107422776
The coming revolution in particle physics: Report of the Fermilab Long Range Planning Committee
In early 2003, the Fermilab Director formed a committee (Appendix A) to examine options for the long-range future of Fermilab. Specifically, the committee was asked to respond to a charge (Appendix B), which laid out the assumptions, which were to underlie our discussions. The committee met a few times during the spring of 2003 and formulated a plan of action. It identified a number of issues that deserved attention, and a subcommittee was formed to focus on each. We agreed that in addressing these key issues, a broader participation was appropriate. The manner in which that was achieved varied from subcommittee to subcommittee to group. In some cases the expanded membership participated in all the discussions, in others, particular presentations were solicited and heard. Some subgroups met regularly over several months, others convened only for a small number of discussions. We have attempted to list participants in Appendix C. General presentations indicating the purpose of the work were given, for example at the Fermilab Users Annual Meeting. Towards the end of the summer some sense of direction developed and a series of open meetings was organized by the different subgroups. These meetings of two and more hour's duration gave the broader laboratory and user community a further chance to react to perceived directions and to make their opinions known. They were extremely well attended. In all, nearly 100 people have participated in the process including the development of initial drafts and proto-recommendations. A larger number attended the various open sessions. It is therefore likely, even expected, that the general thrusts of this report are no surprise. Nevertheless, the committee met in a number of plenary closed sessions including a two-day retreat in which all the issues were discussed and a common view was developed. The Director and Deputy Director heard and interacted with the discussions in most of these meetings. In attempting to converge, we have written the individual chapters from a slightly advocative point of view. In the final discussions and editing, we have attempted some damping. Nevertheless, if all recommendations were accepted, all positive options pursued, any reasonable budget would be exceeded. We have balanced this bottom up approach with a top down development. We tried to extract the essence and to provide a couple of balanced options based on the discussions at the retreat. Healthy, lively, and vigorous exchanges ensued which resulted in multiple rewrites and culminated in the Executive Summary for this document. It is there that you should find the most concise product of this process. In preparing the report, we did consider the potential availability of resources. We have devoted a chapter of the report to discuss the limitations of our efforts. It should be recognized that there are large variances among the public opinions about costs of large elements of the program such as the Linear Collider, or even the Proton Driver. The evolution of the laboratory budget is also very uncertain and depends on many things such as the success in physics terms of the current program. We have therefore taken a relatively optimistic point of view in achieving balance. It is in this sense that the report provides options. At any point in time, the Fermilab Director will need to make choices among the options; we hope that the broad thrusts, which we call out, will be helpful. In the remainder of the report we use chapter 2 to describe the Physics Landscape 2010-2020, which is the basis for what we would like to see happen. In chapter 3 we discuss the Linear Collider, which will be a major component of the laboratory program under any scenario and, if constructed nearby, a dominant one. In chapter 4 we describe a vigorous but evolutionary program to address the key neutrino physics areas, and in chapter 5 we discuss attractive initiatives, which would provide the necessary powerful source of protons and, hence, neutrinos for this program. A strong participation in the machine, the experiment (CMS), and the physics at the Large Hadron Collider is a constant for our deliberations and is discussed in chapter 6. Astroparticlephysics, which was introduced to the Laboratory twenty years ago, continues to develop and its growth is discussed in chapter 7. Accelerator research and development, the underpinning of our science core is addressed in chapter 8, and its sister discipline, detector research and development, is covered in chapter 9. In chapter 10 we examine the interdisciplinary science close to our field, which encircles our laboratory. In chapter 11 we outline some of the resource issues and the extent to which they were addressed before we present the conclusions.
14474933
Charm results on CP violation and mixing
The most recent results on CP violation and mixing in the charm system are reviewed as a guide to the future. While no surprising results are reported so far, charm provides a unique window to physics beyond the Standard Model. The results reported here come from four sources, ALEPH at LEP, E791 and FOCUS/E831 at Fermilab, and CLEO II.V at CESR. Results beyond these sources may be expected as a byproduct of B-motivated experiments.
117556562
Search for phi Mesons Produced at High Transverse Momenta in p - Be Collisions at 300-GeV
117907932
Observation of Structure in the $\Upsilon$ Region
The properties of the dimuon enhancement seen in 400-GeV proton-nucleus collisions have been clarified by a threefold increase in data. We find two peaks whose widths are consistent with our resolution: M/sub 1/ = 9.4 GeV with dsigma/dy vertical-bar /sub y/ = 1.8 x 10/sup -37/ cm/sup 2//nucleon and M/sub 2/ = 10.0 GeV with Bdsigma/dy vertical-bar /sub y/ = 0.7 x 10/sup -37/ cm/sup 2//nucleon. Evidence for the possible existence of a third peak near 10.4 GeV is discussed as are the comparison with the properties of a qq-bar system, where q is a new heavy quark.
108208419
Pixel Detector Test
370054
Development of a high density pixel multichip module at Fermilab
At Fermilab, both pixel detector multichip module and sensor hybridization are being developed for the BTeV experiment. The module is composed of three layers. The lowest layer is formed by the readout integrated circuits (ICs). The backs of the ICs are in thermal contact with the supporting structure, while the tops are flip-chip bump bonded to a pixel sensor. A low mass flex-circuit interconnect is glued on the top of this assembly, and the readout IC pads are wire-bonded to the circuit. The BTeV pixel detector is based on a design relying on this hybrid approach. This method offers maximum flexibility in the development process, choice of fabrication technologies, and the choice of sensor material. This paper presents strategies to handle the required data rate and performance characteristics of the pixel module prototypes.
115883664
Time-of-flight measurement in the DZero Central Fiber Tracker
We continue evaluation of the new electronics developed for the Central Fiber Tracker and Preshower detectors. With the custom TriP chip and MCM II we have measured the position of the hits along the fiber by comparing the time of arrival of the photons at the VLPC with the expected timing relative to the beam. The measured rms resolution at the center of the fibers is 46cm for hits with more than 8 photo-electrons and is dominated by the statistics of photon arrival time. The corresponding resolution near the ends of the fibers (where more photoelectrons are collected) is calculated to be of order 27cm. With a second submission of the TriP chip to add the time-of-flight measuring capability we will effectively double the number of channels in the central fiber tracker. This capability will increase the maximum luminosity at which D0 can do tracking from {approx} 100 {center_dot} 10{sup 30}cm{sup -2}s{sup -1} to {approx} 200 {center_dot} 10{sup 30} cm{sup -2}s{sup -1} (at a bench mark tracking specification). The cost of replacing the electronics is of order $500K and the necessary lead time is 1.5 years.