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TY - CONF AU - Calvey, J.R. AU - Borland, M. AU - Clute, T.K. AU - Dooling, J.C. AU - Emery, L. AU - Gagliano, J. AU - Hoyt, J.E. AU - Kallakuri, P.S. AU - Morrison, L.H. AU - Wienands, U. ED - Tavares, Daniel ED - Picoreti, Renan ED - Bruno, Gustavo ED - Marques, Sergio ED - Schaa, Volker R.W. TI - Measurements of Ion Instability and Emittance Growth for the APS-Upgrade J2 - Proc. of IBIC2020, Santos, Brazil, 14-18 September 2020 CY - Santos, Brazil T2 - International Beam Instrumentation Conference T3 - 9 LA - english AB - Ions are produced in an accelerator when the beam ionizes residual gas inside the vacuum chamber. If the beam is negatively charged, ions can become trapped in the beam’s potential, and their density will increase over time. Trapped ions can cause a variety of undesirable effects, including instability and emittance growth. Because of the challenging emittance and stability requirements of the APS-Upgrade storage ring, ion trapping is a serious concern. To study this effect at the present APS, a gas injection system was installed. A controlled pressure bump of Nitrogen gas was created over a 6m straight section, and the resulting ion instability was studied using several different detectors. Measurements were taken using a pinhole camera, spectrum analyzer, bunch-by-bunch feedback system, and a gas bremsstrahlung detector. Studies were done under a wide variety of beam conditions, and at different pressure bump amplitudes. In this paper we report on the results of some of these measurements, and discuss the implications for present and future electron storage rings. PB - JACoW Publishing CP - Geneva, Switzerland SP - 258 EP - 262 KW - emittance KW - detector KW - injection KW - photon KW - storage-ring DA - 2020/10 PY - 2020 SN - 2673-5350 SN - 978-3-95450-222-6 DO - doi:10.18429/JACoW-IBIC2020-THPP25 UR - https://www.jacow.org/ibic2020/papers/thpp25.pdf ER -