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TY - CONF AU - Mallick, C. AU - Bandyopadhyay, M. AU - Kumar, R. ED - Yamazaki, Yoshishige ED - Raubenheimer, Tor ED - McCausey, Amy ED - Schaa, Volker RW TI - Transverse Ion Beam Emittance Growth Due to Low Frequency Instabilities in Microwave Ion Source Plasma J2 - Proc. of NAPAC2019, Lansing, MI, USA, 01-06 September 2019 CY - Lansing, MI, USA T2 - North American Particle Accelerator Conference T3 - 4 LA - english AB - The ion source is accompanied by the generation of low frequency (LF) plasma instabilities (PI). Its signature is also visible in high current heavy ion beam required for any accelerator. These LFs affect the profile of the ion beam in transverse phase-space. These issues are investigated in detail by measuring the emittance of beam. Beam oscillations are extracted from the transverse emittance data by taking Fast Fourier Transform (FFT) of it. PI frequencies are identified in the measured electromagnetic emission from the plasma, in which these frequencies appeared as sidebands around pump frequency 2.45 GHz. The PI components i.e.,ion acoustic (IA) and ion cyclotron (IC) waves are also visible in the FFT spectra. Low and high frequency oscillations in the beam are 476 kHz and ~1.3 MHz respectively. These two groups of frequencies also exist within the PI induced IA (238 - 873 kHz) and IC (1.29 - 1.3 MHz) frequency ranges. The measured emittance (rms-normalized) in horizontal and vertical phase-space varies from 0.002-0.098 𝜋 mm mrad and 0.004-0.23 𝜋 mm mrad respectively. PI induced beam oscillation is the reason behind such broad transverse emittance growth. PB - JACoW Publishing CP - Geneva, Switzerland SP - 363 EP - 367 DA - 2019/10 PY - 2019 SN - 2673-7000 SN - 978-3-95450-223-3 DO - doi:10.18429/JACoW-NAPAC2019-TUZBB5 UR - http://jacow.org/napac2019/papers/tuzbb5.pdf ER -