Скачать презентацию DAΦNE performances during the KLOE-2 data-taking Catia Milardi Скачать презентацию DAΦNE performances during the KLOE-2 data-taking Catia Milardi

f72e4b2e963d3d9633d28029d783852f.ppt

  • Количество слайдов: 24

DAΦNE performances during the KLOE-2 data-taking Catia Milardi on behalf of the DAFNE Team DAΦNE performances during the KLOE-2 data-taking Catia Milardi on behalf of the DAFNE Team CSN 1 Meeting Florence 20 -21 Jul 2015

Contents • The KLOE-2 data taking • Latest luminosity achievements • Future program • Contents • The KLOE-2 data taking • Latest luminosity achievements • Future program • Conclusions

DAFNE and KLOE-2 ECM = 1020 Me. V Colliding beams have: low E high DAFNE and KLOE-2 ECM = 1020 Me. V Colliding beams have: low E high currents long damping time Luminosity achieved at DAFNE is 2 order of magnitude higher than the best measured in colliders working at the same E

KLOE-2 Data Taking Program On past fall the KLOE-2 data taking program has been KLOE-2 Data Taking Program On past fall the KLOE-2 data taking program has been presented (Catania meeting) The main point of that program established the collider had to deliver to the experiment 1 fb-1 in eight operation months

KLOE-2 Data Taking (2014 ÷ 2015) Nov 17 th Dec 26 th Feb 4 KLOE-2 Data Taking (2014 ÷ 2015) Nov 17 th Dec 26 th Feb 4 th Mar 16 th Apr 25 th Jun 4 th

Peak Luminosity 103 bunches L∫ 1 hour = 0. 54 pb-1 DA NE CW Peak Luminosity 103 bunches L∫ 1 hour = 0. 54 pb-1 DA NE CW upgrade DA NE (CW) SIDDHARTA (2009) Lpeak [cm-2 s-1] DA NE KLOE (2005) KLOE-2 (2014) 4. 53 • 1032 1. 50 • 1032 2. 0 • 1032 I- [A] 1. 52 1. 4 1. 03 I+ [A] 1. 0 1. 2 1. 03 Nbunches 105 111 103 Lpeak exceeds by a 33% the best luminosity ever achieved, at DAFNE, during operations for an experimental apparatus including high field detector solenoid. Background presently has been considerably reduced especially the component due to the e- beam

Machine Developments Machine developments have been limited to very few aspects in favour of Machine Developments Machine developments have been limited to very few aspects in favour of the experiment data taking § Number of colliding bunches have been increased in the range 93 ÷ 103 maintaining almost the same total current thus reducing: • Touschek contribution to background • Impact of microwave instability threshold § A new working point has been adopted for the MRe § Extensive adiabatic collider optimization & luminosity fine tuning

Best Weekly ∫L Best week so far (20 ÷ 27 April 2015) Best Weekly ∫L Best week so far (20 ÷ 27 April 2015)

Best Monthly ∫L performances (Nov) (Dec) (Jan) (Feb) (Mar) (Apr) ∫ L ~ 251 Best Monthly ∫L performances (Nov) (Dec) (Jan) (Feb) (Mar) (Apr) ∫ L ~ 251 pb-1 ∫ L ~ 210 pb-1 del acq Apr 15 th ∫Ldel = Apr 20 th pb-125 th Apr 30 th th ÷ May 10 thth 271. 2 Apr (April 11 May 5 th May 10 )

Expected ∫L in the next year Assuming: ∫L ~ 250 pb-1 per month 8 Expected ∫L in the next year Assuming: ∫L ~ 250 pb-1 per month 8 months of operations (10 months foreseen by now) It’s reasonable to expect a delivered integrated luminosity of the order of; ∫L ~ 2 fb-1 per year This is possible only in the case the effort in terms of scientific and technical manpower will be kept, at least, constant

DAFNE manpower In the last year the DAFNE scientific staff lost four people two DAFNE manpower In the last year the DAFNE scientific staff lost four people two of them senior scientists Due to new project becoming more and more demanding the involvement of several colleagues decreased considerably Since July four expert Technicians retired and left the Operation Group No new entry

Further Developments Beam Physics A considerably higher luminosity might be attained by: • betatron Further Developments Beam Physics A considerably higher luminosity might be attained by: • betatron coupling optimization • CW-Sextupoles allignment • Pushing the microwave instability threshold toward higher current by new optics configuration (higher ac) • Feedback noise reduction • Tuning the interplay between RF 0 -mode feedback and longitudinal feedback Systems development and consolidation Operation efficiency requires at least to • • Complete the Control System upgrade Improve diagnostics Replace the Compressor of the Cryo plant (next Winter holiday) Plan regular and extensive maintenance interventions

Conclusions DAFNE performances are evolving in a positive direction: • operation is more stable Conclusions DAFNE performances are evolving in a positive direction: • operation is more stable and reproducible • peak and integrated luminosity are growing • background due to the e- beam has been recently reduced by a 20% There are many ideas to further improve the present situation The KLOE-2 data-taking is going on and, despite some breaks, agreements have been honoured ∫L ~ 1 fb-1 has been already delivered Uptime and reliability of the DAFNE subsystems are improving, but still require attention, work and some investment Manpower is still a concern

Thank you for your attention Thank you for your attention

RF Klystron replacement The Klystron of the RF cavity on the electron ring has RF Klystron replacement The Klystron of the RF cavity on the electron ring has been: • removed • replaced with a spare part already mended in house • conditioned • damaged klystron has been repaired in the DAFNE hall After 10 days 1. 6 A have been stored in a stable e- beam

STOP scheduled accidental fault Cryo Plant maintenance KLOE activities Radio Protection Voltage Dip Energy STOP scheduled accidental fault Cryo Plant maintenance KLOE activities Radio Protection Voltage Dip Energy provider fault Linac (mod. C) LNF network Klystron of the MRe RF KLOE PS cooling CS upgrade & Cooling System Operation Course Winter Holiday Radio Protection Voltage Dip LNF network Voltage Dip Collider downtime • Only events interrupting machine operation for more than half day are reported • Minor faults are usually recovered in few hours and their impact on operation can be deduced from UPTIME plots

Weekly performance Weekly performance

Monthly performances (Nov) (Dec) (Jan) (Feb) (Mar) (Apr) ∫Ldel = 271. 2 pb-1 (April Monthly performances (Nov) (Dec) (Jan) (Feb) (Mar) (Apr) ∫Ldel = 271. 2 pb-1 (April 11 th ÷ May 10 th)

Working Point Studies Lifetrack is a fully symplectic 6 D weak – strong simulation Working Point Studies Lifetrack is a fully symplectic 6 D weak – strong simulation code allowing for simulations including: • non-linearities • coupling • chromaticity • beam-beam • large crossing angle • beam crabbing The code provides: 3 D density of weak beam specific luminosity and beam lifetime DA and FMA HL-LHC LARP

e+ Working Point Scan Luminosity e+ Inverse beam sizes Qx=0. 0980; Qy=0. 1305 MRp e+ Working Point Scan Luminosity e+ Inverse beam sizes Qx=0. 0980; Qy=0. 1305 MRp was already close to the optimal WP

e- Working Point Scan Luminosity FMA Qx=0. 088 Qy=0. 152 Inverse beam sizes FMA e- Working Point Scan Luminosity FMA Qx=0. 088 Qy=0. 152 Inverse beam sizes FMA Qx=0. 130 Qy=0. 170 MRe was moved to the optimal WP Qx=0. 135 Qy=0. 17 obtaining: improved injection efficiency higher beam lifetime Reduced background higher luminosity

Cryogenic plant T 1 C All started with an anomalous DPT 1 -C ~ Cryogenic plant T 1 C All started with an anomalous DPT 1 -C ~ 3 b (Jan 2014) KLOE solenoid warmed up and cleaned (Aug 2014) Since Spt 2014: • some air leakage found and fixed after extensive checks • seal of the compressor screw replaced • oil contamination detected before the cold box first turbine imposing washing the Cold Box circuit by acetone • oil contamination in the gas management system -> washing Technical assistance and support from Linde