FusionWiki - User contributions [en]

Forum of Small Stellarators

2025-07-17T14:24:43Z

Smoniewski: Correct email list subscription email

The Forum of Small Stellarators is a voluntary and informal group of scientists interested in research with small stellarators. "Small" is deliberately undefined, but usually applies to devices that are not pushing the frontiers of performance.

== Motivation ==
* There is renewed global interest in small, affordable, student-oriented stellarators.
* Small projects have less people/resources, inherent difficulties due to small size, but great potential to benefit from shared experience.

== Goal ==
This Forum should be a resource to discuss:
* compelling physics questions (not pushing <math>n T \tau</math>)
* engineering tips and hardware choices
* diagnostic challenges in small devices
* experiment configuration and design
* cross-device comparisons

== Activities ==
* Email list: to join, send "subscribe" to forum-of-small-stellarators-request at ipp.mpg.de
** Archive [https://listserv.gwdg.de/pipermail/forum-of-small-stellarators/ available here]
* Irregular meetings

== Meetings ==

* [[FoSS: ISHW2024|24th International Stellarator Heliotron Workshop, Hiroshima, Japan, September 2024]]
* [[FoSS: HiddenSymmetries2025|Simons Hidden Symmetries and Fusion Energy Retreat, Madison, Wisconsin, July 2025]]

FoSS: HiddenSymmetries2025

2025-07-03T08:16:20Z

Smoniewski: /* Agenda */

Uncoordinated Working Group Meeting as a satellite meeting to the Simons Hidden Symmetries and Fusion Energy Retreat in Madison, WI on 18 July, 2025.

== Agenda ==
* ~ 2 hours for group presentations, 15 minutes including questions per group.
** Yasuhiro Suzuki
** Joaquim Loizu - Polaris
** Georg Harrer (remote) - STAR_Lite
** Caoxiang Zhu (remote)
** Christopher Albert - CHEAPOS
** Ken Hammond - MUSE
** Paul Huslage - EPOS
** Thomas Gallenberger - ETOS
** Antoine Baillod - CSX
* short break
* discussion time
** address comments that come up during the Wednesday session "Forum of Small Stellarators - What can they offer"
** discussion of configurations and flexibility in small stellarators

FoSS: HiddenSymmetries2025

2025-07-02T15:10:00Z

Smoniewski: Created page with "Uncoordinated Working Group Meeting as a satellite meeting to the Simons Hidden Symmetries and Fusion Energy Retreat in Madison, WI on 18 July, 2025. == Agenda == * ~ 2 hours for group presentations, 15 minutes including questions per group. ** Yasuhiro Suzuki ** Joaquim Loizu - Polaris ** Georg Harrer (remote) - STAR_Lite ** Caoxiang Zhu (remote) ** Christopher Albert - CHEAPOS ** Ken Hammond - MUSE ** Paul Huslage - EPOS ** Thomas Gallenberger - ETOS * short break *..."

Uncoordinated Working Group Meeting as a satellite meeting to the Simons Hidden Symmetries and Fusion Energy Retreat in Madison, WI on 18 July, 2025.

== Agenda ==
* ~ 2 hours for group presentations, 15 minutes including questions per group.
** Yasuhiro Suzuki
** Joaquim Loizu - Polaris
** Georg Harrer (remote) - STAR_Lite
** Caoxiang Zhu (remote)
** Christopher Albert - CHEAPOS
** Ken Hammond - MUSE
** Paul Huslage - EPOS
** Thomas Gallenberger - ETOS
* short break
* discussion time
** address comments that come up during the Wednesday session "Forum of Small Stellarators - What can they offer"
** discussion of configurations and flexibility in small stellarators

Forum of Small Stellarators

2025-06-23T15:19:21Z

Smoniewski: /* Meetings */ Add Madison 2025

The Forum of Small Stellarators is a voluntary and informal group of scientists interested in research with small stellarators. "Small" is deliberately undefined, but usually applies to devices that are not pushing the frontiers of performance.

== Motivation ==
* There is renewed global interest in small, affordable, student-oriented stellarators.
* Small projects have less people/resources, inherent difficulties due to small size, but great potential to benefit from shared experience.

== Goal ==
This Forum should be a resource to discuss:
* compelling physics questions (not pushing <math>n T \tau</math>)
* engineering tips and hardware choices
* diagnostic challenges in small devices
* experiment configuration and design
* cross-device comparisons

== Activities ==
* Email list: to join, send "subscribe" to forum-of-small-stellarators at ipp.mpg.de
** Archive [https://listserv.gwdg.de/pipermail/forum-of-small-stellarators/ available here]
* Irregular meetings

== Meetings ==

* [[FoSS: ISHW2024|24th International Stellarator Heliotron Workshop, Hiroshima, Japan, September 2024]]
* [[FoSS: HiddenSymmetries2025|Simons Hidden Symmetries and Fusion Energy Retreat, Madison, Wisconsin, July 2025]]

FoSS: ISHW2024

2024-10-29T13:37:49Z

Smoniewski: add link to FoSS

The 1st meeting of the [[Forum of Small Stellarators]] (1st Uncoordinated Working Group Meeting) took place as a satellite meeting to the 24th ISHW in Hiroshima, Japan on 12 September, 2024.

== Agenda ==
* Welcome and introduction
* ~ 1.5 hours for group introduction presentations. These should be 2-3 slide, <5 minute presentations that provide a brief project overview and any particular strategies to being relevant although small. Each will be followed by 5 minutes of questions / discussion.
** STAR_Lite, Hampton University
** Polaris, École Polytechnique Fédérale de Lausanne
** CSX, Columbia University
** ETOS, University of Wisconsin-Madison
** TJ-K, Universität Stuttgart
** ALPES, Technische Universität Graz
** University of Science and Technology of China
** EPOS, Max-Planck-Institut für Plasmaphysik, Garching
** HU-Heliac, Hiroshima University
** MUSE, Princeton Plasma Physics Laboratory
** Renaissance Fusion
** Heliotron-DR, Kyoto University
* ~ 30 minutes for a coffee break. Opportunity for continuing discussions and engineering questions that are not of general interest.
* ~ 1 hour for brainstorming small stellarator physics investigations and possible joint experiments.

== Discussion ==

=== training ===
* training students is a very important and common motivation
* as part of coursework, project management and teamwork can also be trained
* with so many small devices, we should consider collaboration as an important aspect of training
* interest in an arduino-mentality stellarator kit (proposed by F. Volpe)
** standardize a kit to make startup easy, but allow for flexibility
** would be good for exporting stellarators to places with a limited budget, engineering groups without the physics support
* related motivation: outreach
** can we develop some interesting experiments/experiences ?
** moving coils around ? moving a permanent magnet around ?
** something like [https://scied-web.pppl.gov/rgdx/ RGDX at PPPL] ?
*** web-browser-based control system, providing an experiment remotely
*** if also standardized, could have a common web interface for multiple devices (proposed by Y. Suzuki)
*** suggest a workshop or bootcamp for development of the interface
* any workshop by the Forum should probably have a strong education aspect

=== configuration design / physics investigations ===
* small devices are test bed for integrated design, single-stage optimization
* configuration exploration ? QA, QH, QP, QI, tokamak, RFP ?
** benefits of some good configurations are not trivial to demonstrate at small size when collisionally dominated
** can look at electrons at low pressure, demonstrate drift effects
* turbulence studies, zonal flows
** don't need a big machine, just a big gradient. Columbia had a 10cm linear device doing ITG studies. They had the advantage of open field lines. What are stellarator options to create a large gradient ?
** see validation work at TJ-K. also turbulence work at TORPEX.
** small devices are often studying interchange turbulence. interactions of interchange with energetic particles could be interesting.
** also should look at validation of fluid turbulence codes
* fast particle transport, if can inject dimensionally correct electrons ?
* validate neoclassical flow damping
* explore boundaries of MHD stability
* what is the value of long discharges in small devices ?
* the renormalization parameter in ISS04 hides the physics of deviation from the trend. a greater variety of devices in the database, even at lower performance, could provide this missing information.
* small devices are challenged by background neutral gas. can we make this an advantage ? some sort of plasma-neutral interaction study ? atomic physics ?
** but we don't need a stellarator to study the atom

=== diagnostics ===
* variety of diagnostics already being used on small stellarators, some of which are also suitable for fusion plasmas
** field line mapping common to all devices
** probe access is particularly good on small devices
** spectrometers
** magnetic diagnostics
** imaging
* what is the typical budget for diagnostics ?
** wide range, but often zero. they are secondary to an operating device
* consider shared diagnostics ?
** we are happy to get old diagnostics from other machines !
** sharing diagnostics often comes with a lot of paperwork. its not easy to share a fast camera or oscilloscope. but sharing a probe head is easy.
** you need a human to operate diagnostics. it is a natural area for people exchange
** simplest way to get started is to share information. start with sharing how to make diagnostics and how to analyze.
** Forum activity could be to create diagnostic kits. include information, part list, instructions for assembly, tools for analysis. then share people for expertise.
* what is used for data management at small devices ? MDSplus ?
** often use custom format, manual data management
** may be an area for collaboration. standardized data access would facilitate cross-machine comparisons

=== plasma generation ===
* can be expensive, but often determines physics capability of device
* radio frequency: can be used for microwave studies, mode conversion, current drive, generation of high-energy electrons ?
* helicon
* electric discharge ?
* MUSE puts a tesla coil outside the vessel, a fun method for outreach physics experiments with a glass vessel
* consider non-neutral plasma, easy to generate

FoSS: ISHW2024

2024-10-29T13:35:52Z

Smoniewski: /* training */

The 1st meeting of the Forum of Small Stellarators (1st Uncoordinated Working Group Meeting) took place as a satellite meeting to the 24th ISHW in Hiroshima, Japan on 12 September, 2024.

== Agenda ==
* Welcome and introduction
* ~ 1.5 hours for group introduction presentations. These should be 2-3 slide, <5 minute presentations that provide a brief project overview and any particular strategies to being relevant although small. Each will be followed by 5 minutes of questions / discussion.
** STAR_Lite, Hampton University
** Polaris, École Polytechnique Fédérale de Lausanne
** CSX, Columbia University
** ETOS, University of Wisconsin-Madison
** TJ-K, Universität Stuttgart
** ALPES, Technische Universität Graz
** University of Science and Technology of China
** EPOS, Max-Planck-Institut für Plasmaphysik, Garching
** HU-Heliac, Hiroshima University
** MUSE, Princeton Plasma Physics Laboratory
** Renaissance Fusion
** Heliotron-DR, Kyoto University
* ~ 30 minutes for a coffee break. Opportunity for continuing discussions and engineering questions that are not of general interest.
* ~ 1 hour for brainstorming small stellarator physics investigations and possible joint experiments.

== Discussion ==

=== training ===
* training students is a very important and common motivation
* as part of coursework, project management and teamwork can also be trained
* with so many small devices, we should consider collaboration as an important aspect of training
* interest in an arduino-mentality stellarator kit (proposed by F. Volpe)
** standardize a kit to make startup easy, but allow for flexibility
** would be good for exporting stellarators to places with a limited budget, engineering groups without the physics support
* related motivation: outreach
** can we develop some interesting experiments/experiences ?
** moving coils around ? moving a permanent magnet around ?
** something like [https://scied-web.pppl.gov/rgdx/ RGDX at PPPL] ?
*** web-browser-based control system, providing an experiment remotely
*** if also standardized, could have a common web interface for multiple devices (proposed by Y. Suzuki)
*** suggest a workshop or bootcamp for development of the interface
* any workshop by the Forum should probably have a strong education aspect

=== configuration design / physics investigations ===
* small devices are test bed for integrated design, single-stage optimization
* configuration exploration ? QA, QH, QP, QI, tokamak, RFP ?
** benefits of some good configurations are not trivial to demonstrate at small size when collisionally dominated
** can look at electrons at low pressure, demonstrate drift effects
* turbulence studies, zonal flows
** don't need a big machine, just a big gradient. Columbia had a 10cm linear device doing ITG studies. They had the advantage of open field lines. What are stellarator options to create a large gradient ?
** see validation work at TJ-K. also turbulence work at TORPEX.
** small devices are often studying interchange turbulence. interactions of interchange with energetic particles could be interesting.
** also should look at validation of fluid turbulence codes
* fast particle transport, if can inject dimensionally correct electrons ?
* validate neoclassical flow damping
* explore boundaries of MHD stability
* what is the value of long discharges in small devices ?
* the renormalization parameter in ISS04 hides the physics of deviation from the trend. a greater variety of devices in the database, even at lower performance, could provide this missing information.
* small devices are challenged by background neutral gas. can we make this an advantage ? some sort of plasma-neutral interaction study ? atomic physics ?
** but we don't need a stellarator to study the atom

=== diagnostics ===
* variety of diagnostics already being used on small stellarators, some of which are also suitable for fusion plasmas
** field line mapping common to all devices
** probe access is particularly good on small devices
** spectrometers
** magnetic diagnostics
** imaging
* what is the typical budget for diagnostics ?
** wide range, but often zero. they are secondary to an operating device
* consider shared diagnostics ?
** we are happy to get old diagnostics from other machines !
** sharing diagnostics often comes with a lot of paperwork. its not easy to share a fast camera or oscilloscope. but sharing a probe head is easy.
** you need a human to operate diagnostics. it is a natural area for people exchange
** simplest way to get started is to share information. start with sharing how to make diagnostics and how to analyze.
** Forum activity could be to create diagnostic kits. include information, part list, instructions for assembly, tools for analysis. then share people for expertise.
* what is used for data management at small devices ? MDSplus ?
** often use custom format, manual data management
** may be an area for collaboration. standardized data access would facilitate cross-machine comparisons

=== plasma generation ===
* can be expensive, but often determines physics capability of device
* radio frequency: can be used for microwave studies, mode conversion, current drive, generation of high-energy electrons ?
* helicon
* electric discharge ?
* MUSE puts a tesla coil outside the vessel, a fun method for outreach physics experiments with a glass vessel
* consider non-neutral plasma, easy to generate

FoSS: ISHW2024

2024-10-29T13:32:33Z

Smoniewski: /* Discussion */

The 1st meeting of the Forum of Small Stellarators (1st Uncoordinated Working Group Meeting) took place as a satellite meeting to the 24th ISHW in Hiroshima, Japan on 12 September, 2024.

== Agenda ==
* Welcome and introduction
* ~ 1.5 hours for group introduction presentations. These should be 2-3 slide, <5 minute presentations that provide a brief project overview and any particular strategies to being relevant although small. Each will be followed by 5 minutes of questions / discussion.
** STAR_Lite, Hampton University
** Polaris, École Polytechnique Fédérale de Lausanne
** CSX, Columbia University
** ETOS, University of Wisconsin-Madison
** TJ-K, Universität Stuttgart
** ALPES, Technische Universität Graz
** University of Science and Technology of China
** EPOS, Max-Planck-Institut für Plasmaphysik, Garching
** HU-Heliac, Hiroshima University
** MUSE, Princeton Plasma Physics Laboratory
** Renaissance Fusion
** Heliotron-DR, Kyoto University
* ~ 30 minutes for a coffee break. Opportunity for continuing discussions and engineering questions that are not of general interest.
* ~ 1 hour for brainstorming small stellarator physics investigations and possible joint experiments.

== Discussion ==

=== training ===
* training students is a very important and common motivation
* as part of coursework, project management and teamwork can also be trained
* with so many small devices, we should consider collaboration as an important aspect of training
* interest in an arduino-mentality stellarator kit (proposed by F. Volpe)
** standardize a kit to make startup easy, but allow for flexibility
** would be good for exporting stellarators to places with a limited budget, engineering groups without the physics support
* related motivation: outreach
** can we develop some interesting experiments/experiences ?
** moving coils around ? moving a permanent magnet around ?
** something like [https://scied-web.pppl.gov/rgdx/ RGDX at PPPL] ?
*** web-browser-based control system, providing an experiment remotely
*** if also standardized, could have a common web interface for multiple devices (proposed by Y. Suzuki)
*** suggest a workshop or bootcamp for development of the interface

=== configuration design / physics investigations ===
* small devices are test bed for integrated design, single-stage optimization
* configuration exploration ? QA, QH, QP, QI, tokamak, RFP ?
** benefits of some good configurations are not trivial to demonstrate at small size when collisionally dominated
** can look at electrons at low pressure, demonstrate drift effects
* turbulence studies, zonal flows
** don't need a big machine, just a big gradient. Columbia had a 10cm linear device doing ITG studies. They had the advantage of open field lines. What are stellarator options to create a large gradient ?
** see validation work at TJ-K. also turbulence work at TORPEX.
** small devices are often studying interchange turbulence. interactions of interchange with energetic particles could be interesting.
** also should look at validation of fluid turbulence codes
* fast particle transport, if can inject dimensionally correct electrons ?
* validate neoclassical flow damping
* explore boundaries of MHD stability
* what is the value of long discharges in small devices ?
* the renormalization parameter in ISS04 hides the physics of deviation from the trend. a greater variety of devices in the database, even at lower performance, could provide this missing information.
* small devices are challenged by background neutral gas. can we make this an advantage ? some sort of plasma-neutral interaction study ? atomic physics ?
** but we don't need a stellarator to study the atom

=== diagnostics ===
* variety of diagnostics already being used on small stellarators, some of which are also suitable for fusion plasmas
** field line mapping common to all devices
** probe access is particularly good on small devices
** spectrometers
** magnetic diagnostics
** imaging
* what is the typical budget for diagnostics ?
** wide range, but often zero. they are secondary to an operating device
* consider shared diagnostics ?
** we are happy to get old diagnostics from other machines !
** sharing diagnostics often comes with a lot of paperwork. its not easy to share a fast camera or oscilloscope. but sharing a probe head is easy.
** you need a human to operate diagnostics. it is a natural area for people exchange
** simplest way to get started is to share information. start with sharing how to make diagnostics and how to analyze.
** Forum activity could be to create diagnostic kits. include information, part list, instructions for assembly, tools for analysis. then share people for expertise.
* what is used for data management at small devices ? MDSplus ?
** often use custom format, manual data management
** may be an area for collaboration. standardized data access would facilitate cross-machine comparisons

=== plasma generation ===
* can be expensive, but often determines physics capability of device
* radio frequency: can be used for microwave studies, mode conversion, current drive, generation of high-energy electrons ?
* helicon
* electric discharge ?
* MUSE puts a tesla coil outside the vessel, a fun method for outreach physics experiments with a glass vessel
* consider non-neutral plasma, easy to generate

FoSS: ISHW2024

2024-10-25T15:12:15Z

Smoniewski: Page creation

Forum of Small Stellarators

2024-10-25T11:35:03Z

Smoniewski:

The Forum of Small Stellarators is a voluntary and informal group of scientists interested in research with small stellarators. "Small" is deliberately undefined, but usually applies to devices that are not pushing the frontiers of performance.

== Motivation ==
* There is renewed global interest in small, affordable, student-oriented stellarators.
* Small projects have less people/resources, inherent difficulties due to small size, but great potential to benefit from shared experience.

== Goal ==
This Forum should be a resource to discuss:
* compelling physics questions (not pushing <math>n T \tau</math>)
* engineering tips and hardware choices
* diagnostic challenges in small devices
* experiment configuration and design
* cross-device comparisons

== Activities ==
* Email list: to join, send "subscribe" to forum-of-small-stellarators at ipp.mpg.de
** Archive [https://listserv.gwdg.de/pipermail/forum-of-small-stellarators/ available here]
* Irregular meetings

== Meetings ==
[[FoSS: ISHW2024|24th ISHW, Hiroshima, Japan, September 2024]]

Forum of Small Stellarators

2024-10-25T10:08:13Z

Smoniewski:

The Forum of Small Stellarators is a voluntary and informal group of scientists interested in research with small stellarators. "Small" is deliberately undefined, but usually applies to devices that are not pursuing the frontiers of performance.

== Motivation ==
* There is renewed global interest in small, affordable, student-oriented stellarators.
* Small projects have less people/resources, inherent difficulties due to small size, but great potential to benefit from shared experience.

== Goal ==
This Forum should be a resource to discuss:
* compelling physics questions (not pushing <math>n T \tau</math>)
* engineering tips and hardware choices
* diagnostic challenges in small devices
* experiment configuration and design
* cross-device comparisons

== Activities ==
* Email list: to join, send "subscribe" to forum-of-small-stellarators at ipp.mpg.de
** Archive [https://listserv.gwdg.de/pipermail/forum-of-small-stellarators/ available here]
* Irregular meetings

== Meetings ==
[[FoSS: ISHW2024|24th ISHW, Hiroshima, Japan, September 2024]]

Forum of Small Stellarators

2024-10-23T12:35:40Z

Smoniewski: Page creation

== Motivation ==
* There is renewed global interest in small, affordable, student-oriented stellarators.
* Small projects have less people/resources, inherent difficulties due to small size, but great potential to benefit from shared experience.

== Goal ==
This Forum should be a resource to discuss:
* compelling physics questions (not pushing <math>n T \tau</math>)
* engineering tips and hardware choices
* diagnostic challenges in small devices
* experiment configuration and design
* cross-device comparisons

== Activities ==
* Email list: to join, send "subscribe" to forum-of-small-stellarators at ipp.mpg.de
** Archive [https://listserv.gwdg.de/pipermail/forum-of-small-stellarators/ available here]
* Irregular meetings

== Meetings ==
[[FoSS: ISHW2024|24th ISHW, Hiroshima, Japan, September 2024]]