Integracija digitalizatorja acqiris dc-252 v kontrolni sistem epics ter implementacija algoritma za računanje življenjske dobe skupkov elektronov v sinhrotronu : magistrsko delo

Požar, Andraž (author), Bulić, Patricio (mentor)

V magistrski nalogi je bil razvit algoritem za računanje življenjske dobe skupkov elektronov v sinhrotronu SSRF in integracija le-tega v kontrolni sistem EPICS. Poznavanje življenjske dobe vsakega skupka elektronov je zelo pomemben diagnostičen parameter, ki fizikom pove veliko o kvaliteti shranjevalnega obroča sinhrotronskega pospeševalnika. Glavni problem pri razvoju rešitve je bil, da elektroni v sinhrotronu potujejo s skoraj svetlobno hitrostjo, skupki elektronov pa so dokaj kratki. Najkrajši razmak med dvema skupkoma je zgolj 2 ns, širina pulza pa le nekaj sto piko sekund. Trenutno na tržišču ni strojne opreme, ki bi lahko ob le enem prehodu skupka elektronov zajela dovolj vzorcev za zadovoljiv izračun življenjske dobe. Posledično je bilo potrebno problem rešiti na programskem nivoju ter zagotoviti dovolj dober in hiter algoritem, ki lahko v sorazmerno kratkem času računa življenjsko dobo vsakega skupka elektronov. Izračun se izvede na podlagi vzorcev zajetih preko več obhodov skupka združenih v eno valovno obliko. S to informacijo lahko fiziki in inženirji zadolženi za nadzor nad kvaliteto shranjevalnega obroča lažje razumejo kje so problemi in jih posledično lažje odpravijo.

• Language: Slovenian
• Keywords: kontrolni sistemi, EPICS, pospeševalnik delcev, fizika osnovnih delcev, življenjska doba skupkov elektronov, rekonstrukcija signala, Kalmanov filter, drseče povprečje, prileganje eksponentne funkcije
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: FRI - Faculty of Computer and Information Science
• Publisher: [A. Požar]
• Year: 2015
• Number of pages: 52 str.
• PID: 20.500.12556/RUL-73134
• COBISS.SI-ID: 1536643011
• Publication date in RUL: 21.10.2015

Secondary language

• Language: English
• Title: Integration of acqiris dc-252 digitizer into epics control system and implementation of algorithm for calculation of bunch-by-bunch lifetime in synchrotron

Abstract

In the scope of Master’s thesis, an algorithm has been developed for calculation of bunch-by-bunch lifetime in SSRF synchrotron and has been integrated into the EPICS control system. Being familiar with the lifetime of each bunch is a very important diagnostic parameter which provides a lot of information about the quality of the synchrotron storage ring to the physicists. The main obstacle in the development of the solution has been the speed electrons travel with, which is very close to the speed of light. Consequently that makes bunches to be very short. Smallest gap between two bunches is therefore only 2 ns while the width is measured in a couple of hundreds of picoseconds. The market does currently not provide equipment which could acquire a sufficient amount of samples in one passing of the bunch to calculate reliable lifetime information. Therefore, the solution had to be developed in software layer with an algorithm that is fast enough to calculate the lifetime in relatively short time. The calculation is executed based on the samples acquired over many passings of a bunch which are then combined in a single waveform. With this information, physicists and engineers in charge of quality of the storage ring can more easily understand where the problems lie and are consequently able to fix them.

• Keywords: control systems, EPICS, particle accelerator, particle physics, electron bunch lifetime, signal reconstruction, Kalman filter, sliding average, exponential function fitting