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"[ABSTRAKSemakin baik dan banyaknya hasil eksperimen di bidang nuklir, menjadi faktor pendorongbagi fisikawan nuklir untuk melakukan penelitian lebih lanjut mengenai interaksidan struktur nuklir. Alhasil, banyak reaksi yang bertujuan untuk menjelaskan,membandingkan bahkan memperkirakan hal ini, salah satunya adalah fotoproduksikaon netral pada deuteron. Telah dipelajari sebuah model sederhana untuk reaksifotoproduksi kaon netral pada deuteron yaitu model isobar dengan menggunakanpendekatan impuls. Penelitian ini bertujuan untuk mempelajari penampang lintangeksklusif dan inklusif dari fotoproduksi kaon netral pada deuteron dengan beberapakeadaan kinematik, dan dibandingkan dengan eksperimen [6]. Hasil yang didapatkanmenunjukkan penampang lintang inklusif lebih besar daripada penampang lintangeksklusif karena pada penampang lintang inklusif hanya mendeteksi kaon saja, danuntuk penampang lintang eksklusif mendeteksi kaon dan hiperon secara simultan,makin banyak partikel yang dideteksi makin kecil penampang lintangnya. Penampanglintang eksklusif dengan momentum proton = 0 lebih besar dibandingkan denganmomentum proton tidak nol, hal ini dikarenakan peluang terjadinya reaksilebih besar ketika neutron dalam deuteron diam. Untuk penampang lintang eksklusifdengan variasi momentum proton, paling besar penampangnya berada pada arahsumbu Z, yaitu searah dengan masuknya proyektil foton riil saat terjadinya reaksi.Kaon paling banyak mengalami hamburan pada sudut kecil, sementara pada sudutyang besar penampang lintangnya kecil. Amplitudo transisi deuteron berperan pentingdalam reaksi eksklusif maupun inklusif yaitu dalam menentukan puncak-puncakkurva penampang lintang tersebut.

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ABSTRACTThe abundance experimental results in the nuclear eld, becomes a driving factor fornuclear physicists to conduct further research on interactions and nuclear structure.As a result, many reactions aims to explain, compare and even estimate it, one ofwhich is the neutral kaon photoproduction on deuteron. It has been studied a simplemodel for the reaction of the neutral kaon photoproduction on deuteron with isobarsmodel using impulse approximation. This research aims to learn the exclusiveand inclusive cross section of neutral kaon photoproduction on deuteron with somekinematic state, and compared with experiments [6]. The results obtained indicatethe inclusive cross section larger than the exclusive cross section because for theinclusive cross section only detect kaon, and exclusive cross section detect kaon andhyperon simultaneously, more particles are detected the smaller cross section will be.Exclusive cross section with proton momentum = 0 is larger than when proton momentumis not zero, because of the possibilty for greater reaction is when a neutronin the deuteron is not moving. For the exclusive cross section with variation protonmomentum, the largest cross section is in the axis-Z, that have the same directionwith the entry of projectile photon real. Kaon experiences the most scattering atsmall angles, while at large angles have a small cross section. Transition amplitudeon deuteron plays an important role in the reaction that exclusive or inclusive indetermining the peaks of the cross section of the curve, The abundance experimental results in the nuclear eld, becomes a driving factor fornuclear physicists to conduct further research on interactions and nuclear structure.As a result, many reactions aims to explain, compare and even estimate it, one ofwhich is the neutral kaon photoproduction on deuteron. It has been studied a simplemodel for the reaction of the neutral kaon photoproduction on deuteron with isobarsmodel using impulse approximation. This research aims to learn the exclusiveand inclusive cross section of neutral kaon photoproduction on deuteron with somekinematic state, and compared with experiments [6]. The results obtained indicatethe inclusive cross section larger than the exclusive cross section because for theinclusive cross section only detect kaon, and exclusive cross section detect kaon andhyperon simultaneously, more particles are detected the smaller cross section will be.Exclusive cross section with proton momentum = 0 is larger than when proton momentumis not zero, because of the possibilty for greater reaction is when a neutronin the deuteron is not moving. For the exclusive cross section with variation protonmomentum, the largest cross section is in the axis-Z, that have the same directionwith the entry of projectile photon real. Kaon experiences the most scattering atsmall angles, while at large angles have a small cross section. Transition amplitudeon deuteron plays an important role in the reaction that exclusive or inclusive indetermining the peaks of the cross section of the curve]"

"Telah dilakukan perhitungan pergeseran fase hamburan pion-nukleon dengan menerapkan interaksi separabel rank-1 untuk gelombang parsial S, P, dan D. Bentuk separabel membuat persamaan Lippmann-Sehwinger dapat diselesaikan seeara analitik. Parameter interaksi ditentukan melalui fitting dengan data pergeseran fase dari analisa SAID. Keeocokan yang baik dieapai untuk momentum hingga 400 MeV/e, sementara tidak begitu baik untuk hingga 1500 MeV/c.

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Phaseshifts of pion-nucleon scattering have been calculated by using separable interaction of rank-l for the partial Waves S, P, and D. With the separable form, the Lipprnann-Schvvinger equation can be solved analytically. lnteraction parameters are determined through fitting with the phaseshift data from SAID analysis. Good fits can be achieved for the 1no1nenta up to 400 MeV/c, While not so good for up to 1500 MeV/c."

"[ABSTRAKTelah dipelajari dan dikembangkan sebuah model sederhana untuk reaksi fotoproduksikaon pada neutron dari deuteron yaitu model isobar dengan menggunakanpendekatan impuls. Nilai yang dicari adalah nilai penampang lintang diferensialdengan variasi energi foton dimulai dari 1,15 GeV-3,55 GeV. Hasil penelitian inimenunjukkan reaksi + n ! K++􀀀 dapat diektraksi dari reaksi + d ! K++􀀀+ p. Selain itu dapat disimpulkan bahwa hasil penelitian antara data teori dengandata eksperimen berbeda jauh, data teori melampaui jauh diatas nilai data eksperimen.Salah satu faktor yang menyebabkan hasil data teori dengan eksperimenjauh berbeda disebabkan oleh elemen operator dimana nilai elemen operator yangdigunakan memiliki nilai maksimum 2 GeV sedangkan data ekperimen hingga mencapainilai 3 GeV. Hal inilah yang menyebabkan data teori dengan menggunakanmodel missing resonans harus dikalikan dengan faktor pengali agar t dengan hasileksperimen.

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ABSTRACTHas been studied and developed A simple model for reaction of positive kaon onneutron from deuteron in a isobaric model using impulse approximation. The calculationcovered dierential cross section. The value is analyzed with energy rangestart from 1.15-3.55 GeV. The result show that the cross section for + n! K++􀀀can be extracted from the reaction + d ! K+ + 􀀀 + p. The research can beconcluded that the result of theory is over predicted and the one of this factor isoperator elementary that the maximum value we used is 2 GeV, whereas the resultof experiment until 3 GeV. This is make me the theory data using missing resonancemust be times with a times factor to t with the experiment result, Has been studied and developed A simple model for reaction of positive kaon onneutron from deuteron in a isobaric model using impulse approximation. The calculationcovered dierential cross section. The value is analyzed with energy rangestart from 1.15-3.55 GeV. The result show that the cross section for + n! K++􀀀can be extracted from the reaction + d ! K+ + 􀀀 + p. The research can beconcluded that the result of theory is over predicted and the one of this factor isoperator elementary that the maximum value we used is 2 GeV, whereas the resultof experiment until 3 GeV. This is make me the theory data using missing resonancemust be times with a times factor to t with the experiment result]"

"During the first and second year of the research activities, the following progress has been achieved:1. Investigation of the Response Functions. All possible Response Functions in photo- and electroproduction of kaons on the nucleon have been investigated in the framework of an isobaric model. We found that some Response Functions are sensitive to the choice of the strange hadron form factors. Meanwhile, we have also improved the elementary model for kaon photoproduction by using a certain method to maintain gauge invariance of the amplitude. We have published the results in Ref. [1, 2, 3] (see attachments).2. Some Phenomenological Aspects in Kaon Photoproduction. The elementary operator can be used to study some interesting aspects in kaon photoproduction, i.e. the Gerasimov-Drell-Hearn sum-rule and the missing resonance in kaon photoproduction. We have published the results in Ref. [4, 5]3. Photoproduction of Kaon off a Deuteron. Using an established and consistent model for kaon photoproduction on the nucleon, we have calculated photoproduction of kaons on the deuteron in the frame-work of the nucleon spectator model. We have compared the result with the previous study by Xiaodong Li et. al. [6] in Ref. [7]4. Photoproduction of Kaon off a Deuteron with Final State Interactions. The previous work has been extended by including the effects from final state inter-actions (FSI). To achieve this, we used the formalism of three-body wave functions developed by the Okayama-Bochum group. The results have been published in Ref. [8].5. Electroproduction of Kaon off a Deuteron with Final State Interactions.As the final work of this project, we have finished the fortran code for calculating kaon electroproduction of a deuteron. This part became a collaborated work with the Okayama-Bochum group."

"Investigation of the Response Functions. All possible Response Functions in photo- and electroproduction of kaons on the nucleon have been investigated in the framework of an isobaric model. We found that some Response Functions are sensitive to the choice of the strange hadron form factors. Meanwhile, we have also improved the elementary model for kaon photoproduction by using a certain method to maintain gauge invariance of the amplitude. We have published the results in Ref. [I, 2, 3] (see attachments). Photoproduction of Kaon off a Deuteron. Using an established and consistent model for kaon photoproduction on the nucleon, we have calculated photoproduction of kaons on the deuteron in the frame-work of the nucleon spectator model. We have compared the result with the previous study by Xiaodong Li et. al. [4]."

"ABSTRAKPenyelidikan tentang faktor bentuk hadronik pada fotoproduksi kaon telah menghasilkanmodel standar terbaik. Model standar terbaik berisi kombinasi faktorbentuk hadronik untuk masing-masing vertex fotoproduksi kaon yang diselidikimenggunakan model isobar. Nilai c2=N minimum yang diperoleh dari modelstandar terbaik adalah 2.13. Masing-masing vertex fotoproduksi kaon memilikikesesuaian penggunaan faktor bentuk hadronik yang berbeda-beda, antara lainmenggunakan jenis dipole, eksponensial, generalized dipole (1), generalizeddipole (2), atau generalized dipole (3). Selain kombinasi faktor bentuk hadronik,model standar terbaik juga menghasilkan nilai parameter cut-off untuk setiap vertexnya.Upaya perbaikan terhadap model standar terbaik dilakukan dengan seleksidata eksperimen berdasarkan analisis konsistensi data dan seleksi berdasarkansimpangan R. Namun, hasil seleksi data kurang memuaskan karena tidak adapenurunan nilai c2=N yang signifikan. Parameter cut-off dan konstanta koplingjuga diselidiki pengaruhnya terhadap model dengan cara memvariasikan nilaikeduanya. Variasi parameter cut-off untuk vertex meson K(892) dengan kenaikandan penurunan 10% menyebabkan adanya pergeseran hasil fit dari model standarterbaik. Sementara itu, variasi konstanta kopling tidak menghasilkan perubahancukup besar pada model standar terbaik.

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ABSTRACTWe have produced the best standard model of kaon photoproduction off the protonusing hadronic form factors. The best standard model, which is investigated usingisobar model, contains combination of hadronic form factors for each vertex in kaonphotoproduction. The value of c2=N achieved in this work is 2.13. Each vertexsof kaon photoproduction perform different suitability using several hadronic formfactors, those are the dipole, exponential, generalized dipole (1), generalized dipole(2), or else generalized dipole (3). Furthermore, the best standard model producedthe specific value of cut-off parameter for each vertex. We also try to improve thebest standard model by selecting the experimental data using consistency analysismethod and deviation method. However, both methods perform no improvement. Inthe final work, we investigate the effect of cut-off parameter and coupling constanton the best standard model by varying their values. Cut-off parameter for K(892)meson show different result from the best standard model after varying its value inthe range of 10%. Meanwhile, variation on coupling constant perform not enoughdifferences to be noted."

"Penelitian ini ingin melihat seberapa jauh kontribusi resonansi hyperon dengan spin 5/2 pada energi tinggi dengan menggunakan model isobar untuk fotoproduksi kaon pada proton, γp → K+Λ. Resonansi hyperon yang dimasukkan adalah resonansi dengan spin 1/2 yang merupakan resonansi latar ditambah dengan resonansi berspin 5/2 yang tercatat pada Particle Data Group. Beberapa studi menyatakan bahwa resonansi hyperon ini berguna pada perhitungan sudut mundur pada fotoproduksi kaon. Perhitungan ini menggunakan nilai amplitudo hamburan yang diturunkan secara analitik dan dimasukkan ke dalam perhitungan numerik. Dalam mencari sejauh mana kontribusi hyperon dengan spin 5/2 ini, penelitian dilakukan dengan cara meminimalisasi nilai χ2/N serta melihat sejauh mana keselarasan model yang digunakan dengan data eksperimen, terutama pada penampang lintang dan observabel polarisasi.

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This research is aimed to investigate the contribution of spin-5/2 hyperon resonances by using an isobar model for kaon photoproduction on the proton γp → K+Λ. Hyperon resonances with spin-1/2 and -5/2 listed by the Particle Data Group are included in the model. It is found in the literature that, the hyperon resonance contributes mostly in the backward angles of kaon photoproduction. For this purpose the amplitude is calculated analitically and the result is used in the numerically calculation. Contribution of spin-5/2 hyperon resonances is investigated by minimizing the χ2/N values and improving the consistency of the model with the experimental data, especially the crosssection and polarization observables."

"Dalam fotoproduksi kaon, banyak data eksperimen yang telah didapatkan namun masih sedikit teori yang dapat menjelaskan hasil tersebut dengan baik. Dengan meneliti peran resonans hyperon dalam fotoproduksi kaon, diharapkan dapat memahami reaksi ini dengan lebih baik. Penelitian ini menggunakan metode Lagrangian efektif dengan interaksi yang lebih konsisten untuk mencari nilai amplitudo hamburan, kemudian parameter yang tidak diketahui dalam amplitudo hamburan dicocokkan dengan data eksperimen dengan meminimalisasikan nilai χ2/N. Data eksperimen yang digunakan ialah penampang lintang dan observabel polarisasi. Hasil yang didapatkan menunjukkan nilai yang lebih sesuai dengan data eksperimen, terutama pada daerah sudut mundur.

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Kaon photoproduction has been investigated and experimented but still few theories can explain it well. Investigating hyperon resonance in kaon photoproduction may provide a better explanation about this process. This study was conducted by using an effective Langrangian method with consistent interaction to calculate scattering amplitude, then the unknown parameters in scattering amplitude would be fitted with experimental data by minimizing χ2/N value. Experimental data which is used are cross-section and polarization observable. The results showed values more precise with the experimental data, especially at backward angle."

"Dalam beberapa puluh tahun terakhir, fotoproduksi kaon telah menjadi salah satu kanal yang dikenal berpotensi untuk menemukan missing resonances yang telah diprediksi oleh Quark Model, akan tetapi belum dikonfirmasi oleh eksperimen. Namun kanal reaksi ini memiliki kesulitan-kesulitan tersendiri, yaitu cross section rendah dan energi threshold yang sangat tinggi. Energi threshold untuk fotoproduksi kaon adalah 911 MeV, sangat tinggi jika dibandingkan dengan energi threshold untuk fotoproduksi pion, yaitu 150 MeV. Penentuan background yang tepat menjadi penting untuk menentukan kontribusi resonans. Saat ini kontribusi resonans dapat ditentukan dengan menggunakan sebuah metode pengambilan keputusan dalam statistik, yang disebut dengan Metode Bayesian. Metode ini tidak hanya mengevaluasi sebuah model pada seluruh parameternya, namun juga memasukkan distribusi prior dan data eksperimen ke dalam perhitungan. Analisis menggunakan metode ini menunjukkan bahwa sekumpulan resonans menggambarkan proses fotoproduksi kaon dengan lebih baik dari pada sekumpulan resonans lainnya.

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Kaon photoproduction has drawn considerable attention for decades as one of the promising processes to find the missing nucleon resonances, predicted by quark model but not listed yet by the Particle Data Group. Nevertheless, this channel has a unique difficulty, e.g., the small cross section and high threshold energy. the threshold energy for kaon photoproduction is 911 MeV, significantly high compared with that of the pion photoproduction, i.e. 150 MeV. Determining the background part of the process becomes a daunting task in order to approximate the resonance contribution. At present, the resonance contribution can be determined by using an established statistical decision making method, which is called the Bayesian Method. This method does not only evaluate the model over its entire parameter space, but also takes the prior information and experimental data into account. Analysis using this Bayesian Method showed that a set of resonances can describe kaon photoproduction better than others."