Fast losses at collimators during 16L2 dumps Arek Gorzawski & Rudiger Schmidt With a lots of inputs from: S. Redaelli, N. Fuster Martinez, H. Garcia Morales, D. Wollman, C. Xu and C. Zamantzas BLM WG 10/10/2017

Fast losses at collimators during 16L2 dumps Outline Setup of the dBLMs in IR7 Overview and observations for four loss cases Conclusions Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps System layout dBLMs in IR7 are installed at four locations: At the primary collimators (TCP), 9m downstream for B1, 8m downstream for B2 At the crystal collimators, 120m downstream for B1, 49m downstream for B2 dBLMs in 16L2 are installed at two locations, Beam1 and Beam2 Triggering of the continuous (waveform) data acquisition: At the primary collimators and 16L2, via PM event (dump trigger) 100e6 of points with 1.6ns (dead time ~1.5min) Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Case studies Fill 6094, 6.5TeV Fill 6101, 1.1TeV Fill 6173, 6.5 TeV, 8b4e Fill 6256, 6.5 TeV, 8b4e, dBLM in 16L2 Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps 17 Aug 2017 6.5 TeV Fill 6094 Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Fill 6094, 17/08 6.5 TeV, 17-AUG-2017 14.58.42.086000 6094 6499320 Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Fill 6094, 17/08 6.5 TeV, Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Fill 6094, 17/08 6.5 TeV, Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps dBLM overview Fill 6094, 17/08 6.5 TeV, Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Integrated Losses Fill 6094, 17/08 6.5 TeV, Rising slope after longer (~AG) gap Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps 19 Aug 2017 1.1 TeV Fill 6101 Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Fill 6101, 19/08 1.1 TeV, Losses from UFO Type 2 measured by BLM in 16L2 Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Fill 6101, 19/08 1.1 TeV, Protons become unstable Losses from UFO Type 2 measured by BLM in 16L2 Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Fill 6101, 19/08 1.1 TeV, Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps dBLM Loss overview Fill 6101, 19/08 1.1 TeV, 10 ms Protons become unstable 2.4 ms Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Integrated losses Fill 6101, 19/08 1.1 TeV, Rising slope after longer (~AG) gap 15 us Full beam, bunch by bunch Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Fill 6101, 19/08 1.1 TeV, 15 us 48b First few bunches of each of the 48 batch has higher losses Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps 8.9 ms 10 ms Fill 6101, 19/08 1.1 TeV, BPM PM DATA Oscillations in h-plane Increased oscillation (tune freq) in the concerned plane (Horizontal, up part) during the instability time (10ms). Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps 6 Sep 2017 6.5 TeV Fill 6173 8b4b Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Fill 6173, 6/09 6.5 TeV, 8b4e scheme Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Fill 6173, 6/09 6.5 TeV, 8b4e scheme Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Fill 6173, 6/09 6.5 TeV, 8b4e scheme Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Fill 6173, 6/09 6.5 TeV, 8b4e scheme 3 ms Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps dBLMs Overview Fill 6173, 6/09 6.5 TeV, 8b4e scheme 3 ms 100 us Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps dBLMs Overview (2) Fill 6173, 6/09 6.5 TeV, 8b4e scheme One turn 100 us Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Integrated losses Fill 6173, 6/09 6.5 TeV, 8b4e scheme Rising slope after AG + small after 30b LHC INJ gaps Full beam, bunch by bunch Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Integrated loss (2) Fill 6173, 6/09 6.5 TeV, 8b4e scheme Normalized to the sqrt(emittance) Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps 30 Sep 2017 6.5 TeV Fill 6256 8b4e Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Fill 6256, 30/90 6.5 TeV, 8b4e scheme Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Fill 6256, 30/90 6.5 TeV, 8b4e scheme Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Fill 6256, 30/90 6.5 TeV, 8b4e scheme Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps dBLMs Overview Fill 6256, 30/90 6.5 TeV, 8b4e scheme Vertical scale to be verified with BE/BI! Different connection configuration between IR7 and 16L2 Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Integrated losses Fill 6256, 30/90 6.5 TeV, 8b4e scheme dBLMs @ TCP Rising slope after AG + some 30b LHC INJ gaps dBLMs @ 16L2 Fast losses at collimators during 16L2 dumps

Fast losses at collimators during 16L2 dumps Conclusions Saturation effect in IR7 discards the data after certain threshold but the beginning of the loss reveal some observations: Observed cleaning effect (when gap > ~300bunches) Multiple loss peaks Correlation between TCP and the 16L2 losses require still some action. Amplification and attenuation difference to be clarified – to get the loss ratio Loss pattern different – no rising slope! Fast losses at collimators during 16L2 dumps