VOL. 4, NO. 3 • WINTER 2001

Continued on page 2

Scientists Encouraged by NSTX Results

High Beta with Good Confinement Reported

By Anthony DeMeo

The National Spherical Torus Experiment

The use of neutral-beam injection heating on the

National Spherical Torus Experiment (NSTX),

coupled with good confinement, has allowed the NSTX

National Research Team to produce a plasma toroidal

beta of up to 22.5 percent based on magnetic measurements. “Initial results are extremely encouraging. We

hope to reach 25 percent during the next experimental

campaign, more than one year ahead of schedule,” noted

NSTX Project Director Masa Ono.
PPPL NEWS • Winter 2001 Page 2

The PPPL NEWS is issued by the Princeton Plasma Physics Laboratory, a research facility supported by

the United States Department of Energy and managed by Princeton University. Correspondence and

requests to reprint material should be directed to: Information Services, Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, NJ 08543; telephone 609-243-2750; fax 609-243-2751; e-mail info@pppl.gov .

PPPL NEWS

Information Services Head: Anthony R. DeMeo

Editor/Writer: Patti Wieser

Photographer: Elle Starkman

Layout and Graphics: Gregory J. Czechowicz

and Patti Wieser

Fusion power production is roughly proportional to

the square of the plasma pressure. Toroidal beta is the

ratio of plasma pressure to magnetic field pressure applied in the long direction of the spherical torus. A higher

beta means that greater plasma pressure, thus substantially more fusion power output, is achieved with a given

magnetic field strength. The cost of a fusion reactor will

rise with the strength and size of the magnetic field coils.

Consequently, higher betas in NSTX could lead to the

development of smaller, more economical fusion reactors. The highest toroidal beta value produced by a tokamak stands at about 13 percent.

PPPL physicists, their colleagues from 13 other U.S.

institutions comprising the NSTX team, and collaborators from Japan, Korea, and the United Kingdom, worked

together on the recent experiments. The highest beta was

achieved with only three million watts of neutral-beam

heating power. Five million watts of heating power will

be applied during the next campaign to enable the physics

studies at increased plasma pressures.

Quite surprisingly, the observed energy containment

efficiency of the NSTX plasma improved by as much as

a factor of two as neutral-beam heating was added to the

resistive heating. Furthermore, the NSTX plasma entered

a state known as the “High Confinement Mode”— the

first time for NSTX. Plasmas in the so-called H-Mode

demonstrate substantially improved confinement with a

density that is about as high at the edge of the plasma as

it is at the center. This bodes well for the prospect that

NSTX eventually will have adequate heating power to

test the theoretically predicted toroidal beta values in the

range of 40 percent. In the coming months, the NSTX

National Research Team and the PPPL Theory Department will use results now emerging from NSTX to refine

and expand models for high-beta spherical torus plasmas,

enabling a better understanding of the plasma stability

and confinement properties.

Ono attributes the recent success to the December

1999 achievement of one million amperes of plasma

current, nine months ahead of schedule, which set the

stage for the current experiments. He also noted that

NSTX is building on previous results from machines such

as PPPL’s Tokamak Fusion Test Reactor (TFTR) and the

DIII-D tokamak at General Atomics in San Diego. For

example, the NSTX neutral-beam injection system, which

became operational on September 13 within budget and

ahead of schedule, draws heavily on TFTR design, hardware, and operating experience. The system cost $6

million and took two years to complete.

Using techniques developed on TFTR and other tokamaks, researchers have been able to minimize plasma

impurities in NSTX, especially heavy metals, which

absorb energy from the plasma and release it as ultraviolet

light and X-rays. Such foreign matter enters the plasma

when it interacts with walls of the vacuum vessel. To

minimize this infiltration, large portions of the NSTX

vacuum vessel walls and center column were covered

with protective graphite tiles. Just prior to the neutralbeam experiments, the vacuum vessel and tiles were

heated to 150 ̊C and the center stack to 300 ̊C to drive out

water vapor. A helium glow discharge was used to reduce

the influx of hydrogen bound up in the walls. The reduction of hydrogen helps make plasma operation more

reliable and improves performance. A glow discharge is

a tenuous plasma produced in the vacuum vessel using an

electrode. The vacuum vessel wall being cleaned is biased

negatively against the electrode. This causes the ions in

the glow plasma to bombard and “scrub” the wall surface

free of contaminants. Finally, all the walls and graphite

tiles were coated with a thin layer of boron using trimethyl boron gas, which also helps keep heavy metals

from entering the plasma.

Other Work Underway

While striving to understand the physics behind

NSTX’s excellent plasma confinement and high-beta

performance, physicists are working on other fundamenNSTX

Continued from page 1
Page 3 PPPL NEWS • Winter 2001

tal goals. Among the most important of these are experiments relating to Coaxial Helicity Injection (CHI) and

High Harmonic Fast Waves (HHFW). If successfully

applied, CHI could lead eventually to the elimination of

the central solenoid, resulting in smaller, more powerful

fusion reactors. HHFW will heat plasma electrons to high

temperatures and sustain plasma current needed for steadystate fusion reactors.

State-of-the-art Spherical Torus

In a state-of-the-art spherical torus, the plasma current essential for start-up, heating, and confinement is

induced by rapidly reversing the current in a solenoid

running through the hole at the center of the vacuum

vessel. This coil occupies space, which could be used

more productively for additional toroidal windings, yielding a stronger toroidal magnetic field. For example,

doubling the toroidal magnetic field could result in as

much as 16 times the fusion power output. CHI, a method

of noninductive start-up, involves the establishment of

voltage between the center column and the vacuum vessel

outer wall. Electrical breakdown occurs propelling a

plasma ring into the chamber resulting in the creation of

a toroidal plasma. Separation of the plasma from the wall

occurs by means of magnetic reconnection, a phenomenon under study in PPPL’s Magnetic Reconnection

Experiment, as well in NSTX. To date, NSTX researchers

have been able to start up a plasma current of 0.26 million

amperes. Their goal is 0.50 million amperes or more.

NSTX is the first device of its size to test the physics

of HHFW. HHFW heats electrons and maintains plasma

current using a plasma wave at many times the frequency

with which ions gyrate around the magnetic field. Strong

electron heating using HHFW was observed for the first

time in recent NSTX experiments. Electron temperature

was increased from about 4 million degrees to above 10

million degrees Centigrade using 2 megawatts of power.

NSTX Program Director Martin Peng said, “It is encouraging to already have achieved good electron heating. We

look forward to exploring the new and rather intriguing

properties of HHFW and learning how to utilize this

method in spherical torus and other high-beta plasmas.”

In the mid-1980s, experiments on TFTR verified the

existence of the theoretically predicted bootstrap current,

which can sustain itself when the plasma pressure is high.

If NSTX experiments establish the effectiveness of CHI,

it may be used in conjunction with bootstrap plasma

current and HHFW to allow steady-state operation of a

fusion power plant. NSTX researchers hope to determine

if the bootstrap current will start automatically, or will

require a small seed current of a few percent of the total.

Bootstrap current may ultimately account for as much as

70 percent of the total plasma current flowing in NSTX.

Intriguing Experimental Results

The next NSTX experimental campaign is scheduled

to begin in February. “With many intriguing experimental results coming out of NSTX, as well as new capabilities being implemented, clearly there are far more experiments we would like to conduct than the available machine time and resources will permit. Obviously we

would like to explore and increase our understanding of

the high-beta plasma regime. We must continue the

development of key spherical torus reactor tools, such as

CHI and HHFW. So we must choose carefully to come up

with an optimized run plan,” Ono said. ●

From left, Joel Hosea, Dave Swain, Ben LeBlanc, Randy Wilson,

Bob Pinsker, and Jon Menard stand in front of the High Harmonic

Fast Waves transmission lines at NSTX.
PPPL NEWS • Winter 2001 Page 4

A Tribute to Mel Gottlieb, Former PPPL Director

Former PPPL Director

Melvin B. Gottlieb, an

international leader in the

field of research on fusion

energy, died on December 1

in Haverford, Pennsylvania.

He was 83.

Gottlieb, Director of

PPPL from 1961-1980, was

known for his tireless dedication to the fusion concept and

for his constant inspiration to

the fusion program worldwide, as well as for his leadsion, fusion, and solar. The question has always been:

How much is it going to cost? If it costs ten times existing

levels, we’re obviously going to have a great deal of

trouble supporting present population levels at the present

standard of living. The attainment of an economic, environmentally acceptable energy source is of enormous

importance for the future of mankind.”

Gottlieb led the Laboratory at an exciting time. In the

mid-1960s, initial experimental results from the Soviet

Union pointed to a new path to the very high-temperature

plasmas needed for making fusion energy. Under

Gottlieb’s leadership, the Laboratory took the international lead in extending these results, passing quickly

through three generations of highly successful tokamak

experiments. The Tokamak Fusion Test Reactor, whose

construction started under Gottlieb, produced a worldrecord plasma temperature of 510 million degrees centigrade and a record 10.7 million watts of fusion power.

Legacy of Plasma Science

PPPL Advanced Reactor Concepts Head Dale Meade

said, “Mel Gottlieb left a legacy of plasma science and

scientists that will carry the torch of plasma physics and

fusion energy forward for generations to come. Mel’s

wisdom and guidance were crucial in leading the U.S.

fusion program from the shadows of the post-World War

II era through the turbulence of the 1960s into the energetic fusion program of the 1980s. Mel’s personal warmth

and genuine concern nurtured and inspired generations of

scientists and staff at the Princeton Plasma Physics Laboratory. We will miss him greatly, and we will remember

him always as an inspiring leader, an insightful scientist,

and a close personal friend.”

Indeed, Gottlieb, known as “Mel” to everyone, is

remembered as much for his warm personal style as for

his insightful scientific leadership. His thoughtfulness

and calm — often expressed by putting his reassuring arm

around the shoulder of an over-stressed researcher — is a

cherished memory at PPPL.

“Mel was one of the finest people I have ever had the

pleasure of meeting and working with. There just are not

enough words to express what a great person he was. He

will be deeply missed by all who knew him,” said PPPL

Benefits Manager Bobbie Forcier.

Information Services Head Anthony DeMeo recalled

Gottlieb as a kind man who openly cared about the

welfare of PPPL staff. “Mel had a unique sensitivity to the

feelings and problems of his staff. For example, if he

Melvin B. Gottlieb

ership and for being the consummate “people person.”

“Mel was deeply loved at PPPL. My warmest memory

is of his support for me as a graduate student, struggling

to help Harold Eubank with the neutral injection experiments on the ATC [Adiabatic Toroidal Compressor]

machine, around 1975. His calm assurance and easy good

humor seemed to suggest that we would, indeed, get the

needed ‘typical data,’ sooner rather than later,” recalled

PPPL Director Rob Goldston.

Added Advanced Projects Head John Schmidt, “When

I came to PPPL, I decided to accept a postdoctoral

position here rather than more lucrative and permanent

positions at other fusion laboratories. A significant reason

for this was the impression Mel left on me. I obviously

have never regretted the decision. Mel stood very tall

physically, as a scientist, and as a fusion leader.”

During his 26-year association with PPPL, Gottlieb

saw the Laboratory grow from a small contingent of

investigators to a full-blown experimental facility on the

leading edge of magnetic fusion research. Under his

leadership, the Laboratory’s budgets expanded from $7

million during the early 1970s to $100 million in 1980.

Said former PPPL Director Harold Furth, “I think of Mel

as a benign gravitational force, which held world fusion

research together during its most thriving years.”

Throughout the growth of research projects, budgets,

and staff, he stressed the importance of explaining to the

layperson what fusion scientists were doing and why they

were doing it, without using highly technical language.

“Since we are publicly supported, we have a duty to the

public to make our ideas clear, our hopes clear, our

dreams clear,” said Gottlieb in 1980.

Asked then about the nation’s energy options, he

answered, “The long-term solutions for energy are: fis-
Page 5 PPPL NEWS • Winter 2001

Melvin B. Gottlieb is pictured with employees of PPPL, where he was Director

from 1961 through 1980. Gottlieb’s hand rests on a torus, representing the

donut shape of the magnetic confinement chambers used in fusion research

during his tenure.

learned that you or a member of your family was ill, he

never forgot to ask how things were going,” DeMeo said.

Cathy Howard, now retired, was Mel’s administrator

from 1974 through 1980 and she added, “I spent six years

by Mel’s side. He was a warm and compassionate leader

who believed in equality and practiced it by conducting an

‘open door’ policy for all, regardless of position or stature

in the organization. There was always time, even during

the busiest of schedules, for a kind word to put in perspective an individual’s

view of his or her problem. I remember during a very hectic and

stressful period of time

at the Lab when Mel

walked me to the large

office window which

overlooked the adjacent

woods and said, ‘Cathy,

everyone should take

time to smell the roses.’

He touched many lives

in this way, and, he occupied a very important chapter in my life.

He will be missed by

all who had the privilege of knowing him.”

Gottlieb, who was

educated at the University of Chicago and also

had been Professor of

Astrophysical Sciences

at Princeton University,

devoted considerable

time during his career

to working toward better understanding and

cooperation with other

nations in the development of fusion power.

The fusion program at

Princeton was classified until 1958. Thereafter, the program became international, involving cooperation and sharing of information. Lab

personnel including Gottlieb made frequent trips to meet

with scientists abroad and encouraged extended visits

here by foreign scientists.

During his tenure as Director at PPPL, Gottlieb was

also involved in high-level discussions with government

officials responsible for energy policy in many countries,

including France, England, Germany, Italy, Norway,

Japan, China, South Korea, Spain, Brazil, Canada,

U.S.S.R., and the European Economic Community. He

was a member of the U.S. Fusion Power Coordinating

Committee; the U.S.-U.S.S.R. Joint Committee on Atomic

Energy; the U.S.-People’s Republic of China Committee

on Fusion Cooperation; and the U.S.-Japan Fusion Cooperation Committee. In 1971, he was a recipient of the

North Atlantic Treaty

Organization (NATO)

Senior Foreign Fellowships in Science.

At the national

level, Gottlieb was active in many organizations whose purposes

included finding alternative safe sources of

energy. He had a long

association with the

American Physical Society and was founder

and first chairman of

its Plasma Physics Division. In 1980, he was

Vice Chairman of its

panel on Public Affairs. He was also a

member of the American Nuclear Society

and of Scientists and

Engineers for Safe Energy.

After his retirement from the Laboratory, Gottlieb continued consulting in his

field and, from 1980-

1992, served as Chairman of the Nuclear

Oversight Committee

of the Public Service

Electric and Gas Company of New Jersey.

Gottlieb is survived by his wife, Golda, whom he married in 1948; his

daughter, Paula Bastian, of Cedar Run, New Jersey; two

grandchildren, Will and Mary Kate Bastian; and two

nephews, David and Edward Mehlman, of Chicago. He

was pre-deceased by his daughter, Martha, who died in an

automobile accident in 1986. ●
PPPL NEWS • Winter 2001 Page 6

Francis “Rip” Perkins

From left are Kaul recipients Ronald Bell and Edmund Synakowski

and PPPL Distinguished Engineering Fellow Charles Neumeyer.

Francis “Rip” Perkins (pictured at right) received the PPPL Distinguished Research Fellow award via videoconference.

Kaul and Distinguished Fellow Awards Given

On November 2, PPPL Director Rob Goldston presented awards to four PPPL researchers. Ronald

Bell and Edmund Synakowski received the Kaul Foundation Prize for Excellence in Plasma Physics and Technology Development. Francis “Rip” Perkins and Charles

Neumeyer were named PPPL Distinguished Research

and Engineering Fellows, respectively. The four recipients were honored during a ceremony and reception

following Goldston’s State-of-the-Lab talk.

The Kaul award recognizes Bell and Synakowski for

novel measurements of the dynamics of hot ionized

gases, or plasmas. By modifying the flow of plasma

confined by magnetic fields, they found that the efficiency of the magnetic field in confining the plasma’s

heat can be altered and improved. Such flows act on

plasma turbulence, the underlying cause of heat loss from

these plasmas. The work suggests that generating plasma

flows in a fusion reactor might increase the reactor

efficiency, thus reducing its cost and size.

Perkins, who is on long-term assignment at General

Atomics in San Diego, received

the PPPL Distinguished Fellow

Award for his outstanding contributions in many critical areas

of plasma physics research with

applications in fusion, basic

plasma physics experiments, and

ionospheric physics, and for leadership in an international collaborative effort to document and

assess the physics basis of a next-step burning plasma

experiment. He was further honored for contributing

prominently to graduate education in plasma physics.

Neumeyer, the lead project engineer for the National

Spherical Torus Experiment (NSTX), received the PPPL

Distinguished Engineering Award for contributions and

technical leadership of the engineering effort to design

power systems for several magnetic fusion devices, including the Tokamak Fusion Test Reactor, the Tokamak

Physics Experiment, and NSTX, and for extraordinary

creativity and accomplishments in the development of

control systems for fusion devices. ●

On November 2, PPPL Director Rob

Goldston delivered his annual “Stateof-the-Lab” address to staff in a packed MBG

Auditorium. Goldston lauded the Lab’s research accomplishments, as well as the goals

and successes of our external relations efforts

and operations, stressing that PPPL’s programs

were “off and flying.” The talk was followed

by an ice-cream reception in the Lobby. At

right is Goldston giving the address. ●

The State of the Lab ...
Page 7 PPPL NEWS • Printed on recycled paper. Winter 2001

On October 24, President Clinton named 59 young

researchers — including Zhihong Lin, a physicist

at PPPL — as recipients of the fifth annual Presidential

Early Career Awards for Scientists and Engineers

(PECASE). This award is the highest honor bestowed by

the United States government on young professionals at

the outset of their independent research careers. The

researchers received their awards during a White House

ceremony.

Established by President Clinton in February 1996,

the award embodies the high priority the Administration

places on producing outstanding scientists and engineers

ready to contribute to all sectors of the economy. Eight

Federal departments and agencies join together annually

to nominate the most meritorious young scientists and

engineers who will broadly advance the science and

technology that will be of the greatest benefit to fulfilling

the agencies’ missions.

“These extraordinarily gifted young scientists and

engineers represent the best in our country,” President

Clinton said. “Through their talent, ability, and dedication, they will quicken the pace of discovery and put

science and technology to work advancing the human

condition as never before.”

The young scientists and engineers receive up to a

five-year research grant to further their study in support of

critical government missions. The Federal agencies inPresident Honors PPPL Scientist Lin

Lin Also Receives Department of Energy Early Career Award

Zhihong Lin

volved include: the Departments of Agriculture, Commerce, Defense, Energy,

Health and Human Services,

Veterans Affairs, the National

Aeronautics and Space Administration, and the National

Science Foundation.

Also on October 24, Ernest

J. Moniz, Under Secretary of Energy, Science and Environment, presented Lin and three others with the Department of Energy’s Office of Science Early Career Award

in Science and Engineering during a Department reception prior to the White House ceremony.

Both the Presidential and Department of Energy

awards cited Lin for “performing advanced simulations

with unprecedented realism and resolution leading to

results demonstrating the positive impact of modern

massively parallel computers and for outstanding contributions to improved understanding of plasma turbulence.”

Lin’s goals are to advance the physics understanding

of transport processes in magnetically confined, hightemperature plasmas and to demonstrate the exciting

discoveries that are made possible by the application of

modern, massively parallel computers in challenging

areas of plasma physics research. ●

American Nuclear Society Awards Williams

Michael Williams is the recipient of last year’s Outstanding Achievement Award from the American

Nuclear Society’s Fusion Energy Division. Williams is

Head of the Engineering and Technical Infrastructure

Department at PPPL. He received the award October 18

during the American Nuclear Society’s 14th Topical

Meeting on the Technology of Fusion Energy in Park

City, Utah. The award recognizes Williams’ longstanding

research and leadership in PPPL’s Poloidal Divertor

Experiment, Tokamak Fusion Test Reactor (TFTR), and

National Spherical Torus Experiment (NSTX) projects.

It is the most prestigious award from the society’s

Fusion Energy Division and is presented to a member in

recognition of exemplary individual achievement requiring professional excellence and leadership of high caliber

in the fusion science and engineering area.

Michael Williams

Williams, who is also

Deputy Director of the NSTX

project at PPPL, led several

project teams and served as the

Deputy Project Head of TFTR

from 1992 until the project was

closed down in 1997.

Williams has been Head of

the PPPL Engineering and

Technical Infrastructure Department since 1991, where he

is responsible for managing all

technical engineering and computing resources at the Lab. He came to PPPL in 1976

after graduating magna cum laude from Rutgers University with a bachelor’s degree in electrical engineering. ●
PPPL NEWS • Winter 2001 Page 8

The U. S. Department of Energy’s (DOE’s) National Laboratories house world-class facilities where

more than 30,000 scientists and engineers perform cutting-edge research spanning DOE’s science,

energy, national security, and environmental quality missions. Interested in the latest achievements of

the National Laboratories? Then visit the DOE Pulse at: http://www.ornl.gov/news/pulse/. DOE Pulse

is distributed twice each month. Each issue includes research highlights, updates on collaborations

among laboratories, and profiles of individual researchers.

Photo by Dietmar Krause

Energy Secretary Visits PPPL

On October 25, Bill Richardson (above), who was the U.S. Energy Secretary then, brought welcome news to PPPL, announcing a five-year

extension of the contract between Princeton University and the U.S. Department of Energy for the operation of the Laboratory. Richardson

made the announcement to a large assembly of PPPL personnel, media, and visitors at the MBG Auditorium.