Xu, W. Ben-Zvi, I. Gao, Y. Holmes, D. Kolb, P. McIntyre, G.T. Porqueddu, R. Smith, K.S. Willeke, F.J. Wu, Q. Zaltsman, A. JACoW Publishing Geneva, Switzerland 2226-0366 978-3-95450-194-6 10.18429/JACoW-LINAC2018-THPO006 English 688-690 THPO006 cavity SRF HOM linac collider Contribution to a conference proceedings 2019 2019-01 https://doi.org/10.18429/JACoW-LINAC2018-THPO006 http://jacow.org/linac2018/papers/thpo006.pdf A 5-cell 650 MHz SRF cavity was designed for eRHIC SRF linac. One Cu cavity was fabricated for HOM damping study, and one Nb cavity was fabricated for SRF studies. Through various post-processing recipes and vertical tests, the SRF study includes high Q-value study for ERL SRF linac and high gradient study for recirculating linac. This paper reports the HOM damping measurement on the Cu cavity and preliminary vertical test results.