Isotope Fusion Explorer — reaction energetics and kinematics

Frame discipline: projectile controls take laboratory energy; cross-section lookup and available kinetic energy report centre-of-mass energy from the invariant-s transformation s = m_a² + m_b² + 2m_b(m_a + T_lab), which is algebraically exact for the stated rest masses. One mass record (ame2020-bare-nistasd512@1) gives bare-nucleus masses — AME2020 atomic masses − Z·m_e + total electron binding B_e(Z) from NIST ASD 5.12 — to Q, threshold, event generation and transport; the frame in use is named on every reported quantity.

Reaction

Projectile isotope

Target isotope

Channel

Projectile energy MeV labStationary target; E_cm, thresholds and two-body partitions use relativistic invariant-s kinematics with the bare-nucleus masses of record ame2020-bare-nistasd512@1. Interface scope: 0–10 MeV.

Loading cross-section data…

Nuclide

Inspect isotope

p–¹¹B alpha source model

α0 branch-fraction modelThe measured model is valid only for E_cm 226.288487578–2002.5399985 keV CM (E_p 247–2186 keV lab); outside it the source is unavailable — never extrapolated and never replaced by the user value. Held-out verdict against Symons 1963: χ² 10.50/3, p 0.0147, a marginal pass that holds only with the pre-declared energy-spread term (without it p = 0.0046).

⁸Be ground branch fractionRequired user assumption; measured value is energy dependent.

Events

Seed

Available only when the selected reaction channel is p + ¹¹B → 3α.

Product transport

Reference frame

Uniform Bz TRange [-100, 100] T (tesla): the uniform field along +z that bends charged products; 0 T is straight-line flight. A value outside the range rejects the transport result only; the other results stay current.

Spherical boundary radius mRange [0.001, 100] m (metres): the sphere about the reaction point at which each boundary crossing is recorded. A value outside the range rejects the transport result only; the other results stay current.

Flight duration sRange [1e-12, 1] s (seconds): the physical flight time followed; with Bz it is also limited so that no charged product turns through more than 6000 rad. A value outside the range rejects the transport result only; the other results stay current.

Geometric detector half-angle deg, +XRange [0, 90]° (degrees): the half-angle of the detector cap about the +X axis; 0° is a point on the axis, 90° the whole +X hemisphere. A value outside the range rejects the transport result only; the other results stay current.

Exact collisionless helix in uniform B; neutral products free stream. Detector acceptance is geometric, with no material or response model.

Reaction energetics

3D nuclide and CM-event explorer

Nucleon positions are a schematic inventory. Product arrows use conserving relativistic selected-event four-momenta in the reaction CM, with normalized display length.

Initializing local 3D renderer…

Left: schematic proton/neutron inventory for the selected nuclide. Right: one conserving selected-channel reaction-CM event. Pointer orbit is visual-only; the equivalent four-vector table follows. Arrow direction and relative momentum magnitude are model-derived; rendered distance and playback time are not transport.

Displayed sampled event none

Normalized event frame 1 / 1

Display rate frames/s

Viewer layers — display only Nucleon inventory CM momentum event Axes/grid

Sequential alpha spectrum

Run the p–¹¹B spectrum sampler to see energy closure and the model spread.

p–¹¹B cross-section reference

Radiation-relevant side channels

Channel	Why it matters	Current lab treatment
¹¹B(p,n)¹¹C	Threshold neutron and radioactive ¹¹C production.	Q value and threshold calculated; no yield model.
¹⁰B impurity reactions	Natural boron contains ¹⁰B; activation/products depend on beam spectrum.	p+¹⁰B energetics only; impurity fraction is not silently assumed.
α-induced reactions	Escaping MeV alphas can produce secondary radiation in structures.	Not calculated; requires material-specific evaluated data and transport.

“Aneutronic” is not “radiation-free.” Device claims require a full energy-dependent neutronics/activation assessment.

Evidence and validity

Nuclear masses

One mass record, ame2020-bare-nistasd512@1, feeds Q, threshold, invariant-s energy, event generation and transport: bare nuclei M_N = M_A − Z·m_e + B_e(Z)/c² from the AME2020 atomic-mass slice, the AME2020 Table A constants (1 u, m_e; CODATA 2018) and the NIST ASD v5.12 total electron binding energies (≤ 0.0004 eV per atom). Electron rest masses cancel in every listed channel, but the binding does not: the neutral-atom (AME/NNDC table) Q differs from the bare-nucleus Q by ΔB_e = ΣB_e(in) − ΣB_e(out) (+447.567 eV for p + ¹¹B → 3α), which is shown beside every Q and is 2.9σ to 275σ of the marginal mass uncertainty across the channels. σ_Q is that AME2020 marginal mass uncertainty only (signed net stoichiometry, zero inter-nuclide covariance); it excludes the inter-nuclide covariance, the constants 1 u and m_e, the binding-energy uncertainty and the isotope dependence of B_e (≤ 0.011 eV). Thresholds are for a bare projectile on a stationary bare target; atomic effects in a solid target (order 0.1–0.4 keV) are not modelled.

Alpha spectrum and 3D event

The sampler enforces both ΣE_α = Q_bare + E_cm (Q_bare = 8.682378 MeV, from the mass record) and Σp⃗_α = 0 in the reaction CM for exported 3D events, with mass-shell residuals checked. It uses sequential decay through ⁸Be, a 3.03 MeV broad level, a truncated Breit–Wigner, and isotropic decay angles. Exclusive measurements show energy-dependent angular/partial-wave structure; therefore this is a structural demonstrator, not evaluated differential product data or device-frame transport.

What is still excluded