Estimating Potential Tritium and Plutonium Production in North Korea's Experimental Light Water Reactor

Alexander Glaser; Patrick J. Park

REVIEW 3 major objections 3 minor 12 references

Estimating Potential Tritium and Plutonium Production in North Korea's Experimental Light Water Reactor

T0 review · 3 major / 3 minor · reviewed 2026-08-11 · deepseek-v4-flash

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Pith's one-line read The ELWR at Yongbyon could, on a single-batch core, produce 48-82 grams of tritium per year and up to 15 kg of weapon-grade plutonium, giving North Korea its first robust domestic tritium source.

desk verdict Useful and honest scenario analysis, but the paper's own co-production numbers undercut the advertised tritium upper bound. read the letter →

arxiv 2412.11993 v1 pith:2L4O5VYY submitted 2024-12-16 physics.ins-det

Patrick J. Park , Alexander Glaser This is my paper · ORCID

classification physics.ins-det

keywords tritiumproductionplutoniumELWRYongbyonNorthKoreanuclearprogramlightwaterreactorneutronicssimulationboostedweapons

verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

The paper argues that North Korea's 100 MWth Experimental Light Water Reactor (ELWR), which started up in October 2023, is a dual-use facility that could substantially expand the country's nuclear weapons options. Using full-core neutronics, the authors estimate that a single-batch core with lithium targets could yield 48-82 grams of tritium per year, enough to sustain a stockpile of up to 88-150 boosted warheads or to add 2-4 new warheads annually. Alternatively, the reactor could co-produce up to 15 kg of weapon-grade plutonium per year, though this requires reprocessing ceramic fuel. The exact rates hinge on cladding material and core configuration, with zircaloy cladding roughly doubling tritium output compared with stainless steel. The significance is that the ELWR would provide North Korea with its first dedicated, sustained tritium production capability, which could enable lighter and more efficient boosted primaries.

What carries the argument

The central mechanism is the loading of lithium-6 into the reactor (modeled as part of the cladding), where neutron capture on Li-6 produces tritium. Because lithium adds negative reactivity, the paper fits a quadratic k-penalty function to MCNP6 pin-cell results, mapping lithium concentration to reactivity loss, and then solves a convex optimization problem to find the lithium loading that maximizes tritium output before the core reaches end-of-cycle at keff = 1.03. Full-core depletion is carried out with MCODE, which couples MCNP6 with ORIGEN2.

What would settle it

A year of satellite thermal monitoring showing the ELWR operating at an average power well below 100 MWth, or observation of partial refueling (multi-batch) operations, would directly contradict the single-batch full-power assumption and reduce the estimated production rates.

Watch

Extended reading notes

Core claim

Under the paper's model, the ELWR can be configured in three ways: a clean core for maximum burnup, a tritium core optimized for lithium-6 loading, and a co-production core that stops at low burnup so the plutonium remains weapon-grade (90% Pu-239). For the tritium core, optimal lithium-6 loading of about 122 mg/kg of uranium yields 95.4 grams of tritium per cycle (82.2 g/yr with zircaloy cladding) and 42.5 grams per cycle (48.3 g/yr with stainless steel). The co-production core produces 56-116 grams of tritium per year and 15-15.6 kg of plutonium per year, but requires reprocessing of spent ceramic fuel and about 25,000 SWU/yr if natural uranium feed is used. The authors conclude that the ELWR offers the first robust tritium source for North Korea's weapons program.

Load-bearing premise

The whole production estimate rests on the assumption that the ELWR runs a single-batch core at full power with about 4,000 kg of 3.5%-enriched UO2 and a fixed end-of-cycle reactivity; if any of these is off, the tritium and plutonium rates change roughly proportionally.

Editorial extensions

If this is right

If the ELWR is operated as a tritium core, North Korea could produce enough tritium to sustain a boosted arsenal of up to 88-150 warheads, more than doubling the currently estimated ~50-warhead stockpile.
Annual tritium production of 48-82 grams could support 2-4 new boosted warheads per year while replenishing decay losses, assuming 10 grams per warhead.
Co-production mode could yield up to 15 kg of weapon-grade plutonium per year, a substantial increase over the ~6 kg/yr from the old 5 MWe graphite reactor, albeit requiring ceramic fuel reprocessing.
Resource demands (natural uranium, separative work) roughly double for tritium mode and quadruple for co-production mode, which could strain North Korea's enrichment capacity.
The cladding choice is decisive: zircaloy cladding roughly doubles tritium production and reduces fuel demands compared to stainless steel, so observing the cladding type would sharply constrain estimates.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

The paper treats single-batch operation as a modeling convenience, but if North Korea adopts multi-batch fuel management, tritium production rates drop; the 48-82 g/yr figures are best read as upper bounds rather than expected values.
A driver-target fuel assembly design, which the paper explicitly sets aside, could decouple tritium and plutonium production and may be more attractive if North Korea wants both materials without reprocessing ceramic fuel.
The tritium-per-warhead assumption of 10 grams is derived from U.S. stockpile estimates; if North Korea uses less or more tritium per device, the 88-150 range scales inversely.

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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Desk Editor's Note

read the letter

You should know this about the ELWR tritium paper: it is a genuine contribution—the first public modeling of tritium production in North Korea's new experimental light-water reactor—and it is honestly done. The method is standard MCODE (MCNP6 + ORIGEN2), applied carefully to a reactor that only started up in 2023. The paper lays out six core configurations with transparent assumptions, and the tables are internally consistent: per-cycle values annualized with the stated 30-day outage reproduce the annual rates. The cladding comparison is useful, and the resource requirements are grounded. No curve-fitting or circularity.

The main soft spot is real, and the stress-test note is correct. The tritium core's lithium loading is optimized to maximize tritium per cycle, not per year. Table 1 shows the co-production core with a shorter cycle and higher lithium loading producing 115.6 g/yr for zircaloy, versus 82.2 g/yr for the dedicated tritium core. So the abstract's '48–82 g/yr' and '88–150 warheads' is not the model's true upper limit; the co-production scenario would sustain roughly 211 warheads at equilibrium. This undercuts the 'maximum arsenal' framing. The paper either needs to re-optimize with annual tritium as the objective or clearly qualify that the headline applies only to the dedicated tritium core, not to the maximum possible tritium.

Other soft spots are less serious. There is no sensitivity or uncertainty analysis; core inventory, enrichment, power, and single-batch operation are all assumed, and the paper says so. Results would shift roughly proportionally, but a sensitivity table would help. Also, no MCNP inputs or depletion files are provided, limiting full reproducibility. That is a minor issue for policy-relevant modeling, but worth noting.

This paper deserves peer review. It addresses a real gap in public nonproliferation assessment and is clearly the work of careful analysts. I would send it out with a request to fix the annualization inconsistency and add at least a basic sensitivity analysis. After that, I would cite it.

Referee Report

3 major / 3 minor

Summary. This paper estimates potential tritium and plutonium production in North Korea's 100 MWth experimental light-water reactor (ELWR) using full-core MCNP6/ORIGEN2 depletion calculations. It models three core configurations (clean, tritium, and tritium-Plutonium co-production) with either zircaloy or stainless-steel cladding, and reports per-cycle and annual production rates, fuel-cycle requirements, and weapon-stockpile implications. The central claims are that a dedicated tritium core can produce 48-82 grams of tritium per year, sustaining an arsenal of 88-150 boosted warheads, and that co-production can yield up to 15 kg of weapon-grade plutonium per year with 56-116 grams of tritium per year, depending on cladding. However, the paper's own tables show that the co-production configurations produce more tritium per year than the dedicated tritium cores, contradicting the advertised 48-82 grams per year as the upper limit.

Significance. If the model is credible, the ELWR would be a significant dual-use facility: a robust tritium source and a potential source of weapon-grade plutonium, with direct implications for assessments of North Korea's nuclear arsenal. The paper's strengths include transparent, full-core neutronics calculations, six well-defined scenarios, stated assumptions, and internally consistent per-cycle-to-annual conversion. The use of MCODE/MCNP6 is standard, and the 10 grams-per-warhead allocation and 5.47% tritium decay rate are traceable to declassified sources. The main weakness is not the physics but the synthesis: the headline numbers misstate the model's own upper bound, because the co-production rows in Tables 1 and 2 exceed the dedicated tritium-core numbers that the abstract and conclusion present as the maximum. Correcting this inconsistency and adding a sensitivity analysis would make the paper a useful upper-bound assessment for policy audiences.

major comments (3)

[Abstract; Co-Production section; Tables 1 and 2] Tables 1 and 2 report co-production annual tritium rates of 115.6 g/yr (zircaloy) and 56.0 g/yr (stainless steel), both of which are higher than the dedicated tritium-core rates of 82.2 g/yr and 48.3 g/yr, respectively. The text explicitly notes that co-production tritium 'is even higher than the annual production rates obtained for the tritium core.' Yet the abstract and conclusion state that the ELWR can produce 48-82 grams of tritium per year and sustain a 'maximum arsenal of 88-150 warheads.' These statements are internally inconsistent: under the paper's own model, the true upper bound on annual tritium production is higher if co-production is considered. At 10 grams per warhead and 5.47% annual decay, the zircaloy co-production rate of 115.6 g/yr sustains roughly 211 warheads, not 150. Please revise the headline to report the full range across all modeled configurations, or clearly designate the 48-82 g/yr as the dedicated-tritium-core result and recompute the warhead ceiling accordingly.
[Tritium Core; Figure 3] The lithium loading is optimized to 'maximize the total tritium produced by the end of the cycle,' but the headline results are annual rates. Maximizing per-cycle production is not equivalent to maximizing annual production when the cycle length varies, because a shorter cycle with more frequent refueling can yield more tritium per year. The co-production results illustrate this: the 198-day cycle with higher lithium-6 loading produces 115.6 g/yr in the zircaloy case, versus 82.2 g/yr for the longer 393-day tritium-cycle case. The optimization should be rerun with an annual objective, T_per_year = T_per_cycle/(cycle_length + 30 days), or the paper should explicitly state that the reported 48-82 g/yr is not the annual optimum. This point is load-bearing for the central policy claim about tritium supply.
[Reactor Model and Neutronics Calculations; Discussion] The paper presents the production rates as upper bounds but provides no sensitivity analysis for the key assumed reactor state: 4,000 kg UO2, uniform 3.5% enrichment, 100 MWth, single-batch operation, and keff = 1.03 at end of cycle. Tritium and plutonium production rates scale roughly linearly with power and core inventory, and enrichment and loading pattern affect cycle length and discharge burnup. A sensitivity table varying power (e.g., ±10%), inventory (e.g., ±10%), enrichment (e.g., 3.0-4.0%), and end-of-cycle keff would be needed to support the claim that 48-82 g/yr is a robust upper-bound estimate. Without it, the quoted range reflects only the cladding-material variation, not the model's parametric uncertainty.

minor comments (3)

[Throughout] The acronym is inconsistent: the title and abstract use 'EL WR' with a space, the body uses 'ELWR' without a space, and the Discussion contains the typo 'EWLR'. Please standardize to 'ELWR' throughout.
[Reactor Model] The phrase '5×5 grid of 21 fuel assemblies' is confusing because a 5×5 grid has 25 positions; clarify whether the remaining four positions are occupied by non-fuel elements such as control rods or reflectors, or correct the wording to describe the actual assembly layout.
[Figure 3 caption] The caption states that numerical results are obtained by 'solving a convex optimization problem'; please justify the convexity claim or rephrase, since the paper does not demonstrate that the fitted k-penalty function yields a convex objective over the relevant lithium-loading range.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: tritium and plutonium estimates are outputs of full-core depletion calculations, not recovered from the headline quantities.

full rationale

The paper's central derivation chain is self-contained: the ELWR core geometry, 4,000 kg UO2 inventory, 3.5% enrichment, 100 MWth power, and single-batch operation are stated external inputs from reporting and site observations, while the tritium and plutonium rates are outputs of MCODE/MCNP6-ORIGEN2 depletion calculations. The only fitting step is a quadratic k-penalty surrogate used to optimize lithium loading; this is an internal calibration of a reactivity model, and the resulting tritium masses are still produced by the depletion calculation rather than recovered from the target numbers. The 10 grams-per-warhead and 5.47%-per-year decay conversion factors are taken from declassified U.S. sources and the known tritium half-life, respectively, so the warhead-equivalent claims are not defined in terms of the model outputs. The co-production rows (115.6 g/yr for zircaloy) exceed the abstract's 48–82 g/yr range, but the paper presents co-production as a distinct scenario; this is at most an internal emphasis or bounding inconsistency, not a circular derivation. No load-bearing self-citation or imported uniqueness theorem appears: the cited prior work supplies benchmarked code and external design information, not the paper's conclusions.

Assumptions & free parameters 9 free parameters · 6 assumptions · 0 invented entities

The central claim depends on a chain of unverified engineering assumptions (power, core inventory, enrichment, cladding, lithium loading, refueling schedule). These are disclosed and mostly parameterized as upper-bound scenarios rather than hidden fits, but the absence of a sensitivity analysis means the headline numbers should be read as scenario outputs, not robust predictions.

free parameters (9)

Core thermal power = 100 MWth
Reported nominal power adopted as reference; all annual production rates scale near-linearly with power.
Core UO2 inventory = 4000 kg
Reported core inventory used as reference for all six core variants.
Fuel enrichment = 3.5 wt% U-235 uniform
Chosen from reported 2.2-4.0% range; no loading-pattern sensitivity analysis is provided.
Cladding variants = Zircaloy-4 0.573 mm; SS 304 0.400 mm
Two materials bound performance; cladding choice is the main driver of the 48-82 g/yr tritium range.
End-of-cycle keff threshold = 1.03
Assumed shutdown margin; changing this threshold changes cycle length and annual outputs.
Lithium-6 loading = 122/161 mg/kgU (zircaloy), 70/90 mg/kgU (stainless steel)
Optimized using a quadratic k-penalty fit to MCNP6 pin-cell data; the optimum depends on the surrogate fit.
Annualization outage = 30 days per cycle
Assumed refueling outage used to convert per-cycle values to annual rates.
Tails assay = 0.27%
Reported North Korean enrichment practice; affects SWU and uranium demand, not tritium/Pu rates.
Tritium per warhead allocation = 10 g/warhead
Midpoint of declassified US figures cited in Endnote 20; converts tritium mass to warhead counts.

assumptions (6)

domain assumption MCNP6 and ORIGEN2 cross-section and decay libraries adequately represent the ELWR fuel and lithium targets.
The MCODE results are treated as reliable with no validation against ELWR operational data.
domain assumption The total lithium-6 loading, not the target geometry, determines tritium production and reactivity penalty.
Paper asserts this in Endnote 16; actual target design is unknown.
domain assumption Single-batch operation is the appropriate upper-bound scenario.
The paper selects single-batch to maximize cycle length and achieve weapon-grade Pu; other operation modes would give lower output.
ad hoc to paper The approximate 5x5-grid, 17x17-assembly core geometry with 10 burnup zones captures full-core behavior.
Model geometry is constructed to match reported inventory and dimensional estimates, not confirmed by design data.
domain assumption Uniform 3.5% enrichment has only minor effects on the main results.
Stated in Endnote 6 without sensitivity analysis.
domain assumption Weapon-grade plutonium can be defined by 90 wt% Pu-239.
Standard threshold used; Endnote 18 notes North Korea reportedly prefers super-grade, so 90% may overstate usability for their weapons.

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Cite this review

Pith. "Pith review of Estimating Potential Tritium and Plutonium Production in North Korea's Experimental Light Water Reactor." pith.science (2026). https://pith.science/paper/2L4O5VYY

@misc{pith2026241211993,
  author       = {Pith},
  title        = {Pith review of: Estimating Potential Tritium and Plutonium Production in North Korea's Experimental Light Water Reactor},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/2L4O5VYY}},
  note         = {Machine review of arXiv:2412.11993}
}

read the original abstract

Our work explores North Korea's 100 MW-th Experimental Light Water Reactor (ELWR) and its potential contributions to the country's nuclear weapons program. Built at the Yongbyon Nuclear Research Center, the ELWR began operations in October 2023 and represents North Korea's first attempts at a light-water reactor using domestically-enriched, ceramic fuel. Our study examines possible configurations for energy, tritium, and tritium-plutonium co-production. Assuming a single-batch core, the ELWR can be used to annually produce 48-82 grams of tritium, which can supply 2-4 new boosted warheads each year, up to a maximum arsenal of 88-150 warheads total. Concurrent production of tritium and weapon-grade plutonium is also possible but requires reprocessing of spent ceramic fuel. These findings underscore how North Korea's nuclear capabilities may be advanced through the ELWR's dual-use potential.

Figures

Figures reproduced from arXiv: 2412.11993 by the authors.

**Figure 1.** North Korean nuclear weapons. In March 2016, North Korea first published photos of a probable nuclear weapon, shown on the left (“the disco ball”); that year, it conducted two nuclear tests, both of which have been considered successful. On September 2, 2017, North Korea published a photo of a two-stage weapon, shown on the right (“the peanut”). The following day, it conducted a large nuclear weapon test with an est… view at source ↗

**Figure 2.** Core configuration used for all full-core depletion calculations. [PITH_FULL_IMAGE:figures/full_fig_p004_2.png] view at source ↗

**Figure 3.** Total tritium production versus lithium loading. [PITH_FULL_IMAGE:figures/full_fig_p006_3.png] view at source ↗

Figures from the paper (2 more)

**Figure 4.** Figure 4: Core reactivity keff vs fuel burnup. We assume that the core reaches its end of life once keff drops below 1.03. The discharge burnup strongly depends on the type of cladding used and the amount of lithium-6 present in the core. All results are from full-core MCODE6 si…

**Figure 5.** Figure 5: Plutonium-239 fraction and residual uranium-235 enrichment versus fuel burnup. [PITH_FULL_IMAGE:figures/full_fig_p008_5.png]

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

12 extracted references · 12 canonical work pages

[1]

exponentially expand

Estimating Potential Tritium and Plutonium Production in North Korea’s Experimental Light Water Reactor Patrick J. Park and Alexander Glaser Program on Science and Global Security, Princeton University Abstract. Our work explores North Korea’s 100 MW-th Experimental Light Water Reactor (EL WR) and its potential contributions to the country’s nuclear weapo...

work page 2023
[5]

Estimating North Korea’s Nuclear Capabilities: Insights From a Study on Tritium Production in a 5MWe Graphite-moderated Reactor,

5Existing analyses have often focused on the 5 MWe graphite-moderated reactor, but tritium production potential of this facility is rather limited; see for example, Sungmin Yang et al., “Estimating North Korea’s Nuclear Capabilities: Insights From a Study on Tritium Production in a 5MWe Graphite-moderated Reactor,” Nuclear Engineering and Technology, 56, ...

work page 2024
[6]

Estimating Plutonium Production in North Korea,

8“Estimating Plutonium Production in North Korea,” Appendix 3B inGlobal Fissile Material Report 2009: A Path to Nuclear Disarmament, International Panel on Fissile Materials, Princeton, NJ, October

work page 2009
[8]

10Xu, 2003, op. cit. We use MCODE Version 1.0 with minor changes in the source code so that MCNP6 tally files can be parsed correctly. Note that there are more recent releases of MCODE (2.2 and 3.0), but we do not need the added functionalities implemented in those versions. 11Scott B. Ludwig, Revision to ORIGEN2, Version 2.2. Oak Ridge National Lab- oratory, May

work page 2003
[12]

the amount of tritium in a reser- voir is typically less than 20 gm,

18North Korea appears to prefer even super-grade plutonium for their weapons. Dur- ing the Stanford team’s 2010 visit to North Korea, Yongbyon Director Ri Hong Sop was quoted as considering fuel with burnup exceeding 3 MWd/kgU as unusable for weapons; this burnup corresponds to plutonium-239 fraction of about 95%. 19The half life of tritium is 12.32 years...

work page 2010
[1993]

16Embedding lithium in the cladding simplifies the analysis, without having to make further assumptions about the target design. While the actual location and distribution of the material are likely to be different, tritium production rates and core reactivity penalties are largely determined by the total lithium loading and respective net neutron absorpt...

work page 2009
[2002]

Croff, A User’s Manual for the ORIGEN2 Computer Code

Allen G. Croff, A User’s Manual for the ORIGEN2 Computer Code. ORNL/TM7175, Oak Ridge National Laboratory, July 1980, Allen G. Croff, ORIGEN2: A Versatile Computer Code for Calculating the Nuclide Compositions and Characteristics of Nuclear Materials, Nuclear Technology, 62 (3), September

work page 1980
[2003]

Explosive Properties of Reactor-grade Plutonium,

14A North Korean centrifuge engineer reported an average product enrichment level of 3.5% and a tails depletion level of 0.27%; see p. 4 in Hecker, 2010, op. cit. 15Weapon designs prefer a plutonium-239 percentage of 90% or more, even though 16 lower grade plutonium is also weapon-usable; see J. Carson Mark, “Explosive Properties of Reactor-grade Plutoniu...

work page 2010

Show all 12 references

[2009]

Modelling Fissile Production in the Experimental Light Water Reactor (EL WR) of DPRK,

9Cecilia Gustavsson, Peter Andersson, Erik Branger, Grant Christopher, David Schmerler, and Hailey Wingo, “Modelling Fissile Production in the Experimental Light Water Reactor (EL WR) of DPRK,” Alva Myrdal Centre for Nuclear Disarmament, Annual Conference, Uppsala University, ...

2024
[2017]

Yongbyon Test Reactor No. 1

4 It has not been clear, however, how North Korea could produce tritium in sufficient quantities to support its nuclear arsenal. 5 In October 2023, observation of hot effluent release in satellite imagery confirmed the operation of the new Experimental Light Water Reactor (EL ...

2023 arXiv
[2023]

3The process of boosting can be summarized as follows: “The high-energy (14 MeV) neutrons liberated in the D-T reaction are used in many fission weapons to achieve what is known as ‘boosting.’ Neutrons from the D-T reaction are introduced at a late stage of the fission chain i...

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[2024]

2“The present situation highlights the importance and necessity of mass-producing tactical nuclear weapons and demands an exponential increase in the country’s nuclear arsenal... [this being] the epochal strategy of the development of nuclear force and national defense for 202...

2023

Pith tools

Reviewed August 11, 2026 · model on record in the stance chip above.

[1] [1]

exponentially expand

Estimating Potential Tritium and Plutonium Production in North Korea’s Experimental Light Water Reactor Patrick J. Park and Alexander Glaser Program on Science and Global Security, Princeton University Abstract. Our work explores North Korea’s 100 MW-th Experimental Light Water Reactor (EL WR) and its potential contributions to the country’s nuclear weapo...

work page 2023

[2] [5]

Estimating North Korea’s Nuclear Capabilities: Insights From a Study on Tritium Production in a 5MWe Graphite-moderated Reactor,

5Existing analyses have often focused on the 5 MWe graphite-moderated reactor, but tritium production potential of this facility is rather limited; see for example, Sungmin Yang et al., “Estimating North Korea’s Nuclear Capabilities: Insights From a Study on Tritium Production in a 5MWe Graphite-moderated Reactor,” Nuclear Engineering and Technology, 56, ...

work page 2024

[3] [6]

Estimating Plutonium Production in North Korea,

8“Estimating Plutonium Production in North Korea,” Appendix 3B inGlobal Fissile Material Report 2009: A Path to Nuclear Disarmament, International Panel on Fissile Materials, Princeton, NJ, October

work page 2009

[4] [8]

10Xu, 2003, op. cit. We use MCODE Version 1.0 with minor changes in the source code so that MCNP6 tally files can be parsed correctly. Note that there are more recent releases of MCODE (2.2 and 3.0), but we do not need the added functionalities implemented in those versions. 11Scott B. Ludwig, Revision to ORIGEN2, Version 2.2. Oak Ridge National Lab- oratory, May

work page 2003

[5] [12]

the amount of tritium in a reser- voir is typically less than 20 gm,

18North Korea appears to prefer even super-grade plutonium for their weapons. Dur- ing the Stanford team’s 2010 visit to North Korea, Yongbyon Director Ri Hong Sop was quoted as considering fuel with burnup exceeding 3 MWd/kgU as unusable for weapons; this burnup corresponds to plutonium-239 fraction of about 95%. 19The half life of tritium is 12.32 years...

work page 2010

[6] [1993]

16Embedding lithium in the cladding simplifies the analysis, without having to make further assumptions about the target design. While the actual location and distribution of the material are likely to be different, tritium production rates and core reactivity penalties are largely determined by the total lithium loading and respective net neutron absorpt...

work page 2009

[7] [2002]

Croff, A User’s Manual for the ORIGEN2 Computer Code

Allen G. Croff, A User’s Manual for the ORIGEN2 Computer Code. ORNL/TM7175, Oak Ridge National Laboratory, July 1980, Allen G. Croff, ORIGEN2: A Versatile Computer Code for Calculating the Nuclide Compositions and Characteristics of Nuclear Materials, Nuclear Technology, 62 (3), September

work page 1980

[8] [2003]

Explosive Properties of Reactor-grade Plutonium,

14A North Korean centrifuge engineer reported an average product enrichment level of 3.5% and a tails depletion level of 0.27%; see p. 4 in Hecker, 2010, op. cit. 15Weapon designs prefer a plutonium-239 percentage of 90% or more, even though 16 lower grade plutonium is also weapon-usable; see J. Carson Mark, “Explosive Properties of Reactor-grade Plutoniu...

work page 2010