symmetry. For unpolarized octet baryons four processes are investigated, whereas in the case of polarized baryons only one process is chosen to study the sensitivity of the differential cross section to the various polarizations of the initial-state nucleon and the final-state hyperon
46 Suppression of coupling constants in Sigma photoproductionT. Mart and C. BennholdNuclear Physcs A585:369C-370C,1995DOI:10.1016/0375-9474(94)00613-R 
47 Effects of the neutrino trapping on the low-density instability of multi-component matterT. Mart and A. SulaksonoModern Physics Letters A 24, 1059-1062, 2009DOI: 10.1142/S0217732309000590
ABSTRACT: The role of the Coulomb and isovector effects in dense stellar matter with neutrino trapping in the region of perturbative momentum q ≤ 0.6 fm-1 has been investigated. The result might have an impact on the neutrino transport in stellar matter.
48 Neutrino electromagnetic form-factors effect on the neutrino cross section in dense matterA. Sulaksono, C. Kalempouw-Williams, P.T.P. Hutauruk, T. MartPhysical Review C73:025803,2006DOI:10.1103/PhysRevC.73.025803
The sensitivity of the differential cross section of the interaction between a neutrino-electron and dense matter to the possibly nonzero neutrino electromagnetic properties has been investigated. Here, the relativistic mean field model inspired by effective field theory has been used to describe nonstrange dense matter, both with and without the neutrino trapping. We have found that the cross section becomes more sensitive to the constituent distribution of the matter, once electromagnetic properties of the neutrino are taken into account. The effects of neutrino electromagnetic properties on the cross section become more significant for the neutrino magnetic moment unu>10-10uB and for the neutrino charge radius R>10-5 MeV-1.
49 Relativistic mean field models at high densities A. Sulaksono, P.T.P. Hutauruk, C. Kalempouw-Williams, T. Mart Proceedings of the 3rd Asia Pacific Conference on Few-Body Problems in Physics (APFB05), Korat, Nakhon Ratchasima, Thailand, 26-30 Jul 2005.
The effect of vector-isovector terms predicted by relativistic mean field models based on effective field theory on the equation of state and the neutrino mean free path in neutron stars has been studied. Using a procedure similar to Horowitz and Piekarewicz in treating the isovector sector, a parameter set (G2*) that predicts a much smaller proton fraction than the standard one (G2) can be obtained. We found that G2* has a softer equation of state compared to G2 at higher densities and the regularity of the neutrino mean free path does not depend on the proton fraction.
50 Isobar model for photoproduction of K+Sigma0 and K0Sigma+ on the proton T. Mart Proceedings of the 3rd Asia Pacific Conference on Few-Body Problems in Physics (APFB05), Korat, Nakhon Ratchasima, Thailand, 26-30 Jul 2005
Kaon photoproductions on the proton gamma p ---> K+ Sigma0 and gamma p ---> K0Sigma+ have been simultaneously analyzed by using isobar models and new SAPHIR data. The result shows that isobar models such as KAON MAID require more resonances in order to explain the data.
51 Photoproduction of Theta+ on the nucleon and deuteron T. Mart, , A. Salam, K. Miyagawa, C. Bennhold Proceedings of the International Workshop on PENTAQUARK04, Spring-8, Hyogo, Japan, 20-23 Jul 2004, pp. 157-164 Available from arXiv database
Photoproduction of the pentaquark particle Theta^+ on the nucleon has been studied by using an isobar and a Regge model. Using the isobar model, total cross sections around 100 nb for the gamma n --> K- Theta+ channel and 400 nb for the gamma p --> {\bar K}0 Theta+ process are obtained. The inclusion of the K* intermediate state yields a substantially large effect, especially in the gamma p --> {\bar K}0 Theta+ process. The Regge approach predicts smaller cross sections, i.e., less than 100 nb (20 nb) for the process on the neutron (proton). By using an elementary operator from the isobar model, cross sections for the process on a deuteron are predicted.
52 Kaon photoproduction in the Feynman and Regge theories T. Mart and C. Bennhold Invited talk at International Workshop on Strangeness Nuclear Physics, Osaka, Japan, 29-31 Jul 2004 Available from arXiv database
Kaon photoproduction on the nucleon has been investigated in the isobar (Feynman) and Regge frameworks. Two possible combinations of the theories are discussed. Results are compared with present experimental data.
53 Rescattering effects and two-step process in kaon photoproduction on the deuteron A. Salam, K. Miyagawa, T. Mart, C. Bennhold, W. Gloeckle Talk given by A. Salam at International Workshop on Strangeness Nuclear Physics, Osaka, Japan, 29-31 Jul 2004 Available from arXiv database
Kaon photoproduction on the deuteron is investigated by considering YN and KN rescattering and the two-step process gamma d --> pi NN --> KYN. A strong enhancement in the total cross section is found from the two-step process. YN rescattering has remarkable effects in the inclusive and exclusive cross section, while the effect of KN rescattering is much less important.
54 Missing resonances in kaon photoproduction on the nucleon T. Mart, A. Sulaksono, C. Bennhold Proceedings of the International Symposium on Electrophoto Production of Strangeness on Nucleons and Nuclei (SENDAI 03), Sendai, Japan, 16-18 Jun 2003, pp. 65-74 Available from arXiv database
ABSTRACT: New kaon photoproduction data on a proton, gamma + p --> K+ + Lambda, are analyzed using a multipole approach. The background terms are given in terms of gauge invariant, crossing symmetric, Born diagrams with hadronic form factors, while the resonances are parameterized using Breit-Wigner forms. Preliminary results suggest a number of new resonances, as predicted by many quark model studies. A comparison between the extracted multipoles and those obtained from KAON-MAID is presented.
55 Extending isobar model for kaon photoproduction up to 16-GeV T. Mart and T. Wijaya Acta Physica Polonica B34:2651-2664,2003 Acta Physica Polonica Server
ABSTRACT: We extend the isobar model for kaon photoproduction to consider higher energy data by combining the model with a Regge approach. The extended model works nicely between threshold and 16 GeV. It is shown that model with crossing symmetric Born terms leads to a better description of experimental data. We use the model to calculate contributions of kaon channels to the Gerasimov--Drell--Hearn sum rule up to 16 GeV. PACS numbers: 13.60.Le, 11.55.Hx, 13.40.Em, 14.20.Dh
56 Kaon photoproduction and electroproduction on the deuteron with beam and recoil polarizations K. Miyagawa, T. Mart, C. Bennhold, Walter Gloeckle Proceedings of the International Symposium on Electromagnetic Interactions in Nuclear and Hadron Physics (EMI 2001), Osaka, Ibaraki, Japan, 4-7 Dec 2001, pp. 347-356
57 Differential cross section and photon beam asymmetry for the polarized-gamma n ---> K+ Sigma- reaction at E(gamma) = 1.5GeV-2.4GeVH. Kohri, D.S. Ahn, J.K. Ahn, H. Akimune, Y. Asano, W.C. Chang, S. Date, H. Ejiri, S. Fukui, H. Fujimura, M. Fujiwara, S. Hasegawa, K. Hicks, T. Hotta, K. Imai, T. Ishikawa, T. Iwata, H. Kawai, Z.Y. Kim, K. Kino, N. Kumagai, S. Makino, T. Mart, T. Matsuda, T. Matsumura, N. Matsuoka, T. Mibe, M. Miyabe, Y. Miyachi, M. Morita, N. Muramatsu, T. Nakano, M. Niiyama, M. Nomachi, Y. Ohashi, H. Ohkuma, T. Ooba, D.S. Oshuev, C. Rangacharyulu, A. Sakaguchi, T. Sasaki, P.M. Shagin, Y. Shiino, A. Shimizu, H. Shimizu, Y. Sugaya, M. Sumihama, Y. Toi, H. Toyokawa, A. Wakai, C.W. Wang, S.C. Wang, K. Yonehara, T. Yorita, M. Yoshimura, M. Yosoi, R.G.T. ZegersPhysical Review Letters 97:082003,2006 DOI:10.1103/PhysRevLett.97.082003
ABSTRACT: Differential cross sections and photon-beam asymmetries have been measured for the gamma-vector n-->K+Sigma- and gamma-vector p-->K+Sigma0 reactions separately using liquid deuterium and hydrogen targets with incident linearly polarized photon beams of Egamma=1.5-2.4 GeV at 0.6
58 Analysis of the data consistency on kaon photoproduction with Lambda in the final stateP. Bydzovsky and T. MartPhysical Review C76:065202,2007 DOI:10.1103/PhysRevC.76.065202
The recent CLAS 2005, SAPHIR 2003, LEPS, and the old, pre-1972, data on K+Lambda photoproduction are compared with theoretical calculations in the energy region of E_gamma^lab < 2.6 GeV in order to learn about their mutual consistency. The isobaric models Kaon-Maid and Saclay-Lyon, along with new fits to the CLAS data, are utilized in this analysis. The SAPHIR 2003 data are shown to be coherently shifted down with respect to the CLAS, LEPS, and pre-1972 data, especially at forward kaon angles. The CLAS, LEPS, and pre-1972 data in the forward hemisphere can be described satisfactorily by using the isobaric model without hadronic form factors. The inclusion of the hadronic form factors yields a strong suppression of the cross sections at small kaon angles and c.m. energies larger than 1.9 GeV, which is not observed in the existing experimental data. We demonstrate that the discrepancy between the CLAS and SAPHIR data has a significant impact on the predicted values of the mass and width of the "missing resonanc
59 Polarization observables in exclusive kaon photoproduction on the deuteronK. Miyagawa, T. Mart, C. Bennhold, W. GlocklePhysical Review C74:034002,2006DOI:10.1103/PhysRevC.74.034002
Single and double polarization observables for kaon photoproduction on the deuteron are studied theoretically with modern hyperon-nucleon forces. The kinematical region of the kaon scattered forward with large momentum is thoroughly investigated where either the quasifree scattering leading to the kaon and hyperon or the final-state interaction between hyperon and nucleon are expected. The quasifree scatterings show characteristic peaks in the inclusive cross sections. The final-state interaction effects are significant, especially around the LambdaN and SigmaN thresholds. The double polarization Cz is found to be sensitive to the final-state interaction effects. Precise data would help to clarify the property of the LambdaN-SigmaN interaction and also help to extract the information on the elementary amplitude from the quasifree scattering region.
60 Can we extract the pion electromagnetic form-factor from a t-channel diagram only? T. Mart Modern Physics Letters A23:3317-3329,2008 DOI: 10.1142/S0217732308027230
We show that we are able to extract the pion electromagnetic form factor by using the recent charged pion electroproduction data from JLab and a simple t-channel diagram. For this purpose we have performed the Q2-independent and dependent analyses. The result of the first analysis is in good agreement with those of previous works and fit the Maris and Tandy model as well as the monopole parametrization which describes a pion radius of 0.672 fm. The result of the second analysis corroborates the findings in the first analysis. Our findings therefore provide a direct proof that at the given kinematics the t-channel diagram really dominates the process. This could also set a new constraint to the phenomenological models that try to describe the process.
61 Instabilities of relativistic mean field models and the role of nonlinear termsA. Sulaksono, T. Mart, T.J. Burvenich, J.A. MaruhnPhysical Review C76:041301,2007 DOI: 10.1103/PhysRevC.76.041301
ABSTRACT: The instability of nuclear matter due to particle-hole excitation modes has been studied in the framework of several relativistic mean-field (RMF) models. It is found that both the longitudinal and the transversal modes depend sensitively on the parameter sets used. The important impact of the vector and vector-scalar nonlinear terms on the stability of both modes is demonstrated. Our finding corroborates the result of previous studies, namely that certain RMF models cannot be used in high-density applications. However, we show that for certain parameter sets of RMF models this shortcoming can be alleviated by adding these nonlinear terms.
62 Impact of the monetary crisis on statistical properties of the Jakarta and Kuala Lumpur stock exchange indicesT Mart and T AminotoPhysica A373:634-650,2007 DOI:10.1016/j.physa.2006.06.001
ABSTRACT: Using the tools developed for statistical physics, we simultaneously analyze statistical properties of the Jakarta and Kuala Lumpur Stock Exchange indices. In spite of the small number of the data used in the analysis, the result still shows the universal behavior of complex systems previously found in the leading stock indices. We also analyze their properties before and after the crash caused by the monetary crisis. To locate the time position when the crash started we use the Omori law. We found that after the crash both stocks do not show a same statistical behavior. The impact of currency controls is observed in the distribution of the index returns.
63 Multipole approach for photo and electroproduction of kaon T. Mart, A. Sulaksono Proceedings of the 9th International Conference on Hypernuclear and Strange Particle Physics (HYP 2006), Mainz, Germany, 10-14 Oct 2006. arXiv:nucl-th/0701007v1
ABSTRACT: We have analyzed the experimental data on K+Lambda photoproduction by using a multipole approach. In this analysis we use the background amplitudes constructed from appropriate Feynman diagrams in a gauge-invariant and crossing-symmetric fashion. Results of our analysis reveal the problem of mutual consistency between the new SAPHIR and CLAS data. We found that the problem could lead to different conclusions on ``missing resonances''. We have also extended our analysis to the finite Q2 region and compared the result with the corresponding electroproduction data.
64 Experimental results from SAPHIR at ELSA J. Barth, C. Bennhold, W. Braun, J. Ernst, K.H. Glander, S. Goers, J. Hannappel, N. Jopen, (Joepen, N.) H. Kalinowsky, F. Klein, E. Klempt, A. Kozela, R. Lawall, J. Link, T. Mart, D. Menze, W. Neuerburg, M. Ostrick, E. Paul, R. Plotzke, (Ploetzke, R.) I. Schulday, M. Schumacher, W.J. Schwille, F. Smend, J. Smyrski, H. van Pee, R. Wedemeyer, B. Wiegers, F.W. Wieland, J. Wisskirchen Proceedings of the COSY Workshop on Baryon Excitations, Julich, Germany, 2-3 May 2000, Published in Juelich 2000, Baryon excitations, pp. 133-146.
65 Kaon photoproduction in a multipole approachT. Mart, A. SulaksonoPhysical Review C74:055203,2006 DOI:10.1103/PhysRevC.74.055203
The recently published experimental data on K+Lambda photoproduction by the SAPHIR, CLAS, and LEPS Collaborations are analyzed by means of a multipole approach. For this purpose the background amplitudes are constructed from appropriate Feynman diagrams in a gauge-invariant and crossing-symmetric fashion. The results of our calculation emphasize the lack of mutual consistency between the SAPHIR and CLAS data previously found by several independent research groups, whereas the LEPS data are found to be more consistent with those of CLAS. The use of SAPHIR and CLAS data, individually or simultaneously, leads to quite different resonance parameters that, therefore, could lead to different conclusions on "missing resonances." Fitting to the SAPHIR and LEPS data simultaneously indicates that the S11(1650), P13(1720), D13(1700), D13(2080), F15(1680), and F15(2000) resonances are required, whereas fitting to the combination of CLAS and LEPS data leads alternatively to the P13(1900), D13(2080), D15(1675), F15(1680),
66 Low densities instability of relativistic mean field models.A. Sulaksono, T. MartPhysical Review C74:045806,2006 DOI:10.1103/PhysRevC.74.045806
The effects of symmetry energy softening of relativistic mean field (RMF) models on the properties of matter with neutrino trapping are investigated. It is found that the effects are less significant than those in the case without neutrino trapping. The weak dependence of the equation of state on the symmetry energy is shown as the main reason for this finding. Using different RMF models the dynamical instabilities of uniform matters, with and without neutrino trapping, have been also studied. The interplay between the dominant contribution of the variation of matter composition and the role of effective masses of mesons and nucleons leads to higher critical densities for matter with neutrino trapping. Furthermore, the predicted critical density is insensitive to both the number of trapped neutrinos as well as the RMF model used in the investigation. It is also found that additional nonlinear terms in the Horowitz-Piekarewicz and Furnstahl-Serot-Tang models prevent another kind of instability, which occurs at
67 Effects of the neutrino electromagnetic form factors on the neutrino and antineutrino mean free paths in dense matter.P.T.P. Hutauruk, A. Sulaksono, T. Mart Nuclear Physics A782:400-405,2007DOI:10.1016/j.nuclphysa.2006.10.034
We have studied the effects of the nucleon weak magnetism and neutrino electromagnetic properties on the mean free paths difference between neutrino and antineutrino for all types of neutrinos. In the calculation, we consider matters with and without neutrino trapping as the targets. We have found that the difference depends on the neutrino energy, the matter used and the effect of different constituents in matter which manifests itself in different ways for each type of neutrino. Compared to the nucleon weak magnetism, the neutrino electromagnetic properties are found to have negligible effect on the mean free path difference.
68 K0 photoproduction on the deuteron and the extraction of the elementary amplitudeA. Salam, K. Miyagawa, T. Mart, C. Bennhold W. Glockle Physical Review C74:044004,2006DOI: 10.1103/PhysRevC.74.044004
The photoproduction of K0 on the deuteron has been investigated with the inclusion of the YN and KN final-state interaction (FSI), as well as the pion-mediated process gammad-->piNN-->KYN. The YN rescattering effects for the inclusive cross section are found to be large in the threshold regions. Polarization observables show sizable FSI effects at larger kaon and hyperon angles. It is shown that the extraction of the elementary gammaN-->KY amplitude is possible in the quasifree scattering region where FSI effects are negligible. Furthermore, the cross sections in this region are large, indicating that measurements in this kinematic region are favored.
69 Separation of the longitudinal and transverse cross-sections in the p(e, e-prime K+) Lambda and p(e, e-prime K+) Sigma0 reactionsR.M. Mohring,D. Abbott, A. Ahmidouch, T.A. Amatuni, P. Ambrozewicz, T. Angelescu, C.S. Armstrong, J. Arrington, K. Assamagan, S. Avery, K. Bailey, K. Beard, S. Beedoe, E.J. Beise, H. Breuer, R. Carlini, J. Cha, C.C. Chang, N. Chant, E. Cisbani, G. Collins, W. Cummings, S. Danagoulian, R. De Leo, F. Duncan, J. Dunne, D. Dutta, T. Eden, R. Ent, L. Eyraud, L. Ewell, M. Finn, T. Fortune, V. Frolov, S. Frullani, C. Furget, F. Garibaldi, D. Gaskell, D.F. Geesaman, P. Gueye, Kenneth Kurt Gustafsson, J.O. Hansen, M. Harvey, W. Hinton, E. Hungerford, M. Iodice, C. Jackson, C. Keppel, W. Kim, K. Kino, D. Koltenuk, S. Kox, L. Kramer, T. Leone, A. Lung, D. Mack, R. Madey, M. Maeda, S. Majewski, P. Markowitz, T. Mart, C.J. Martoff, D. Meekins, A. Mihul, J. Mitchell, H. Mkrtchyan, S. Mtingwa, I. Niculescu, R. Perrino, David H. Potterveld, J.W. Price, B.A. Raue, J.S. Real, J. Reinhold, P. Roos,
ABSTRACT: We report measurements of cross sections for the reaction 1H(e,e&#8242;K+)Y, for both the &#923; and &#931;0 hyperon states, at an invariant mass of W=1.84 GeV and four-momentum transfers 0.5
70 Kaon photoproduction and electroproduction on the deuteron with recoil polarization K. Miyagawa, T. Mart, C. Bennhold, Walter Gloeckle PiN Newsletters 16:318-320,2002
71 Photoproduction and electroproduction of kaons in a gauge invariant framework H. Haberzettl, C. Bennhold, T. Mart PiN Newsletters 15:230-233,1999
72 Hyperon polarization in kaon photoproduction from the deuteron H. Yamamura, K. Miyagawa, T. Mart, C. Bennhold, H. Haberzettl, Walter Gloeckle Proceedings of the 2nd KEK - Tanashi International Symposium on Hadron and Nuclear Physics with Electromagnetic Probes, Tanashi, Tokyo, Japan, 25-27 Oct 1999, pp. 119-123 Aailable from arXiv
ABSTRACT: We analyze the reaction gamma + d --> K^+ + Lambda (Sigma) + N using the Nijmegen soft core hyperon-nucleon interactions NSC97f and NSC89 and a recently updated production operator for the gamma + N --> K^+ + Lambda(Sigma) processes. Significant effects of the YN final state interaction are found near both the K^+ Lambda N and K^+ Sigma N thresholds.
73 Phenomenological aspects of kaon photoproduction on the nucleon T. Mart, S. Sumowidagdo, C. Bennhold, H. Haberzettl Proceedings of the 2nd KEK - Tanashi International Symposium on Hadron and Nuclear Physics with Electromagnetic Probes, Tanashi, Tokyo, Japan, 25-27 Oct 1999, pp. 113-118 Available from arXiv
ABSTRACT: Using an isobar model which can reproduce the existing experimental data of kaon photoproduction on the nucleon we investigate some related phenomenological aspects, i.e. the hadronic form factors, contributions of kaon-hyperon final states to the anomalous magnetic moment of the nucleon, and missing nucleon resonances. By reggeizing the appropriate propagators we extend the model to the higher photon energy regime.
74 Coupled Lambda N - Sigma N and Lambda N N - Sigma N N systems and hyperon nucleon interactions K. Miyagawa, H. Kamada, Walter Gloeckle, H. Yamamura, T. Mart, C. Bennhold Few Body Systems Supplement 12:324-329,2000 Available from arXiv
ABSTRACT: This paper summarizes our studies of the hypertriton and describes our findings on the hyperon-nucleon interaction, especially on the role of the $\Lambda N-\Sigma N$ coupling and the strengths of the $S$-wave $YN$ interactions. We briefly comment on our ongoing analyses with electromagnetic probes.
75 Measurement of gamma p --&gt; K0 Sigma+ at photon energies up to 1.55-GeVS. Goers, J. Barth, C. Bennhold, M. Bockhorst, W. Braun, A. Budzanowski, R. Burgwinkel, J. Ernst, K.H. Glander, J. Hannappel, N. Jopen, Henry G. Juengst, H. Kalinowsky, U. Kirch, F.J. Klein, F. Klein, E. Klempt, A. Kozela, R. Lawall, L. Lindemann, J. Link, T. Mart, D. Menze, W. Neuerburg, M. Paganetti, E. Paul, R. Plotzke, J. Scholmann, I. Schulday, M. Schumacher, W.J. Schwille, F. Smend, J. Smyrski, H.N. Tran, M.Q. Tran, H. van Pee, R. Wedemeyer, B. Wiegers, F.W. Wieland, J. WisskirchenPhysics Letters B464:331-338,1999&nbsp;&nbsp;DOI:10.1016/S0370-2693(99)01031-X&nbsp;&nbsp;
ABSTRACT: The reaction &#947;p&#8594;K0&#931;+ has been measured with the SAPHIR detector at the electron stretcher ring ELSA. The total cross section rises up to a peak value of 1.1&#956;b at a photon energy of 1.4 GeV. The differential cross sections d&#963;/d&#937; are consistent with being flat throughout the measured energy range. The first measurement of the &#931;+ polarization in photon induced reactions was obtained.
76 Nucleon resonances in eta and K photoproduction C. Bennhold, A. Waluyo, H. Haberzettl, T. Mart, G. Penner, T. Feuster, U. Mosel, L. Tiator Proceedings of the 2nd Workshop on Electronuclear Physics with Internal Targets and the BLAST Detector, Cambridge, Massachusetts, 28-30 May 1998, pp. 225-239
77 A New resonance in K+ Lambda electroproduction: The D(13)(1895) and its electromagnetic form-factors C. Bennhold, H. Haberzettl, T. Mart Proceedings of the 2nd ICTP International Conference on Perspectives in Hadronic Physics, Trieste, Italy, 10-14 May 1999, pp. 328-337 Available from arXiv
ABSTRACT: New SAPHIR p(gamma,K+)Lambda total cross section data show a resonance structure at a total c.m. energy around 1900 MeV. We investigate this feature with an isobar model and find that the structure can be well explained by including a new D_{13} resonance at 1895 MeV. Such a state has been predicted by a relativistic quark model at 1960 MeV with significant gamma-N and K-Lambda branching ratios. We demonstrate how the measurement of single and double polarization observables can be used to obtain additional information on this resonance. Using recent (e,e'K+) JLab data from Hall C we extract the electromagnetic form factors of this state.
78 Quasifree kaon photoproduction on nuclei F.X. Lee, T. Mart, C. Bennhold, L.E. Wright Nuclear Physics A695:237-272,2001 DOI:10.1016/S0375-9474(01)01098-3
ABSTRACT: Investigations of the quasifree reaction A$(\gamma, K Y)$B are presented in the distorted wave impulse approximation (DWIA). For this purpose, we present a revised tree-level model of elementary kaon photoproduction that incorporates hadronic form factors consistent with gauge invariance, uses SU(3) values for the Born couplings and uses resonances consistent with multi-channel analyses. The potential of exclusive quasifree kaon photoproduction on nuclei to reveal details of the hyperon-nucleus interaction is examined. Detailed predictions for the coincidence cross section, the photon asymmetry, and the hyperon polarization and their sensitivities to the ingredients of the model are obtained for all six production channels. Under selected kinematics these observables are found to be sensitive to the hyperon-nucleus final state interaction. Some polarization observables are found to be insensitive to distortion effects, making them ideal tools to search for possible medium modifications of the elemen
79 Inclusive K+ and exclusive K+ Y photoproduction on the deuteron: Lambda and Sigma threshold phenomenaH. Yamamura, K. Miyagawa , T. Mart, C. Bennhold, Walter Gloeckle Physical Review C61:014001,2000DOI: 10.1103/PhysRevC.61.014001
ABSTRACT: Inclusive $K^+$ and exclusive $K^+Y$ photoproduction on the deuteron are investigated theoretically. Modern hyperon-nucleon forces and a recently updated kaon photoproduction operator for the $\gamma +N\to K^++Y$ process are used. Sizable effects of the hyperon-nucleon final state interaction are found near the $K^+\Lambda N$ and $K^+\Sigma N$ thresholds in the inclusive reaction. Angular distributions for the exclusive process show clear $YN$ final state interaction effects in certain kinematic regions. Precise data especially for the inclusive process around the $K^+\Sigma N$ threshold would help to clarify the strength and property of the $\Lambda N-\Sigma N$ interaction.
80 Role of P13(1720) in K Sigma photoproductionT. MartPhysical Review C62:038201,2000&nbsp;DOI:10.1103/PhysRevC.62.038201 &nbsp;
ABSTRACT: Using an isobar model and the new saphir data we show that a better explanation of K0&#931;+ photoproduction can be achieved by including the P13(1720) resonance. We find that the inclusion of this state does not influence the K+&#931;0 channel appreciably, in contrast to the other three K&#931; channels, where the prominent effect is found in the K0&#931;+ channel. The extracted fractional decay width is consistent with the prediction of the quark model, whose magnitude is almost one order smaller than the value given by the Particle Data Group.
81 T. Mart, S. Sumowidagdo, D. Kusno, C. Bennhold, H. Haberzettl, Kaon photoproduction on the nucleon: Overview of some applications
Nuclear Physics A684:502-504,2001.
82 Nucleon resonances in meson nucleon scattering with strangeness production A. Waluyo, C. Bennhold, H. Haberzettl, G. Penner, U. Mosel, T. Mart Proceedings of the 18th Indonesian National Physics Symposium Available from arXiv
ABSTRACT: An effective Lagrangian model in a coupled channels framework is applied to extract nucleon resonance parameters. In the K-matrix approximation, we simultaneously analyze all the available data for the transitions from pi N to five possible meson-baryon final states, pi N, pipi N, eta N, K Lambda, and KSigma, in the energy range from pi N threshold up to W = 2 GeV. In this work, we focus our efforts on the K Sigma channel. In particular, we include a set of Delta resonances around 1900 MeV: the S31(1900), P31(1910), and P33(1920) states. In most cases the parameters of nucleon resonances determined by the fits are consistent with the commonly accepted values in the literature. We find that in the low-energy region, the S11(1650), P11(1710), and P13(1720) states are important for the p(pi-,K0)Sigma0 and p(pi-,K+)Sigma- processes while the P33(1600) and D33(1700) states are significant for the pure I=3/2 reaction p(pi+,K+)Sigma+. In the high energy region, we find a D13 state at 1945 MeV which is impo
83 An isobar model for the photoproduction and electroproduction of kaons on the nucleon T. Mart, C. Bennhold, H. Haberzettl PiN Newsletters 16:86-91,2002
84 Electromagnetic K+ production on the deuteron and hyperon nucleon interactions K. Miyagawa, T. Mart, C. Bennhold, Walter Gloeckle American Imstitute of Physics Conference Proceedings 603:459-462,2001 DOI:10.1063/1.1436660
ABSTRACT: Electro- and photo production processes of K+ on the deuteron are investigated theoretically and various observables including beam and recoil polarizations are predicted. Modern hyperon-nucleon forces as well as an updated production operator on the nucleon are used. Sizable effects of the hyperon-nucleon final state interaction are seen around the Lambda and Sigma thresholds. (c)2001 American Institute of Physics.
85 New results on eta and eta photoproduction with SAPHIR at ELSA J. Barth, C. Bennhold, W. Braun, J. Ernst, K. H. Glander, S. Goers, J. Hannappel, N. Joepen, H. Kalinowsky, F. Klein, E. Klempt, A. Kozela, R. Lawall, J. Link, T. Mart, D. Menze, W. Neuerburg, M. Ostrick, E. Paul, H. van Pee, I. Schulday, W. -J. Schwille, J. Smyrski, U. Thoma, R. Wedemeyer, B. Wiegers, F. W. Wieland and J. Wi&szlig;kirchen Nuclear Physics A691:374-380,2001 DOI:10.1016/S0375-9474(01)01059-4
86 Gauge - invariant description of photoproduction and electroproduction of mesons with extended nucleons applied to kaon production H. Haberzettl, C. Bennhold, T. Mart Nuclear Physics A684:475-477,2001 DOI:10.1016/S0375-9474(01)00510-3
87 Final state interaction in kaon photoproduction from the deuteron H. Yamamura, K. Miyagawa, T. Mart, C. Bennhold, Walter Gloeckle Few Body Systems Supplement 12:387-390,2000
88 Photoproduction and electroproduction of mesons in a gauge-invariant framework H. Haberzettl, C. Bennhold, T. Mart Acta Physica Polonica B31:2387-2394,2000 Acta Physica Polonica Server
ABSTRACT: A comprehensive formalism is presented to describe the photo- or electroproduction of mesons off the nucleon. Taking the hadrons as extended objects described by form factors, we discuss the issues of gauge invariance and of off-shell form factors (both hadronic and electromagnetic). Specifically, we show how the gauge invariance of the production current is preserved by introducing auxiliary currents which take the place of the exchange currents usually neglected entirely in practical applications. The relation of the present formulation to tree-level-type prescriptions is discussed. Applications to kaon photoproduction are shown. PACS numbers: 25.20.Lj, 24.10.Jv, 13.75.Gx, 24.10.Eq
89 Electromagnetic K+ production on the deuteron with hyperon recoil polarization. K. Miyagawa, H. Yamamura, T. Mart, C. Bennhold, H. Haberzettl, Walter Gloeckle Nuclear Physics A691:64-67,2001 DOI:10.1016/S0375-9474(01)01008-9
ABSTRACT: Photo- and electroproduction processes of K+ on the deuteron are investigated theoretically. Modern hyperon-nucleon forces as well as an updated kaon production operator on the nucleon are used. Sizable effects of the hyperon-nucleon final state interaction are seen in various observables. Especially the photoproduction double polarization observable C_z is shown to provide a handle to distinguish different hyperon-nucleon force models.
90 Hypernuclear physics with photons C. Bennhold, T. Mart, F.X. Lee, H. Haberzettl, H. Yamamura, K. Miyagawa, W. Gloeckle, S.S. Kamalov, L. Tiator, L.E. Wright Proceedings of the Workshop on Hypernuclear Physics with Electromagnetic Probes (HYJLAB99), Hampton, Virginia, 2-4 Dec 1999 Available from arXiv
ABSTRACT: We review the opportunities and challenges in the field of hypernuclear physics with electromagnetic probes. An overview is presented regarding our current understanding of the elementary production process on the nucleon. This amplitude is then used in the nuclear environment to study the hyperon-nucleon (YN) interaction. We discuss two scenarios: hypernuclear excitation that allows the investigation of hypernuclear structure and the bound Lambda in the nucleus, and quasifree kaon production on the deuteron and on nuclei, which permits a more direct access to the YN force. Specific examples are given for few-body systems and shell-model nuclei.
91 Missing nucleon resonances in kaon production with pions and photons C. Bennhold, A. Waluyo, H. Haberzettl, T. Mart, G. Penner, U. Mosel In Newport News 2000, Excited nucleons and hadronic structure, pp. 280-287 Available from arXiv
ABSTRACT: Resonances with strong couplings to strangeness channels are investigated in a coupled-channels framework of kaon production with pions and photons. We find evidence for an additional D13 resonance around 1900 MeV that has a significant decay width into the K Lambda final state. Such a state has been predicted in a relativistic quark model at 1960 MeV with significant gamma N and K Lambda branching ratios.
92 Evidence for a missing nucleon resonance in kaon photoproductionT. Mart , C. BennholdPhysical Review C61:012201,2000&nbsp;DOI:10.1103/PhysRevC.61.012201&nbsp;
ABSTRACT: New SAPHIR p(gamma,K+)Lambda total cross section data show a resonance structure at a total c.m. energy around 1900 MeV. We investigate this feature with an isobar model and find that the structure can be well explained by including a new D_{13} resonance at 1895 MeV. Such a state has been predicted by a relativistic quark model at 1960 MeV with significant gamma-N and K-Lambda branching ratios. We demonstrate how the measurement of the photon asymmetry can be used to further study this resonance. In addition, verification of the predicted large decay widths into the eta-N and eta'-N channels would allow distinguishing between other nearby D_{13} states.