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Brookhaven Science AssociatesU.S. Department of Energy
Todd Satogata 1 Fri May 16 2003
RHIC FY03 Deuteron-Gold PerformanceRHIC FY03 Deuteron-Gold Performance
RHIC Deuteron-Gold Performance• Run Description/Chronology• Performance Goals Achieved• Luminosity Delivery
RHIC Performance Limitations FY04 Au-Au Operations Projections
http://www.rhichome.bnl.gov/AP/RHIC2003
Brookhaven Science AssociatesU.S. Department of Energy
Todd Satogata 2 Fri May 16 2003
RHIC Layout and dAu GeometriesRHIC Layout and dAu Geometries
Different species, Z/A provided new challenges in RHIC setup Injection with both equal rigidities and equal frequencies
BRAHMS/pp2pp
STARPHENIX
AGS
PHOBOS
RF
MP6 MP7Tandems
BoosterPol. H- Source
Linac
d Au12+
d Au79+
foil
Brookhaven Science AssociatesU.S. Department of Energy
Todd Satogata 3 Fri May 16 2003
11/1 Start of RHIC cooldown12/3 Blue ring at 4K, deuteron injection12/13 Deuterons accelerated to flattop; Both rings at 4K12/22 First ramps of d/Au to collision energies12/24 First d/Au collisions at all experiments12/27 Start of routine detector commissioning1/9 Routine 110 bunch ramping1/12 Start of 2003 d/Au Physics Run2/21 Low-noise storage RF driver2/22 Deuteron transverse instability fixed2/22 First production store to hit goal levels2/26 Return to 56 bunch operations; routine goal operations3/24 End of FY03 d/Au Physics Run
RHIC FY03 Deuteron-Gold ChronologyRHIC FY03 Deuteron-Gold Chronology
Brookhaven Science AssociatesU.S. Department of Energy
Todd Satogata 4 Fri May 16 2003
RHIC FY03 Deuteron-Gold Performance GoalsRHIC FY03 Deuteron-Gold Performance Goals
Storage Parameter Au, Yellow Ring Goal Achieved
d, Blue Ring Goal Achieved
Intensity/bunchTotal IntensityTransverse Emittance [95% rad]Bunch Length [ns] (200 MHz RF)
1.0x109 0.7x109
55x109 38/60x109 10-40 10-30 5 5
0.8x1011 1.1x1011 45x1011 57/69x1011 15 12 5 5
Machine Performance goal achieved
Setup/Ramp-up time [weeks]Storage Energy [GeV/u]Number of bunches* [m]Diamond length [cm]
2/310056220
2.5/3 100
110/56 2/3/4
15 Peak luminosity L [x1028 cm-2 s-1]<L>(store) [x1028 cm-2 s-1]<L>(week) [nb-1/week]
4.0 (5.0)1.6 (2.0)4.0 (5.0)
7.2 2.2 4.6
Brookhaven Science AssociatesU.S. Department of Energy
Todd Satogata 5 Fri May 16 2003
RHIC Deuteron-Gold Integrated LuminosityRHIC Deuteron-Gold Integrated Luminosity
Brookhaven Science AssociatesU.S. Department of Energy
Todd Satogata 6 Fri May 16 2003
RHIC Deuteron-Gold Intensity PerformanceRHIC Deuteron-Gold Intensity Performance
55110
d merge
Injector dAu “mode switch” time usually 3-5 minutes, below goal
Brookhaven Science AssociatesU.S. Department of Energy
Todd Satogata 7 Fri May 16 2003
RHIC Deuteron-Gold Initial LuminositiesRHIC Deuteron-Gold Initial Luminosities
dAu operations routinely exceeded program goal performance
Brookhaven Science AssociatesU.S. Department of Energy
Todd Satogata 8 Fri May 16 2003
RHIC Deuteron-Gold Typical WeekRHIC Deuteron-Gold Typical Week
Brookhaven Science AssociatesU.S. Department of Energy
Todd Satogata 9 Fri May 16 2003
RHIC Deuteron-Gold Typical StoresRHIC Deuteron-Gold Typical Stores
1-2 hours between stores, <5 minutes switch between d and Au Luminosity lifetime (~4h) dominated by Au lifetime, debunching, IBS
Brookhaven Science AssociatesU.S. Department of Energy
Todd Satogata 10 Fri May 16 2003
RHIC Deuteron Beam Transverse InstabilityRHIC Deuteron Beam Transverse Instability
kHz-MHz transverse instabilities created emittance growth New instrumentation provided near-immediate performance increase
Brookhaven Science AssociatesU.S. Department of Energy
Todd Satogata 11 Fri May 16 2003
RHIC Beam Experiments ProgramRHIC Beam Experiments Program
Focus on RHIC performance/upgrades, facility-driven beam physics 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 AssociatesU.S. Department of Energy
Todd Satogata 12 Fri May 16 2003
RHIC Deuteron-Gold Performance LimitationsRHIC Deuteron-Gold Performance Limitations
Vacuum pressure rise• Total intensity limited to 100-110 109 Au equivalent• Limits deuteron-gold operations to 56 bunches/ring
Transition instabilities• Coherent bunch oscillations drive beam growth/reduce luminosity• Corrected with machine tuning Feb 23 in deuteron beam
Longitudinal instabilities• Leads to factors 2–3 in diamond size, damp with “Landau
cavities” Intrabeam scattering (Au beam)
• Transverse/longitudinal emittance growth => electron cooling Beam-beam tuneshift and tune spread
• First strong-strong hadron collider since ISR• Likely present limitation to polarized proton performance
Brookhaven Science AssociatesU.S. Department of Energy
Todd Satogata 13 Fri May 16 2003
RHIC FY04 Au-Au Operation ProjectionsRHIC FY04 Au-Au Operation Projections
# bunches Ions/bunch[x109]
Emittance[rad]
*[m]
Lpeak
[cm-2 s-1]Lave(store)[cm-2 s-1]
Lave(week)[week-1]
56 1.0 15-40 13
14.0x1026
4.7x1026
3.0x1026
1.0x1026
70.0 (ub)-1
23.3 (ub)-1
56 0.7 15-40 13
7.0x1026
2.4x1026
1.5x1026
0.5x1026
35.0 (ub)-1
11.7 (ub)-1
RHIC planning indicates a likely long FY04 Au-Au run 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
Operations on possible threshold of vacuum instabilities• Solenoids, bakeout, beam scrubbing are feasible solutions
RHIC Retreat: June 10-12 2003