# Presentation: 258085

## Status and Evolution of the RHIC Facility

*Steve Vigdor*
*Quark Matter 2008*
*Jaipur, India*

**Long-Term Science Goals**
**Recent Performance**
**Fast-Tracking RHIC-II with Stochastic Cooling**
**Other Mid-Term Machine Upgrades**
**Detector Upgrades**
**Five-Year Outlook**
**Path to eRHIC**

**Notes:**
Start with a safety Topic

## RHIC / RHIC-II / e-RHIC  Laboratory Dedicated to Exploration of Condensed Strongly Interacting Matter

***RHIC / RHIC-II / e-RHIC ************ Laboratory Dedicated to Exploration of Condensed Strongly Interacting Matter***

**What are the unique quantum many-body manifestations of a non-Abelian gauge theory?  Are there lessons for other fundamental theories?  How do we pump/probe partonic matter in 10********23**** s?**

**RHIC, RHIC-II probe very strong coupling limit:  LQCD ******** quantitative theory for static properties; AdS/CFT ******** qualitative insight + gravity connection.**

**e-RHIC probes weak coupling regime of very high gluon density, where gauge boson occupancy >> 1 & semi-classical field theory apply.**

**... ****to the**

## Complementary Role as Unique Polarized Collider to Explore Nucleon Spin Structure 

***Complementary Role as Unique Polarized Collider to Explore Nucleon Spin Structure ***

## Improved Collision Luminosity 2006-8

***Improved Collision Luminosity 2006-8***

**10**

**50**

**40**

**30**

**20**

**0**

*** ******Delivered luminosity each year has come close to maximum projected***
*** ******Full energy Au+Au in 2007 already exceeded RHIC design goal luminosity***
*** ******Another factor ~3 over 2006 ******L****** needed to reach enhanced pp design goal***
*** ******d+Au completed in 2008 ************ x 30 over previous ************ ******L ******dt; starting 6-week p+p run***

## Improved Proton Polarization

***Absolute P******beam****** calibrated to  < ************ 5% ***

***Significant learning curve with unique & complex polariza-tion-preserving equipment in AGS & RHIC***

*** ******60% beam polarization achieved reliably in 2006, compared to 70% goal***
*** ******Absolute calibration of beam polarization to better than design goal accuracy achieved***
*** ******Polarization survival to 250 GeV maximum energy demonstrated***

## Important New Results Emerging In Spite of Issues from Congressional Budgeting Process

**2006 polarized proton run (with some funding from Renaissance Technologies) ******** RHIC spin program zeroing in on ****gluon contribution to proton spin!**
****** “****missing spin” puzzle remains unsolved for the moment ...**

***Important New Results Emerging In Spite of Issues from Congressional Budgeting Process***

*** ******Extensive Au+Au results from 2007 run presented by RHIC experiments at this Quark Matter***
*** ******d+Au data from excellent 2008 performance should test gluon saturation predictions, e.g., for mono-jets at large rapidity -- see QM09! ***

## RHIC-II Science: Quantifying Properties of the Perfect Liquid

***RHIC-II Science: Quantifying Properties of the Perfect Liquid***

## RHIC-II Science: Quantifying Properties of the Perfect Liquid

***RHIC-II Science: Quantifying Properties of the Perfect Liquid***

**Facilitate rare- and multi-particle correlation measurements: ******** + jet to quantify energy loss transport coefficient; multi-hadron to study possible Mach cone, extract speed of sound.**
**Improve exp’t-theory comparison of particle-identified (esp. heavy quark) flow, to quantify **

**	****                     ****shear viscosity.**
**Improve fluctuation measure-ments at low collision E to search for QCD critical point.**

***LHC and RHIC-II HI results should be complementary & mutually stimulating: similar matter produced? How do properties evolve? Thermalization consistent?***
***Quantitative interpretation of both requires coherent theory assault!***

## RHIC Stochastic Cooling Breakthrough  Fast Track to Luminosity Upgrade

***RHIC Stochastic Cooling Breakthrough ************ Fast Track to Luminosity Upgrade***

***First successful demo of stochastic cooling for bunched beams relied on state-of-art multi-GHz HV kicker and filtering out coherent bunch motion.***

***2007 implementation for longitudinal cooling of yellow beam demonstrated ability to reduce intrabeam scattering effect on luminosity lifetime.***

## Plan to Implement and Test Stochastic Cooling of Heavy Ion Beams at RHIC            (submitted to DOE 12/31/07)

***Plan to Implement and Test Stochastic Cooling of Heavy Ion Beams at RHIC            ****(submitted to DOE 12/31/07)*

*** ******Test combined effect of long. & transverse stochastic cooling for one beam in 2009 run.***
*** ******If results follow detailed simula-tions, full implementation by 2011.***

*** ******Simulations ************ long. + trans. stochastic cooling + 56 MHz SRF for both beam goes ~2/3 way (with present bunch intensity) to RHIC-II projected ******L****** at order of magnitude less cost, ~5 years quicker than e-cooling.***

## Other Accelerator Improvements: Electron Beam Ion Source

***Other Accelerator Improvements: Electron Beam Ion Source***

**EBIS preinjector replaces tandems for heavy ions ******** lower-cost, more reliable operation**
**Can produce any ions, including noble gases, Uranium, pol’d ****3****He**
**Construction under way, should be completed in 2010**
**Expect future improvements to lead to higher intensities**

## Other Accelerator Improvements Considered

*** ******Stochastic cooling not effective for lower energy HI (too slow) or pp (intra-beam scat. not important)***
*** ******Consider e-cooling with low-E electron accel. (for critical point scan) or Energy-Recovery Linac (for further high-E improvement & eRHIC)***
*** ******Electron lens:  e(~5 keV)-p collisions counteract pp beam-beam tune spread ***

## Detector Upgrades in Progress

## Additional Detector Upgrades:  Improved Vertex Tracking and Forward Acceptance

**Nose Cone **
**EM Calorimeter**
** ****~ 2012**

**VTX**
**Si Barrel**
**2010**

**FVTX**
**Si Endcaps**
**~ 2011**

**Heavy Flavor Tracker -- prototype ~ 2011, install ~ 2013**

**Forward GEM Tracker ~ 2012 **

*** ******PHENIX, STAR vertex upgrades provide resolution to reconstruct slightly displaced vertices associated with heavy flavor hadron decays ************ study heavy-quark flow & equilibration in “perfect liquid”.***

*** ******Improved forward calorimetry enhances ************ - jet acceptance to study light quark E loss and gluon contribution to proton spin***
*** ******Improved forward tracking (STAR) enhances W sign determination to study antiquark polarization in proton.***

## Detector & Luminosity Upgrades  New Physics Milestones

***Measure hadron suppression and flow for identified heavy-quark mesons, possibly baryons (************c****** )***

**STAR projections for D****0 ****central-to-peripheral    yield ratio**

**STAR projections for D****0 ****elliptic flow**

## Detector & Luminosity Upgrades  New Physics Milestones

## Strawman 5-Year Run Plan (With Decent Budgets)

| 
Fiscal Year | Colliding Beam Species/Energy | Comments |
| --- | --- | --- |
| 2008 | 200 GeV d+Au | Ongoing |
|  | 200 GeV p+p | Assumes sufficient FY08 funding for p+p run |
| 2009 | 200 and 500 GeV p+p | Complete longitudinal asymmetry measurements at 200 GeV and develop 500 GeV performance |
|  | 200 GeV Au+Au | Permits test of 1st plane of transverse stochastic cooling + additional J/ v2 statistics + ... |
| 2010 | 500 GeV p+p | 1st substantial 500 GeV run allows clear observation of W production signal |
|  | Au+Au at assorted low E | STAR TOF upgrade fully installed; 1st part of energy scan to search for QCD critical point – focus on higher among scan energies, where luminosity sufficient |
| 2011 | 200 GeV Au+Au | Full implementation of stochastic cooling in place, PHENIX VTX upgrade complete  long run to reap benefit for rare probes |
|  | 200 GeV U+U ? | Utilize EBIS for first measurements with highly deformed nuclei, to increase energy density coverage |
| 2012 | 500 GeV p+p | Long run in anticipation of 2013 DOE performance milestone on W production, sea antiquark polarization |
|  | Au+Au at assorted low E | Complete energy scan with improved luminosity at very low E from low-energy e-cooling implementation |

**Physics priorities will determine machine upgrade priorities.**

## A Path to an Electron-Ion Collider

**eRHIC, ~ $700M including new detector**

** ****Deepen the science case:  ****what is *****transformational***** about EIC?  Why should other scientists, public care about dense gluonic matter?  What does one learn from unique opportunity to measure effects of large gauge boson occupancy?  How does it illuminate other issues?**
** ****Broaden the science case:  ****Is there an achievable and compelling *****electroweak symmetry *****program?  Running of weak coupling below Z****0**** resonance? Novel measurements of parity violation (e.g., via helicity-dependence of stored beam lifetime) feasible?**

** ****Settle on machine design: ****is there one that gets most of the physics at achievable cost? Can BNL and JLab cooperate on it?**
** ****Expand e-A community!**
** ****Need compelling case/ presentation by next NP LRP (2012-13?)**
** ****Construction by 2020 will be challenging!**

***A Path to an Electron-Ion Collider***

**See T. Ullrich talk Friday morning...**

## Conclusions

**Despite year-to-year Congressional budgeting issues, RHIC luminosity and detector upgrades are proceeding well, fueled by technological breakthroughs, e.g., stochastic cooling for bunched beams.**
****** ****Anticipate a vibrant RHIC heavy-ion program over next ~10 years quantifying “perfect liquid” properties with upgraded detectors & added stimulation from LHC HI results, and searching for the QCD critical point.**
**Vigorous, coherent organization of theorists and experimentalists essential to quantify extraction of physics from RHIC/LHC HI results.**
**RHIC Spin program continues in parallel to converge on understanding of partonic origins of nucleon spin.**
**New BNL focus on large-scale computing will help to fuel advances in LQCD characterization of partonic matter at high energy density.**
**eRHIC presents attractive path to next-generation studies of condensed strongly interacting matter and nucleon spin structure, but science case needs strengthening.**

## Backup Slides

## RHIC Spin Would Also Benefit from Luminosity Enhancement

** ****May be needed for decisive parity-violating helicity asymmetries for W**** ******** production in 500 GeV p+p ******** *****u***** vs. *****d***** sea antiquark polarizations, predicted to differ substantially in chiral nucleon structure models.**
** ****Enable decisive transverse spin asymmetries for Drell-Yan dilepton production, to test QCD prediction of sign difference from semi-inclusive deep inelastic lepton scattering ******** test understanding of connection to parton orbital angular momentum in the proton (another possible component of “missing spin”).**

## RHIC Present Healthy Despite FY06-07 Funding Issues: Important New Results I

***RHIC Present Healthy Despite FY06-07 Funding Issues: Important New Results I***

- Non-photonic electrons at high pT mainly from c,b decays

- Light-q jets 

## RHIC Present Healthy Despite FY06-07 Funding Issues: Important New Results II

** ****Agreement at resonances (********)**
** ****Au+Au enhancement for  0.2 < ****m****ee**** < 0.8 GeV**

**PHENIX -- arXiv:0706.3034**

***RHIC Present Healthy Despite FY06-07 Funding Issues: Important New Results II***

**Au+Au dilepton spectrum differs strikingly from p+p (and from simulated “cocktail” of hadron decays) in continuum region below ********-meson mass!  Effect most pronounced in central collisions.  ****Is ********-mass downshifted, as expected when chiral symmetry of QCD is restored at high temperature?**

## Slide 24

## Future PHENIX Subsystems

**Nose Cone Calorimeter**

**Silicon VTX and FVTX**

***Future PHENIX Subsystems***

## Timeline of PHENIX upgrades

***Timeline of PHENIX upgrades***

**2008**

**2012**

**RHIC**

**2010**

**Inner pixel layers**

**Stochastic cooling “RHIC II”**

**2014**

**Outer strip layers**

**Construction**

**VTX**

**Large acceptance tracking |********|<1.2**

**Displaced vertex at mid rapidity**

**FVTX**

**Displaced vertex at forward y **

**Physics**

**NCC**

**AuAu dileptons **

**HBD**

## Expected v2(be) and v2(ce) with VTX

***Expected v******2******(b************e) and v******2******(c************e) with VTX***

**Decisive measurement of v****2**** for both c and b**

- RHIC II increases statistics by factor >10

## Heavy Ion RAA with FVTX (II)

**Statistical separation of charm and bottom with DCA cuts**

## Examples of Quarkonium Spectroscopy at RHIC II

***Examples of Quarkonium Spectroscopy at RHIC II***

**J/******** measurements will **
**reach high precision**

## Quarkonium Spectroscopy with Forward Upgrades

**With NCC/FVTX**

***Quarkonium Spectroscopy with Forward Upgrades***

**Reference model based on consecutive melting without regeneration**
**(Note: This results in small ********’, ********C ****yields,**** ****other models like regeneration model **
**            ****will give similar yields for J/********, ********’, ********C ****!) **

## Upgrades to keep the discoveries rolling ...

- Forward Meson Spectrometer
- Gluon density distributions, saturation effects, and transverse spin
- DAQ1000 Upgrade
- order of magnitude increase in rate (1KHz)
- extra livetime opens the door to rare physics
- Full Barrel MRPC TOF
- extended hadron identification at intermediate pT
- Lepton identification at low momentum
- Heavy Flavor Tracker
- high precision Heavy Flavor Tracker near the vertex
- opens the door to direct topological ID of Charm & Beauty
- Forward GEM Tracker
- end cap tracker for W sign determination
- Muon Telescope (BNL LDRD)
- Forward Reaction Plane Detector
- A Crystal Calorimeter for low E photons
- -  HBT

**Underway**

**R&D/Proposal Stage**

**Concept Dev.**

## Forward GEM Tracker (FGT)

- 6 triple-GEM disks covering 1 <  < 2
- outer radius ~ 40 cm
- inner radius varies with z position
- charge sign reconstruction probability of W above 80% for 30 GeV pT over the full acceptance of the EEMC for the full vertex spread ( > 90% out to η= 1.8)

## STAR Forward Meson Spectrometer (FMS)

- Detectors are stacked on the west platform in two movable halves.  This view is of the south FMS half, as seen through the retracted west poletip.

- Schematic of the FMS as seen from the interaction point.  The small-cell inner calorimeter has 476 detectors and the large cell outer calorimeter has 788 detectors.

## Schedule

- Beam Use Request strongly coupled with detector upgrades to optimize the maximum physics output

## e-RHIC: a Microscope for Gluon-Dominated Matter

**Soft gluons dominate the proton, but cannot proliferate without bound.**
**At high gluon density, gluon recombination should compete with gluon splitting ******** density saturation.**
**Probe at momentum transfer scales where QCD coupling is relatively weak ******** gluon occupation #’s >> 1  ********  condensate, semi-classical field.**

**Unique ****and ****universal**** predicted aspect of matter best observed at moderate Q****2**** (******** transverse spatial resolution) in heavy nuclei.**
**Most precise measure of gluon densities via QCD corr’ns to Deep Inelastic Scattering (DIS) ******** e-A collider of high/variable energy.**
**Is there well-defined universal saturation scale surface Q****s****2****(x, A)? **

## Add Polarization to e-RHIC to Complete Nucleon Spin Structure Map

***Add Polarization to e-RHIC to Complete Nucleon Spin Structure Map***

**Are highly abundant gluons beyond RHIC spin’s kinematic reach even slightly polarized, contributing significantly to overall spin?**
**Greatly expanded kinematic range for polarized DIS at EIC ******** map scaling violations sensitive to soft gluon polarization.**
**With sufficient luminosity, can also carry out deep exclusive photon and meson production with polarized e + N ******** Generalized Parton Distributions sensitive to orbital motion of sea quarks.**