All opinions expressed herein are those of the authors and should not be reproduced, quoted in publications,
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An international journal of news from the stellarator community
Editor: James A. Rome Issue 176 December 2021
E-Mail: James.Rome@ Phone: +1 (865) 482-5643
On the Web at
Carbon Dioxide, Fusion, and Stellarators
I. Introduction
The importance of fast and high-certainty development of
fusion energy is defined by the exponential increase in
both carbon dioxide emissions and the enhancement of the
atmospheric concentration of CO2, Fig. 1 [1]. When the
speed and certainty of development are the primary criteria,
the stellarator is the fusion concept of choice[2, 3].
The increased CO2 concentration is associated with an
increasing atmospheric temperature, ocean level, and
ocean acidity. Uncertainties in our understanding of the
impacts of these phenomena raise additional concerns.
Figure 1 implies that action must be taken, and 2050 is
generally taken as the date by which net CO2 emissions
must end [4, 5]. The focus has not been on controlling
atmospheric CO2 but on eliminating the use of fossil fuels
(coal, oil, and natural gas).
What is often not recognized is the enormous ratio
between the cost of deployment of an option for a solution,
to the cost of development of the option to the point of
deployment. A typical ratio of these costs is the one for
fusion energy, approximately a thousand. Only one
demonstration fusion power plant is required to determine
the properties of fusion power, but approximately ten
thousand fusion power plants are required to affect world
energy production.
The cost of deployment using existing options to achieve
net-zero emissions by 2050 is high. Page 47 of a 2021
International Energy Agency report [5] says $4 trillion per
year will be required by 2030. A hundred times smaller
expenditure, $40 billion per year, could provide better
options through well-organized development programs.
By comparison, the size of the world energy industry is
approximately $6 trillion per year.
In this issue . . .
Carbon Dioxide, Fusion, and Stellarators
Much emotion is expended on the dangers of carbon
dioxide, but solutions require reason and recognition of
facts: (1) The cost of developing options is approximately
a thousand times less than the cost of their deployment.
(2) Time scales involve two questions: (a) How quickly
can an option be demonstrated? (b) How quickly can the
required equivalent of thousands of units be built? Two
questions are implied: (1) What options would most fundamentally
change the carbon dioxide problem? (2) For
each option, how could it be demonstrated most quickly?
An option of fundamental importance is direct air capture
of carbon dioxide. The option that appears most attractive
for carbon-free energy production is the stellarator
fusion concept, which is poised for a rapid demonstration.
. .....................................................................................1
First announcement of ISHW2022
We are pleased to announce that the 23rd International
Stellarator/Heliotron Workshop (ISHW) will be held 20–24
June 2022 in Warsaw, Poland. ....................................9
Fig. 1. The rate of CO2 emissions is doubling approximately
every 30 years and the enhancement in the atmospheric
concentration of CO2 above its pre-industrial level
is doubling approximately every 40 years. This NOAA Climate.
gov graph by Rebecca Lindsey [1] was adapted from
the original by Howard Diamond (NOAA ARL). Atmospheric
CO2 data from NOAA and ETHZ. CO2 emissions
data from Our World in Data and the Global Carbon Project.
Stellarator News -2- December 2021
Controlling emissions alone will be expensive but it still
leaves the CO2 concentration above its present level for
centuries, Fig. 2 [6, 7]. The U.S. National Academy and
the British Royal Society state on page 22 of their 2020
report [8]: “Even if emissions of greenhouse gases were to
suddenly stop, Earth’s surface temperature would require
thousands of years to cool and return to the level in the
pre-industrial era.” These are times cales for climatechange
accommodation, not avoidance.
On 5 November 2021, U.S. Secretary of Energy Jennifer
Granholm announced [9] the goal of building a direct air
capture (DAC) and sequestration system at a gigaton level
by 2050 with a CO2 removal cost of less than $100/ton.
The envisioned cost of removal and sequestration is typically
given [6, 10] as $100 to $200 per ton of CO2, and
research is required to achieve costs even in this range.
To have a profound effect on arresting the level of CO2 or
the time cale for lowering that level requires a DAC system
comparable in scale to the 36 gigatons that are now
being emitted each year. This is also the maximum emission
rate under the different CO2 mitigation plans
described on page 33 of Ref. [5]. The removal of 36 gigatons
per year is far beyond what can be accomplished by
measures such as planting trees [6].
If a 1 gigaton DAC system can be built by 2050, it would
only be a matter of will whether a 36 gigaton system could
be completed shortly thereafter. At $100/ton, present emissions
could be removed for less than the $4 trillion per
year required to end emissions by 2050 as envisioned by
the International Energy Agency [5].
The effect on the time scale for maintaining or returning to
any earlier atmospheric concentration of carbon dioxide
using DAC is profound. When it is assumed that CO2
emissions are ended by mid-century, the sum of all CO2
emissions due to humans is approximately fifty times
larger than the 36 gigatons that are now being emitted per
year. A CO2 removal system that can remove as much carbon
dioxide in a year as the highest one-year emission
would eliminate any further increases in the level of atmospheric
CO2 once that system is available and reduce the
enhancement of the CO2 concentration on the time scale
of a lifetime, not millennia.
The time to develop a new option need not be too long to
be consistent with the 2050 date for the implementation of
a solution. It took only 15 years to go from the splitting of
uranium in a laboratory to fission-powered submarines.
Will and organization are critical. Fears associated with
World War II and the Cold War provided the necessary
will. General Groves and Admiral Rickover provided
required organizational skills.
Sufficient will exists for large expenditures to address the
CO2 problem. In 2020, one country, Germany, spent $38
billion subsidizing green energy [11]. Organization is
more difficult. Without appropriate organization, a
research program can expend arbitrarily large resources
and take an arbitrarily long time.
Since the cost of development is trivial compared to the
cost of deployment, a rational world would ask what
options would allow carbon dioxide issues to be addressed
with the greatest certainty, on the shortest possible time
scale, and with the least detriment to the world economy.
Two such options are the direct removal of carbon dioxide
[6, 10] and fusion energy [2, 3]. Without clairvoyance, an
optimal program must explore options that may never be
Page 4 of the 2019 U.S. National Academies report [6]
mentioned avoiding the moral hazard of “reducing humanity’s
will to cut emissions in the near term” by proposals
for research on attractive options. Discouraging the development
of better options not only seems irresponsible but
would likely delay the restoration of a desirable CO2 level.
Reason is a better guide than emotion in determining when
and how the switch from the development to the deployment
of the best options should occur.
What is meant by a desirable carbon dioxide level is subtle;
each level has winners and losers. For example, what
level is optimal for worldwide food production versus the
flooding of low-lying regions? In any case, global warming
sounds far less dangerous than global cooling—a new
ice age. The last ice age ended approximately 12 thousand
years ago. People have inhabited the Earth for more than
twenty times longer, and the Earth itself is three million
times older.
The optimal CO2 level is ultimately a political question.
The optimum is often assumed to be the pre-industrial
Fig. 2. An enhanced carbon dioxide concentration only
slowly decreases towards its natural level, see page 24 of
Ref. [6], which cites [7].
Stellarator News -3- December 2021
level. Based on the primary planning documents, a return
to the pre-industrial CO2 concentration would take millinnia
[8]. That is why the announcement by Secretary
Granholm [9] on direct air removal of CO2 is of such great
potential importance.
To be widely accepted, energy sources must be reliable
and consistent with an increasing worldwide standard of
living. Eliminating the use of fossil fuels before acceptable
alternatives are available is both expensive and counterproductive.
The February 2021 collapse in the electricity
grid in Texas and the late-summer 2021 lull in the North
Sea winds [12] illustrate problems that occur when insufficient
thought goes into ensuring system stability and providing
backups for intermittent energy sources.
The cost of energy is important, but long term reliability is
even more so. Being without electricity for home lighting
and heating during a few randomly occurring weeks a year
is unacceptable. It is even less acceptable for industry! The
higher cost of a reliable energy source may be offset by
efficiency measures. Unreliability can be addressed by
home or industrial generators, but they are polluting, inefficient,
and expensive.
Wind and solar are the widely acclaimed alternative to fossil
fuels. Their practicality is location dependent; they are
not universally applicable without long-distance transmission.
Their intermittency necessitates backup systems.
Batteries can be used for hours-long interruptions, but
long term interruptions, such as the lull in the North Sea
winds, require an alternative power source. Natural gas
turbines are the basis of the only system that is inexpensive,
has quick turn-on and turn-off time scales, and is not
location dependent. Nevertheless, even natural gas systems
require careful design for stability, as illustrated by
the Texas blackout. Natural gas could be replaced by a
manufactured carbon-free product, such as hydrogen. If
wind and solar were as reliable as often implied [13], the
use of the backup would be rare. In addition, the carbon
dioxide could be removed from the exhaust.
The only energy system that can be employed at the
required scale while not being intermittent and location
dependent is nuclear energy. Nuclear energy, whether fission
or fusion, has a low fuel cost but high capital cost.
Once built, the power plant should be operated as close to
full power for as large a fraction of the time as practical to
recover the expense of construction. Consequently,
nuclear energy is not a practical backup for wind and solar.
Fission energy has waste, safety, and proliferation issues,
which can be largely avoided with fusion, but fusion has
not yet been demonstrated.
Carbon dioxide control defines the need to develop fusion
energy with the highest certainty and in minimum time.
Section II outlines how this can be done and why the stellarator,
not the tokamak, provides the obvious path.
II. Fusion Energy
Two types, or isotopes, of hydrogen, deuterium (D) and
tritium (T), will react, called burning, to produce an ordinary
helium nucleus (an alpha particle) and a neutron as
well as a large amount of energy. For this to happen, the
temperature must be approximately 100 million degrees
Ceelsius, which in the conventional units of plasma physics
is 10,000 electron volts, 10 keV. At this temperature
the electrons and ions separate to form a plasma, which is
an ideal gas that is an excellent conductor of electricity.
The number density of the electrons and the ions is
approximately 1020 m−3, which implies that the plasma
has a pressure of approximately 3 atmospheres. Each electron
and ion moves approximately 10 km between interactions
with other particles that change its momentum and
energy. These interactions are called collisions. The plasmas
in fusion power plants have scales of a few meters;
the motion of particles on this scale is determined by the
classical mechanics of collisionless particles in large-scale
electric and magnetic fields. For energy release from the
D-T to be adequate to maintain a D-T burn in a power
plant, the confinement time of energy in the plasma must
be orders of magnitude longer than the time scale for collisions.
The implication is that the electron and ion velocities
will be in the Maxwellian distribution that is
characteristic of an ideal gas. Tritium does not naturally
occur in nature but can be produced by neutrons reacting
with lithium in a blanket that surrounds the plasma.
The plasmas in stellarators and tokamaks are toroidal,
Fig. 3. Magnetic field lines lie on nested toroidal surfaces.
The only way the plasma can escape is to drift or diffuse
across these surfaces. The magnetic surfaces in stellarators
can be defined by currents in coils that lie outside the
plasma (Fig. 3), but in tokamaks a current within the
plasma has an essential role in formation of these surfaces.
Tokamak plasmas can in principle be exactly axisymmetric;
stellarators must have helical shaping.
Confinement of the magnetic field lines and the particles
on toroidal surfaces would be ensured in tokamaks if their
toroidal symmetry were exact—including self-consistent
plasma effects. But their confinement requires careful
design for stellarators since stellarators cannot have an
exact continuous spatial symmetry. Nevertheless, the stellarator
path to a fusion power plant is far more certain and
faster than for a tokamak.
The attractiveness of stellarators for fusion power plants
follows from the dominance of the externally produced
magnetic field, which:
1. Provides robust passive stability.
2. Allows reliable computational optimization.
Stellarator News -4- December 2021
3. Has an order of magnitude more degrees of freedom
in the external magnetic field than in an axisymmetric
Most fusion experiments are tokamaks; the largest is the
ITER, now under construction at a cost of $20–$40 billion.
ITER was designed to produce net fusion power after
2035. Tokamaks operate in a nonlinear self-determined
state, which requires active control. Unfortunately, few
control knobs are available. Both diagnostics and controls
become far more limited in burning plasmas than in existing
tokamaks. Loss of control results in disruptions and
the transfer of the plasma current to relativistic-electron
carriers. Both can do major damage to the machine. A
solution is not known; an invention is required before
tokamak power plants are possible [2, 3]. The requirement
of an invention makes estimates of time and certainty
Recognition of the problems of tokamaks with relativistic
electrons (RE) and disruptions is increasing. As noted in a
2019 review [15]: “With ITER construction in progress,
reliable means of RE mitigation are yet to be developed.”
Machine damage from disruptions also appears more difficult
to mitigate than previously thought. In 2021, Nick
Eidietis, who is a co-chair of the ITER-appointed Disruption
Mitigation Task Force, reviewed the disruption situation
in tokamaks [16]. As noted in Ref. [17]: “Steering
tokamak plasmas is commonly viewed as a way to avoid
disruptions and runaway electrons. Plasma steering
sounds as safe as driving to work but will be shown to
more closely resemble driving at high speed through a
dense fog on an icy road. The long time required to terminate
an ITER discharge compared to time over which dangers
can be foreseen is analogous to driving in a dense
fog. The difficulty of regaining plasma control if it is lost
resembles driving on an icy road.”
Stellarators were thought to have a “fatal flaw” due to the
absence of toroidal symmetry. This can lead to a rapid drift
of the particles that form the fusion plasma across the
magnetic field lines and unacceptably limit the energy
confinement time—an even more fundamental problem
than tokamak disruptions. In 1981, Boozer [18] developed
a coordinate system and in 1984 a Hamiltonian description
[19] of particle drifts in those coordinates. These developments
showed that a symmetry in the magnetic field
strength confined particles as well as a symmetry in the
vector B that represents all three components of the magnetic
field. In 1988, Nührenberg and Zille [20] showed
that a stellarator can be designed so the magnetic field
strength B accurately approximates having a continuous
symmetry even though the vector B cannot. The “fatal
flaw” of stellarators was eliminated.
The most important result from the ($1 billion) Wendelstein
7X (W7-X) stellarator is that computational design
works for stellarators even through a major change in configuration
and scale [21]. Tokamaks are designed by
extrapolating from one generation of experiments to
another. The self-consistent nonlinear state of tokamak
plasmas gives no other option.
When time and certainty of success are critical, reliable
computational design is vastly preferable to empirical
extrapolationsfor the following reasons:
1. Experiments build in conservatism.
Even apparently minor changes in design are not pos-
Fig. 3. Both stellarators and tokamaks are toroidal, but stellarators have a helical twist and tokamaks are ideally axisymmetric.
The blue coils produce the magnetic field that confines the yellow plasma in the stellarator diagram. The magnetic
field that confines the purple plasma in the tokamak diagram [14] requires a current that flows toroidally in the plasma.
Stellarator News -5- December 2021
sible and therefore remain unstudied. Major changes
are risky even when going from one generation of
experiments to another.
2. Experiments are built and operated over long periods
of time.
Several decades are common. A fast-paced program is
inconsistent with many generations of experiments.
3. The cost of computational design is many orders of
magnitude smaller than building a major experiment.
Innovative conceptual designs of stellarator power
plants would cost ≈$10 million per year (≈2% of the
U.S. fusion program). Much better designs appear
4. Extrapolations are dangerous when changing physics
Tokamak examples are (i) plasma control in ignited
versus nonignited plasmas and (ii) the formation of a
current of relativistic electrons during a disruption.
The computational design of stellarators is not only desirable
but also required:
1. Well-confined magnetic field lines and particle drift
trajectories are not automatic as they are in axisymmetric
2. Design optimization is subtle because of the large size
of the optimization space.
This space is the 50 external magnetic-field distributions
that can be produced with the same efficiency as
the shaping fields of tokamaks. Efficiency means the
ratio of the magnetic field strength at the coils to that
at the plasma. A space of 50 degrees of freedom is too
large to be fully explored, but an unlimited frontier
invites discovery and invention.
3. Designs can consider attractive plasma states that
have no desirable tokamak analog.
Fueling by pellet injection could be eased by having
good confinement in only the outer third of the
plasma. Transport could be controlled using internal
transport barriers.
4. Unlike tokamaks, coils that allow open access to the
plasma appear possible, Fig. 4 [22], and hopefully
computation can find more optimal designs..
The efficiency of magnetic field distributions is limited
because the coils must be located behind the blankets and
shields that surround the plasma. The blanket is where tritium
is produced from lithium, and the shields protect the
superconducting coils from neutron damage. The choice
of magnetic field distributions that are controlled in a
design is determined not only by their efficiency of production
but also by the sensitivity of plasma properties to
them. This sensitivity can differ by orders of magnitude
and, especially in tokamaks, in sometimes surprising
ways. The issues of efficient field production and plasma
sensitivity are discussed in Ref. [23].
As noted, tokamak plasmas require far more control, but
the degrees of freedom to provide that control are far
fewer. The currents in the poloidal field coils of a tokamak,
Fig. 3, must depend on time. A major control problem
arises since the time scale for magnetic fields to
penetrate through the blanket and shields, approximately
half a second, can be far longer than the time scale for the
plasma to evolve in undesirable situations. In addition, the
natural decay time for the plasma current in ITER is 1000
seconds. To shut down the plasma faster requires pulling
magnetic flux out of the plasma using the transformer
coils. This can be much faster, but creates current profiles
in the plasma that can cause disruptions. Sixty seconds is
thought to be the fastest disruption-free shutdown time for
ITER [17]. The coil currents in stellarators need not
evolve but can do so when a better design results. Unlike
magnetic fields produced by plasma currents, those produced
by external coils do not need to be removed from
the plasma to shut the plasma down.
Empirical confinement times for energy in stellarators and
tokamaks fit the same scaling law, Fig. 5, which is given
by gyro-Bohm diffusion within a dimensionless scaling
factor [2]. Extrapolations of the transport of electrons and
ions observed in long-pulse W7-X experiments yield
attractive reactors.
The required energy confinement to maintain a D-T burn
in a fusion power plant depends on the plasma temperature,
T. Assuming the plasma transport is gyro-Bohm and
the ratio of the plasma to the magnetic field pressure is
held fixed, the optimal temperature is T ≈10 keV, Fig. 6.
Stellarator power plants could operate at T ≈10 keV, but
Fig. 4. The large helical ripple in the magnetic field
required in stellarators can be exploited to allow easy
access to the plasma chamber and quick changes of internal
components. Although no one has optimized stellarator
coils for open access, Yamaguchi’s solution [22] proves
that this is possible. Mathematics guarantees that all of the
coils except the plasma-encircling red coil can be replaced
by coils shaped like picture frames. Picture frame coils can
be located in removable wall sections.
Stellarator News -6- December 2021
current drive and the Greenwald limit on tokamak density
can push tokamak power plants [3] to a much higher temperature
T ≈40 keV. This and the limited plasma control
make obtaining adequate confinement much more difficult
in tokamaks than in stellarator power plants.
Toroidal plasmas, whether in tokamaks or stellarators,
need a system (a divertor) that controls plasma contact
with the surrounding chamber walls. Divertors have
requirements that appear contradictory. They must concentrate
the outflowing plasma that has reached the plasma
edge into localized divertor chambers where pumps are
located. These pumps remove the helium ash and maintain
a steady-state balance with the D-T fueling. On the other
hand, divertors cannot concentrate the outflowing heat
into the divertor chambers because the average power density
on the walls should be as high as technically possible
to reduce the cost of fusion power. The Watts of nuclear
power striking a square meter of the walls must be sufficient
to pay for all the structures behind it.
The solution to the contradictory demands on a divertor is
detachment, which means that the plasma flowing towards
the divertor chambers radiates most of its energy content
before it enters the chamber.
Fig. 5. Empirically, tokamaks and stellarators have the
same scaling of their energy confinement time. Both obey
what is called gyro-Bohm scaling [2].
Fig. 6. The empirical behavior of transport and the temperature
dependence of the deuterium-tritium reactivity
corrected for bremsstrahlung losses makes the required
confinement of a self-sustaining fusion burn highly dependent
on the plasma temperature T.
Fig. 7. Resonant divertors require a specific twist of the
magnetic field lines so that an island in the magnetic field
lines can be produced to define the divetor. W7-X uses this
type of divertor.
Fig. 8. Stellarators tend to have an outermost confining
magnetic surface. Outside that surface, magnetic field lines
tend to strike the walls in helical stripes [24], which can be
used to define the location of the divertor chambers.
Stellarator News -7- December 2021
Two types of divertors have been considered for stellarators:
resonant and nonresonant.
Resonant divertors utilize an island chain at the plasma
edge, Fig. 7. They have been studied in W7-X and have
demonstrated attractive long-term detachment properties
[21]. The achievement of robust steady-state detachment
remains a major issue for tokamaks.
Nonresonant divertors [24] arise naturally in a stellarator,
Fig. 8. There is an outermost magnetic surface that confines
the plasma. Outside that surface are generally cantori
which define tubes of magnetic flux that go from the
plasma edge to the divertor chambers [25]. In numerical
simulations, these flux tubes are observed to strike the
same places on the wall (in helical stripes) even when
important properties of the field are changed [26].
A major issue for both tokamaks and stellarators is the
production of adequate tritium in the blanket [27]. As discussed
in Ref. [3], stellarators have properties that better
address a number of the tritium self-sufficiency issues:
1. Absence of disruption forces allows thinner structures
and more tritium production.
2. Open access coils, Fig. 4, allow fast changes in blanket
structure, which makes studies of multiple designs
3. The radial dependence of transport could be adjusted
to make tritium use more efficient using shallow pellet
III. Summary
Major studies of the problem of carbon dioxide increase,
such as Refs. [4, 5], focus on a strategy of ending the use
of fossil fuels by 2050. This strategy ignores the millennia-
long natural persistence of CO2 once emissions end
and the low cost of developing better options relative to
the cost of deploying existing options.
Emotional calls that focus on a fast elimination of fossil
fuels to end climate change mislead the public. Without
the deployment of a large-scale system for DAC of carbon
dioxide, the effects of CO2 on the climate will be worse
during the next several centuries than they are now.
Fortunately, the need of DAC of CO2 has been recognized
[9], and perhaps efforts to solve the problem of an elevated
CO2 concentration will not be further impeded by the
moral hazard of “reducing humanity’s will to cut emissions
in the near term” [6].
Arbitrarily large sums can be expended and time wasted
on ill-organized development programs. The same can be
said for ill conceived deployments. Development and
deployment can occur on a fast time scale when there is
will and appropriate organization. This is illustrated by the
development of a COVID-19 vaccine and the distribution
to all American adults who wanted it in just over a year.
Decisions on which options should have expedited development
and when to deploy the best existing options are
not simple. These decisions should be based on reason
rather than emotion. Whatever the decisions may be, careful
planning and organization are required in their implementation.
Nuclear energy is the carbon-free source that is neither
intermittent nor localized in its places of application. Fission
energy could be deployed now on whatever scale is
needed, and fission power plants could be made more suitable
to the varied needs by further development. Nevertheless,
fusion energy has fundamental advantages in
avoiding dangers such as the proliferation of nuclear
weapons and long-lived radioactive wastes.
The fusion of deuterium and tritium is in principle the
most attractive option for producing carbon-free energy.
Stellarators are far better poised than tokamaks for a fast
and more certain development of a fusion power plant.
The annual cost of an aggressive but well-organized minimal-
time program to develop fusion energy would likely
be less than $10 billion. Typical designs for fusion power
plants produce a gigawatt of electricity and should cost no
more that $10 billion to be cost competitive with fission. A
ten-year construction period would cost a billion dollars a
year. The first of a kind machine may cost several times
more, and several machines of different types should be
built to mitigate risks. Research on material and construction
concepts could be a billion dollars a year.
$10 billion dollars per year is a substantial amount of
money but much less than the $38 billion that Germany
spends each year subsidizing green energy [11] and tiny
compared to the $4 trillion a year said to be needed to terminate
the use of fossil fuels [5]. An aggressive fusion
program would have technological spinoffs just as did the
eight-year Apollo program to land and return a person
from the moon. Obvious areas are better high-temperature
superconductors, improved techniques for three-dimensional
manufacture of large components, and better materials.
The first three to five years of a minimum-time stellarator
program should be focused on computational conceptual
design, which would cost approximately $10M per year—
a thousand times less than the annual cost of the construction
period of a minimal-time fusion program. Ten million
dollars per year is only about 2% of the present U.S.
fusion program.
The absence of an aggressive program on the computational
conceptual designs of stellarators anywhere in the
world defies reason. Perhaps the recognition of the importance
of option development in Secretary Granholm’s
announcement on DAC of CO2 [9] will foster rational
Stellarator News -8- December 2021
considerations on broader questions associated with the
solution to the CO2 problem.
This work was supported by the U.S. Department of
Energy, Office of Science, Office of Fusion Energy Sciences
under Award Numbers DE-FG02-95ER54333, DEFG02-
03ER54696, DE-SC0018424, and DE-SC0019479,
and by grant 601958 within the Simons Foundation collaboration
“Hidden Symmetries and Fusion Energy.”
Allen H Boozer
Columbia University, New York, NY 10027
E-mail ahb17@
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Stellarator News -9- December 2021
First announcement of ISHW2022
We are pleased to announce that the 23rd International
Stellarator/Heliotron Workshop (ISHW) will be held 20–
24 June 2022 in Warsaw, Poland.
The workshop will be organized by the Institute of Plasma
Physics and Laser Microfusion (IPPLM).
The details can be found on the website:
which will be continuously updated.
Topics discussed will include:
• 3D effects on transport and confinement
• Impurity sources and transport
• Plasma edge physics and plasma-wall interaction
• Energetic particles, MHD and plasma stability
• Theory and simulation
• Energy, particle and momentum transport
• Stellarator and Heliotron reactor design studies
• 3D effects in tokamaks and reversed field pinches
We are looking forward to seeing you in Warsaw!
David Gates, chair
IPC membership to be announced
Local Organization Committee (LOC):
Barbara Bienkowska
Piotr Chmielewski
Tomasz Fornal
Marta Gruca
Monika Kubkowska, chair
Anita Pokorska

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