Частотная и фазовая модуляция гармонического питания квадрупольного фильтра масс
Sorry, this entry is only available in Русский.
Квадрупольный фильтр масс с малой низкочастотной временной гармоникой электрического поля
Upper stability island created by auxiliary RF voltage with small amplitude and low frequency ν = ω/Ω = 1/10 is investigated. The possibility of operation of quadrupole mass fi lter with high transmission 50 % and high resolution about R0.1 = 3000 is demonstrated. Phase shift synchronization, ion cooling by buffer gas in RF quadrupole, and time fl ight through fringing fi eld optimization are required for achievement of such parameters.
Resolution, Peak Shape and Transmission
T8N3
Разрешающая способность, форма пика
и коэффициент пропускания квадрупольного
фильтра масс с амплитудной модуляцией
высокочастотного напряжения
Евгений Яковлевич Черняк, Николай Витальевич Конёнков,
Александр Николаевич Корольков, Алексей Сергеевич ПоляковРязанский государственный университет им. С.А. Есенина,
Россия, 390000, Рязань, ул. Свободы, 46,
E-mail: n.konenkov@rsu.edu.ru
Resolution improvements in a round-rod quadrupole mass filter (QMF) by means of amplitude modulation of the applied RF voltage have been examined using numerical modeling. Simulations show that at a given transmission (40 %) and defined ion source emittance, the resolution reaches a maximum (1900) when the modulation relative frequency n = 1/2 (n = (modulation frequency)/(quadrupole radio frequency)). With low (n = 1/10) and high (n = 9/10) modulation frequencies, the QMF operation is characterized by good resolution and peak shape at low separation times (about 100 RF cycles) when cylindrical electrodes are used.