NOVEMBER 1996 the AMERICAN P Hysicalnews SOCIETY VOLUME 5, NO 10 New Results Supporting Standard Model Highlight 1996 DPF Meeting
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Featuring APSONLINE A supplement to A P S N E W S APS News APSNOVEMBER 1996 THE AMERICAN P HYSICALNews SOCIETY VOLUME 5, NO 10 New Results Supporting Standard Model Highlight 1996 DPF Meeting ew experimental results increase detector groups. The combined data Higgs mass lies within the lower part Eventually it was determined that the Nconfidence in the Standard Model, also resulted in a more precise of the range suggested by the new data and theory could be brought into including the latest mass measurements determination of the mass of the W measurements of the top quark and W better agreement by modifying the frac- for the top quark, W and Z particles, boson, a carrier of the so-called weak particle, it could be observed at the tion of the proton momentum carried as well as electroweak precision mea- force. The new mass, expressed as an upgraded LEP-II collider at CERN. If the by energetic gluons. surements, according to speakers at average from Fermilab’s CDF and D0 mass is towards the higher range, sci- Last year, scientists at the HERA elec- various invited and contributed ses- detectors and from CERN experiments, entists may have to wait for a future tron-proton collider in Germany sions of the 1996 APS Division of was determined to be 80.35 GeV, upgrade of the Tevatron or for CERN’s reported that the density of low mo- Particles and Fields (DPF) Meeting, held reducing the overall uncertainty from Large Hadron Collider, scheduled to mentum gluons in the proton was 10-15 August in Minneapolis, Minne- 160 to 130 MeV/c2. begin collecting data in 2006. much larger than expected. Using new sota. This year’s meeting also featured The mass of the Z boson has been special detectors, the H1 and ZEUS ex- QCD Theory reports on the first observation of W+W- determined as 91.1863 ±.0020 GeV/c2, periments found that this excess pairs and exciting new results in QCD as a result of new extremely precise Fermilab’s Liz Buckley-Geer, who persists down to those gluons carrying theory. measurements that emerged from the spoke on Thursday morning, reported as little as one-millionth of the proton’s ALEPH, DELPHI, L3 and OPAL experi- that the CDF detector also produced momentum, a striking effect that may New Precision Measurements ments at CERN’s LEP electron positron measurements of quark or gluon jets provide evidence of a new regime in More precise measurements of the top collider, as well as the SLD experiment at large angles with respect to the pro- which perturbative treatment is sup- quark have been achieved at Fermilab’s at SLAC. In addition, new measurements ton beams, and with energies planted with collective effects of Tevatron collider merely one year after from the CLEO experiment at Cornell approaching half the energy of incom- multiple-gluon states. In addition, sci- its momentous experimental discovery University helped resolve two possible ing beam particles. While the data entists with CERN’s LEP collaborations was announced. According to Sally areas of deviation observed last year at agreed qualitatively with QCD predic- have succeeded in isolating pure samples Dawson of Brookhaven National Labo- LEP and SLAC in the rate of decay of the tions in the production rate, data for of quarks or gluons emerging from Z ratory, who closed the conference with Z boson into charm and anti-charm the largest-energy jets exceeded pre- boson decay, which had previously been a summary of the year’s highlights in quarks, and in the rate for Z decay into dictions by nearly a factor of two. In experimentally indistinguishable. This particle physics, the new results are bottom and anti-bottom quarks. contrast, the D0 experimental data, ability could become an important ex- viewed by many as a triumph of the In addition to providing further ex- agreed more closely with QCD theory. (Continued on page 3) Standard Model, although some key perimental confirmation for the questions remain unresolved. Standard Model, these improved par- The new mass of the top quark is ticle measurements are an important determined to be 175 ±6 GeV, an link to finding the as-yet-unobserved improvement in precision by a factor Higgs boson, which endows the W and of two. The 100 candidate events used Z bosons with large mass and is also INSIDE THE BELTWAY to calculate a new value for the top believed to be responsible for breaking quark mass represent the combined the symmetry between the weak and Science in Crisis: Fact or Fiction inventories of both the CDF and D0 electromagnetic forces. In fact, if the by Michael S. Lubell, APS Director of Public Affairs ashington is a town that thrives further than the new five-year projec- Won accusations, leaks and exag- tions for the federal science budget. geration. The goals of the propagandists Democrats and Republicans, alike, have are control, power and turf. And captur- repeatedly proclaimed strong support for ing the attention of the media is central basic research. But whether the budget to any success they might achieve. forecasts emanate from the Democratic In an age of electronic communica- White House or the Republican Congress, tion, channel surfing and limited the out year spending plans for science attention spans, the 10-second sound are anything but encouraging. bite has become crucial for anyone The presidential budget, released in hoping to get a message across. For March and adjusted in July, forecasts a science, the message this fall has been drop of 18.1 percent in constant dollars reduced to a single word — Crisis! for the National Science Foundation’s R&D account over the period 1995 to The APS Committee on Committees A little more than a month ago, Presi- dential Science and Technology Advisor 2002. The Republican plan, contained No kidding! Just as many of you suspected, the APS even has a committee to keep track of its Jack Gibbons and other analysts punc- in this year’s congressional Budget Reso- many (about 20) committees. Pictured above are: Joseph Dehmer (standing at left), Martin Blume, tuated this exclamation in commentaries lution, offers a slightly more positive Laura Greene, Amy Halsted (committee administrator), Ernie Henley, James Wynne, Zachary Levine at the George Washington University projection, but still shows a cut of 6.8 (standing) and Anthony Johnson. Barbara Levi, COC chair, is not in the photo. This hard working symposium Science in Crisis at the Mil- percent. group of member volunteers selects about 40 members out of 400 nominees to fill openings on lennium. A day later, similar notes For the Department of Energy, which 1997 APS committees. COC also conducts reviews of committee activities. Now, as to who keeps reverberated in the marble rotunda of accounts for about 50 percent of all fed- track of the Committee on Committees… the Low Memorial Library at Columbia eral funding in the physical sciences, the University, site of the conference Science out year projections are even bleaker. the Endless Frontier, 1945-1995. During the last few years, the DOE has IN THIS ISSUE For scientists, policy makers and been an agency under siege. Attacks politicians, the central question is how on it have come from antagonists at New Results Supporting Standard Model Highlight 1996 DPF Meeting ..... 1 much truth underlies the rhetoric? To both ends of Pennsylvania Avenue. Not Inside the Beltway ...................................................................................... 1 find the answer, one need look no (Continued on page 6) Physicists To Be Honored at November Meetings...................................... 2 Aylesworth Observes Politics in Action on the Hill ..................................... 2 1997 March Meeting: Large & Small, Old & New ....................................... 3 McIlrath to Become New APS Treasurer AIP Offers New Web Site for History of Physics and Astronomy ............... 3 On 11 November, Thomas J. McIlrath the graduate school there. A laser and IN BRIEF.................................................................................................... 3 will become Treasurer of The Ameri- atomic physics experimenter, he is also Opinion ....................................................................................................... 4 can Physical Society. McIlrath, who a staff member at the National Institute Szilard, Schawlow Inducted into Inventor’s Hall of Fame ........................... 6 holds a Ph.D. in physics from Princeton of Standards and Technology in Schrieffer and Garmire Named to Committee on University, is a professor in the Insti- Gaithersburg, Maryland. McIlrath suc- National Medal of Science ....................................................................... 6 tute for Physical Science and ceeds Harry Lustig, who has been APS Announcements... ...................................................................................... 7 Technology at the University of Mary- Treasurer since 1985. A longer article The Back Page ........................................................................................... 8 land at College Park and associate dean about the new treasurer will appear in APS Meeting News ............................................................................. Insert for research and graduate studies in APS News soon. APS News November 1996 Physicists To Be Honored at November Meetings Five physicists will be honored for their acoustics, turbulence control, large eddy in plasma-based accelerator concepts; 1996 Fluid Dynamics Prize work in fluid dynamics and plasma simulation and parallel computing. particularly