Brookhaven Science Associates U.S. Department of Energy Todd Satogata 1 Fri May RHIC FY03 Deuteron-Gold Performance n RHIC Deuteron-Gold Performance Run Description/Chronology Performance Goals Achieved Luminosity Delivery n RHIC Performance Limitations n FY04 Au-Au Operations Projections

Brookhaven Science Associates U.S. Department of Energy Todd Satogata 2 Fri May RHIC Layout and dAu Geometries n Different species, Z/A provided new challenges in RHIC setup n Injection with both equal rigidities and equal frequencies BRAHMS/pp2pp STAR PHENIX AGS PHOBOS RF MP6MP7 Tandems Booster Pol. H - Source Linac d Au 12+ dAu 79+ foil

Brookhaven Science Associates U.S. Department of Energy Todd Satogata 3 Fri May /1Start of RHIC cooldown 12/3Blue ring at 4K, deuteron injection 12/13Deuterons accelerated to flattop; Both rings at 4K 12/22 First ramps of d/Au to collision energies 12/24First d/Au collisions at all experiments 12/27Start of routine detector commissioning 1/9Routine 110 bunch ramping 1/12Start of 2003 d/Au Physics Run 2/21Low-noise storage RF driver 2/22Deuteron transverse instability fixed 2/22First production store to hit goal levels 2/26Return to 56 bunch operations; routine goal operations 3/24End of FY03 d/Au Physics Run RHIC FY03 Deuteron-Gold Chronology

Brookhaven Science Associates U.S. Department of Energy Todd Satogata 4 Fri May RHIC FY03 Deuteron-Gold Performance Goals Storage ParameterAu, Yellow Ring Goal Achieved d, Blue Ring Goal Achieved Intensity/bunch Total Intensity Transverse Emittance [95%  rad] Bunch Length [ns] (200 MHz RF) 1.0x x x /60x x x x /69x Machine Performancegoalachieved Setup/Ramp-up time [weeks] Storage Energy [GeV/u] Number of bunches  * [m] Diamond length  [cm] 2/ / /56 2/3/4 15 Peak luminosity L [x10 28 cm -2 s -1 ] (store) [x10 28 cm -2 s -1 ] (week) [nb -1 /week] 4.0 (5.0) 1.6 (2.0) 4.0 (5.0)

Brookhaven Science Associates U.S. Department of Energy Todd Satogata 5 Fri May RHIC Deuteron-Gold Integrated Luminosity

Brookhaven Science Associates U.S. Department of Energy Todd Satogata 6 Fri May RHIC Deuteron-Gold Intensity Performance d merge n Injector dAu “mode switch” time usually 3-5 minutes, below goal

Brookhaven Science Associates U.S. Department of Energy Todd Satogata 7 Fri May RHIC Deuteron-Gold Initial Luminosities dAu operations routinely exceeded program goal performance

Brookhaven Science Associates U.S. Department of Energy Todd Satogata 8 Fri May RHIC Deuteron-Gold Typical Week

Brookhaven Science Associates U.S. Department of Energy Todd Satogata 9 Fri May RHIC Deuteron-Gold Typical Stores n 1-2 hours between stores, <5 minutes switch between d and Au n Luminosity lifetime (~4h) dominated by Au lifetime, debunching, IBS

Brookhaven Science Associates U.S. Department of Energy Todd Satogata 10 Fri May RHIC Deuteron Beam Transverse Instability n kHz-MHz transverse instabilities created emittance growth n New instrumentation provided near-immediate performance increase

Brookhaven Science Associates U.S. Department of Energy Todd Satogata 11 Fri May RHIC Beam Experiments Program n Focus on RHIC performance/upgrades, facility-driven beam physics n e.g. pressure rise/intensity limitations study (Zhang, Iriso-Ariz, Fischer,…)  Fill 1: 16 bunches+[4 empty]+..., Fill 2: 12+[8]+..., Fill 3: 14+[6]+...  Pressure rise of Fill 2 is lower than Fill 1.  Fill 3: bunch length is longer and intensity is lower. Fill 2 Fill 3 Fill 1

Brookhaven Science Associates U.S. Department of Energy Todd Satogata 12 Fri May RHIC Deuteron-Gold Performance Limitations n Vacuum pressure rise Total intensity limited to Au equivalent Limits deuteron-gold operations to 56 bunches/ring n Transition instabilities Coherent bunch oscillations drive beam growth/reduce luminosity Corrected with machine tuning Feb 23 in deuteron beam n Longitudinal instabilities Leads to factors 2–3 in diamond size, damp with “Landau cavities” n Intrabeam scattering (Au beam) Transverse/longitudinal emittance growth => electron cooling n Beam-beam tuneshift and tune spread First strong-strong hadron collider since ISR Likely present limitation to polarized proton performance

Brookhaven Science Associates U.S. Department of Energy Todd Satogata 13 Fri May RHIC FY04 Au-Au Operation Projections # bunchesIons/bunch [x10 9 ] Emittance [  rad]  * [m] L peak [cm -2 s -1 ] L ave (store) [cm -2 s -1 ] L ave (week ) [week -1 ] x x x x (ub) (ub) x x x x (ub) (ub) -1 n RHIC planning indicates a likely long FY04 Au-Au run n Almost all performance goals reached in FY03 dAu run Demonstrated  *=1m in FY02 Au-Au run, FY03 pp run Injector ramp-up time for Au intensity is indicated n Operations on possible threshold of vacuum instabilities Solenoids, bakeout, beam scrubbing are feasible solutions RHIC Retreat: June