Vertex volume isolated from YBM and XBM and being pumped with Vertex MTP backed by Inficon LD

Sprayed audible flow of helium for 25 second duration at each of the two 180 degree separated leak test slots and also slowly moved around entire joint perimeter.  LD background 9 x 10-9 torr*L/sec. Noted same joint at IP4 had visible gap -> sprayed this joint as well.  Signal crept up to 1.5 x 10-8 torr*L/sec. Signal increase was slow and not typical of metal joint leaks.  I'll notify Chandra R. of gappy joint.