[07/08] EVIDENCE CLUSTER · RATE

Low‑energy fusion yield plateau(UC Davis / Berkeley, Thunderbird 2025)

The 2026 plateau result and its thermal-track rival: the exact disagreement our mechanically driven suspension is built to discriminate.

[Illustrative image]

[ITS JOB IN THE DEVICE]

Hit the target. This cluster sets the target enhancement and the discriminating measurement.

Deuterons at 0.25 to 2.5 keV; a 3.02 MeV proton line tells the two readings apart See all 6 lessons ↓

records: 3
years: 2025–2026
papers cited: 3
with a DOI: 2

[3 OF 84 RECORDS · 1986 TO 2026]each bar opens its row

[WHAT WE CARRY INTO THE DEVICE]

What we carry
into the device.

The payoff of this record for the program: 6 design decisions, each tied to what was measured. They feed one input of the device.

[THE SIX DESIGN INPUTS]

Shake it 02 08
Make the field 06
Choose the host 04
Load it, measure it 01 03
Multiply the rate 05
Hit the target 07

Carry into device, in the full document

01

Target deuteron energies of 0.25 to 2.5 keV at contact gaps

This is exactly the range where the reported plateau and the about 3.0 keV effective screening potential were measured, and where our piezo-gap acceleration lands.
02

Load the hydride phase electrochemically or gas-load ex-situ

The Thunderbird record shows loading itself raises yield, so D/Pd loading ratio is a primary device parameter, not a fixed condition.
03

Palladium first, titanium second

Both appear in the Nature Communications record, and the screening analysis covers both; Pd carries the largest reported screening number.
04

Design the experiment to discriminate the two interpretations

Monoenergetic proton lines near 3.02 MeV would indicate discrete field-accelerated deuterons in the bulk, while a flat null would indicate the enhancement does not transfer off the beam platform.
05

Because rates are reported as low even on the beam platform, budget long integration times and background-dominated statistics; the beam record still needed the dual-chamber precision that we must match with neutron time-of-flight plus CR-39.
06

Treat the ion-track question as the central open physics point of the program

A beam-off, mechanically excited hydride suspension is the cleanest available test of whether the plateau is a materials property or a track property.

[THE RECORD]

3 records,
2025 to 2026.

[HOW THIS RECORD WAS COMPILED]

Searched and confirmed 2026-10-21. This cluster is the quantitative center of gravity for the Vantasner device: a 2026 Nature Communications measurement reports D-D fusion yields in metal hydrides that stop falling with beam energy below about 2.5 keV, an enhancement of more than 10^18 over bare-nucleus rates, and an effective screening potential of keV scale. A companion record from the Szczecin group offers a rival interpretation confined to ion tracks, and the 2025 Thunderbird reactor record shows electrochemical loading raising fusion rates in a beam target.

[RAW TABLE] [IN THE FULL DOCUMENT →] Sorted by year. #N is the row number in the repo table.

2025–2026 #1

M.E. Karahadian et al.

UC Davis and Berkeley Lab

Nature Communications 17, 8845 (2026) DOI ↗arXiv ↗Library →

Setup
Dual-chamber platform combining electrochemical deuterium loading with implanted deuteron beam bombardment of the loaded foil

Reported
Pronounced D-D fusion enhancement and a reaction-yield plateau below about 2.5 keV beam energy, contrary to expected exponential suppression; enhancement over 10^18 relative to theoretical bare-nucleus fusion rates; per the paper's analysis an effective screening potential rising to about 3.0 keV for palladium deuteride at 0.25 keV beam energy; the authors state reaction rates are low and frame the result as a materials-driven, reproducible, tunable regime

Materials, loading, excitation, conditions for record 1

Materials
Palladium and titanium hydrides (Pd and Ti foils electrochemically loaded with deuterium)

Loading
Electrochemical D loading of Pd and Ti foils

Excitation
Implanted deuteron beams at sub-keV energies

Conditions
Room-temperature metallic foils, beam energies below 2.5 keV

Who
M.E. Karahadian, M. Colborne, A. Persaud, T. Schenkel, J.N. Munday (UC Davis and Berkeley Lab)

When · venue
Preprint December 2025; journal publication 18 July 2026 · Nature Communications 17, 8845 (2026); DOI 10.1038/s41467-026-74421-1; preprint arXiv:2512.06212

In the library
Karahadian, M.E., Colborne, M., Persaud, A., Schenkel, T.,... (2026)
2025 #3

K.-Y. Chen et al.

University of British Columbia and Lawrence Berkeley National Laboratory

Nature 644, 640-645 (2025) DOI ↗Library →

Setup
The Thunderbird Reactor: a custom benchtop particle accelerator combining plasma immersion ion implantation (PIII) of D+ with an electrochemically loaded palladium target

Reported
Electrochemical loading raises measured D-D fusion rates in the beam target relative to an unloaded target; the reactor is described as capable of detecting the relevant fusion products; the benchtop platform is publicly named the Thunderbird Reactor (UBC news release of 20 August 2025 and press coverage confirmed the name and the same paper)

Materials, loading, excitation, conditions for record 3

Materials
Palladium target; electrolytic loading cell

Loading
Electrochemical loading of the palladium target with deuterium

Excitation
D+ plasma immersion ion implantation onto the loaded target

Conditions
Benchtop, room-temperature target

Who
K.-Y. Chen, J. Maiwald, P.A. Schauer, T. Schenkel, M. Stolar, A.K. Brown, C.P. Berlinguette et al. (University of British Columbia and Lawrence Berkeley National Laboratory)

When · venue
2025 · Nature 644, 640-645 (2025); DOI 10.1038/s41586-025-09042-7

In the library
Chen, K.-Y., Maiwald, J., Schauer, P.A., Schenkel, T.,... (2025)
2026 #2

K. Czerski et al.

University of Szczecin

arXiv:2605.27438, "Thermal deuteron-deuteron fusion in metallic targets" arXiv ↗Library →

Setup
Beam-deuteron experiments on metallic deuterated targets, interpreted with a thermal-track model

Reported
The thermal-track interpretation: D-D fusion in metallic targets proceeds inside beam-generated ion tracks where transient heating and enhanced diffusion dominate; the yield plateau is an effect of the track environment rather than a static screening potential of the bulk material. The group's earlier companion record, "Observation of Thermal Deuteron-Deuteron Fusion in Ion Tracks", arXiv:2409.02112 (2024, revised December 2025), lays out the same mechanism

Materials, loading, excitation, conditions for record 2

Materials
Metallic deuterated targets

Loading
Gas-loaded metallic targets

Excitation
Deuteron beam implantation

Conditions
Low beam energies

Who
K. Czerski, R. Dubey, G. Haridas Das, S. Thulichery, A. Kowalska, N. Targosz-Sleczka, M. Valat (University of Szczecin)

When · venue
2026 (submitted 22 May 2026) · arXiv:2605.27438, "Thermal deuteron-deuteron fusion in metallic targets" (no journal DOI confirmed as of 2026-10-21)

In the library
Czerski, K., Dubey, R., Haridas Das, G., Thulichery, S.,... (2026)

[WHAT WAS AND WAS NOT LOCATED]

Located and confirmed: the Nature Communications 2026 paper (Karahadian et al., DOI 10.1038/s41467-026-74421-1, published 18 July 2026, Nature Communications 17, 8845), including its open-access record, peer-review file, supplementary information and the December 2025 arXiv preprint.
Located and confirmed: the Szczecin thermal-track interpretation, arXiv:2605.27438 (2026) and its 2024 companion arXiv:2409.02112.
Located and confirmed: the Thunderbird record. The name "Thunderbird" belongs to the University of British Columbia's benchtop reactor described in Chen et al., Nature 644, 640 (2025), DOI 10.1038/s41586-025-09042-7. Searches on "Thunderbird fusion 2025", "Thunderbird reactor 2025" and "Thunderbird low energy nuclear reaction" (2026-10-21) all resolve to this UBC paper and its press coverage; no separate Thunderbird reactor program with independent publications was found.
Not located: any independent replication of the sub-keV yield plateau from a third laboratory as of 2026-10-21.

The record table exactly as written in the repo (3 rows × 9 columns; scrolls sideways)

Who	When	Venue / DOI	Setup	Materials	Loading	Excitation	Conditions	Reported outputs
M.E. Karahadian, M. Colborne, A. Persaud, T. Schenkel, J.N. Munday (UC Davis and Berkeley Lab)	Preprint December 2025; journal publication 18 July 2026	Nature Communications 17, 8845 (2026); DOI 10.1038/s41467-026-74421-1; preprint arXiv:2512.06212	Dual-chamber platform combining electrochemical deuterium loading with implanted deuteron beam bombardment of the loaded foil	Palladium and titanium hydrides (Pd and Ti foils electrochemically loaded with deuterium)	Electrochemical D loading of Pd and Ti foils	Implanted deuteron beams at sub-keV energies	Room-temperature metallic foils, beam energies below 2.5 keV	Pronounced D-D fusion enhancement and a reaction-yield plateau below about 2.5 keV beam energy, contrary to expected exponential suppression; enhancement over 10^18 relative to theoretical bare-nucleus fusion rates; per the paper's analysis an effective screening potential rising to about 3.0 keV for palladium deuteride at 0.25 keV beam energy; the authors state reaction rates are low and frame the result as a materials-driven, reproducible, tunable regime
K. Czerski, R. Dubey, G. Haridas Das, S. Thulichery, A. Kowalska, N. Targosz-Sleczka, M. Valat (University of Szczecin)	2026 (submitted 22 May 2026)	arXiv:2605.27438, "Thermal deuteron-deuteron fusion in metallic targets" (no journal DOI confirmed as of 2026-10-21)	Beam-deuteron experiments on metallic deuterated targets, interpreted with a thermal-track model	Metallic deuterated targets	Gas-loaded metallic targets	Deuteron beam implantation	Low beam energies	The thermal-track interpretation: D-D fusion in metallic targets proceeds inside beam-generated ion tracks where transient heating and enhanced diffusion dominate; the yield plateau is an effect of the track environment rather than a static screening potential of the bulk material. The group's earlier companion record, "Observation of Thermal Deuteron-Deuteron Fusion in Ion Tracks", arXiv:2409.02112 (2024, revised December 2025), lays out the same mechanism
K.-Y. Chen, J. Maiwald, P.A. Schauer, T. Schenkel, M. Stolar, A.K. Brown, C.P. Berlinguette et al. (University of British Columbia and Lawrence Berkeley National Laboratory)	2025	Nature 644, 640-645 (2025); DOI 10.1038/s41586-025-09042-7	The Thunderbird Reactor: a custom benchtop particle accelerator combining plasma immersion ion implantation (PIII) of D+ with an electrochemically loaded palladium target	Palladium target; electrolytic loading cell	Electrochemical loading of the palladium target with deuterium	D+ plasma immersion ion implantation onto the loaded target	Benchtop, room-temperature target	Electrochemical loading raises measured D-D fusion rates in the beam target relative to an unloaded target; the reactor is described as capable of detecting the relevant fusion products; the benchtop platform is publicly named the Thunderbird Reactor (UBC news release of 20 August 2025 and press coverage confirmed the name and the same paper)

[THE STORY OF THE RECORD]

How this line of work developed.

The cluster's own narrative, unedited. Read it in the document →

[TERMS IN THIS RECORD]

Deuterium
Deuteron
D-D fusion
Metal hydride
Deuteride
Piezoelectric
Screening potential
Yield plateau

Full glossary →

The Karahadian platform is the closest public analogue to a field-accelerated deuteron crossing a metal hydride: deuterons are pushed into electrochemically loaded Pd or Ti at beam energies from the sub-keV range upward, and the measured yield refuses to follow the exponential Gamow fall, forming a plateau below about 2.5 keV. The paper's analysis converts that plateau into an effective screening potential of keV scale, about 3.0 keV for palladium deuteride at 0.25 keV beam energy, and into a total enhancement exceeding 10^18 over bare-nucleus rates. That number is the load-bearing wall of the Vantasner concept: if an enhancement of that class applies to deuterons accelerated by piezoelectric contact fields (0.1 to 1 keV across nanometer gaps), fusion events in our suspension become observable; if it applies only inside beam-generated ion tracks, as the Szczecin thermal-track record argues, a mechanically excited hydride stays silent. The Thunderbird record adds the loading axis: in the 2025 Nature paper, electrochemical loading of the palladium target raises the fusion rate under identical beam conditions, showing that deuteron density in the metal is itself a control knob on yield. Our device runs the same three variables (deuteron energy from contact fields, deuteron density from hydride loading, and materials environment from the hydride lattice) and measures which of the two competing pictures survives when the beam is removed.

[THE PAPERS]

3 papers
behind it.

2025

Chen, K.-Y., Maiwald, J., Schauer, P.A., Schenkel, T., Stolar, M., Brown, A.K., Berlinguette, C.P., and co-workers

Electrochemical loading enhances deuterium fusion rates in a metal target
(the Thunderbird reactor), Nature 644, 640-645. DOI 10.1038/s41586-025-09042-7.

DOI ↗arXivPDF Library card →

Also in 03 Excess-heat programs
2026

Czerski, K., Dubey, R., Haridas Das, G., Thulichery, S., Kowalska, A., Targosz-Sleczka, N., Valat, M.

Thermal deuteron-deuteron fusion in metallic targets
(the thermal-track interpretation; companion preprint arXiv:2409.02112, 2024), arXiv:2605.27438 (no journal DOI as of 2026-10-21).

DOIarXiv ↗PDF Library card →
2026

Karahadian, M.E., Colborne, M., Persaud, A., Schenkel, T., Munday, J.N., and co-workers

Enhanced nuclear fusion in the sub-keV energy regime
(the sub-keV yield plateau; preprint arXiv:2512.06212, December 2025), Nature Communications 17, 8845. DOI 10.1038/s41467-026-74421-1.

DOI ↗arXiv ↗PDF Library card →