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SUMMARY:NMR-BASED INJECTION FIELD MEASUREMENT SYSTEM FOR MEDICAL PROTON SY
 NCHROTRON
DTSTART;VALUE=DATE-TIME:20220715T120000Z
DTEND;VALUE=DATE-TIME:20220715T122000Z
DTSTAMP;VALUE=DATE-TIME:20260912T195446Z
UID:indico-contribution-268@events.sinp.msu.ru
DESCRIPTION:Speakers: Mikhail Belikhin (Lomonosov Moscow State University)
 \nOne of the main processes in a proton synchrotron is capture of particle
 s during injection. For successful capture\, it is necessary to measure th
 e magnetic field in the orbit with high accuracy. Widely used Hall sensors
  have many disadvantages: not very high precision and long-term stability\
 , low radiation resistance\, angular dependence and etc. All these cause d
 ifficulties in setting of the synchrotron and reduce the stability of its 
 operation\, which is especially important for medical accelerators. Theref
 ore\, the development of new methods for control of the injection field\, 
 will improve the stability of medical synchrotrons and reduce the treatmen
 t time [1].\nThe purpose of this work is to develop a high-precision NMR-b
 ased system for measuring and controlling the injection magnetic field for
  the medical proton synchrotron [2].\nThe developed system is based on a p
 ulsed proton NMR-gaussmeter. The magnetic field measurement is made by mea
 suring the frequency of spin echoes after 180-degree pulses in Carr-Purcel
 l-Meiboom-Gill sequence. The measuring probe is installed in the vacuum ch
 amber of the synchrotron in close proximity to the injection channel. The 
 NMR-gaussmeter is built on a modern electronic element base. Control\, fre
 quency measurement and data transfer are realized by high-speed ARM-microc
 ontroller. The NMR-gaussmeter is configured and controlled using PC-softwa
 re designed in Lab Windows CVI.\nThe measuring probe provides an NMR-signa
 l from the quasi-constant synchrotron’s magnetic field of about ≈1000 
 Gs (corresponding to proton injection energy of ≈1 MeV) with the possibi
 lity of digital tuning of the resonant frequency in the range of ±50 Gs. 
 The magnetic field is measured with an accuracy of no worse than 0.1 Gs. T
 he measurement time is 20 ms. The signal-to-noise radio is at least 5.\nTh
 e developed system makes it possible to measure the injection magnetic fie
 ld in real time directly in the acceleration cycle and to ensure the stabl
 e capture of particles.\n\n1. Chernyaev A.P.\, Klenov G.I.\, Bushmanov A.Y
 .\, Pryanichnikov A.A.\, Belikhin M.A.\, Lykova E.N. Proton Accelerators f
 or Radiation Therapy // Medical Radiology and radiation safety . 2019. no.
  2. pp. 11-22.\n2. A.A. Pryanichnikov\, V.V. Sokunov\, A.E. Shemyakov\, So
 me Results of the Clinical Use of the Proton Therapy Complex «Prometheus
 »\, Physics of Particles and Nuclei Letters\, 2018\, Vol. 15 no. 7.\, P.9
 81-985.\n\nhttps://events.sinp.msu.ru/event/8/contributions/268/
LOCATION: Физический ф-т\, ауд. 5-42
URL:https://events.sinp.msu.ru/event/8/contributions/268/
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