Koivisto, H. A. Kalvas, T. Kronholm, R.J. Tarvainen, O.A. JACoW Publishing Geneva, Switzerland 978-3-95450-196-0 10.18429/JACoW-ECRIS2018-MOA3 English 1-4 MOA3 ECR plasma ion-source permanent-magnet extraction Contribution to a conference proceedings 2019 2019-01 https://doi.org/10.18429/JACoW-ECRIS2018-MOA3 http://jacow.org/ecris2018/papers/moa3.pdf A new 18 GHz ECR ion source HIISI is under commissioning at the Accelerator Laboratory at the University of Jyväskylä (JYFL). The main purpose of HIISI is to produce high-energy beam cocktails, e.g. Xe⁴⁴⁺, for radiation effects testing of electronics, and high intensity ' 5 MeV/u ion beams for international nuclear physics program with the K130 cyclotron. The initial commissioning results in 18+14 GHz operation mode using 24 segment sextupole (1.3 T) were performed in autumn 2017. In the beginning of 2018 a stronger 36 segment sextupole (1.45 T) was constructed. The first tests have been performed during the spring 2018 demonstrating improved performance of HIISI. As an example, the intensity of 0.5 mA was reached for the Ar¹²⁺ ion beam at the extraction voltage of 16 kV and total microwave power of about 2.5 kW. In this article we will present the latest development work, ion beam intensities of oxygen, argon and xenon, and future prospects of HIISI.