September 15th 2009Olympus technical review at DESY, F.Brinker1 DORIS storage ring Olympus in the IP-region Beam optic, changes on the lattice Beam dimensions, Target cell Synchrotron Radiation Beam acceleration, Particle polarity Machine studies

September 15th 2009Olympus technical review at DESY, F.Brinker2 Geometry of the detector and the IP-region

September 15th 2009Olympus technical review at DESY, F.Brinker3 View to the IP-region from outside with ARGUS on the left side

September 15th 2009Olympus technical review at DESY, F.Brinker4 Top view with radiation shielding

September 15th 2009Olympus technical review at DESY, F.Brinker5 Straight section from the arc to the IP Vertical scraper Horizontal scraper Main source of synchrotron radiation beam direction

September 15th 2009Olympus technical review at DESY, F.Brinker6 New optic with a reduced beam size at the IP : from σ x x σ z = 3.7 x 0.7 mm 2 to 1.1 x 0.3 mm 2 Due to the asymmetry of the detector the target cell is not at the IP but at about 0.75 m Optical functions at the insertion devices and injection are kept nearly unchanged

September 15th 2009Olympus technical review at DESY, F.Brinker7 Energy [GeV] Max Beam Current [mA]140 Target cell27 mm x 9 mm Beta-x IP< 2.7 m Beta-z IP< 1.5 m Lifetime≈ 0.7 h Energy acceptance> 0.8% hor. Emittance [nm] hor. Dispersion at IP [m]-0.5 hor. beamsize (1) at Target[mm] vert. Emittance (5% coupl.) [nm] vert. beamsize (1) at Target[mm] energy spread (1) [%] hor. damping time [ms] vert. damping time [ms] long. damping time [ms] Main Parameter

September 15th 2009Olympus technical review at DESY, F.Brinker8 Horizontal Acceptance and Beam sizes at 4.5 and 2.3 GeV The acceptance is defined by the existing aperture limitations and limits the extend of any beam halo

September 15th 2009Olympus technical review at DESY, F.Brinker9 vertical Acceptance and Beam sizes at 4.5 and 2.3 GeV

September 15th 2009Olympus technical review at DESY, F.Brinker10 Vacuum system current position to be removed new position current position new position valves Adapter chambers

September 15th 2009Olympus technical review at DESY, F.Brinker11 Synchrotron Radiation [B.Nagorny, A.Schmidt] Energy [GeV] Power through Target [W] Photons through target [1/sec]1.4E163.0E16 Power on fixed collimator [W] Photon on fixed collimator [1/sec]4.4E169.7E16 Critical energy [keV] About 60% of this could be shielded by the movable scaper stations

September 15th 2009Olympus technical review at DESY, F.Brinker12 Synchrotron radiation at 4.5 GeV - dipole W/cm² Linear power density: 24 W/cm x [cm] y [cm]

September 15th 2009Olympus technical review at DESY, F.Brinker13 Injection for DORIS III and PETRA III For OLYMPUS particle beams with electrons and positrons are needed with energies of 2.0 to 2.3 GeV The Linac, PIA and DESY are able to deliver both particles. The energy of the DESY synchrotron varies sinusoidal with a maximum energy of up to 7 GeV The extraction energy is defined by the peak energy and the timing of the extraction within the energy cycle. Both are variable. Modifications are needed for fast switching of the magnet polarity of DORIS and the transport. 450 MeV Linac: Gun delivers electrons, which can be converted to positrons after half of the linac PIA : accumulation of several linac pulses to increase the bunch current DESY : 12.5 Hz / 7 GeV Synchrotron – a trigger generator allows the extraction at different energies to either Doris or Petra

September 15th 2009Olympus technical review at DESY, F.Brinker14 Machine studies on February 7 th Injection into 10 bunches Final current 170 mA after 6 minutes Varying efficiency – probably due to effects at DESY: DESY operated at normal maximum energy of 4.5 GeV At 2.3 GeV the beam is not fully damped to its equilibrium emittance Possibly beam blow up due to resonances

September 15th 2009Olympus technical review at DESY, F.Brinker15 Machine studies on February 7 th Stored beam with good conditions: I = 150 mA Lifetime = 8.5 hours Not so nice: Longitudinal beam excitation (oscillation with ~1cm Amplitude) Limits lifetime at higher currents maybe increased particle background

September 15th 2009Olympus technical review at DESY, F.Brinker16 Machine shift Aug. 3 rd Beam intensity limited to 120 mA in 10 Bunches, long. stable

September 15th 2009Olympus technical review at DESY, F.Brinker17 Machine shift Sept. 9 th 90%+ injection efficiency, 30 mA injected in 2 min.

September 15th 2009Olympus technical review at DESY, F.Brinker18 Sept. 9 th, horizontal scraper measurements beam core - gaussian profile region of beam halo halo ends at ≈ 19mm since the horizontal beam size at the IP is about a factor 2 smaller, the beam halo would extend to ± 10 mm from beam center results are preliminary, the scraper position has to be verified!

September 15th 2009Olympus technical review at DESY, F.Brinker19 Sept. 9 th, horizontal scraper measurements beam core - gaussian profile region of beam halo halo ends at ≈ 5.5 mm since the vertical beam size at the IP is about a factor 3 smaller, the beam halo would extend to ± 1.8 mm from beam center results are preliminary, the scraper position has to be verified!

September 15th 2009Olympus technical review at DESY, F.Brinker20 topics for further studies: stabilize ejection from synchrotron / improve transfer efficiency find optimal working point for tunes experiences with second long. feedback amplifier (installation at end of September) investigate max. stable beam current (presently 120mA) tests at 2.0 GeV

September 15th 2009Olympus technical review at DESY, F.Brinker21 Infrastructure Detector power supply Detector cooling Polarity switches Kicker pulser Preparation of the experimental hall Modification of the IP region Installation of Olympus

September 15th 2009Olympus technical review at DESY, F.Brinker22 Detector power supply A 10kV to 480V transformer is available and will be placed outside the experimental hall The foundation has to be prepared The 7000 A power supply from Petra has to be installed in the hall The cabling to the transformer (10kV), to the power supply (2500A, 480V DC) and to the detector (7000A, 225V DC) has to be done mainly by an external company

September 15th 2009Olympus technical review at DESY, F.Brinker23 Water cooling of toroid The capacity of the cooling tower is sufficient The cooling water circuit to ARGUS is still available It’s now in use for the cooling of transport line magnets The capacity of the circuit is sufficient for Olympus after smaller modifications ( 20 m of new tubes with larger cross section ) The two installed pumps have to run in parallel The pressure has to be reduced from 12 bar to 5 bar Cooling for the moved cavities is still available, the last few meters are missing Cold water for air conditioning is also available, tubes have to be laid

September 15th 2009Olympus technical review at DESY, F.Brinker24 Trans- former Water cooling Power- supply Electronics hutch

September 15th 2009Olympus technical review at DESY, F.Brinker25 Polarity switches There are 46 main magnet power supplies at DORIS and the transport line 12 of those are already replaced by bipolar devices 10 devices with currents below 270A can be modified with polarity switches from HERA The remaining 24 devices need new polarity switches, 14 devices for 400A and 10 devices for 800A Cabinets, controls and cabling have to be done

September 15th 2009Olympus technical review at DESY, F.Brinker26 Kicker pulser The extraction/injection elements at DESY and DORIS have to be bipolar The Septa can be modified accordingly The Kicker ( 2 DORIS + 1 DESY ) need new power supplies and new pulsers which would be build at DESY

September 15th 2009Olympus technical review at DESY, F.Brinker27 Preparation of the experimental hall Part of the hall is in use for an DESY exhibition, these objects will be removed and partly find a new home in HERA hall west The ARGUS detector will be disassembled and removed This work will start soon and should be finished by the end of this year

September 15th 2009Olympus technical review at DESY, F.Brinker28 Modification RF-lab An RF laboratory for testing of Tesla cavities is placed on the outside of the DORIS ring A rectangular region of 2.5 x 9.5 m has to be cut out –Install dust cover –Remove walls –Cut ceiling and floor –Build new walls –Change installations ( crane, electricity, water etc.) This work can start in summer 2010, when the ongoing work in the laboratory is finished (earlier, if possible)

September 15th 2009Olympus technical review at DESY, F.Brinker29 Modification of the IP region (1. shut down in winter 2010/11) Move signal cables from IP region ( can be done in advance ) Remove interlock installations Remove shielding blocks Remove accelerator components –Cavities, vacuum chambers –4 quadrupoles –Girders Install dust cover Demolition work on parts of concrete

September 15th 2009Olympus technical review at DESY, F.Brinker30 Modification of the IP region, cont. Build up new shielding Install new girders/support for experiment vacuum Put in 6 new quadrupoles Install vacuum system, including target chamber and new vacuum valves Install cavities at the new position Cabling, water connections Install modified interlock system Surveying

September 15th 2009Olympus technical review at DESY, F.Brinker31 Installation of Olympus ( 2. shut down in summer 2011 ) Remove part of shielding Remove vacuum system between valves Roll in the detector Install vacuum chambers Connect cooling water and electrical power Rebuild shielding Surveying Interlock tests

September 15th 2009Olympus technical review at DESY, F.Brinker32 Summary The space for the detector is still available Some modifications to the storage ring are necessary – but no “show-stoppers” are visible A beam optic has been developed which should work for synchrotron radiation runs as well as for OLYMPUS The most time consuming work takes place outside the Doris tunnel and needs no shutdown time The modifications of the IP region can be done within 2 shutdown periods The infrastructure for the experiment can be provided to a large extend with available equipement The effort to realize the experiment is significant, but it’s only a small fraction of what’s already available.