February 2012 9mA Studies

21 Feb 2012, 07:00 → 27 Feb 2012, 07:00 Europe/Zurich

Universe

DESIRED MACHINE CONDITIONS * Long bunch trains (600us or more) * 3MHz bunch rep rate, range of bunch charges up to 2nC/bunch * Range of gradients on ACC67 up to cavity quench limits OVERALL GOALS * Study beam operation at maximum achievable gradients on ACC67 with light beam loading * Study setting up flat gradients on all cavities in ACC67 with heavy beam loading (continuation of ‘Pk/Q’l’ study) * Eventually: Operate as close as possible to gradient limits on ACC67 with heavy beam loading * Klystron saturation studies with heavy beam loading The nominal program for each shift is included in the notes for each shift. These will be updated as needed

Link to searchable database of DAQ channels https://ttfinfo2.desy.de/cqs/index.jsp

LLRF scaling factors for Feb 2012 LLRF_scaling_factors_2012.pdf

Tuesday 21 February

07:00 → 15:00 Morning (Maintenance)

Switch laser to 3MHz Switch machine operating rate to 5MHz

Notes from daily coordination meeting 9mAStudiesCoordination_Tuesday21Feb.docx

15:00 → 23:00 Afternoon

TPS validation Machine setup for long bunch trains at 3MHz and 5Hz Energy: 1GeV

23:00 → 07:00 Night

Machine tuning: aim for ≥1nC/bunch at 3MHz, 600us bunch trains

Wednesday 22 February

07:00 → 15:00 Morning

Beam loading compensation setup Piezo tuner setup Measurements of ACC67 quench limits

Notes from daily coordination meeting 9mAStudiesCoordination_Wed22Feb.docx

15:00 → 23:00 Afternoon

Pk/Ql studies at ≥3mA

Pk/Ql shift summary shift summary

23:00 → 07:00 Night

1. Continue Pk/Ql studies at 3mA/600us as needed 2. Injector matching for 2nC bunches, starting around 04:00 3. Parasitically, perform initial gradient limit measurements

Thursday 23 February

07:00 → 15:00 Morning

1. Once injector matching is completed at 2nC, begin transporting 2nC bunches and long bunch trains to the end of the linac 2. Return to high gradient studies: measure gradient limits without beam, then measure with light beam loading

Quench shift summary shift summary

15:00 → 23:00 Afternoon

Preparation for Klystron saturation / RF power overhead studies Pk/QL studies at ≥4mA

23:00 → 07:00 Night

Machine tuning: aim for 2nC/bunch @ 3MHz, 600us bunch trains

Friday 24 February

07:00 → 15:00 Morning

Test procedures for performing gradient scans (+/- few %) with 6mA and 600us bunch trains

Pk/Ql shift summary shift summary

15:00 → 23:00 Afternoon

High gradient studies with light beam loading

Quench shift summary 2012_02_24_-_late_shift_-_Quench_gradient_study.docx

23:00 → 07:00 Night

Pk/Ql studies at 6mA and long bunch trains Set up for 8hr stable run with gradients close to quench and moderate beam loading

Saturday 25 February

07:00 → 15:00 Morning

8hr stable run with high gradients and beam loading

15:00 → 23:00 Afternoon

High gradient studies Set up for RF power overhead studies

23:00 → 07:00 Night

RF power overhead studies

document Preliminary summary

Near kly. saturation Near kly. saturation

Sunday 26 February

07:00 → 15:00 Morning

Set up high gradient studies with heavy beam loading High gradient studies with heavy beam loading

15:00 → 23:00 Afternoon

High gradient studies with heavy beam loading

23:00 → 07:00 Night

High gradient studies with heavy beam loading