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Abstrak :
Telah dilakukan penentuan karakteristik sumber beta 90Sr/90Y dengan menggunakan simulasi Monte Carlo BEAMnrc yang berbasiskan metode Monte Carlo serta penghitungan BEAMDP dan FLURZnrc terutama fluks dan energi-fluks sebagai fungsi posisi, distribusi energi-fluks, distribusi energi spektral, serta distribusi energi rata-rata. Energi rata-rata radiasi elektron yang dihasilkan berkisar 0,75 MeV dan foton pada 0,15 MeV. Partikel radiasi elektron masih dominan dengan jumlah partikel lebih dari 54% jumlah total partikel radiasi (berdasarkan fluks vs posisi, dan distribusi energi spektral), dan energi-fluks maksimumnya sekitar 1,9x10-5 partikel.MeV (87%). Distribusi energi-fluks menunjukkan nilai maksimum di sekitar 7x10-6 partikel.MeV pada energi 0,96 MeV untuk elektron, dan 3,9x10-6 partikel.MeV pada energi 0,10 MeV untuk foton. Juga diperoleh kepastian ketidakhadiran positron. Besar dosis keluaran (menggunakan DOSXYZ) sumber radiasi di sekitar permukaan sumber adalah 3,6x10-13 Gy dan menurun secara eksponensial ketika menjauhi sumber. ......A Monte Carlo study has been done on 90Sr/90Y beta source using BEAMnrc protocol including BEAMDP and FLURZnrc calculation to determine flux and energy-flux as a function of positions, energy-flux and energy spectral distribution, and also average energy. Average electron energy was found to be 0.75 MeV and average photon energy at 0.15 MeV. The domination of electron were shown by more than 54% in number (based on flux vs. position, and energy spectral distribution), and the maximum of energy-flux was about 1.9x10-5 particle.MeV (87%). Energy-flux distribution showed that the maximum value was about 7x10-6 particle.MeV at 0.96 MeV for electron, and 3.9x10-6 particle.MeV at 0.10 MeV for photon. There is a definite absence of positron. Dose around the surface were found using DOSXYZ source to be 3.6x10-13 Gy and it is exponentially decayed at distance.

Abstrak :
Kita membandingkan dua bentuk propagator yang berbeda yaitu bentuk propagator yang disederhanakan dan bentuk propagator yang lengkap dari resonans nukleon spin-3/2 dan spin-5/2 dengan menggunakan model isobar dan pendekatan Lagranggian efektif pada fotoproduksi eta-meson pada proton γ + N -> η + N. Kita menghitung amplitude transisi dengan memasukkan suku Born, suku vektor-meson, dan resonans nukleon ( N1(1520)D13, N2(1535)S11, N3(1650)S11, N4(1675)D15, N5(1680)F15, N6(1700)D13, N7(1710)P11, dan N8(1720)P13 ). Parameter konstanta kopling diperoleh berdasarkan hasil perhitungan dari formula yang telah ditetapkan dengan data input berdasarkan data partikel. ......We compare two different propagator forms that are simple and complete propagators of spin-3/2 and spin-5/2 nucleon resonances by using isobar models and effective Lagrangian approach for eta-meson photoproduction on the proton γ + N -> η + N. We calculate the transition amplitudes by including Born term, vector-meson term, and nucleon resonances ( N1(1520)D13, N2(1535)S11, N3(1650)S11, N4(1675)D15, N5(1680)F15, N6(1700)D13, N7(1710)P11, and N8(1720)P13 ). The coupling constant parameters are obtained based on the calculation results based on the particle data group.

Abstrak :
Pion pertama kali diproduksi pada suatu percobaan dengan menggunakan sebuah Cyclotron yang terdapat di Berkeley,Amerika serikat . Massa dari Pionm‚ = 273me, dengan me = 0.511MeV. Pada umumnya dalam Interaksi Pion-Nukleon dikerjakan menggunakan model Kuark yang konsekuensinya menggunakan pendekatan interaksi kuat dengan model Kuark dimana masing-masing Gluon yang terdapat pada Kuark berinteraksi satu sama lainnya. Namun bagaimana kah jika kita menurunkan level energy terjadinya interaksi menjadi sangat rendah? Apakah kita bisa menggunakan pendekatan model interaksi lemah yang terjadi pada Foton dalam interaksi elektromagnetik? Apakah dalam pendekatan level energy rendah kita bisa membuat Gluon menjadi seperti Foton? Yang mana kita telah mengetahui bahwa terdapat perbedaan yangmencolok antara Foton dan Gluon. Gluon bisa berinteraksi diantara sesamanya dengan interaksi muatan kuantum warna sedangkan Foton tidak dapat berinteraksi diantara sesamanya. Tujuan dari penelitian ini adalah untuk membuat suatu model dari fotoproduksi Pion pada Nukleon dalam Suku-suku Born. ...... Pion was produced in an experiment using a Cyclotron located in Berkeley, United States at the first time. The Mass of Pion , m‚= 273mewithme = 0.511MeV. Generally Interactions of Pion-Nucleon have been doing in quark model which the consequences using strong interactions with the quark model approach where each gluon which contained in quarks interact each other. But what happen if we decreased the energy level of photons in that Interactions into very low? are we can use the weak interactions model approach thats occured to the photons in the electromagnetic interactions? Is the approach to low photon energy levels we can make the gluon be like photons? Which we already know that there is a striking difference between the photon and gluon. Gluons can interact among each other with color quantum charge interactions while photons can not interact among each other. The purpose of this research is to create a model of the nucleons in the pion fotoproduksi Born Term.

Abstrak :
Mencari nilai Penampang Lintang Diferensial dan nilai Polarisasi dari Fotoproduksi Eta-Meson dengan menggunakan Model Quark. Lalu menurunkan Lagrangian Efektif untuk mencari Amplitudo. Pada Bagian akhir menggunakan penulisan Amplitudo CGLN untuk mencari nilai Amplitudo Kuadrat dan memplot grafik antara Penampang Lintang Differensial dan Sudut Hambur juga Polarisasi dan Sudut Hambur. ......Calculation of The Differential Cross Section and Polarization from Eta-Meson Photoproduction with Quark Model. After that, calculation of The Effective Lagrangian to find Amplitude. Finally, use CGLN Amplitude to find the value of Squared Amplitude and plot the graphic between Differential Cross Section and Angle, also Polarization and Angle.

Abstrak :
ABSTRAK
Telah dikaji sebuah model sederhana yang menjelaskan mekanisme kompaktifikasi dimensi dengan menggunakan medan skalar Dirac-Born-Infeld pada lima dimensi. Dengan mereduksi satu dimensi, model kita hanya akan menghasilkan vacua anti de Sitter. Investigasi pada q dimensi ekstra (q lebih dari satu) juga mendapatkan hasil anti de Sitter.

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ABSTRACT
A simple model that explains mechanism of dimensional compactification using Dirac-Born-Infeld scalar field in five dimensions has been studied. By reducing the one dimension, our model will only result in the anti de Sitter vacua. Investigation on q-extra dimensions (q more than one) also gets the result anti de Sitter vacua.

Abstrak :
[ABSTRAK
Tumbukan ion berat menghasilkan suatu kondisi dimana jumlah proton dan neutron sama, hal ini disebut symmetric nuclear matter. Pemeriksaan terhadap karakteristik SNM masih dilakukan sampai saat ini. Efek suku non linear dianggap memberikan kontribusi terhadap karakteristik dari SNM, selain itu pemeriksaan terhadap kestabilan persamaan keadaan dilakukan dengan menggunakan metode medan rerata lanjutan. Pengecekkan lanjutan terhadap kestabilan persamaan energi dilakukan dengan mengamati nilai kecepatan suara untuk setiap parameter. Solusi dari persamaan densitas skalar, potensial skalar, dan turunan pertama potensial skalar ditunjukkan oleh titik potong ketiga kurva tersebut. Selain itu, pemeriksaan efek non linear terhadap kenaikan energi ikat dan tekanan setiap kenaikan temperatur juga diperiksa. Parameter G2 yang memiliki konstanta suku cross coupling terbukti memberikan kontribusi menahan laju kenaikan energi pada SNM, hal ini diperlihatkan oleh kurva parameter G2 merupakan kurva paling soft. Kurva parameter NLZ merupakan kurva paling stiff, serta memiliki nilai Cs paling besar saat nilai massa efektif tinggi. Kestabilan persamaan energi untuk setiap parameter masih dinilai realistik, ditinjau dari nilai C2s C2 < 1, namun setiap parameter memiliki daerahketidakstabilan saat massa efektif rendah karena nilai C2s negatif.

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ABSTRACT
Heavy ion collision produces a condition where the total of proton equal with the total of the neutron this condition is named Symmetric Nuclear Matter SNM The investigation of SNM characteristic is still being done nowadays Effects of nonlinear term are considered to contribute to characteristics of SNM in addition to the examination of the stability equation of state were calculated using extended mean field method Advanced checking the stability of the energy equation is done by observing the sound velocity values each parameter The solution of scalar density equation scalar potential and first derivative of scalar potential are showed by crossing point of three curves The investigation of non linear effects to the binding energy increasing and pressure every rise of temperature G2 which has cross coupling term contributes to restrain increasing of SNM energy it is shown by the G2 parameter curve is softest NLZ is stiffest and has biggest Cs value when high effective mass condition The stability of energy equation every Heavy ion collision produces a condition where the total of proton equal with the total of the neutron, this condition is named Symmetric Nuclear Matter (SNM). The investigation of SNM characteristic is still being done nowadays. Effects of nonlinear term are considered to contribute to characteristics of SNM, in addition to the examination of the stability equation of state were calculated using extended mean field method. Advanced checking the stability of the energy equation is done by observing the sound velocity values each parameter. The solution of scalar density equation, scalar potential, and first derivative of scalar potential are showed by crossing point of three curves. The investigation of non linear effects to the binding energy increasing and pressure every rise of temperature. G2 which has cross coupling term contributes to restrain increasing of SNM energy, it is shown by the G2 parameter curve is softest. NLZ is stiffest, and has biggest Cs value when high effective mass condition. The stability of energy equation every parameter could be said mentioned realistic, it is considered from C2 s C2 < 1 value, but each parameter has instability region when low effective mass condition is happened, because the values C2 s are negative. , Heavy ion collision produces a condition where the total of proton equal with the total of the neutron this condition is named Symmetric Nuclear Matter SNM The investigation of SNM characteristic is still being done nowadays Effects of nonlinear term are considered to contribute to characteristics of SNM in addition to the examination of the stability equation of state were calculated using extended mean field method Advanced checking the stability of the energy equation is done by observing the sound velocity values each parameter The solution of scalar density equation scalar potential and first derivative of scalar potential are showed by crossing point of three curves The investigation of non linear effects to the binding energy increasing and pressure every rise of temperature G2 which has cross coupling term contributes to restrain increasing of SNM energy it is shown by the G2 parameter curve is softest NLZ is stiffest and has biggest Cs value when high effective mass condition The stability of energy equation every Heavy ion collision produces a condition where the total of proton equal with the total of the neutron, this condition is named Symmetric Nuclear Matter (SNM). The investigation of SNM characteristic is still being done nowadays. Effects of nonlinear term are considered to contribute to characteristics of SNM, in addition to the examination of the stability equation of state were calculated using extended mean field method. Advanced checking the stability of the energy equation is done by observing the sound velocity values each parameter. The solution of scalar density equation, scalar potential, and first derivative of scalar potential are showed by crossing point of three curves. The investigation of non linear effects to the binding energy increasing and pressure every rise of temperature. G2 which has cross coupling term contributes to restrain increasing of SNM energy, it is shown by the G2 parameter curve is softest. NLZ is stiffest, and has biggest Cs value when high effective mass condition. The stability of energy equation every parameter could be said mentioned realistic, it is considered from C2 s C2 < 1 value, but each parameter has instability region when low effective mass condition is happened, because the values C2 s are negative. Key words: coupling, soft, stiff. ix]

Abstrak :
ABSTRAK
Data eksperimen fotoproduksi K+ terbaru yang dikeluarkan oleh kolaborasi CLAS, LEPS, GRAAL, dan Crystal Ball akan dimodelkan yang memanfaatkan pendekatan multipole dengan menyertakan semua resonans termasuk spin tinggi 11 2 dan 13 2 . Dengan tujuan tersebut kami mengunakan diagram Feynman untuk menghitung amplitudo background dan parameterisasi Breit-Weigner untuk amplitudo resonans serta data-data resonans nukleon yang dikeluarkan oleh PDG sebagai parameter dalam perhitungan numerik. Hasil ditampilkan dalam bentuk grafik untuk semua observabel-observabel penelitian yang selanjutnya dibandingkan dengan observabel penelitian sebelumnya (Model Isobar). Hasil yang didapatkan menunjukkan model ini lebih sesuai dengan data eksperimen dilihat pada observabel penampang lintang total.

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ABSTRACT
The recently published experimental data on K+ photoproduction by the CLAS, LEPS, GRAAL, dan Crystal Ball collaborations are analyzed by using the Multipoles approach for describing all nucleon resonances, including resonances with high spin 11 2 and 13 2 . For this purpose, we use Feynman diagrams to calculate the background amplitudes, the Breit-Wigner form for resonance amplitudes and all available experimental data of nucleon resonances published by PDG, to constrain the parameters in numerical calculation. The result of our calculation is presented for all observables and compared with the previous study (Isobar Model), as well as experimental data. It is found that the present model has a better agreement with cross section experimental data.

Abstrak :
ABSTRAK
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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ABSTRACT
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.

Abstrak :
ABSTRACT
One of the simple models to address quantum many body effects in materials with impurities is Anderson Impurity Model. It describes a system consisting of non interacting conduction electrons having hybridization with a localized orbital with strong electron electron interaction at a particular site. This model has been proven successful to explain the phenomenon of metal insulator transition through Anderson localization. Despite the well understood behaviors of the model, little has been explored theoretically on how the model properties gradually evolve as functions of hybridization parameter, impurity concentration, and temperature. Here, we propose to do a theoretical study on those aspects of a single impurity Anderson model using the distributional exact diagonalization method. We solve the model Hamiltonian by randomly generating sampling distribution of a few energy levels of conduction electrons with various number of occupying electrons, starting from zero to the maximum number allowed by the available single orbital states. The resulting energy eigenvalues and eigenstates are then used to define the local single particle Green function for each sampled electron energy distribution using Lehmann representation. Later, we extract the corresponding self energy of each distribution, then average over all the distributions to obtain the final self energy of the system and construct the local Green function of the system to calculate the density of states. We repeat this procedure for various values of hybridization parameters, impurity concentrations, and temperatures. We discuss our results in connection with the criteria of the occurrence of metal insulator transition in this system.

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ABSTRACT
Salah satu model sederhana yang menunjukkan efek kuantum sistem banyak partikel pada material yang memiliki impuritas adalah Anderson Impurity Model. Model tersebut mendeskripsikan sebuah sistem yang memiliki elektron konduksi yang tidak saling berinteraksi namun mengalami hibridisasi dengan orbital yang terlokalisasi, dimana terjadi interaksi yang cukup kuat antar elektron pada orbital tersebut. Model ini terbukti berhasil menjelaskan fenomena metal-insulator transition melalui Anderson localization. Meskipun secara umum model ini telah dipahami, masih sedikit penjelasan teoretis terkait bagaimana model impuritas ini bergantung terhadap parameter hibridisasi, konsentrasi impuritas, dan suhu. Pada penelitian ini, kami mengusulkan studi teoretik mengenai pengaruh aspek-aspek tersebut terhadap single impurity Anderson model dengan menggunakan metode distributional exact diagonalization. Kami mengkontruksi Hamiltonian model ini dengan distribusi energi elektron konduksi yang acak dengan berbagai variasi jumlah elektron yang mengisi orbital sistem, berawal dari kondisi orbital kosong tidak terisi elektron sama sekali sampai jumlah maksimum yang diperbolehkan. Eigenvalue dan eigenvector yang dihasilkan dari setiap sampling digunakan untuk mendefinisikan fungsi Green orbital impuritas melalui Lehmann representation. Kemudian kami mengekstrak self-energy untuk setiap distribusi dan merata-ratakannya. Self-energy rata-rata yang diperoleh inilah yang diperlukan untuk mengkonstruksi fungsi Green total bagi elektron konduksi maupun elektron impuritas, dimana masing-masing fungsi Green tersebut digunakan untuk menghitung densitas keadaan. Kami mengulangi prosedur ini untuk berbagai variasi nilai parameter hibridisasi, konsentrasi impuritas, dan suhu. Diskusi terkait hasil penelitian yang diperoleh mengacu pada kriteria terjadinya fenomena metal-insulator transition pada sistem ini.