Fixed Target Program - Internal Target
- Main Ring group preparing for first NAL experiment (February, 1972)
- First 200 BeV tracks in 30-inch bubble chamber! (June, 1972)
- Neutrino Laboratory Physicists
- Internal Target Section experiments in full swing (July, 1972)
- Internal Target head reports progress (June, 1973)
Bending and quadrupole magnets were wired into series during the first part of the week to improve tracking. Acceleration to energies three times greater than transition was achieved. Attempts to accelerate to higher energies are continuing.
MAIN RING GROUP PREPARING FOR FIRST NAL EXPERIMENT
The excitement of the final stages of bringing the NAL accelerator into operation was almost equaled by the suspense of waiting to start the first experiment on the machine. And NAL had a group of men working on both fascinating aspects of high energy physics at the same time.
The group included Ernie Malamud, Ryuji Yamada, Dick Carrigan, Bruce Strauss, Jim Klen, and a group of NAL technicians. They were part of a larger group preparing Experiment Number 36, titled, "Small Angle Proton-Proton Scattering," which included men from three other institutions - Rockefeller University, New York City; the University of Rochester, Rochester, N. Y.; and the Joint Institute for Nuclear Research in Dubna. Experiment 36 was the first to be performed at NAL.
The first phase of the experiment employed a tiny rotating "target" of polyethylene film .0001 inches thick. The target was installed just under the beam pipe in the tunnel below Service Building C-0. It was lifted into the beam line by an electric motor when beam became available to the experimenters.
A vacuum can slantsed up at an angle from the target installation to several small counters in the C-0 building corridor. The slant angle was chosen so that the maintenance crew's golf carts could pass freely under the vacuum chamber without the riders having to duck their heads. The results that occurred when the target was struck by the Main Ring proton beam were gathered on a computer in the building above and then measured, studied, and evaluated.
Proton-proton scattering was considered a "simple" experiment. The process is somewhat analogous to a "billiard ball collision." The original proton strikes the target and scatters in a manner quite similar to a grazing collision of two billiard balls. One proton recoils almost perpendicular to the beam line just as the target billiard ball does. The characteristics of the proton (the ball) become clearer; the angles and distribution of the recoils give clues to the shape of the proton. One of the prime advantages of using the Main Ring was that the experiment could be carried out as the machine accelerated and data taken at all energies during a single machine pulse.
 (L to R) Physicists E. Malamud and R. Yamada are involved both in Main Ring operations and in Experiment 36 |
 (L to R) Tony Rader, Richard Applegate and Jack Johnson preparing the nitrogen shield for the long liquid helium transfer line |
 Jim Klen checking status of vacuum system |
 (L to R) Bruce Strauss, Jim Klen & Ed Podscheweit testing flexible helium transfer line |
 Steve Olson at the PDP 11 computer which will gather data for Experiment 36 |
Photos by Tim Fielding, NAL
Physicists Malamud and Yamada were assigned to the NAL Accelerator Section. Both were deeply involved for many months in the design, construction and commissioning of the accelerator. Their work in the Main Ring led to their interest in the possibility of utilizing it directly for experiments. Their expertise brought to the experimental group the distinct advantage of knowing the temperament of the giant machine, for they both spent many hours at the Main Ring control console in the course of bringing the machine into operation.
Strauss, a metallurgist, was also a cryogenic specialist and familiar with engineering problems in the Main Ring. Jim Klen and the technicians brought installation know-how to the effort, having lived with the vacuum system of the Main Ring since construction began.
When the NAL group changed hats and moved from construction headquarters to the Experiment 36 location, they went to Service Building C-0 on the Main Ring Road. There they joined Steve Olson, a physicist from Rockefeller who had been on site since June of 1971, working on construction of the experimental equipment, I Hung Chiang, physicist, and Dan Gross, graduate student, both from Rochester. Chiang and Gross planned and built the electronic equipment that was part of the experimental apparatus.
The second phase of Experiment 36 substituted a hydrogen gas jet for the foil target. Equipment for this phase was installed in the beam line just ahead of the foil target. The results obtained when the proton beam struck the gas jet was studied by the group. But this activity involved much more complicated equipment. 'To keep the gas from seeping into the Main Ring vacuum chambers after it performed its function as a target, it was frozen by allowing it to strike a helium-coated plate at the base of the apparatus. The frozen gas became a solid "chunk of ice" which at intervals was raised out of the apparatus and recycled. The second phase of Experiment 36 was carried out with the Dubna collaborators who pioneered this technique.
Thus, the NAL Main Ring was the stage on which a major physics drama was played. The exhilaration of watching the new machine operate and the satisfaction of providing for the first experiment on it provided the plot and the action.
Source: The Village Crier Vol. 4 No. 6, February 10, 1972
The accelerator operated satisfactorily on June 8 providing 200 BeV beam to the Neutrino Laboratory. After an initial test run of over 5,000 pictures taken with 35mm cameras, an additional 37,574 pictures were taken with the 70mm stereo camera system on the 30-inch Buble Chamber during the running period of June 25th.During a 3-day shutdown beginning June 26, computer improvements in the control systems were instituted. A search was made of the Main Ring vacuum chamber for obstacles that might account for beam loss. The hydrogen gas target for Experiment 36 was installed in the Main Ring.
FIRST 200 BeV TRACKS IN 30-INCH BUBBLE CHAMBER!
Bubble Chamber at NAL June 15, 1972. A 200 BeV
proton enters the Chamber and interacts with the
liquid hydrogen; resulting collision produces a
spectacular event with ten visible nuclear
fragments emerging; tracks were nearly 30 inches long
The fifth anniversary of the National Accelerator Laboratory on June 15, 1972, was highlighted by the display of the first photos of 200 BeV tracks in the 30-inch Bubble Chamber. Announcement of the successful run of the beam, which occurred about 5:45 a.m. on June 15, was made by NAL Director Robert R. Wilson at a meeting for the 950 employees of the Laboratory. "It means that we're in business," he told the group. "The whole Laboratory is now being exercised."
Ernest Malamud. head of NAL's Internal Target Section, announced that one million elastic scattering events had already been observed at the internal target positioned in the Main Ring vacuum chamber at Building C-0 as part of Experiment No. 36. "We are doing very significant experimenting now," Dr. Wilson commented. "This is becoming a physics laboratory and we can talk about the discoveries that will be made here."
Dr. Wilson also outlined the immediate goals in the continuing NAL development program, such as increasing beam intensity by a factor of 1,000 and bringing all experimental areas into operation. "Our success from here on will be measured by our efforts in these directions," he said.
The Bubble Chamber success came after a week of sustained efforts that began June 8, 1972 when the first 200 BeV beam was handed off to the Neutrino Laboratory from the Switchyard. (On May 29, 72 BeV particles went through the Neutrino Line in an initial test.)
With the main accelerator operation consistently reliable at 200 BeV, the tuning of the Neutrino line at the higher energy became the highest priority assignment at NAL. For the Neutrino Laboratory staff, day and night hours became one thing. Deeply engrossed in the intense efforts, many found it difficult to break off even for sleep; twenty-two hour shifts were not uncommon among the physicists. One reported finding a fellow physicist parked along Butterfield Road after one of these long stints, who commented simply, "My car ran out of gas and so did I."
NAL employees gathered outside the Curia on Thursday, June 15, 1972 for Directors meeting
The NAL Neutrino Line is 1.5 miles long. Adjustments will be necessary, at all of the ten buildings on the Line. Systematic, patient analysis of progress and problems was the key to success. The sport of the job was reflected in the simple jubilation of the entry in the log book at 0545 on June 15, 1972: "Got him!"
By Monday, June 19, after a period of several days of "cleaning up" the tracks, staff members were able to record in the log: "Looks Good," as they accumulated the first complete roll of film of photographs of the 200 BeV beam passing through the liquid hydrogen in the Bubble Chamber.
As described in the December 2, 1971 issue of The Village Crier, the Chamber was moved to NAL from Argonne during 1971. Studies of the interactions of particles that were recorded on the first test pictures began. Researchers from approximately thirty laboratories were involved in the ten approved experiments which were planned for this area. The first of these, Experiment Number 141, got underway with pictures of 200 BeV proton - proton collisions being measured on a round-the-clock basis at the Argonne National Laboratory as the experiment at NAL.
According to Louis Voyvodic, physicist in charge of the 30" Chamber and a participant in the first experiment, "The tracks and interactions seen in the chamber on the morning of June 15 were a beautiful sight, both scientifically exciting and aesthetically striking.
It was also satisfying to watch the enthusiasm and feeling of fulfillment, after years of effort, as physicists, engineers and technicians from the accelerator, from the beam lines and from the Bubble Chamber areas took turns viewing the tracks flashing away in the Chamber."
NEUTRINO LABORATORY PHYSICISTS
 W. Fowler |
 R. Huson |
 J. Lach |
 F. Nezrick |
 S. Pruss |
 W. Smart |
 R. Stefanski |
 T. Toohig |
 L. Voyvodic |
 R. Walker |
 T. Yamanouchi |
Source: The Village Crier Vol. 4 No. 24, June 29, 1972
PROGRESS REPORT - JUNE 26 THROUGH JULY 8, 1972
The Accelerator operated principally at 100 BeV since the June shutdown, for the tuning of the muon line. The first muons were detected in the Michigan State-Cornell experiment on July 2nd at 3:05 p.m. Promising tests were conducted on rapid cycling of the Booster.
INTERNAL TARGET SECTION EXPERIMENTS IN FULL SWING
 Jet Target assembly in NAL Main Ring, a collaboration of Soviet and American physicists |
 V. Nikitin of U.S.S.R., E. Malamud, B. Strauss of NAL In Main Ring tunnel at C-0 |
On April 12, 1971, the "Internal Target Section" was added to the NAL working structure. With headquarters at 35 Shabbona in the NAL Village, the group was organized to assist and expedite the installation and operation of experiments that utilize the Main Ring vacuum chamber in a straight section located at position CZero (C0) on the Ring. Ten weeks later, three experiments were installed and regularly collecting data.
Headed by physicist Ernest Malamud, who was associated with the NAL Main Ring construction and operation since January of 1968, the Internal Target Section's first assignment was to aid Experiment No. 36, a collaboration of NAL, Rockefeller University, the University of Rochester, and the U.S.S.R. (See the February 10, 1972 issue of The Village Crier.) In February of 1972, the first phase of the experiment was installed utilizing a tiny rotating target of polyethylene foil built at the University of Rochester. Beginning on March 6th, data was recorded as the proton beam struck this target. The number of protons bouncing off the target at different angles revealed the extent and characteristics of the forces between the protons. The experiment revealed how the radius of the proton varies with the energy of the beam.
An exciting new phase of Experiment 36 began when installation of a hydrogen gas target was completed. The assembly and installation followed more than a year of weekly communications by teletype between NAL and scientists from the Soviet Union who had originated the technique of using a narrow band of tiny hydrogen ice crystals as a target for the proton beam. In regular Thursday morning teletype talks, the Soviets and NAL staff members made plans for the collaboration which provided that the jet would be built in the Dubna machine shop, brought to NAL, and joined with a vacuum box, alpha particle calibration source, rotating foil target built in the United States.
 Members of Exper. 67 crew (L to R) Felix Sannes, Michael Lieberman, Jim Mueller, George Cvijanovich |
 Ion guide built by NAL Machine Shop staff: (L to R) Jim Forrester, Walt Limbough, Jim Schmidt, Roger Hitler, Tom Butler |
 Installing apparatus for Exper. 220, John Whittaker |
 Soviet experimenters (L to R) y. Pilipenko, A. Kuznetsov, and V. Bartenev |
The Soviet group of seven scientists and their wives arrived for a one-year visit in the U.S. on March 5th, 1972. They brought the completed jet target, controls, electronics and detectors with them. They arrived in time to join the NAL staff on March 8th celebrating the reaching of 200 BeV design energy. The succeeding weeks saw the gradual fulfillment of the cooperative venture as Russian and American equipment was connected together.
Members of the Russian group were - Victor Bartenev, Anatole Kuznetsov, Boris Morozov, Vladimir Nikitin, Yuri Pilipenko, Vladimir Popov, and Leonid Zolin.
By May 20th, the assembly and testing of the target began to yield successful results. Test runs on May 25th and June 10th were also satisfactory. In a massive 4-day effort beginning June 26th, the target was moved from the Village and installed in its final position in the Main Ring tunnel. By June 28th, the helium transfer line, approximately 100 feet long, running from the liquifier on the ground level down to the tunnel was also completed. Liquid helium started filling the dewar in the tunnel on the evening of June 29th.
Experiment 36 started operation of its second phase immediately. The group had already logged 318 hours of "target in" time with their foil target. About 12 million events were collected at 80 BeV and 23 million at 200 BeV.
Experiment No. 120 also shared the target measuring gamma rays. The experiment involved scientists from Harvard University and the University of Wisconsin.
Another group -Experiment No. 67 - which includes physicists from Rutgers University, Upsala College, and Mississippi State University, studied the protons recoiling off this target to learn about resonance structure of the proton.
NAL staff members of the Internal Target Section included: Jim Klen, Ernest Malamud, Joel Misek, Don Mizicko, Chuck Nila, Wally Pelczarski, Barb Perington, Ed Podschweit, Tom Rathbun, Buzz Rodewalt, Bruce Strauss, Dave Sutter, Ryuji Yamada. Bill Carter ran the staff shop used by the Internal Target and Proton Lab Sections. Jim Batek, Sharon Fleming and Verence Moore joined the section for the summer months.
Source: The Village Crier Vol. 4 No. 25, July 13, 1972
INTERNAL TARGET HEAD REPORTS PROGRESS
Experimentalists working in NAL's Internal Target Area completed taking data for four experiments, including the highly-successful U.S.-U.S.S.R. collaboration which opened its research in January of 1972 as the NAL machine first reached an energy of 100 BeV. According to Drasko Jovanovic, head of the Internal Target Group, completion of these experiments deserved special notice because they provided very early experimentation in an experimental area in the Main Accelerator before the external experimental areas were completed.
"At one point in NAL planning, such an area was thought to be potentially detrimental to the operation of the machine, primarily because of the possibility of excessive radioactivity," Jovanovic observed recently. "But we proved that the internal target was not only feasible but rather valuable. Experimenters were able to utilize the wide range of energies in the Main Accelerator and to benefit from study of the increases in energy before extraction. No small credit should be given to our Soviet collaborators who first applied the gas jet technique at Serpukhov in 1968."
Jovanovic's appointment as head of the Internal Target Group in NAL's Accelerator Division, came at a point when the Group was considering its next direction, having finished Phase I of its program. He brought in the knowledge he had gained since he became attached to the Accelerator Division development in mid-1972. For some months before that, while working for the Argonne National Laboratory, he lent his hand where needed at NAL. Tall, smiling, and energetic, Jovanovic was born in Belgrade, Yugoslavia, where his father headed the physics department at the University of Belgrade, and his mother was also in physics. The elder Jovanovic was an assistant to Marie Curie in Paris for 12 years. Drasko came to the University of Chicago on a UNESCO fellowship; he received his Ph.D. from Chicago. After crossing the U.S. thirty times between 1960 and 1962 as an experimenter at the Brookhaven National Laboratory in New York where he and his wife and family maintained residence, and at the same time serving as a faculty member at LaJolla Branch of the University of California, Drasko received a domestic ultimatum from Stanka. The solution - live near an accelerator.
Dr. Jovanovic's long acquaintance with accelerator laboratories gave him much expertise in the problems of radioactivity. Putting this to work immediately in the Accelerator Division, he designed "the Rover," a golf cart outfitted with detection equipment. A projecting wand on the Rover recorded data on radiation levels, enabling one person to monitor the 4-mile Main Ring quickly and efficiently.
Source: The Village Crier Vol. 5 No. 23, June 13, 1973
"PIONEER" EXPERIMENTS WIND DOWN
 Celebrating Internal Target successes are (L-R): P. McIntyre, R. Huson, S. Olsen, R. Rusack |
 Internal Target area (arrow) on Main Ring at CZero Service Building |
 Soviet-American scientists at CZero (1977) Front Row (L-R)--V.Nikitin, R.Yamada, B. Morozov; Standing (L-R)--D.Gross, P. Nomokonov, Y. Pilipenko, E.Malamud, A. Kuznetsov, V. Smirnov |
The Internal Target Group recently reached a milestone in its experimental program. Three groups have completed experiments there during the past months, in each case bringing to a successful conclusion a series of experiments running more or less continuously since the early days of Fermilab high energy physics.
In November 1977 the Soviet-American collaboration completed Experiment 289, a study of small angle p-He scattering. This collaboration, working at CZero since 1972, first developed a cryogenic H2 jet for use in internal target experiments. Its members include Edgar Jenkins, Ernie Malamud, Mitsuhiro Miyajima, Ryuji Yamada, Anatole Kuznetsov, Vladimir Nikitin, Yuri Pilipenko, Andrezej Sandacz, Boris Morozov, Peter Nomokonov, Vitali Smirnov, Adam Bujak, and Dan Gross. This jet, designed by Yuri Pilipenko and Victor Bartenev, produces high jet density while maintaining good Main Ring vacuum.
Experiment 522 by the Indiana University group, studied inclusive polarization in p-p scattering. Its members include Steve Gray, Bryan Martin, Homer Neal, Harry Ogren, Robert Polvado and Dave Rust. They first began working at CZero in 1974 on Experiment 313.
Experiment 552 by the Rutgers/ Rochester/ Imperial College group, measured differential cross-sections for pp and pd elastic scattering. Its members include Steve Olsen, Gary Warren, Renee Warren, Felix Sannes, Bruce Collick, Roger Rusack and Ion Siotis. They were the first group to use the superconducting spectrometer at CZero (Experiment 198). This spectrometer, designed by Steve Gray, Paul Mantsch, Joel Misek and Chuck Nila, is a large remote-controlled movable superconducting quad/dipole system.
The past year has been an extremely busy one for the Internal Target Group, headed by Peter McIntyre. In addition to supporting the experimental program described above, the group has designed and is constructing the electron beam for the proton/antiproton cooling ring.
Joel Misek, Chuck Nila, and Larry Sobocki have designed all electron beam components. Bill Kells and Denny Curl are building microwave and laser diagnostics for the beam. Ed Faught is working with the Controls Group (Bob Ducar) to build the control system which interfaces the electron beam components to computer control.
Lloyd Klein, Paul Kurylo, and Tom Rathbun are installing the special aluminum-foil solenoids, built at CZero, which contain and guide the electron beam. Roy Meeks and Bill Weihmiller are assembling the large toroid magnets that bend the electrons in line with the proton beam. Ed Podschweit and Larry Sobocki are building a large high-vacuum, high-temperature bakeout oven; all vacuum components for the ring will be baked to 8000 C to achieve <10-10 Torr vacuum in operation.
Don Mizicko has performed the Herculean task of choreographing all the above activity in parallel with an around-the-clock operations schedule. Les Oleksiuk has developed computer calculations of the magnetic field that confine the electron beam, and of electron trajectories in the beam.
No further experimental operation is planned until early 1979. In the coming months, the Internal Target Group will play a strong role in completing the cooling ring. They are also supporting the program headed by Stan Pruss to improve the Main Ring vacuum so as to extend coasting beam lifetime for colliding beam studies.
Source: The Village Crier Vol. 10 No. 17, April 27, 1978