Cyclotron project management design rules

They are run only on Friday evenings and Saturday, and - if demands are high - on Sundays. For these bombardments a longer cooling time is required. A nominal time of 25 to 30 minutes is set

McWalters et al., Radiation Exposures of Personnel at the 60-inch Cyclotron — UCRL-8276 (1958) — p. 10

Editorial note, tabletop extrapolation: ENERGY SCOPE: Crocker's figures are (d,n) activation at tens of uA and ~20 MeV. Sub-MeV deuterons still make neutrons - D(d,n)3He and 9Be(d,n) are exothermic - so the analogue exists the day deuterium enters the machine (dg-121, dg-545). The scheduling pattern transfers either way: batch the nastiest operations (HV conditioning, any future deuteron or neutron work) into planned windows with a defined stand-down, rather than interleaving them with routine bench time.

Inasmuch as the equivalent diameter of the pole pieces is 44 in., the machine is more appropriately identified as the 44-in. cyclotron.

Howard (ed.), Electromagnetic Research Division Semiannual, period ending 20 March 1953 — ORNL-1531 (1953) — p. 20

Editorial note, tabletop extrapolation: The reference machine's H-frame is the analogous asset: energy upgrades - gap, shims, dees, RF power - can stage around the same 757-lb iron for years. The platform reading is the editorial lesson drawn from ORNL's staged reuse of one magnet line (1.5 MeV, then 5 MeV, then proposed heavy ions); the quote itself carries the renaming.

Since this circuit depends upon the electrical characteristics of the resonant dee system, it cannot be designed until these characteristics are determined.

Howard (ed.), Electronuclear Research Division Semiannual, period ending 20 September 1953 — ORNL-1663 (1954) — p. 18

Editorial note, tabletop extrapolation: The template for the reference machine's LDMOS upgrade - freeze the amplifier and dee-resonator designs, but specify the matching/coupling network only after measuring the real dee system's f0, Q, and shunt impedance on the bench. Ordering the coupling parts first is the classic mistake this rule prevents.

The liner, dees, and dee-stem housing are being fabricated by an outside contractor. The faceplates, dee stems, ion source, target probe, and vacuum system were fabricated locally

Howard (ed.), Electronuclear Research Division Semiannual, period ending 20 March 1954 — ORNL-1670 (1954) — p. 20

Editorial note, tabletop extrapolation: The three-report arc remains this collection's cleanest outsourcing story: the contracted brazed, water-cooled vacuum parts were where the delays landed - one program's experience, and a fair prior. For a next machine: buy simple machining, keep leak-integrity parts in-house or design them repairable.

Cited in: The Vacuum Budget of a Cyclotron

This spacer moves the dees back from the center of the magnetic field so that the machine can be operated at approximately 1.5 Mev for test operation at very high proton currents.

Howard (ed.), Electronuclear Research Division Semiannual, period ending 20 March 1954 — ORNL-1670 (1954) — p. 20

Editorial note, tabletop extrapolation: Mirrors staged-gate logic - plan a low-energy high-current commissioning configuration as a mechanical state, not an improvisation, so beam-physics problems are separated from full-energy behavior. Reduced energy closes many reaction channels but not all: thresholdless capture (12C(p,gamma), 14N(p,gamma)) and light-element targets remain live, and very high current makes small cross sections and thermal loads consequential - so each commissioning state still gets its own reaction check, survey and beam-loss budget.

All other components of the present 44-in. cyclotron, oscillator, dee system, vacuum system, ion source, target-probe, and power supplies, would be utilized.

Howard (ed.), Electronuclear Research Division Semiannual, period ending 20 September 1954 — ORNL-1795 (1954) — p. 23

Editorial note, tabletop extrapolation: A strong argument for clean interfaces between a next machine's subsystems: ORNL could contemplate a new machine class for the price of iron and a tank because everything else was JUDGED reusable - the judgment is the quote's; the adaptation cost of the reuse is not on this card. Design interfaces so the same judgment could be true of your machine.

a large amount of existing equipment was adapted for use in the accelerator, and many design compromises were accepted. Consequently, this machine lacks the versatility and reliability which are essential ... which cannot readily be corrected: 1. The cyclotron is not and cannot be shielded ... [the dee stems] must enter the vacuum through bushing insulators. This limits the maximum dee-to-ground potential to about 40 kv ... 4. The magnetic field gap is only 6 in., less than half of what it should be to obtain the desired output.

Howard (ed.), Electronuclear Research Division Semiannual, period ending 20 March 1955 — ORNL-1884 (1955) — p. 20

Editorial note, tabletop extrapolation: The counterweight to thrift - surplus-equipment compromises in shielding provisions, magnet gap, and insulator ratings are the ones a finished machine cannot shed. When designing a next machine around salvaged parts, check each against this five-item list; anything on it deserves new hardware.

Being mostly below ground level, the room will be easy to shield. Placing the room at the basement floor level will make it convenient to transfer heavy equipment.

Howard (ed.), Electronuclear Research Division Semiannual, period ending 20 March 1955 — ORNL-1884 (1955) — p. 21

Editorial note, tabletop extrapolation: Directly relevant to the facility question for any MeV-class educational machine: below-grade siting was the study's shielding strategy, and siting beside existing utilities and controls was a cost line they weighed as seriously as the magnet. Earth shields in the directions it actually covers, by its actual thickness, density and moisture - it does not blanket-replace engineered shielding, and the uncovered directions, the roof, and every penetration still get the full design treatment (see the shielding deep dive).

Cited in: Choosing Your Machine · Shielding a Small Cyclotron

The major components have been assembled and vacuum-tested (see Fig. 5).

Howard (ed.), Electronuclear Research Division Semiannual, period ending 20 March 1955 — ORNL-1884 (1955) — p. 19

Editorial note, tabletop extrapolation: Schedule realism, one datapoint thick: a professional division with machine shops took about two years from revision concept to vacuum-tested assembly, with outsourced fabrication the long pole (dg-951). A home program's periods stretch and compress differently; the census's one-to-six-year first-beam spread is the wider base rate.

By relaxing the original requirements for extremely high field uniformity, a considerable simplification of the Browne-Buechner design was achieved in reducing the magnet yoke structure to a simple C-shape.

Alford, Bilaniuk & Hawrylak, Broad Range Spectrograph for Use with the Rochester 27-inch Cyclotron — NYO-9683 (1961) — p. 7

Editorial note, tabletop extrapolation: DIRECT and very relevant to a next machine - the whole report is a case study in not copying the flagship instrument (Browne-Buechner at MIT) but re-deriving requirements from the local physics program. Compact C-yokes, deferred correction hardware ("add spacers only if needed" - they never were), and unconventional yoke placement are all fair game once the real spec is known.

the information of Figs. 5 and 6 can be combined into a nomograph ... corresponding values of proton energy, lithium resonance frequency and image position on the focal surface

Alford, Bilaniuk & Hawrylak, Broad Range Spectrograph for Use with the Rochester 27-inch Cyclotron — NYO-9683 (1961) — p. 13

Editorial note, tabletop extrapolation: DIRECT for the teaching program: the 2026 equivalent is a small lookup app with nu*rho-vs-energy curves per probe nucleus and kinematics tables for the expected reactions (natural extensions of the sourced three-variable nomograph); run-time decisions need precomputed inverse tables, and students can build the nomograph itself as an exercise.

if proper safeguards are incorporated into the construction of the accelerator facility the cost of safety will be significantly lower then if such safeguards are superimposed upon already existing facilities.

Martin (ed.), Accelerator Radiation Protection — AD-755510 / USA-NLABS-TR-73-7, US Army Natick Laboratories (1972) — p. 17

Editorial note, tabletop extrapolation: Why a hazard analysis belongs at desk phase rather than after first beam: the enclosure, interlocks and monitoring get designed into the machine rather than left to whoever installs it.

Cited in: Choosing Your Machine

it may be necessary for the operations staff to act as the health physics staff as well. Though less then ideal, this condition will frequently be a "way of life". Under these conditions it is of paramount importance to define responsibilities and priorities.

Martin (ed.), Accelerator Radiation Protection — AD-755510 / USA-NLABS-TR-73-7, US Army Natick Laboratories (1972) — p. 19

Editorial note, tabletop extrapolation: A 1972 acknowledgement, with conditions, of the small-facility reality in which one person wears both the operator and radiation-safety hats. The conditions transfer to any teaching installation - the documentation names the RSO-equivalent role and its decision rights - and the arrangement itself must clear the jurisdiction's requirements: registered machines commonly require a named, qualified RSO (/legal/), which written role definitions support but do not replace.

alerted by the ORNL studies of observed beam loss in the ORIC cyclotron to try to avoid

Rainwater et al., The Columbia University Nevis Synchrocyclotron Major Modification — NEVIS-189 / R-774 / CU-295 (1971) — p. 4

Editorial note, tabletop extrapolation: Method transfers directly — a tune plot should carry resonance lines sourced from operating-experience literature, not just textbook theory; a weak-focusing tabletop crosses fewer lines but the audit habit is the point.

with all workers averaging below 100 mrad/week, and most below 25 mrad/week for the 10 weeks of this activity

Rainwater et al., The Columbia University Nevis Synchrocyclotron Major Modification — NEVIS-189 / R-774 / CU-295 (1971) — p. 4

Editorial note, tabletop extrapolation: Dose scale is irrelevant to a 150 keV proton machine, but the pattern — cooling time, planned sequence, measured-not-assumed exposure — is the template for any future activated-hardware work and for the plan's licensing narrative.

There is often a safety officer appointed. Many installations have safety review committees.

Ohnesorge & Butler, Recent Trends in Particle Accelerator Radiation Safety — CONF-741040-6, Oak Ridge National Laboratory (1974) — p. 3

Editorial note, tabletop extrapolation: For a one-person program the transfer is external review - the archive's cross-review protocol is exactly this committee function. For the planned educational-accelerator business, whether a named safety officer and a written program are REQUIRED is the jurisdiction's call (/legal/); the survey records the practice, and the practice is worth adopting either way.

the As Low As Practicable philosophy can be adopted and put into practice only where there is a firm commitment by management to do so

Ohnesorge & Butler, Recent Trends in Particle Accelerator Radiation Safety — CONF-741040-6, Oak Ridge National Laboratory (1974) — p. 3

Editorial note, tabletop extrapolation: The governing philosophy any licensing narrative must speak fluently - in its modern wording (ALARA), since the terms are not interchangeable in a regulatory context. For the home program it means shielding and interlock decisions justified as 'as low as reasonably achievable', not 'under the limit'.

Total Operating Time 831.3 ... 60.1 ... Outage Total 551.2 ... 39.9 ... Scheduled Operating Time 1382.5

Cyclotron Staff, Report of Cyclotron Operation 1 July – 31 December 1969 — NRL Memorandum Report 2103, Naval Research Laboratory (1970) — p. 33

Editorial note, tabletop extrapolation: A run log that records why each session ended, in fixed categories, turns anecdote into a failure Pareto within a year. The NRL 60/40 split is one professionally staffed machine's half-year - a sobering calibration, not a forecast: build the spare-time machine's own ledger and let it set expectations.

Beam Tuning 55.0 ... 4.0 ... Start Up and Shutdown 77.5 ... 5.6

Cyclotron Staff, Report of Cyclotron Operation 1 July – 31 December 1969 — NRL Memorandum Report 2103, Naval Research Laboratory (1970) — p. 33

Editorial note, tabletop extrapolation: Pump-down, filament conditioning, and field settling are largely per-session costs on a small machine; if your own log confirms that, batching experiments into fewer, longer sessions raises the beam-on fraction - measure the local session overhead first rather than assuming NRL's accounting transfers.

In most cases development is in parallel with operation of the cyclotron. However, major changes may require shut-down of the cyclotron for these modifications to be effected.

Cyclotron Staff, Report of Cyclotron Operation 1 July – 31 December 1969 — NRL Memorandum Report 2103, Naval Research Laboratory (1970) — p. 19

Editorial note, tabletop extrapolation: Grouping every open-the-chamber job (seal replacement, source work, new feedthroughs) into one planned vent-and-rebuild window costs one pump-down and one reconditioning instead of many - sound practice on its own logic, whatever NRL's exact schedule was.

the cyclotron was in operation 1680 hours, or about 18 hours per day. Three days were lost due to failure of the refrigerator for the cold-trap above the diffusion pumps. Another day was lost because of inadequate oil levels in the diffusion pumps.

Harvard University Cyclotron Laboratory, Quarterly Progress Report, 1 June – 31 August 1964 — p. 1

Editorial note, tabletop extrapolation: An upper anchor for what sustained cyclotron utilization can look like - useful against the NRL 60% figure only as a rough contrast, since the two reports account time differently (Harvard reports operating hours and lost days; NRL a full scheduled-time ledger). Note both of Harvard's losses were vacuum-auxiliary failures - cold-trap refrigeration and pump oil - not accelerator physics.

A scheduled shutdown of about one week was required to install apparatus for pulsed deflection of the internal beam.

Harvard University Cyclotron Laboratory, Quarterly Progress Report, 1 June – 31 August 1964 — p. 1

Editorial note, tabletop extrapolation: Conditional batching guidance, not a demonstrated result: when several tasks require opening the same vacuum boundary, combining them into one planned shutdown saves repeated venting, pump-down, leak-checking and conditioning cycles - the same pattern as NRL's engineering shutdown, at a smaller scale.

both the first cost and the power cost of a magnet increase almost proportionately with an increase in beam radius.

Wakerling & Guthrie (eds.), Magnets and Magnetic Measuring Techniques — TID-5215, Radiation Laboratory, University of California (1949) — p. 24

Editorial note, tabletop extrapolation: Useful scaling honesty for any pole-diameter trade study — going from 8 to 13 in. poles at fixed final energy is a near-linear cost move, not a quadratic one, so long as the field comes down as the radius goes up.

Cited in: Choosing Your Machine

the excellent results obtained in testing track 1 showed that a dimensional check of the shim positions was entirely adequate.

Wakerling & Guthrie (eds.), Magnets and Magnetic Measuring Techniques — TID-5215, Radiation Laboratory, University of California (1949) — p. 191

Editorial note, tabletop extrapolation: The economic payoff of validation, with its boundary drawn correctly: dimensional-only acceptance covers exact replicas made under the same materials, tooling and process - a CHANGED shim geometry is a new magnetic configuration and gets its own field map. In one-off tabletop practice, that means the caliper substitutes for the gaussmeter only when re-making the same part, never when revising it; keep periodic magnetic audits regardless.

We have had available for our use a complete set of the Berkeley plans which was kindly placed at our disposal by Professor E. O. Lawrence.

The University of Washington 60-Inch Cyclotron: Progress and Status Report of Design and Construction — AECU-1951, University of Washington (1951) — p. 6

Editorial note, tabletop extrapolation: The strategy transfers directly: for any new machine, start from the closest documented working design - this corpus and the builds census exist to make that possible - and spend novelty only where the precedent is silent.

Cited in: Choosing Your Machine

On the basis of cost it was decided to omit this refinement.

The University of Washington 60-Inch Cyclotron: Progress and Status Report of Design and Construction — AECU-1951, University of Washington (1951) — p. 90

Editorial note, tabletop extrapolation: The decision pattern - name the deleted protection, name what stands in for it, keep a commissioning-only resistor in the drawer - is reusable as an engineered, recorded risk acceptance, not a license: verify the stand-ins actually bound the fault energy for YOUR stored energy and clearing time (a 6-cycle breaker passes ~0.1 s of fault current), and re-examine the acceptance at each upgrade. Contrast ucrl-9435, where the 88-inch - with 20x the stored energy - bought the full hard-tube-modulator protection instead. Scale decides.

Machining work will begin after the oscillator is operating and an internal beam produced.

The University of Washington 60-Inch Cyclotron: Progress and Status Report of Design and Construction — AECU-1951, University of Washington (1951) — p. 116

Editorial note, tabletop extrapolation: The commissioning-order lesson as an explicit 1951 schedule decision: internal beam first, extraction hardware behind it. A sensible default for a next machine - the probe and its lock as first-beam hardware, extraction machining held until the internal beam teaches you the real orbit - a default, not a law.

Total expenditures to date from all sources, excluding University of Washington overhead and staff salaries, has been $642,000.

The University of Washington 60-Inch Cyclotron: Progress and Status Report of Design and Construction — AECU-1951, University of Washington (1951) — p. 124

Editorial note, tabletop extrapolation: A historical cost-accounting example that corroborates the plan's assumption from the construction side: facility/infrastructure rivalled machine materials HERE, and reported totals understate true cost by the labor the institution absorbed - for an educational-accelerator business, price materials PLUS the labor a customer cannot donate. One project's ratio is context, not a law.

Bevor man an den Nachbau eines Zyklotrons geht, muss man sich darüber im Klaren sein, was man benötigt. ... Bei den fünf Teilsystemen handelt es sich im einzelnen um das Magnet-System, das das Führungsfeld liefert, das Beschleunigungs-System, das für die Hochspannung sorgt, das Ionen-System, verantwortlich für die Produktion der Ionen, das Vakuum-System, das das erforderliche Vakuum zur Verfügung stellt, und schließlich das Detektor-System, das die beschleunigten Teilchen registriert. ... Die Vorgaben in den grünen Kreisen sind zum einen gerätespezifische Größen. Dazu gehören: der Radius der Magnetpole rp und der maximale Bahnradius ... das Nenn-Saugvermögen SN des Pumpstands [tr.: before building a cyclotron one must be clear what is needed; the five subsystems are the magnet system supplying the guide field, the acceleration system providing the high voltage, the ion system producing the ions, the vacuum system, and the detector system registering the accelerated particles; the givens in the green circles are device-specific quantities - the pole radius, the maximum orbit radius, the pump stand's nominal pumping speed - the calculated quantities in blue circles]

Prechtl & Wolf, Das Lehr-Zyklotron COLUMBUS — Mit einem Teilchenbeschleuniger Physik und Technik erleben, Springer (2020) — p. 27-29

Editorial note, tabletop extrapolation: A small machine has few free parameters; listing which are fixed by hardware (pole radius, pump) and which are design choices (B, gap, U0, species) keeps the sizing chain consistent and exposes circular dependencies early.

Mit einer Beschleunigungsspannung der Frequenz von 5,64 MHz werden Protonen in einem Magnetfeld von B0 = 370 mT resonant beschleunigt. Unter diesen Bedingungen wäre für die H2+-Ionen die Umlaufdauer doppelt so groß; sie würden dann den ersten Halbkreis im Dee nicht phasenrichtig zum elektr. Wechselfeld verlassen. ... Als Frequenz der Beschleunigungsspannung wählt man 2,82 MHz mit 1000 V Amplitude [tr.: at 5.64 MHz accelerating frequency, protons are resonantly accelerated in a 370 mT field; under these conditions the H2+ orbital period would be twice as long and they would leave the first semicircle out of phase; for the accelerating voltage one chooses 2.82 MHz with 1000 V amplitude]

Prechtl & Wolf, Das Lehr-Zyklotron COLUMBUS — Mit einem Teilchenbeschleuniger Physik und Technik erleben, Springer (2020) — p. 37-39, 70-71

Editorial note, tabletop extrapolation: The design-vs-operated distinction this card exists for: conference-paper numbers are usually design values - cite measured operating points with their species and date, and never let one row imply a field-frequency pair serves two species at once.

Sicher hätte sich das Projekt nicht gelohnt, wenn es nach dem erfolgreichen Abschluss im Jahre 2014 beendet worden wäre [tr.: the project would not have been worth it had it ended in 2014]

Prechtl & Wolf, Das Lehr-Zyklotron COLUMBUS — Mit einem Teilchenbeschleuniger Physik und Technik erleben, Springer (2020) — p. 75-76

Editorial note, tabletop extrapolation: The listed follow-on improvements (magnet stand, acceleration simulation, probe translator, mechanical model) are the kind of second-year items a small-machine program should schedule rather than improvise - as this case study's pattern, adapted to local aims, not a universal checklist.

Trotzdem konnten wir nur bedingt auf bereits gemachte Erfahrungen zurückgreifen. Zu unterschiedlich waren die Voraussetzungen [tr.: prior experience was only partly usable; conditions were too different]

Prechtl & Wolf, Das Lehr-Zyklotron COLUMBUS — Mit einem Teilchenbeschleuniger Physik und Technik erleben, Springer (2020) — p. 8

Editorial note, tabletop extrapolation: The transferable layer across amateur machines is the METHOD - dependency diagram, rigidity sizing, vacuum chain, species-by-q/m - not the numbers: copy the method, recompute every quantity for your own boundary conditions. (Which differences blocked reuse here isn't itemized in the quote; the lesson survives without the itemization.)

although a permanent magnet was considered for the Cyclotrino, it used an electromagnet because the field could be tuned

Cressman, The Design and Construction of a Small Cyclotron — Houghton College thesis (2006) — p. 16

Editorial note, tabletop extrapolation: Field tunability is a resonance-hunting knob a permanent-magnet machine gives up - which it can buy back through RF adjustment, measured-field frequency selection, shims or trim coils; the precedent documents the convenience of the tunable field, not a prohibition on permanent magnets.

one a 22.9 cm diameter prototype and the other was the final 30.5 cm diameter machine, finished in 2001. The prototype operated at 0.889 T, using a dee and dummy dee design. The prototype chamber was constructed for use in the 30.5 cm cyclotron that was the ultimate goal of this project, and so was much larger than required. It was stainless steel, as were the ports and flanges. ... The larger machine used a 30.5 cm pole face electromagnet that operated in excess of 1.0 T, with the same chamber as the 22.9 cm cyclotron but with a different ion source.

Cressman, The Design and Construction of a Small Cyclotron — Houghton College thesis (2006) — p. 17

Editorial note, tabletop extrapolation: Oversizing the first chamber lets the highest-labor component survive the upgrade - a trade, not a law: a larger chamber costs pumping speed, gap (if it sits in the magnet) and money now against rework later; the same survey documents the opposite staging too, so decide from where the rework hurts most on YOUR roadmap.

Cited in: Cyclotron Vacuum Chamber Design and Sealing

As the ion source was considered experimental and a weak design aspect, it was made to be completely removable.

Cressman, The Design and Construction of a Small Cyclotron — Houghton College thesis (2006) — p. 18

Editorial note, tabletop extrapolation: Design for swap-out on the least-trusted subsystem - mount whatever you expect to iterate for convenient replacement. Ion sources are a common iteration target in this literature (COLUMBUS's Penning investigation, Rutgers' source change between machines), though no count across the survey backs a strongest-claim ranking.

The immediate objective is to accelerate Helium nuclei to test the machine, and the ultimate is to accelerate deuterons to produce neutrons ... The expected energy for deuterons is 0.15 MeV, and 0.08 MeV for Helium nuclei. ... the maximum energy for singly ionized helium is 77.2 keV. For doubly ionized helium, the frequency in the same magnetic field is 8.63 MHz ... and the maximum energy is 309 [keV]

Cressman, The Design and Construction of a Small Cyclotron — Houghton College thesis (2006) — p. 2

Editorial note, tabletop extrapolation: Debugging resonance, focusing and diagnostics on helium defers the deuteron-specific neutron/activation source term - NOT all radiological consequences: RF/HV dark current makes bremsstrahlung with any gas, and He2+ is an alpha that can drive exothermic reactions on light contaminants (Be-9, C-13). Survey from first powered operation; the staging defers the big term, not the survey.

Longer range plans include building a larger vacuum chamber and electrodes

Cressman, The Design and Construction of a Small Cyclotron — Houghton College thesis (2006) — p. 48

Editorial note, tabletop extrapolation: Starting with an undersized chamber inside a full-size magnet is the documented counter-strategy to Rutgers' build-the-final-chamber-first (dg-1451) - the stated plan here being a larger chamber and electrodes later. Faster first beam and deferred precision work are the plausible payoffs to EVALUATE, not documented outcomes; either staging is defensible depending on where rework hurts.

Cited in: Cyclotron Vacuum Chamber Design and Sealing

After the FZ Juelich provided a magnet, VACOM, a company for vacuum components, sponsored a suitable vacuum chamber ... the cyclotron COLUMBUS began in 2012. ... The first beam was registered in April 2014 (see Fig. 2), which was followed by the first workshop with students in autumn of the same year. ... The COLUMBUS project, started in 2012, has developed very positively in the last 10 years.

Wolf & Prechtl, COLUMBUS — A Small Cyclotron for School and Teaching Purposes — THPO001, Proceedings of Cyclotrons2022 (2022) — p. 1

Editorial note, tabletop extrapolation: A realistic schedule anchor for the plan's teaching-machine ambitions: two years start-to-beam WITH a donated magnet and sponsored chamber - the in-kind support is part of the datum. And the methodological point stands: a conference paper's year dates the claim; prefer the builders' own retrospective dates when reconstructing a machine's history.

or investigate a Penning ion source with the aim of using it for the installation in the accelerator.

Wolf & Prechtl, COLUMBUS — A Small Cyclotron for School and Teaching Purposes — THPO001, Proceedings of Cyclotrons2022 (2022) — p. 2

Editorial note, tabletop extrapolation: A filament source reached first beam here and a candidate Penning source is being investigated as a student project - the sensible pattern being to characterize any replacement source off-machine, then verify its mechanical, vacuum, electrical, gas-feed and central-region interfaces before installation; a source swap touches more of the machine than the source (recommendation, not the paper's documented method).

The cyclotron was continuously improved and expanded with the involvement of pupils and students.

Wolf & Prechtl, COLUMBUS — A Small Cyclotron for School and Teaching Purposes — THPO001, Proceedings of Cyclotrons2022 (2022) — p. 1

Editorial note, tabletop extrapolation: An educational machine CAN make learner projects its upgrade workforce when they are scoped as real subsystem work - a Faraday-cup translator or a field map is simultaneously curriculum and infrastructure; whether that is the fastest improvement route is a program-design judgment, not this paper's measurement.

In order to build such a small cyclotron one has to meet two conditions: Vacuum, magnetic field, frequency etc. must be so low that one can use standard components as far as possible, otherwise the costs will go to infinity; The final energy of the cyclotron must be small enough so that no harmful radiation can arise, so that the students can do experiments with the cyclotron. Table 1 shows the technical data of COLUMBUS. One can easily recognize that COLUMBUS meets all the conditions mentioned above.

Wolf, Frank & Held, COLUMBUS — A Small Cyclotron for School and Teaching Purposes — WE1PB03, Proceedings of Cyclotrons2013 (2013) — p. 1

Editorial note, tabletop extrapolation: A hobby-scale build benefits from the same requirements discipline; writing the cost condition and the radiation condition down first turns every later component choice into a check against them. The radiation condition itself needs its own verification, not just an energy number: whether 'no harmful radiation can arise' at a given operating point is the paper's claim for its machine, and X-rays begin when high voltage or RF is energized, before any beam.

Table 1: Technical Data — Diameter of the Dees 140 mm (5.5 in); Flux-density of the magnetic field 0.38 T; Vacuum in the chamber 10-5 mbar; dto with H2 10-4 mbar; Cyclotron frequency 5.63 MHz; Number of revolutions 6-8; Voltage between the dees 2.0 -3.0 kV; Final energy 24 - 48 keV … The expected final energies of the protons are 24 - 48 keV after 6 - 8 revolutions. These energies don't produce any radiation outside the chamber.

Wolf, Frank & Held, COLUMBUS — A Small Cyclotron for School and Teaching Purposes — WE1PB03, Proceedings of Cyclotrons2013 (2013) — p. 1

Editorial note, tabletop extrapolation: A conference paper's date fixes the claim, not the beam; when reusing published small-cyclotron parameters, check whether the paper predates first beam and label such values as design predictions rather than demonstrated performance.

At the very beginning there were two big problems: How to get a magnet for the homogenous field and How to get a suitable vacuum-chamber. The first problem was solved by the Research Institute of Jülich. Prof. Dr. Maier and his team donated a Bruker BE-15. … The second problem was solved by VACOM, a company specialized in vacuum-components. VACOM built the vacuum-chamber, i.e. Fig. 1, for us free of charge.

Wolf, Frank & Held, COLUMBUS — A Small Cyclotron for School and Teaching Purposes — WE1PB03, Proceedings of Cyclotrons2013 (2013) — p. 1

Editorial note, tabletop extrapolation: For an educational build, soliciting institutional donations for the few components a home or school shop cannot make is a documented alternative to surplus-market hunting.

Cited in: Cyclotron Vacuum Chamber Design and Sealing

The protons for our cyclotron are produced in the ion source which was built after the pattern of Tim Koeth [1], which he used first in his cyclotron. … A specific design of the ion source was required due to the cyclotron's small size and the low number of revolutions … It was designed for adjusting the position of the ion source itself and the proton's angel of emission. … [1] Tim Koeth, "The Rutgers 12-Inch Cyclotron Ion Source Studies Part I"

Frank, Wolf & Held, COLUMBUS — A Simple Ion Source — WEPPT021, Proceedings of Cyclotrons2013 (2013) — p. 1, 2

Editorial note, tabletop extrapolation: A documented precedent for reusing a published hobby-machine source design: here the ionization geometry was adopted whole and the adaptation effort spent on mounting and adjustability.

Especially for single production and prototypes, 3D printing technology can be of considerable benefit. This is particularly due to the freedom in geometry and the possibility of function integration, such as the realization of a surface heating system.

Wolf, Beck, Franz & Neumaier, 3D Printing for High Vacuum Applications — THC04, Proceedings of Cyclotrons2019 (2019) — p. 4

Editorial note, tabletop extrapolation: A one-off machine is exactly the single-production case; a sound screening default is to consider printing where a part is unique and geometrically complex and to price catalog, machined, welded and printed options case by case.

The study of the beam height was carried out before the magnetic field was adequately regulated, and the results are only qualitative ... The experimental measurement of the width of the resonance curve shown in Fig. 2 was the most accurate part of the program. The curves were reproducible, and the maximum error in their widths amounted to only a few per cent.

Burns, Experimental Program with the Iowa State University Undergraduate 1.5 Mev Cyclotron — Proceedings of the Iowa Academy of Science 68(1), 483–491 (1961) — p. 6

Editorial note, tabletop extrapolation: Editorial note, tabletop extrapolation: field-supply regulation bounds every beam measurement made through a field sweep — verify that field stability is small against the required measurement uncertainty before quantitative field-sensitive scans. Data taken before the supply is stabilized will likely have to be repeated.

The experimental program on the Iowa State University undergraduate 1.5 Mev cyclotron is divided between cyclotron technology experiments and nuclear experiments. Beam technology work has been done in the determination of the shape of the resonance curve as a function of the magnetic field strength and radius, the determination of the tune-down at various radii, and the measurement of the vertical excursion of the protons (beam height). The experimental measurements have been compared to the theoretical calculations made for the ISU cyclotron by A. H. Mueller (1). The nuclear physics experiments are limited to the lightest elements due to the low energy of the machine. Comprehensive experiments have been performed using lithium and carbon as the target material ... [footnote:] This work was made possible in part by grants from the National Science Foundation Undergraduate Research Participation Program.

Burns, Experimental Program with the Iowa State University Undergraduate 1.5 Mev Cyclotron — Proceedings of the Iowa Academy of Science 68(1), 483–491 (1961) — p. 2

Editorial note, tabletop extrapolation: Editorial note, tabletop extrapolation: a low-energy machine supports a real two-track curriculum — the accelerator itself as measurement subject (tuning curves, field studies, beam optics) plus light-element nuclear physics. The machine-as-experiment track begins as soon as beam circulates; the nuclear track needs its own justification per experiment — reaction energetics, yield at the available current, detection capability, and radiation controls.

Actually, several important phenomena have been neglected in these calculations. For one, phase grouping, as described by Cohen (6), has not been considered ... Also, the assumption that all protons with negative initial phases would be lost from the beam and that no protons with positive initial phase would be lost from the beam because of defocusing is not entirely justified ... The intensity curves shown in Figure 4 are expected to give a correct qualitative description of the beam in the cyclotron and to provide a rough quantitative description

Mueller, Proton Orbit Calculations for the Iowa State University Cyclotron — Proceedings of the Iowa Academy of Science 68(1), 492–501 (1961) — p. 8, 9

Editorial note, tabletop extrapolation: Editorial note, tabletop extrapolation: declaring a model's omissions up front turns experiment-theory disagreement into information — each discrepancy gets a candidate attribution to a listed omission instead of eroding trust in the whole calculation. These are proposed explanations to test (add effects one at a time, compare residuals), not validated causes. This is the working pattern for pairing simple orbit models with commissioning data.

The IUAC personnel will witness and participate in the complete process of fabrication, testing and field mapping of the electromagnetic system at the vendors site ... The final acceptance of the system is defined as successful supply, installation and acceptance tests at IUAC to substantiate compliance with the specification ... All testing equipment shall be arranged by the vendor at no extra cost ... After shipment to IUAC, the magnet will be tested by IUAC personnel with full power to check the magnetic field is maintained as per design, before releasing the payment.

IUAC, e-Tender 09/GOR/2024–25 — H-Dipole Water-Cooled DC Electromagnet for the Table-Top Cyclotron: Engineering Specification and Acceptance Tests (2024) — p. 13, 15, 26

Editorial note, tabletop extrapolation: Editorial note, tabletop extrapolation: a clean template for outsourcing a magnet build while keeping engineering control — approve materials and drawings first (the steel goes through written approval before procurement, dg-1612), witness the factory tests, repeat the field checks at full power after shipping, and only then accept and pay. Anyone commissioning a magnet from a job shop can scale down the same factory-then-site structure.

[Facility licensing status table — Facility / Status / License valid till:] Table Top Cyclotron — Initiated — NA (listed alongside Running facilities such as the Pelletron-linac, and the HCI facility with design construction approval) ... Civil work for setting up of the cyclotron development laboratory and storage racks.

IUAC, Annual Report 2024–25, Chapter 3 — Research Support Facilities (table-top cyclotron RF system) — p. 23, 37

Editorial note, tabletop extrapolation: Editorial note, tabletop extrapolation: method observation, not a dose rule — the machine sits in the regulator-facing facility-status table from project initiation, so authorization proceeds in parallel with construction rather than gating it at the end. What 'Initiated' commits either party to, the table does not define; the transferable habit is the early appearance itself. Small-accelerator builders in any jurisdiction can copy the early-engagement pattern.