The following viewgraphs were presented by Brett Parker during the "Accelerator Physics Parallel Session I" of the eRHIC Workshop on eA and polarized ep Collider Physics held April 6-8, 2000 in the Sloane Physics Laboratory at Yale University. The viewgraphs are saved in jpeg format and should be viewable with most browsers and many graphics utilities.

We cite examples from the HERA Luminosity Upgrade at DESY where such detector interface problems for the ZEUS and H1 experiments have been worked out. Other detector interface examples presented here are taken from the PEP-II Asymmetric B-Factory Conceptual Design Report (LBL-PUB-5379) dated June 1993. The HERA-B e-beam compensation scheme, one of the accelerator modifications made for the HERA-B experiment at DESY (described in DESY-PRC 95/01), is presented as an example for just how challenging it can be to send a polarized electron beam though an experimental detector magnet (while maintaining electron polarization).

 "Investigating the Experimental Detector Accelerator Interface: eRHIC" presented by Brett Parker, BNL Superconducting Magnet Division.

 Can you provide some background on what has been done in the past?

 Are you positive that you know all the particles that are involved?

 Ok, so how low in energy do we have to go?

 Do these particles have any special features or unique characteristics?

 Spin rotators, they sound interesting. What are they really like?

 Is there a need for something similar to the HERA LPS and Luminosity Monitor systems?

 What is wrong with generating some synchrotron radiation (synrad)? How critical is it anyway?

 What does it mean to have to let the synrad pass through an experiment?

 How hard can it be to control synchrotron radiation albedo?

 What about the eRHIC straw design optics? What do things look like near an eRHIC IP?

 What can we learn about improving optics from the HERA Luminosity Upgrade? How is the HERA IR layout changed for the upgrade?

 Besides putting superconducting magnets in the H1 and ZEUS experimental detectors, what else is DESY doing for the HERA luminosity upgrade?

 If the 700 m beta-maxima found in the eRHIC straw design seem in the light of HERA upgrade studies to be too large, how can we get these beta-peaks down?

 Are there other experiments at other accelerators which are faced with these same design challenges?

 Please describe the PEP-II B-Factory IR design at SLAC in more detail. How is SLAC able to start early beam separation and keep beta-maxima from getting out of hand?

 What are tapered permanent magnet dipoles and quadrupoles and how do they work?

 So with special magnets inside experimental detectors, what do the High Energy Ring (HER) PEP-II B-Factory lattice functions look like?

 Other than putting magnets inside experiments, what can be done to reduce beta-maxima?

 Which way does the eRHIC beam go? What might the beam separation magnets look like?

What more should we know about the eRHIC linac option? Where does it fit in all this?

 Just one more thing... are you sure you can identify the particles which go around RHIC and yet can stay together in the same ring?

 Sorry, one more question, what path does eRHIC take around the accelerator complex? What did HERA-B have to do to avoid spoiling polarization in HERAe?

 What happens to experimental detector backgrounds at HERA when satellite filling causes the effective bunch spacing to be too small? If every eRHIC rf-bucket is filled, isn't there a limit, based solely on detector size, on the usable eRHIC bunch spacing due to this geometric effect? 

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