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Abstrak :
[ABSTRAK
Kuantisasi Lagrangian model point-coupling bergantung densitas menghasilkan Lagrangian Hartree-Fock yang terdiri atas suku direct dan exchange. Identitas Fierz diaplikasikan pada suku exchange agar bisa disusun bersama dengan suku direct membentuk Lagrangian efektif. Dengan menggunakan persamaan Euler-Lagrange akan didapat persamaan gerak dan massa efektif sistem. Dari Hamiltonian sistem diperoleh energi ikat sistem per nukleon, massa efektif, tekanan dan kompresibilitas. Dari hasil yang diperoleh, kontribusi suku exchange kecil pada massa efektif nukleon materi nuklir simetrik. Namun pada keadaan lain, kontribusi yang signikan terlihat pada energi ikat per nukleon di materi nuklir simetrik dan materi netron, massa efektif materi netron, dan energi ikat per nukleon pada densitas rendah dari materi netron.

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ABSTRACT
Point-coupling model Lagrangian is quantized to obtain the Hartree-Fock Lagrangian which contained direct and exchange terms. Fierz identity applied to the exchange term to be rearranged together with the direct term to obtain the eective Lagrangian. By using the Euler-Lagrange equation, we will obtain the equation of motion and the eective mass of the system. From the Hamiltonian will obtain the binding energy per nucleon, eective mass, pressure and compressibility. The results show that the exchange term contribution is small on nucleon eective mass of symmetric nuclear matter. But in the other conditions, the signicant contribution are observed on binding energy per nucleon of asymmetric nuclear matter, neutron eective mass, and binding energy per nucleon in asymmetric nuclear matter in low density;Point-coupling model Lagrangian is quantized to obtain the Hartree-Fock Lagrangian which contained direct and exchange terms. Fierz identity applied to the exchange term to be rearranged together with the direct term to obtain the eective Lagrangian. By using the Euler-Lagrange equation, we will obtain the equation of motion and the eective mass of the system. From the Hamiltonian will obtain the binding energy per nucleon, eective mass, pressure and compressibility. The results show that the exchange term contribution is small on nucleon eective mass of symmetric nuclear matter. But in the other conditions, the signicant contribution are observed on binding energy per nucleon of asymmetric nuclear matter, neutron eective mass, and binding energy per nucleon in asymmetric nuclear matter in low density;Point-coupling model Lagrangian is quantized to obtain the Hartree-Fock Lagrangian which contained direct and exchange terms. Fierz identity applied to the exchange term to be rearranged together with the direct term to obtain the eective Lagrangian. By using the Euler-Lagrange equation, we will obtain the equation of motion and the eective mass of the system. From the Hamiltonian will obtain the binding energy per nucleon, eective mass, pressure and compressibility. The results show that the exchange term contribution is small on nucleon eective mass of symmetric nuclear matter. But in the other conditions, the signicant contribution are observed on binding energy per nucleon of asymmetric nuclear matter, neutron eective mass, and binding energy per nucleon in asymmetric nuclear matter in low density;Point-coupling model Lagrangian is quantized to obtain the Hartree-Fock Lagrangian which contained direct and exchange terms. Fierz identity applied to the exchange term to be rearranged together with the direct term to obtain the eective Lagrangian. By using the Euler-Lagrange equation, we will obtain the equation of motion and the eective mass of the system. From the Hamiltonian will obtain the binding energy per nucleon, eective mass, pressure and compressibility. The results show that the exchange term contribution is small on nucleon eective mass of symmetric nuclear matter. But in the other conditions, the signicant contribution are observed on binding energy per nucleon of asymmetric nuclear matter, neutron eective mass, and binding energy per nucleon in asymmetric nuclear matter in low density, Point-coupling model Lagrangian is quantized to obtain the Hartree-Fock Lagrangian which contained direct and exchange terms. Fierz identity applied to the exchange term to be rearranged together with the direct term to obtain the eective Lagrangian. By using the Euler-Lagrange equation, we will obtain the equation of motion and the eective mass of the system. From the Hamiltonian will obtain the binding energy per nucleon, eective mass, pressure and compressibility. The results show that the exchange term contribution is small on nucleon eective mass of symmetric nuclear matter. But in the other conditions, the signicant contribution are observed on binding energy per nucleon of asymmetric nuclear matter, neutron eective mass, and binding energy per nucleon in asymmetric nuclear matter in low density]

Abstrak :
Fotoproduksi meson η′ pada nukleon dipelajari dengan menggunakan model interaksi Lagrangian efektif. Model interaksi Lagrangian efektif digunakan untuk menghitung amplitudo transisi dengan memperhitungkan kontribusi dari kanal-s non-resonan, kanal-u non-resonan, kanal-t, serta resonan nukleon spin 1/2 N*(1895) dan N*(1895), dan spin 3/2. Faktor bentuk digunakan hanya pada kanal-t agar amplitudo transisi yang didapatkan tetap Gauge Invarian. Amplitudo transisi invarian yang telah didapatkan kemudian didekomposisi menjadi matriks-matriks dalam bentuk yang mempermudah dalam melakukan perhitungan numerik. Nilai yang dicari adalah penampang lintang differensial dengan dengan menggunakan energi sistem dari 1.925 MeV sampai 2.795 MeV dalam beberapa variasi sudut θ. Fitting grafik hubungan penampang lintang differensial dengan energi sistem dalam beberapa variasi sudut menunjukkan terjadinya divergensi penampang lintang sebagian seiring dengan meningkatnya energi sistem. ......η' meson photoproduction off nucleon is studied by using the effective Lagrangian approach. Effective Lagrangian approach were used to calculate the transition amplitude of the reaction by including the contribution of the non-resonant s- and u-channel, the vector meson exchange terms, and also the nucleon resonances of spin-1/2 N*(1895) and N*(2100), and spin-3/2. Form factor was used only on the t-channel so that the transition amplitude’s gauge invariance was conserved. The invariant transition amplitude then was decomposed into matrices which can help to simplify the numerical calculation. The observables that were investigated were the differential cross section with the energy of the system from 1.925 MeV up to 2.975 MeV in several angles θ variation. The fitting graph of the relation between differential cross section and energy of the system in several angles variation displays that the differential cross section was divergent as the energy of the system rises.

Abstrak :
Kami mempelajari kontribusi dari masing-masing kanal pertukaran dari fotoproduksi K*(892) yang didasarkan oleh model efektif Lagrangian. Selain itu, kami juga mempertimbangkan penambahan kontribusi dari partikel Σ*(1780) sebagai partikel resonans hiperon tambahan disamping dengan partikel Σ*(1385) yang sudah mapan, untuk menunjukkan efek dari kontribusi tambahan pada daerah backward scattering yang menyebabkan deviasi diantara model yang diajukan dengan data eksperimen prilem yang dihasilkan oleh kolaborasi CLAS, sebagai petunjuk bahwa ada kontribusi nontrivial pada kanal pertukaran u. Penelitian ini dapat bermanfaat kedepannya untuk membangun pemahaman yang lebih dalam dari mekanisme fotoproduksi K*. ......We study the contributions of each exchange channels of the K*(892) photoproduction based on the effective Lagrangian model. In addition, we consider the contribution of the Σ*(1780) as an additional hyperon resonance alongside the Σ*(1385), to demonstrate the effect of additional contributions in the backward scattering region that caused a discrepancy between the original model with the preliminary experiment data produced by the CLAS collaborations, hinting a possible non-trivial contributions to the u-channel. These study could be advantageous to establish a deeper background on the mechanism of the K* photoproduction.

Abstrak :

Fotoproduksi partikel merupakan interaksi antara suatu partikel dengan foton yang menghasilkan partikel-partikel tertentu pada keadaan akhirnya. Salah satu reaksi fotoproduksi yang diteliti selama bertahun-tahun adalah fotoproduksi partikel kaon. Berdasarkan hukum kekekalan yang berlaku pada tiap interaksinya, fotoproduksi kaon memungkinkan untuk menghasilkan dua partikel kaon dalam keadaan akhirnya. Pada skripsi ini, telah dibahas dan diturunkan amplitudo dan penampang lintang fotoproduksi kaon ganda berdasarkan diagram Feynman dan Lagrangian efektif interaksi (model isobar). Penurunan tersebut mempertimbangkan kontribusi dari partikel resonans hiperon sampai dengan spin $1/2$ dan partikel resonans kaon sampai dengan spin $1$. Reaksi fotoproduksi kaon ganda yang dibahas, antara lain $\gamma\ p\ \to K^+\ K^0\ \Xi^0$, $\gamma\ p\ \to K^+\ K^+\ \Xi^-$, $\gamma\ n\ \to K^0\ K^0\ \Xi^0$, $\gamma\ n\ \to K^0\ K^+\ \Xi^-$, dan $\gamma N \to K K N$. ......Particle photoproduction is an interaction between certain particle and photon resulting in other particles produced in the final state. One of the well studied photoproduction reaction is the photoproduction of kaon. It is shown that by using conservation laws for particle interaction, a photoproduction reaction resulting in two kaon in the final state is permitted. Here we show the derivation of the production amplitude and cross section based on Feynman diagrams or effective Lagrangian (isobar model) approach. Our calculation includes the contribution of hyperon resonance up to spin-$1/2$ and kaon resonance up to spin-$1$. The discussed double kaon photoproduction reactions are $\gamma\ p\ \to K^+\ K^0\ \Xi^0$, $\gamma\ p\ \to K^+\ K^+\ \Xi^-$, $\gamma\ n\ \to K^0\ K^0\ \Xi^0$, $\gamma\ n\ \to K^0\ K^+\ \Xi^-$, and $\gamma N \to K K N$.