Every headline number regenerates from a named script and archived data under a fixed random seed; requirement-class assumptions and open risks are carried openly rather than absorbed into a single optimum. Each paper below has its own reading edition (the editorial), the manuscript PDF, its published Zenodo DOI, and its data-and-code package.
The complete volume
The Kronos 2026 Publication — Complete Volume
All studies in one bound volume: the compact fusion isotope-and-energy platform, front to back — breeder, generator, magnets, direct energy conversion, AI/quantum control and the full de-risking programme — with the shared methodology, notation and reproducibility manifest that ties them together.
Register
the hub · Paper 1.0
Paper 1.0
P. I. Ford · Kronos Fusion Energy
The Physics De-Risking Register is the public, gate-by-gate evidence layer for the Kronos compact spherical-tokamak breeder and its D–3He tandem-mirror burners: every headline anchor carries a gate serial and is independently re-run and stamped. (Editorial file to be supplied by the founder.) Related: Paper page · De-risking register · 3D model · Learn more about Kronos Part of the 2026 Kronos publication series; independently…
Phase 1 — Foundational
6 papersThe foundational studies: the breeder, the two burners, the magnets, direct energy conversion, and the control stack.
Paper 1.1
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Fusion breeders have historically foundered on two coupled obstacles: net electricity forces a large plasma and a large blanket, and a self-sufficient closed fuel cycle at power-plant scale implies a dangerous standing tritium inventory. Both are consequences of demanding electricity from a device whose neutrons are physically its most valuable output. We present the integrated physics of Hyperion, a compact negative-triangularity…
Paper 1.2a
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Aegis is the forward-base configuration of the Kronos deuterium–helium-3 tandem-mirror burner: a fixed, hardened, grid-independent installation that turns an aneutronic-dominated fusion source into firm electrical power for a defence site without a fuel-convoy tail. This paper is a comprehensive, review-article treatment of the integrated physics case for that machine, and it separates, throughout, what is robust from what is…
Paper 1.2b
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The load that a hyperscale artificial-intelligence campus imposes on the grid is native direct current, growing faster than transmission can be built, and increasingly sited where interconnection queues are measured in years. We present MetroVolt, a data-center power plant built on the Kronos deuterium–helium-3 (D–^3He) tandem-mirror burner, whose direct energy converter (DEC) delivers high-voltage direct current natively—the same…
Paper 1.3
P. I. Ford, R. J. Weggel, C. Weggel · Kronos Fusion Energy
The enabling technology of compact fusion is the high-field rare-earth barium copper oxide (REBCO) magnet, and the binding engineering limit of such a magnet is not the coated conductor's critical current but the irreversible strain the winding may carry under Lorentz load. We present an extended design-and-analysis study of the REBCO superconductor basis shared by the two dissimilar machines of the Kronos platform: the centrepost…
Paper 1.4
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A deuterium–helium-3 (D–^3He) tandem-mirror burner puts most of its fusion power into charged particles, so it admits an option a tokamak does not: recover the exhaust electrostatically, as electricity, without a thermal cycle or a turbine on the direct channel. This paper is the flagship, review-length treatment of that option for the Kronos burner (engineering gain Q_E=1.318 at P_ fus=4298.5 MW, neutron fraction f_n=5.44 %, plug…
Paper 1.5
P. I. Ford · Kronos Fusion Energy
A nuclear-regulated fusion generator must be controlled across ten orders of magnitude in time — microsecond magnet protection through month-scale fuel logistics — and every automated actuation must be bounded, auditable, and reproducible. We present the umbrella account of the Kronos computational and control programme, developed to review-article depth, and we hold its three technology-readiness tiers strictly apart.…
Phase 2 — Companion
108 papersCompanion studies that pin each binding gate individually — from the consumable centrepost and the blanket breeding ladder to disruptions, the helium-3 cycle, licensing, controls, quantum methods and buildability.
Paper 2.1
P. I. Ford, R. J. Weggel, C. Weggel · Kronos Fusion Energy
Compact fusion is usually presented as a single machine chasing net electricity. Kronos is instead a platform of two machines with one physics record: a compact negative-triangularity spherical-tokamak breeder (Hyperion) that makes strategic materials, and a deuterium–helium-3 tandem-mirror burner (deployed as Aegis and MetroVolt) that makes power. We give a single, self-consistent formal treatment of the platform. The breeder…
Paper 2.2
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Fuel choice is the most consequential and the most emotionally contested decision in a fusion program: the pull toward the aneutronic ideal routinely overrides the reaction physics. We grade the four candidate fuels — deuterium–tritium (D–T), deuterium–deuterium (D–D), deuterium–helium-3 (D–^3He), and proton–boron-11 (p–^11B) — on one quantitative ruler, deriving each axis from first principles rather than asserting it. Using the…
Paper 2.3
P. I. Ford, R. J. Weggel, C. Weggel · Kronos Fusion Energy
A tritium breeder is, before it is anything else, a bright and steady source of 14 MeV neutrons, and that source has value beyond breeding. We formalise the isotope-production and materials-qualification missions of the compact spherical-tokamak breeder (Hyperion) at its frozen operating point — fusion power P_fus=85.04 MW, gain Q=3.076, plasma current I_p=9.66 MA, negative triangularity δ=-0.30 — which sustains a whole-device…
Paper 2.4
P. I. Ford · Kronos Fusion Energy
The confinement case for a compact spherical-tokamak breeder rests on a single physics question: does negative triangularity (NT) suppress the drift-wave turbulence that would otherwise cap the core pressure below the operating point? We answer it with first-principles nonlinear gyrokinetics at the frozen Hyperion design point (δ=-0.30, B_0=8 T, I_p=9.66 MA, R_0=1.20 m, aspect ratio A=2.5, κ=2.0, gain Q=3.076 at P_ fus=85.04 MW),…
Paper 2.5
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The bootstrap current is a load-bearing number for a compact breeder: it fixes how much of the 9.66 MA plasma current is self-driven, and therefore how much external current drive the machine must supply for solenoid-free steady state. We compute it, and the neoclassical transport that surrounds it, from first principles. A drift-kinetic solve with the GACODE code NEO — the full linearized Fokker–Planck collision operator, kinetic…
Paper 2.6
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Negative triangularity turns the plasma edge from the power-handling liability it is in a conventional tokamak into an engineering asset. At the Hyperion breeder's frozen operating point (δ=-0.30, I_p=9.66, Q=3.076, P_ fus=85.04, B_0=8, κ=2.0, =1.20, aspect ratio A=2.5), the edge is ELM-free by construction: the peeling–ballooning drive of an H-mode pedestal is never accessed, so the transient edge-localised-mode heat pulse that…
Paper 2.7
P. I. Ford · Kronos Fusion Energy
A fusion design point is physical only if it corresponds to a self-consistent free-boundary equilibrium that is stable to the fast ideal-magnetohydrodynamic (MHD) modes. We construct the equilibrium of the frozen compact negative-triangularity spherical-tokamak (ST) breeder and test its ideal stability on a reproducible, GPU-accelerated computational chain. A free-boundary Grad–Shafranov solution reproduces the design point…
Paper 2.8
P. I. Ford · Kronos Fusion Energy
Elongation buys confinement in a compact machine, and it is not optional: the Hyperion spherical-tokamak breeder holds I_p=9.66 at elongation κ=2.0 with negative triangularity δ=-0.30, aspect ratio A=2.5 and major radius =1.20. The price of that elongation is a passive axisymmetric vertical instability, and in a spherical tokamak the instability is fast. We pose the vertical-control problem formally, from the massless…
Paper 2.9
P. I. Ford · Kronos Fusion Energy
The disruption response is the credibility gap a compact, high-current spherical-tokamak (ST) programme is expected to answer, because such a machine stores a large magnetic and thermal energy in a small volume and releases it fast. We formalise the disruption, runaway-electron (RE), and electromagnetic-load problem for the frozen Hyperion breeder design point (=9.66 MA, =1.20 m, aspect ratio A=2.5, elongation κ=2.0, triangularity…
Paper 2.10
P. I. Ford · Kronos Fusion Energy
Fusion-born alpha particles must remain confined long enough to deposit their 3.5 of birth energy in the plasma, and their eventual losses must not concentrate as a localized load on the first wall. In a compact, high-current spherical tokamak (ST) neither requirement can be assumed: at a minor radius of only a=0.48 the fast-alpha banana width reaches 16 and the near-axis potato width 23, so a naive large-orbit shell estimate…
Paper 2.11
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A compact breeder that runs continuously has no inductive transformer to renew its plasma current: the full current must be held by the self-generated neoclassical bootstrap current plus external non-inductive drive, and the power that drive consumes is a real, named charge against the platform. We formalise and close the steady-state current balance for the Hyperion breeder at its frozen operating point (I_p=9.66, Q=3.076, P_…
Paper 2.12
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A spherical tokamak (ST) has almost no inboard room for a central solenoid, so it cannot induce and ramp its plasma current the way a conventional tokamak does; startup is therefore a defining physics and engineering constraint rather than a solved preliminary. We formalise and quantify a solenoid-free startup and ramp path for the Kronos Hyperion breeder (design point plasma current I_p=9.66, fusion gain Q=3.076, P_ fus=85.04,…
Paper 2.13
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A negative-triangularity spherical-tokamak breeder that operates near its no-wall stability limit is not held there passively: toroidal rotation, sheared E× B flow and the correction of residual error fields are the active layer that keeps a quiet core quiet and keeps a rotating plasma from braking into a locked mode. We formulate this layer from first principles for the Kronos Hyperion breeder at its frozen design point (I_p=9.66…
Paper 2.14
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A fusion power plant lives inside a bounded operating window, and the density limit is one of its walls. We pose the operating-window boundary of the Hyperion breeder — a compact negative-triangularity spherical tokamak (I_p=9.66 MA, =1.20 m, aspect ratio A=2.5, minor radius a=0.48 m, elongation κ=2.0, triangularity δ=-0.30, B_0=8 T) — as a formal feasibility problem and map its density axis. From the geometry the Greenwald density…
Paper 2.15
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The transient heat pulse from a Type-I edge-localized mode (ELM) is among the most demanding loads a fusion first wall must survive, and much of the conventional tokamak-reactor programme spends control authority — resonant magnetic perturbation coils, pellet pacing — to mitigate it. The Hyperion breeder avoids the load structurally. We formulate the edge-stability problem for the frozen negative-triangularity (δ=-0.30) operating…
Paper 2.16
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The inboard centrepost of a compact spherical-tokamak (ST) breeder sits closest to the 14 MeV source and is the machine's dominant lifetime risk: at useful breeding coverage the high-temperature REBCO conductor reaches its irradiation limit in a small fraction of a full-power year (fpy). We treat the centrepost as a consumable, scheduled-replacement cartridge and quantify the architecture through four coupled analyses on the frozen…
Paper 2.17
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The high-field REBCO magnet of a compact spherical-tokamak breeder is usually de-risked on field and stress; its survival in a neutron environment is a separate materials question, and the answer changes the conductor specification. The Kronos Hyperion centrepost sees a peak field of 16.84 T and a fast-neutron fluence budget capped at a frozen 3.9×10^22 n m^-2, while its physically distinct D–^3He tandem-mirror burner plug operates…
Paper 2.18
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The consumable centrepost of the Hyperion breeder carries the machine's peak field of 16.84 T inside its harshest neutron environment, so the irradiation lifetime of the centrepost REBCO conductor—not stress and not quench—sets the cadence at which the plant is opened and, through it, the fraction of the calendar available for power production. We pose the lifetime question as a coupled multiscale problem and solve it from first…
Paper 2.19
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The unsolved protection problem of high-temperature-superconductor (HTS) fusion magnets is that no-insulation (NI) REBCO windings quench too slowly for terminal-voltage detection to act before the local hot spot reaches a damaging temperature: the normal zone propagates at millimetres per second, so the resistive voltage integrated along it stays small while the deposited energy density climbs. We formalise and evaluate a…
Paper 2.20
P. I. Ford, R. J. Weggel, C. Weggel · Kronos Fusion Energy
The poloidal-field (PF) coils are what hold a strongly shaped, strongly elongated plasma in place: they must pull the outboard boundary inward to negative triangularity, sustain a doubling elongation against its own ideal vertical instability, and set the divertor null, while the toroidal-field magnet does its own, entirely separate job. We pose the coil-current problem for a compact negative-triangularity spherical-tokamak breeder…
Paper 2.21
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The pacing subsystem of the Kronos D–^3He tandem-mirror burner is the high-field plug coil that electrostatically confines the central-cell ions, and this paper qualifies it as a buildable no-insulation (NI) REBCO magnet at its canonical peak field of 26.49 T. We pose the qualification as three coupled engineering problems — can the structure carry the magnetic load, can the conductor survive its own hoop stress, and can a quench be…
Paper 2.22
P. I. Ford · Kronos Fusion Energy
The vacuum vessel and its support carry the entire electromagnetic, thermal and inertial load path of a compact spherical-tokamak breeder into the ground, and in a high-power-density device the impulsive disruption load, not the steady field or the seismic base excitation, sets the design. We formalise the vessel-and-support structural-mechanics problem for the Hyperion breeder (design point I_p=9.66, Q=3.076, P_ fus=85.04, negative…
Paper 2.23
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The cold-mass thermal budget decides whether a compact spherical tokamak can be built at all, because the toroidal-field current must pass through the tightest radius in the machine, where current density and neutron flux are simultaneously highest. We report the cryogenic case for the Hyperion breeder (design point I_p=9.66, Q=3.076, P_ fus=85.04, negative triangularity δ=-0.30, B_0=8, elongation κ=2.0, major radius =1.20, aspect…
Paper 2.24
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A deuterium–tritium plant that does not breed its own tritium is a consumer of a scarce, decaying, essentially unbuyable fuel; a plant that breeds a surplus is the seed of a supply chain. The distinction is set by a single neutron-economy quantity—the net tritium breeding ratio (TBR)—and, in a compact spherical tokamak (ST), that quantity is capped by the small inboard coverage the centrepost permits. We treat the blanket TBR of the…
Paper 2.25
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Tritium self-sufficiency must survive the geometry a machine is actually built to, not the idealised radial shell that sets the physics target. We transport 14 MeV neutrons directly on the as-drawn engineering CAD of the Hyperion compact spherical-tokamak breeder (frozen operating point Q=3.076, P_ fus=85.04 MW, I_p=9.66 MA, negative triangularity δ=-0.30, B_0=8 T, elongation κ=2.0, major radius =1.20 m, aspect ratio A=2.5) through…
Paper 2.26
P. I. Ford · Kronos Fusion Energy
The inboard centrepost is the defining vulnerability of a normal-conductor spherical tokamak: it sits closest to the 14.06 fusion source and cannot be thickly shielded without growing the machine or displacing the breeding blanket. We do not argue this away; we quantify it and design for it. We solve the steady linear Boltzmann transport equation for the Hyperion breeder (=1.20, aspect ratio A=2.5, B_0=8, I_p=9.66, P_ fus=85.04,…
Paper 2.27
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A tritium breeding ratio (TBR) is only as trustworthy as the cross-sections that produced it, and a design that quotes a TBR without an error bar is quoting a point without a tolerance. We establish the credible nuclear-data uncertainty on the TBR of a compact spherical-tokamak breeder (design point I_p=9.66, Q=3.076, P_ fus=85.04, δ=-0.30, B_0=8, κ=2.0, R_0=1.20, aspect ratio A=2.5) by casting the TBR as an integral response…
Paper 2.28
P. I. Ford · Kronos Fusion Energy
Every penetration through a breeder's shield is a leak in the neutron account and a source of occupational dose: the ducts that admit heating beams, diagnostics and direct-conversion hardware also let 14 neutrons stream past the blanket, activating the structure the maintainer must later approach. We give a closed, CAD-faithful treatment of that problem for the Hyperion compact spherical-tokamak breeder (P_ fus=85.04, Q=3.076,…
Paper 2.29
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The environmental case for a fusion breeder is settled at end of life, in the activation it accumulates, the waste classes that inventory passes through as it cools, and the ease with which the machine is retired. We report a rigorous activation, waste-routing, and decommissioning account for the Kronos Hyperion breeder — a compact negative-triangularity spherical tokamak operating at P_fus=85.04 MW, I_p=9.66 MA, B_0=8 T, with a…
Paper 2.30
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Activation and waste classification tell you what a fusion structure becomes; they do not tell you how long it survives. We answer the survival question directly for the first wall and plasma-facing components (PFCs) of the Hyperion compact spherical-tokamak breeder (design point I_p=9.66, Q=3.076, P_ fus=85.04, P_n=67.79, neutron wall load _w=1.885, negative triangularity δ=-0.30), computed on an independent, GPU-accelerated code…
Paper 2.31
P. I. Ford · Kronos Fusion Energy
Tritium self-sufficiency in a compact deuterium–tritium breeder is bought by the neutron multiplier, and the choice of multiplier material and its pebble-bed form are the levers that decide whether the blanket breaks even. We qualify the multiplier for the Kronos Hyperion spherical-tokamak breeder (P_ fus=85.04 MW, Q=3.076, I_p=9.66 MA, R_0=1.20 m, aspect ratio A=2.5, B_0=8 T) by solving the steady-state linear Boltzmann transport…
Paper 2.32
P. I. Ford, R. J. Weggel, C. Weggel · Kronos Fusion Energy
For a breeder whose mission is tritium, helium-3 and 14 neutrons—never net electricity—the blanket is the product line, and its design reduces to a concept down-select on one axis: the net tritium breeding ratio (TBR). We state the coupled neutron-transport, fuel-cycle, conjugate-heat-transfer and permeation problems formally, then rank the candidate blanket and neutron-multiplier concepts for the Hyperion breeder (design point…
Paper 2.33
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A fusion breeder's product is tritium, and its credibility rests on an honest mass balance rather than a single optimistic breeding number. We formulate the tritium fuel cycle of the compact spherical-tokamak (ST) breeder Hyperion (design point Q=3.076, P_ fus=85.04, I_p=9.66, δ=-0.30, B_0=8, κ=2.0, R_0=1.20, aspect ratio A=2.5, centrepost peak field 16.84) as a coupled inventory problem and reduce it to three quantities: the…
Paper 2.34
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A deuterium–tritium breeder must know, at all times, where its tritium is: tritium is simultaneously the fuel, the product, and the principal radiological hazard, and it is mobile — it permeates, it is trapped, and it is bred faster than it is burned. Closing the tritium balance in real time to safeguards tolerance therefore rests on two quantities the plant cannot measure directly and must compute: how much tritium is held inside…
Paper 2.35
P. I. Ford · Kronos Fusion Energy
The appeal of a deuterium–helium-3 (D–^3He) burner is its low neutron yield; its obstacle is the fuel itself, because ^3He is not naturally abundant on Earth. A recurring proposal is to close the loop indigenously by breeding tritium in a companion machine and letting it decay to ^3He. We test that closure with a rigorous, first-principles mass balance and report the honest negative: the loop does not close at any realistic…
Paper 2.36
P. I. Ford · Kronos Fusion Energy
The 14.1 MeV fusion neutron sets a compact breeder's tritium breeding, displacement damage, activation inventory and shutdown dose simultaneously, and all four move with the operating point — which is why they belong in a single tracked, verified object rather than in four static reports. We formalise a neutronics-and-activation digital twin for the Kronos Hyperion breeder (=85.04 MW, I_p=9.66 MA, B_0=8 T, negative triangularity…
Paper 2.37
P. I. Ford · Kronos Fusion Energy
Exhausting the power that crosses the separatrix without melting the target is the binding engineering risk of a compact, high-power-density spherical-tokamak (ST) breeder: the machine is small, the parallel heat flux is large, and the scrape-off-layer (SOL) channel is narrow. For the Hyperion breeder design point (I_p=9.66, Q=3.076, P_ fus=85.04, δ=-0.30, B_0=8, κ=2.0, =1.20, aspect ratio A=2.5) the design-basis heat-flux width is…
Paper 2.38
P. I. Ford · Kronos Fusion Energy
The exhaust of a compact, high-power-density spherical tokamak is a down-select problem before it is an engineering one: the parallel heat flux entering the scrape-off layer is two orders of magnitude above what an actively cooled plasma-facing component can accept, and the resolution is a stack of levers rather than a single clever geometry. We evaluate the full advanced-divertor menu for the Hyperion breeder (design point Q=3.076,…
Paper 2.39
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A compact spherical tokamak concentrates its exhaust power onto a small divertor and, in a nuclear device, onto a surface that must not become a tritium reservoir. A solid target erodes, thermally fatigues, and traps tritium; a flowing liquid-metal surface removes the first two failure modes by renewal, but the choice of metal is then set by tritium retention, because in a breeder the divertor is part of the fuel cycle. We formalise…
Paper 2.40
P. I. Ford · Kronos Fusion Energy
A compact, high-power-density spherical-tokamak breeder concentrates its entire exhaust behind a small first wall, and its divertor cannot survive an attached, high-temperature target: detachment is not an operating option but a design requirement, and holding it at full power against disturbances is a real-time control problem. We formalise that problem for the Hyperion breeder (P_ fus=85.04, B_0=8, I_p=9.66, negative triangularity…
Paper 2.41
P. I. Ford · Kronos Fusion Energy
The radiated-power ledger is what keeps a first-wall material honest: every watt an impurity radiates from the core is a watt subtracted from the fusion power balance, and every watt radiated at the edge is a watt usefully removed from the exhaust. For a compact, high-power-density spherical-tokamak breeder armoured in tungsten—the right plasma-facing material and the worst possible core contaminant—this trade must be quantified,…
Paper 2.42
P. I. Ford · Kronos Fusion Energy
The lifetime of a plasma-facing surface is set one incident ion at a time: the ion flux erodes the wall by physical sputtering, part of the eroded material returns by redeposition, and the difference — net erosion — fixes how long an armour tile lasts and how much high-Z material migrates into the plasma. We pose the erosion source term for the plasma-facing surfaces of the Hyperion breeder (design point P_fus=85.04 MW, Q=3.076,…
Paper 2.43
P. I. Ford · Kronos Fusion Energy
The plasma-facing components (PFCs) of a compact breeder live simultaneously inside a hard 14 MeV neutron field, a cyclic surface heat load, and a demount–remate maintenance duty; the engineering question is not whether the wall is loaded but which mechanism sets its life. We pose the coupled thermomechanical, radiation-damage and fatigue problem for the Hyperion breeder at its frozen design point (P_ fus=85.04 MW, I_p=9.66 MA,…
Paper 2.44
P. I. Ford · Kronos Fusion Energy
A compact spherical tokamak concentrates fusion power into a small volume, and the heat it makes must leave through the same small surfaces; whether the machine is buildable is decided at the heat path, not the plasma. We pose the coupled blanket-and-divertor thermal-hydraulic problem for the Hyperion breeder (frozen design point Q=3.076, =85.04 MW, I_p=9.66 MA, δ=-0.30, κ=2.0, B_0=8 T, R_0=1.20 m, aspect ratio A=2.5, centrepost…
Paper 2.45
P. I. Ford · Kronos Fusion Energy
A compact breeder that holds its burn must fuel the core, hold the operating density, and clear the helium ash it makes—all at once and inside a single wall-load budget. We report the closed particle balance for the Hyperion breeder at its frozen design point (P_ fus=85.04, I_p=9.66, Q=3.076, negative triangularity δ=-0.30, B_0=8, κ=2.0, =1.20, aspect ratio A=2.5), cast as a coupled species continuity problem and solved on the…
Paper 2.46
P. I. Ford · Kronos Fusion Energy
Structural and plasma-facing alloys that activate little and clear their radiological classification within a human lifetime are a hard requirement for a compact fusion breeder and the natural home of composition-of-matter design. We report a first-principles screen of refractory multi-principal-element alloys for the first-wall, divertor, breeder-blanket, and direct-energy-converter (DEC) electrode roles of the Hyperion compact…
Paper 2.47
P. I. Ford · Kronos Fusion Energy
The plasma-facing surfaces of a compact spherical-tokamak breeder must keep their strength at high temperature, absorb 14 MeV neutron damage without swelling or embrittling, and decay to a clearable waste class — a combination no legacy plasma-facing alloy meets at once. We report a single radiation-tolerant refractory high-entropy alloy (RHEA), the chromium-free equiatomic W–Ta–V–Ti solid solution, together with the physics that…
Paper 2.48
P. I. Ford · Kronos Fusion Energy
The plasma-facing components of a compact, high-power-density fusion machine must combine refractory strength with low activation: the alloy that survives the heat and the 14 MeV neutrons must not become a long-lived waste problem after shutdown. These two goals normally pull against one another, because the strongest refractory solid solutions are built on tantalum and rhenium, and tantalum activates into the long-lived -emitter…
Paper 2.49
P. I. Ford · Kronos Fusion Energy
The structural steel of a breeding blanket is the one component that must survive every load at once: coolant-temperature strength, retained ductility after displacement damage, resistance to helium-driven swelling, and—the requirement unique to fusion—decay to a hands-on waste class within a human timescale. We qualify a reduced-activation ferritic-martensitic (RAFM, EUROFER/F82H-class Fe–9Cr–W–V–Ta) structure against the specific,…
Paper 2.50
P. I. Ford · Kronos Fusion Energy
The tritium a breeder keeps out of its structure is tritium it keeps in its fuel cycle, and the two decisions that set that balance both live at the first wall: which liquid metal, if any, faces the plasma, and what barrier protects the structure behind it. We resolve both for the Hyperion compact spherical-tokamak breeder (P_ fus=85.04, I_p=9.66, Q=3.076, negative triangularity δ=-0.30, B_0=8, elongation κ=2.0, major radius =1.20,…
Paper 2.51
P. I. Ford · Kronos Fusion Energy
Selecting a plasma-facing structural alloy for a fusion power plant is a search through a combinatorial composition space against two filters a human cannot apply by hand: thermodynamic stability and neutron activation. A refractory-alloy palette that is mechanically excellent but activates into a long-lived waste class is useless to a plant, and discovering this only after the mechanical case is built wastes the search. We…
Paper 2.52
P. I. Ford · Kronos Fusion Energy
A D–^3He tandem mirror trades the closed field lines of a torus for an open, linear geometry whose engineering gain is set not by confinement time alone but by the ambipolar potential a high-field plug can hold. We map the design space of the Kronos burner with a zero-dimensional power balance closed by a Pastukhov–Fokker–Planck end-loss model, deriving the governing equations from the mirror loss cone, the Boltzmann plug potential,…
Paper 2.53
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
In a deuterium–helium-3 (D–^3He) tandem-mirror burner the fusion-born 14.68 MeV proton and 3.67 MeV alpha carry the overwhelming majority of the released power as fast, mirror-trapped ions. Left to thermalise, that energy is shared between electron drag and a broadly heated ion background whose confined, usefully recoverable share is small; the rest exits the loss cone as heat and inflates the recirculating power that sets the…
Paper 2.54
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The end plug of a deuterium–helium-3 tandem-mirror burner confines the central-cell ions behind a large positive ambipolar potential, but the loss-cone velocity distribution that builds that potential is a free-energy reservoir for the drift-cyclotron loss-cone (DCLC) instability — historically the mode that limited mirror-plug performance. We resolve, quantitatively, whether the Kronos burner plug is DCLC-stable at its frozen…
Paper 2.55
P. I. Ford · Kronos Fusion Energy
Unlike a deuterium–tritium tokamak, a hot deuterium–helium-3 (D–^3He) tandem-mirror burner is radiation-dominated: at the electron temperatures required for advanced-fuel reactivity the plasma loses more power to electron-cyclotron (synchrotron) emission than to any other charged-particle channel, and that loss is what fixes the optimal electron temperature. We formulate the coupled emission–absorption problem for the burner central…
Paper 2.56
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The recirculating power of a tandem-mirror fusion burner is set almost entirely by the electrostatic potential the end plugs must raise to confine the central-cell ions, and in a deuterium–helium-3 (D–^3He) machine that potential is large: the frozen Kronos burner design point demands an ion-confining potential 248.75 keV at an ion temperature 90 keV (e/ = 2.764), a mirror ratio =4.61, and an engineering gain Q_E=1.318 that sits…
Paper 2.57
P. I. Ford, R. J. Weggel, C. Weggel · Kronos Fusion Energy
The engineering gain of a D–^3He tandem-mirror burner is set, through an exponential Pastukhov confinement law, by the ambipolar potential that its high-field end plug can hold; whether that potential forms in the confining shape, where on the density-ratio trade the machine should sit, and whether the plug is microstable there are the three questions that decide the plug. We formalise the plug as a coupled electrostatic–kinetic…
Paper 2.58
P. I. Ford, R. J. Weggel, C. Weggel · Kronos Fusion Energy
Axial confinement is the headline number of a tandem mirror, but it is physically meaningful only after two prior gates are cleared: the central cell must be stable against sideways (interchange/ballooning) magnetohydrodynamic (MHD) motion, and its loss-cone distribution must not drive velocity-space microinstabilities that dump particles and energy. We formalise and evaluate those gates for the Kronos D–^3He tandem-mirror burner at…
Paper 2.59
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The ends of a tandem mirror set its loss budget: the depth of the confining potential, the stability of the plug, and the way the unavoidable end-loss stream is spread and recovered determine whether the whole machine confines. We report the end-cell, expander and halo physics of the Kronos D–^3He tandem-mirror burner at its frozen operating point (Q_E=1.318, neutron fraction f_n=5.44 %, plug-coil peak on-conductor field 26.49 T,…
Paper 2.60
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The end cell of a tandem-mirror burner must simultaneously keep the plug plasma micro-stable, set the mirror ratio that trades engineering gain against axial end loss, and expand the escaping flux tube onto a survivable end wall—and each of these three tasks admits more than one physical solution. We pose the three problems as a single coupled optimisation for the Aegis deuterium–helium-3 burner, derive the governing relations, and…
Paper 2.61
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A power-producing magnetic mirror is judged not by its physics gain but by its recirculation-resolved engineering gain P_ gross/P_ recirc, the ratio of gross electrical output to the electrical power that must be pumped back into the plug and thermal-barrier drive to keep it burning. We report a zero-dimensional, self-consistent power balance for the Kronos D– tandem-mirror burner — a Pastukhov-plugged central cell shared by the…
Paper 2.62
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Where a fusion machine may be built is decided largely by its neutrons, and the Kronos burner is neutron-lean by design so that it can be sited where a conventional D–T source cannot. Problem: the D–^3He cycle is only predominantly aneutronic — a residual neutron budget survives from unavoidable D–D reactions and from the D–T self-burn of the tritons those reactions breed — and a defensible siting case must resolve that budget, fix…
Paper 2.63
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A D–^3He tandem-mirror burner deposits the bulk of its useful output not as neutrons but as a stream of fast charged particles that leave the machine along open field lines. A direct energy converter (DEC) decelerates that stream against a graded set of collector electrodes and draws the kinetic energy off as high-voltage direct current, with no thermal cycle. We give a formal, first-principles account of the collector physics for…
Paper 2.64
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A deuterium–helium-3 tandem-mirror burner deposits most of its fusion power in charged particles that leave the machine axially as a fast, directed ion stream, so the direct-energy converter (DEC) is the single component that sets the plant's electrical efficiency. The architecture that supplies the frozen module efficiency ηdec=0.70 is not, however, uniquely determined by that number: three collector families—the periodic…
Paper 2.65
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A forward operating base must generate its own power without a grid, a fuel convoy, or a favourable threat environment. Aegis is the Kronos deuterium–helium-3 (D–) tandem-mirror burner packaged as a hardened, fixed defense installation; because its reaction is largely aneutronic and its electrical output is taken from an electrostatic direct energy converter (DEC) rather than a steam cycle, it is unusually well matched to…
Paper 2.66
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A compact D^3He tandem-mirror burner sited next to the load it serves is not merely a reactor but a facility, and a critical facility is held to reliability, efficiency, and heat-management standards that no plasma-physics result answers. We formalise the facility-integration problem for the Kronos MetroVolt burner (design point ≈850 net electric at a recirculating fraction of 0.76; burner physics Q_E=1.318, plug field 26.49,…
Paper 2.67
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A fusion generator built around direct energy conversion (DEC) is not an alternating-current machine wearing a direct-current mask: it is intrinsically a high-voltage direct-current (HVDC) source, and that fact reshapes the electrical interface between the reactor and its load. We formalise that interface for the MetroVolt D–^3He tandem-mirror data-center burner and reduce it to a set of governing equations and a verified numerical…
Paper 2.68
P. I. Ford · Kronos Fusion Energy
The MetroVolt burner takes a deuterium–helium-3 (D–^3He) tandem mirror and delivers its output as electricity to a co-located, high-density computing load. Because the burner's direct-energy converter (DEC) decelerates a charged-particle stream against graded collectors, it is a high-voltage DC source by construction, and the power-delivery architecture becomes a set of down-select decisions that a conventional AC plant never faces.…
Paper 2.69
P. I. Ford · Kronos Fusion Energy
A nuclear-regulated fusion machine must guarantee that every automated actuation keeps the plasma inside a declared safe operating envelope, and it must do so in a way an auditor can check, not merely trust. Learned and optimisation-based controllers deliver performance but, by themselves, provide no such guarantee. We formalise and verify a deterministic, control-barrier-certified safety filter for a compact spherical-tokamak (ST)…
Paper 2.70
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A controller or a learned advisor on a nuclear-regulated machine should be trusted with exactly as much authority as the evidence behind its models can justify — no more, and no less than the evidence has earned. On a compact, high-power-density spherical tokamak the reaction times are short and every actuation carries a safety consequence, so the question ``how much authority should the automation have?'' cannot be answered by…
Paper 2.71
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Every control decision in a compact spherical tokamak begins with the equilibrium, and in a nuclear device that equilibrium must be reconstructed faster than the plant, verified against the governing physics, and kept trustworthy when a diagnostic degrades or drops out under a neutron field. We formalise and demonstrate a real-time reconstruction stack for the Hyperion breeder (design point I_p=9.66, Q=3.076, P_ fus=85.04, negative…
Paper 2.72
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A predictive digital twin must evaluate turbulent transport faster than the plasma evolves, yet a nonlinear gyrokinetic flux is many orders of magnitude too slow for a control loop and even a quasilinear model is a heavy call at kilohertz rates. We formalise the transport-emulation problem as the learning of a solution operator _:a(x) u(x) between the local-state function space and the turbulent-flux function space, and we…
Paper 2.73
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Autonomous operation of a compact, high-power-density spherical tokamak leaves little time to react and no tolerance for an unmodelled excursion, so the controller must act on a model that runs ahead of the plant across every coupled physical domain at once. We formalise a four-twin real-time architecture for the Hyperion breeder (design point I_p=9.66, Q=3.076, P_ fus=85.04, negative triangularity δ=-0.30, B_0=8, elongation κ=2.0,…
Paper 2.74
P. I. Ford · Kronos Fusion Energy
A burn controller has two duties that pull against each other: hold the fusion gain at its set-point against disturbances, and never allow the plasma to cross a stability limit. The first is a performance problem, ideally suited to model-predictive control (MPC); the second is a safety problem, and a controller merely tuned to stay clear of a limit offers no guarantee that it always will. We separate the two by construction for the…
Paper 2.75
P. I. Ford · Kronos Fusion Energy
A compact, high-current spherical tokamak leaves little time to react and no room for an uncontrolled excursion, so its controllers must be simultaneously fast, coordinated, and provably safe. We present the real-time control suite for the Hyperion breeder (design point =9.66, Q=3.076, P_ fus=85.04, negative triangularity δ=-0.30, on-axis field B_0=8, elongation κ=2.0, major radius =1.20, aspect ratio A=2.5, centrepost peak field…
Paper 2.76
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A tandem-mirror burner is held together by its end plugs: a small warm-ion population sustains the ambipolar potential that electrostatically confines the central cell, and the burner's electrical gain lives or dies on whether that plug can be held on — not past — its velocity-space microstability margin. We formalise the real-time control suite for the Kronos D–^3He tandem-mirror burner (electrical gain =1.318, neutron power…
Paper 2.77
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
In a nuclear control system a model that is confidently wrong is more dangerous than one that admits it does not know. We formalise the uncertainty a learned fusion controller must carry, prove what its intervals are allowed to mean, and specify how it hands control back to a deterministic floor when it is asked to extrapolate. The substrate is a 40,000-sample Monte-Carlo propagation of the operating uncertainties through the…
Paper 2.78
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Autonomy in a nuclear plant is acceptable only if a certified, non-learned component always has the last word, and only if every action that component allows is on an incorruptible record. We formalise and reduce to practice the Kronos last-line-of-defense architecture: a certified control-barrier-function (CBF) safety projection at the base of an autonomous controller, backed by a hardware quench-dump failsafe with no AI in its…
Paper 2.79
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A learned controller extrapolates smoothly and confidently into regions where it has no evidence, and in a nuclear system that confident wrongness off-distribution is the dominant failure mode. The safeguard is not a better model but an honest one: a controller that measures the boundary of its own competence in real time and refuses authority beyond it. We formalise the epistemic-gating layer of the Kronos autonomous fusion…
Paper 2.80
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A first-of-a-kind fusion breeder has no operating record of its own, so its disruption-prediction model must be born from other machines' data — and it must know how far it is being asked to reach. We formalise cross-machine transfer learning for the Hyperion compact spherical-tokamak breeder (frozen design point I_p=9.66, Q=3.076, P_ fus=85.04, negative triangularity δ=-0.30, B_0=8, elongation κ=2.0, major radius =1.20, aspect…
Paper 2.81
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Reinforcement learning (RL) improves a controller by exploring, and on a nuclear fusion plant unconstrained exploration is precisely what must never happen. We formalise and demonstrate safe reinforcement learning from operator feedback for the Kronos controller of a compact negative-triangularity spherical-tokamak breeder (design point operating limit 3.5; I_p=9.66, Q=3.076, P_ fus=85.04, δ=-0.30, B_0=8, κ=2.0, =1.20, aspect ratio…
Paper 2.82
P. I. Ford · Kronos Fusion Energy
A controller that holds a nuclear plasma must answer, on every cycle, two questions a regulator will ask: what will this action do, and why did you take it. Correlational machine learning answers neither; both are causal questions, and a control action is not an observation but an intervention. We formalise the Kronos digital twin of the Hyperion breeder (design point I_p=9.66, Q=3.076, P_ fus=85.04, negative triangularity δ=-0.30,…
Paper 2.83
P. I. Ford · Kronos Fusion Energy
A machine-learning model that touches a nuclear plant must earn its authority the way any safety-critical software does: by passing an explicit, reproducible gate before it acts. We formalise the machine-learning-operations (MLOps) layer of the Kronos control stack for the Hyperion compact spherical-tokamak breeder (design point Q=3.076, P_ fus=85.04 MW, I_p=9.66 MA, negative triangularity δ=-0.30, on-axis field B_0=8 T, elongation…
Paper 2.84
P. I. Ford · Kronos Fusion Energy
An autonomous controller can act only on the state it can see, and in a compact spherical tokamak the state must be produced faster than the plant evolves, from a diagnostic set that survives a 14 neutron field and keeps working when individual channels drop out. We formalise the Hyperion breeder diagnostic suite — magnetics, Thomson scattering, interferometry, bolometry, and a neutron camera — and its real-time state estimator as a…
Paper 2.85
P. I. Ford, R. J. Weggel, C. Weggel · Kronos Fusion Energy
The inboard centrepost of a compact spherical-tokamak (ST) breeder is not a lifetime component: behind a practical inboard shield the fast-neutron fluence degrades the no-insulation REBCO conductor and its copper stabiliser to end of life within a fraction of a full-power year, so the machine is designed to swap the centrepost as a scheduled consumable cartridge. When to swap it is therefore a control decision, and a single…
Paper 2.86
P. I. Ford · Kronos Fusion Energy
Autonomous operation of a nuclear fusion plant requires the machine to act faster than any human can react, and yet requires a human to remain unambiguously in command of what the machine is allowed to do. We formalise the human-machine layer that reconciles these requirements for the Kronos compact spherical-tokamak breeder (design point Q=3.076, P_ fus=85.04, I_p=9.66, negative triangularity δ=-0.30, B_0=8, elongation κ=2.0, major…
Paper 2.87
P. I. Ford · Kronos Fusion Energy
Real-time control of a compact, high-power-density spherical tokamak is a constrained optimization problem that must be solved to a certified answer inside each control period, every period; the controller is only as trustworthy as its ability to solve that program fast, accurately, and safely. We formalise the optimization backbone that makes this tractable for the Kronos Hyperion breeder (design point I_p=9.66 MA, Q=3.076, P_…
Paper 2.88
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A frozen design point is only as trustworthy as its behaviour under joint parameter uncertainty, yet fusion performance is almost always reported as a single number for each figure of merit. We resolve two questions globally — where does the design anchor sit in the distribution of achievable outcomes, and which uncertain input actually drives that distribution — for the two Kronos machines, the Hyperion compact spherical-tokamak…
Paper 2.89
P. I. Ford · Kronos Fusion Energy
Designing a compact fusion machine means running many expensive simulations, and the most expensive of them — nonlinear gyrokinetic transport — cannot be run everywhere in the operating envelope. A finite simulation budget therefore has to be spent where it is worth the most. We formalise and demonstrate a Bayesian design system for the Kronos machines built on three ideas that share one probabilistic core: a Gaussian-process…
Paper 2.90
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Quantum computing is routinely invoked for fusion without a disciplined account of what is reachable now and what is a fault-tolerant-horizon problem. We supply that account for a specific machine — the Kronos Hyperion compact spherical-tokamak breeder (design point I_p=9.66, Q=3.076, P_ fus=85.04, negative triangularity δ=-0.30, B_0=8, elongation κ=2.0, major radius R_0=1.20, aspect ratio A=2.5, centrepost peak field 16.84) and its…
Paper 2.91
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Real-time control of a compact spherical-tokamak breeder poses, at several points, a combinatorial-optimization problem inside a control cycle: which actuators to schedule, how to lay out a discrete blanket, and — the control-relevant case — how to sequence poloidal- and toroidal-field coil currents under hard constraints while tracking a shape and vertical-position target. Because these problems are naturally binary and quadratic,…
Paper 2.92
P. I. Ford, R. J. Weggel, C. Weggel · Kronos Fusion Energy
Quantum computing and quantum sensing are routinely proposed as accelerants for fusion; a serious design program should test those proposals quantitatively rather than assume them. We deliver a resource-honest map of where the quantum toolbox helps a compact spherical-tokamak breeder and its tandem-mirror burner, and where it does not, formalised as three coupled estimation problems and computed on a single GPU-HPC campaign. On the…
Paper 2.93
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The real-time control loop of a compact spherical-tokamak breeder must reconstruct the equilibrium, watch for disruptions, and shape the plasma edge faster than a 9.66 plasma at =1.20 can move — a loop served today by classical GPU surrogates and a demonstrated in-winding quantum sensor. This paper asks, and answers with equal weight on both sides, where a quantum computer (as distinct from a quantum sensor) could accelerate that…
Paper 2.94
P. I. Ford · Kronos Fusion Energy
The Kronos burner sustains an advanced-fuel D–^3He plasma in a tandem magnetic mirror whose end plugs are held by a coil at a peak field of 26.49; two things must go right in real time, and both are quantitative. The plug and mirror-throat fields must be read accurately enough to hold the ambipolar confinement, and the velocity-space burn kinetics that set the plug potential and the fusion rate must be solved fast enough to control.…
Paper 2.95
P. I. Ford, R. J. Weggel, C. Weggel · Kronos Fusion Energy
Screening the low-activation alloys that make up a fusion reactor's plasma-facing and structural components by density-functional theory (DFT) runs into a wall: on the correlated 3d transition metals that constitute the family, the computed energetics depend on the exchange–correlation functional at the level of hundreds of millihartree, which is comparable to or larger than the composition differences the screen must resolve. A…
Paper 2.96
P. I. Ford · Kronos Fusion Energy
Kinetic descriptions of fusion plasmas are throttled by the curse of dimensionality: a distribution function on a six-dimensional phase space is intractable to store on a dense grid, let alone to advance in time. We show that the kinetic distribution function is strongly compressible in a low-rank tensor-network (matrix-product-state, or tensor-train) representation and that this yields a practical solver on present-day classical…
Paper 2.97
P. I. Ford · Kronos Fusion Energy
A compact-fusion design program that makes quantitative public claims is only as credible as those numbers are reproducible: a competent third party must be able to regenerate every headline value from deposited code and data, and the load-bearing numbers must survive a change of code and of evaluated nuclear-data library. We formalise and report the verification-and-validation (V&V) discipline applied across the Kronos 2026…
Paper 2.98
P. I. Ford · Kronos Fusion Energy
The Hyperion breeder stakes its confinement on a single physics choice: that strong negative triangularity (δ=-0.30) places the plasma core in a quiet, subcritical turbulence basin. A claim of that weight must not rest on one code. Here we cross-validate the claim with two independent members of the GACODE family evaluated on the identical frozen design case (config-22021: =1.20, a=0.48, κ=2.0, δ=-0.30, B_0=8, q_95=3.0, at the…
Paper 2.99
P. I. Ford · Kronos Fusion Energy
A design frozen for construction is only as credible as the solvers behind it, and a solver is only as credible as its provenance. We present the verification backbone of the Kronos physics de-risking campaign, which de-risks a compact spherical-tokamak breeder (design point Q=3.076, P_ fus=85.04MW, I_p=9.66MA, negative triangularity δ=-0.30, B_0=8T, elongation κ=2.0, major radius =1.20m, aspect ratio A=2.5, centrepost peak field…
Paper 2.100
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A breeder's operating point is not chosen freely; it is boxed in by competing mission and lifetime constraints, and the shape of that box — its floors, its ceilings, and which of them actually bind — is a design result in its own right. We synthesise the admissible operating window of the Hyperion compact spherical-tokamak breeder (design point I_p=9.656 MA, Q=3.076, P_fus=85.04, negative triangularity δ=-0.30, B_0=8, elongation…
Paper 2.101
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
A design that publishes its negatives is honest; a design that then bounds whether each negative can be closed is useful. We formalise and execute an adversarial red-team of the binding engineering gates of a compact, negative-triangularity spherical-tokamak breeder (Q=3.076, =85.04, I_p=9.66, δ=-0.30, B_0=8, κ=2.0, =1.20, aspect ratio A=2.5, centrepost peak field 16.84) and its separate deuterium–helium-3 tandem-mirror burner…
Paper 2.102
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Between a fusion core and the grid sits the balance of plant (BOP), and beneath the whole machine sit the cryogenic and vacuum services that keep the cold mass superconducting and the chamber evacuated. We formalise the BOP of the Kronos Hyperion breeder as a coupled thermal–fluid–cryogenic–vacuum system and reduce it to a set of governing equations, a numerical formulation, and a demonstrated design envelope. At the ratified design…
Paper 2.103
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The heating and current-drive (H&CD) system is what holds a compact breeder's operating point in place, and in a solenoid-poor spherical tokamak (ST) it must sustain almost the entire plasma current non-inductively. We derive and specify that system for the Hyperion breeder from first principles and from frozen, independently reproduced design results. The duty is fixed by the design point: sustain I_p=9.66 at =1.20, B_0=8, κ=2.0 in…
Paper 2.104
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The Hyperion breeder is built around a consumable centrepost — a demountable high-temperature-superconducting (REBCO) toroidal-field column that is swapped on a schedule rather than designed to survive the plant lifetime. That architectural choice converts a hard material-lifetime problem into an operations problem, and the operations problem decides whether the machine is viable. We give it a quantitative, first-principles…
Paper 2.105
P. I. Ford · Kronos Fusion Energy
A fusion plant is paid for the calendar hours it delivers, so a fleet's reliability case must be quantified with the same rigour as its physics case. We formalise and solve the fleet-availability problem for a compact spherical-tokamak breeder — design point I_p=9.66, Q=3.076, P_ fus=85.04, negative triangularity δ=-0.30, B_0=8, elongation κ=2.0, major radius R_0=1.20, aspect ratio A=2.5, centrepost peak field 16.84 — whose inboard…
Paper 2.106
P. I. Ford, R. J. Weggel, C. Weggel · Kronos Fusion Energy
A machine that closes on physics can still fail to be built if its critical materials cannot be procured at fleet rate and on the program clock. We pose fleet buildability as a formal feasibility problem—coverage and lead time against demand, with cost held strictly internal and out of scope—and solve it for the Hyperion compact spherical-tokamak breeder (design point I_p=9.66, Q=3.076, P_ fus=85.04, negative triangularity δ=-0.30,…
Paper 2.107
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
Fusion's radiological advantages are real, but a credible safety case must bound them: name the dominant hazard, propagate a defensible source term through the atmosphere, and translate the result into an emergency-planning distance a regulator can act on. We build that chain end-to-end for the Hyperion compact spherical-tokamak (ST) breeder (design point Q=3.076, P_ fus=85.04, I_p=9.66, negative triangularity δ=-0.30, B_0=8,…
Paper 2.108
P. I. Ford, G. L. Kulcinski · Kronos Fusion Energy
The regulatory pathway is as decisive for a fusion plant as its physics, and it is not chosen by assertion: it is fixed by the statutory definition of the facility and, for the graded case, by a quantitative dose bound. We give a first-principles regulatory-strategy analysis for the Hyperion compact spherical-tokamak (ST) breeder (design point Q=3.076, P_ fus=85.04, thermal power P_ th=95.2, I_p=9.66, B_0=8, negative triangularity…
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