Workshop on Heavy Quark Physics at C-Zero

December 4-6, 1996 - Fermi National Accelerator Laboratory

Establishing a Plan for C0

This workshop has demonstrated that there is interest in assessing whether a modest collider hall can be used for a heavy quark experiment. The roundtable discussion is evidence that there is a willingness to form a coherent group. You, the participants, have made considerable progress on two of the goals of the workshop. Now I need to understand whether you believe that you and the Laboratory can plan and carry out something valuable at C0, given all of the constraints that you must respect. I am listening and looking for signs that a coherent group is in the process of forming. Throughout these closing remarks when I refer to participants I mean a coherent group of participants.

For almost all of you the question is how can I do a good experiment at C0. For some of you the question is reduced to how can a very good charm experiment be done at C0. For many of you, the question is reduced to how does C0 help move the Laboratory towards a B experiment that can address the issues of CP violation that won't be addressed by e+e- B factories, HERA B, CDF and D0 in the next five to seven years. For some of you the question is why should the Laboratory spend $5 million dollars to build a small collider hall when the money could be better spent upgrading CDF or D0 beyond the baseline design or even to upgrade these detectors to the baseline design more rapidly. It is not surprising that this question was raised by CDF and D0 participants during the workshop. While the motive of the questioners is a bit partisan, the question is valid. These are very different questions because the interests are so diverse.

Over the next six months those of you who wish to form a coherent group have to assess whether a high quality experiment can be done at C0 in the time frame of Run II. Run II will almost certainly extend into the year 2003. This workshop has focused on the possibilities for charm physics and/or b physics in a modest collision hall at C0. The experiment need not be the eighth or tenth experiment claiming to be the best search for CP violation in the B system (eight includes Cleo III, Babar, Belle, HERAB, LHCB, CDF and D0 and ten includes that eight plus Atlas and CMS), but it should be a very competitive experiment. Of these eight experiments five are limited to central geometry. I include Babar and Belle in the category of central geometry experiments because the B boosts are less than two.

This workshop is continuing the exploration of the relative merits of a forward geometry. This work goes back a very long time, all the way back to BCD. I note that the only geometries that the Laboratory will consider for C0 are forward geometries because there are already two central detectors at Fermilab. The value of forward geometry will have to be demonstrated and contrasted with the potential of CDF and D0 to do the same physics. It has been stated many times that the forward geometry will provide better efficiency because the accuracy of determining secondary vertices is better. This has to be demonstrated in a convincing way to the Laboratory and my Physics Advisory Committee.

If charm physics is the primary goal, a C0 experiment must clearly advance charm physics beyond the experiments that will be running during the period 2001­2005. If b physics is the primary goal, a C0 experiment must be clearly competitive with experiments that will be running during the period 2001­2005. Moreover, it should have some unique features that are of great interest if it is not superior in the areas where it overlaps the other b physics experiments that will be operational in that period.

Any successful proposal must contain an important component of detector development as one of its secondary goals. Moreover the detector development needs to be relevant to the Fermilab Collider program. I put such a strong emphasis on R&D because I believe that pixel detectors will replace the inner trackers of CDF and D0 sometime during Run II. We must begin on pixel R&D in the next year in order to have the results available to the entire laboratory community, including present collider collaborations. In addition to R&D on pixel development, I envision the need for R&D on fast level 1 vertex triggers appropriate for charm and beauty, high speed DAQ systems and even filters and processors that can reduce the torrent of data that will impinge on a heavy quark experiment. There will be a need for R&D on particle ID techniques suitable for forward collider detectors. Much of this R&D will be essential for all future collider experiments at Fermilab. The R&D should also focus on making these detectors smaller. While the goals of the coherent group will be judged on the value of the physics goals of the experiment, consideration will also be given to the R&D plan put forward by the coherent group.

The Laboratory's Plans for C0 During the Next Six Months

At this moment the Laboratory is planning to build a modest collision hall at C0 in FY1998. There are a number of barriers that could block our plans. First the OMB and DOE could decide that it is not a good idea and as a result the funds for construction of a modest enclosure at C0 will not be identified in the 1998 Congressional Budget Request. If that happens we will have to stop. We will know by early February whether C0 is identified in the FY 1998 Congressional Budget Request. If it appears in the Congressional Budget Request it has to survive Congressional scrutiny and survive the appropriations process. Unfortunately it will be an inviting target.

The Laboratory will begin an intense beam design effort to define a low beta insertion that can work with wire targets and a low beta insertion for colliding beams. These insertions may use the same magnets and they may not. I hope that an insertion can be made from magnets which will exist by mid 1999 or mid 2000. Some of these magnets may be prototypes for our work on LHC low beta insertions. The Laboratory's focus will be on defining configurations for these insertions, so that the dimensions and requirements of the experimental equipment during the period 2000­2002 can influence the specific design of the C0 Collider hall. I anticipate the facilities in the C0 hall would evolve from a primitive fixed target set up to a compact, high luminosity low beta insertion. All of this the Laboratory can do with its resources.

We will be doing this with the expectation that a coherent group will form and that it will propose a combined physics and detector development program of the type outlined earlier.

I have a second reason for building a modest detector hall at C0. Ten years of collider history shows that there will be an experimental effort at C0 during Run II. It happened in 1987, in 1988­89, and again in 1992­96. These efforts were less productive than they could have been because the apparatus had to conform to the space limitations imposed by the Main Ring abort and other equipment at C0. The acceptance of the detectors was so badly disfigured by this equipment that the analysis of the data was unnecessarily difficult. Because the facilities at C0 were so poor it was necessary to provide a significant amount of dedicated collider time for debugging the experiment. In retrospect, these experiments were not cost effective, particularly if the cost of physicists salaries and the cost of dedicated operating time are included. I believe that those costs far exceed the estimated cost of the proposed C0 hall. You might ask why we didn't propose C0 earlier; the answer is we had to wait until the Main Ring could be removed from the Tevatron enclosure, since most of the space limitations are created by the Main Ring. That will be possible when the fixed target run ends in late 1997. One immediate consequence of a reasonable collider hall is that the experiments proposed to use it will be expected to be competitive in today's environment of tight resources. Only the strongest, goal-oriented efforts can succeed; better not to be so limited by the existing hall.

During the next six months the Laboratory will ask the coherent group of participants to produce simulations (paper studies) that can convince the PAC that a high quality physics program can be done at C0 during the period 2001­2005. In addition, the Laboratory will ask the coherent group to develop a plan for bench top detector R&D for FY1997, FY1998 and FY1999. The Laboratory will provide some very limited funding for R&D during 1997 and more funds will be available for R&D in FY1998 and FY1999.

If the coherent group can develop a letter of intent that meets the requirements for a C0 program outlined by the PAC in its recent recommendations to me and then convince the PAC and me that the proposed C0 program is affordable and doable, then the coherent group will be asked to submit a technical proposal. If this can't be done we will stop there, because we will have learned that Fermilab isn't the place to mount a competitive program of heavy quark physics beyond what can be done by CDF and D0 with their baseline detectors. While this will be a disappointment it will allow Fermilab and its users to focus on competitive experiments that address other issues.

If this technical proposal is successful I suspect that 1999 would be the year of transition from a pure R&D program to the construction of a detector at C0. There could be some funding for a C0 experiment in FY1999 provided we can complete the baseline upgrades of CDF and D0 and make a good start on NUMI/MINOS/COSMOS. By the year 2000 there could be a full level of funding. R&D would still need to continue into the year 2000 because this will be the first opportunity to test the large-scale prototype detector components related to fast vertex funding at C0. The detector would be built over the period 2000­2002. Since there has been a tradition in the fixed target program that physics begins with a partially built detectors, physics could start as early as 2001.

Looking over the charge I realized that the phrase "the ability to commission a major collider detector for one of the two big collider regions in 2005" is unrealistic. This is a consequence of the date for the LHC turn on. I suspect that it will not be possible to start to build a Run III detector until 2003 or later. Since the LHC schedule for LHC-B is likely to slip a bit these dates are not too late.

What is next for C0

In closing let me outline in detail what I hope will happen. First let me tell you what Fermilab will do. Fermilab's plans for the next year are contingent on the C0 collision hall emerging from the Congressional Budget request intact. I have noted before that this will be known in February . If that happens:

• Fermilab will continue the design effort of the collision hall and proceed as far with the conventional construction design as the rules will allow.
  
• A concentrated effort on beam systems design will begin with goal of designing a low b insertion for wires and a low b insertion for colliding beams with the separator (actually combiners).
  
• Any related facilities work will be defined.
  
• The simulations effort in the Computing Division will continue with the goal of providing the coherent group of C0 participants with the computing tools for simulations. In order for the level of effort to increase the non-Fermilab members of the coherent group must actively contribute to the work. A detailed simulation of the capability of a C0 detector will be required for a successful letter of intent, LOI. The LOI must conclusively demonstrate the advantages of a forward detector at C0 compared to the central geometries of CDF and D0. This will have to include a very thorough comparison of the tracking capabilities of the three detectors. In the past my PAC has insisted on this. I expect to receive that advice in the future and I will follow it. This is why there is so much emphasis on simulation.
  
• There will be a critical discussion of the C0 workshop by the Fermilab PAC at its January 17­19 meeting. It is my hope, the hope of the Laboratory, that a coherent group will identify itself and make a presentation of their plan to follow up the to-do list generated by the Workshop.
  
• The Laboratory, with the coherent C0 group, will develop an R&D plan. The plan will have to be submitted to Program Planning for consideration. The PAC will review this submission and provide me advice on the appropriateness of the R&D plan. A realistic date for submission and careful consideration of the plan by the PAC would be the April meeting of the PAC.

What do I expect and want the C0 workshop participants and their colleagues to do next?

• First I expect that a coherent group will identify itself. The group will be coherent if it can define the scientific program at C0 during the period 2001­2005 and an R&D program during the period 1997­2001, both of which meet the requirements established by the PAC.
  
• Second I expect that the coherent group will match the scientific effort of the Laboratory scientific staff in this matter.

If all of the preceding tests are successfully passed I will ask the coherent group to submit a letter of intent for the utilization of the C0 hall during the period 1999­2005 by mid May of 1997. If received, the letter of intent would be reviewed by the PAC at its June meeting with the expectation of defining further steps in the process. I expect that the PAC will have unanswered questions after receiving the Letter of Intent and these would need to be answered by the fall 1997 PAC meeting. Once the questions are answered I will ask for a technical proposal. As long as the physics prospects for C0 are promising I will continue the R&D effort with the expectation that this will be a successful technical proposal.

Return to CZero Workshop