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Updates to flow model calculations
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Flow model transfer rates.md

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@@ -108,6 +108,7 @@ g
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\sqrt{M_{Pd}c^2 P_{diss} \tau_A} }{ \epsilon}
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\sqrt{\frac{N_{\mathrm{Pd}}}{N}} .
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\end{aligned}
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\label{eq:g_to_Pdiss}
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\end{equation}
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$$
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@@ -120,7 +121,7 @@ $$
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We can connect $\bar \Upsilon$ to $g$ through:
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$$
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\frac{|\langle \mathrm{Pd}^* | a_z | \mathrm{Pd} \rangle| \sqrt{M_{Pd}c^2}}{\epsilon} = \sqrt{\frac{\bar \Upsilon}{4 \epsilon}} \approx \sqrt{\frac{2.2 \times 10^{-8}}{\times6.75 \times 10^6 \times 1.6\times 10^{-19}\, \rm J}} \approx 142
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\frac{|\langle \mathrm{Pd}^* | a_z | \mathrm{Pd} \rangle| \sqrt{M_{Pd}c^2}}{\epsilon} = \sqrt{\frac{\bar \Upsilon}{\epsilon}} \approx \sqrt{\frac{2.2 \times 10^{-8}}{6.75 \times 10^6 \times 1.6\times 10^{-19}\, \rm J}} \approx 142
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$$
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This gives
@@ -302,7 +303,7 @@ $$
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\hbar \omega_0 \, \Delta n_{00}
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&= \hbar \omega_0
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\left( 2 n_j \,\bar{\Upsilon}_j \, |e^{(O)}|^2 \, n_O \right)^{1/3} \\
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&= 0.12 \, |e^{(O)}|^{2/3} \, (n_j)^{1/3}
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&= 0.075 \, |e^{(O)}|^{2/3} \, (n_j)^{1/3}
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\left( \frac{P_D^{(O)}}{1\,\mathrm{W}} \right)^{1/3}
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\left( \frac{f_O}{1\,\mathrm{MHz}} \right)^{1/6}
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\;\mathrm{eV}
@@ -344,7 +345,7 @@ $$
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~{\rm s}^{-1}
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$$
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This is Weisskopf modified to include a hinderance factor $O_{Pd}$ which we estimate to be 0.01. For $\epsilon \approx 6MeV$ and $A\approx 106$ we have
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This is Weisskopf modified to include a hinderance factor $O_{Pd}$ which we estimate to be 0.01. For $\epsilon \approx 6 \, \rm MeV$ and $A\approx 106$ we have
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$$
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\Gamma_{M2} \sim 3.8 \times 10^8 \, \rm s^{-1}
@@ -374,3 +375,55 @@ $$
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\Gamma_{D_2/(3+1)/^4He \,incoherent} \sim \frac{(5.3\times 10^6)^2}{1.5\times 10^9} \approx 18,700 \, \rm s^{-1}
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$$
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Note that if we don't use the large $g$ approximation and instead use the actual value for $F(g)$ for these parameters then we end up with a rate more like $2,800 \, \rm s^{-1}$.
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## 3+1 vs other products
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If we successfully transfer excitation from The $\rm D_2$ donors to $\rm Pd$ receivers, then the resulting products very sensitively on the composition of the lattice. For transfer to four $\rm Pd$ transitions, we have $\sim 6 \rm \, MeV$ of nuclear energy to dissipate. If this does not go into excess heat then it can go into gamma rays or an alpha particle if there are sufficient number of low Z impurities that can eject alphas preferentially to gammas.
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Because the excitation transfer pathway involves the compact (3+1) state which can decay to produce the standard fusion products. We estimated the rate of (3+1) products compared to other products in the SI according to
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$$
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\frac{\Gamma_{3+1}}{\Gamma_{transfer}} = \frac{1}{2}\frac{\Gamma_{transfer}\gamma_{tunnel}}{\sqrt{\mathcal{V}^2_{3+1/^4He}/h^2 + \gamma_{tunnel}^2}}
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\label{eq:3+1vsothers}
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$$
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Where $h\gamma_{tunnel}\approx 5.95 \, \rm MeV$ is the linewidth (corresponding to $\gamma_{tunnel}\approx 1.4 \times 10^{21} \, \rm s^{-1}$) of the tunnel decay from the (3+1) state into the standard fusion products and $\mathcal{V}_{3+1/^4He}$ it the Dicke enhanced matrix element between the (3+1) state and the $\rm ^4He$ ground state
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$$
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\mathcal{V}_{3+1/^4He} = |\langle \rm ^4He | a_z | {\rm 3+1} \rangle| c \sqrt{\langle P_{\rm ^4He}^2 \rangle}\sqrt{N_{\rm ^4He}}
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$$
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We can rewrite this in terms of dissipated power as we did in Eq. $\ref{eq:g_to_Pdiss}$
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$$
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\mathcal{V}_{3+1/^4He} = |\langle \rm ^4He | a_z | {\rm 3+1} \rangle| \sqrt{M_{^4He}c^2 P_{diss} \tau_A} \, \sqrt{\frac{N_{\mathrm{^4He}}}{N}}
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$$
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Where $ |\langle \rm ^4He | a_z | {\rm 3+1} \rangle| \approx 0.000315$.
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Given that
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$$
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\sqrt{\tau_A} = 10^{-6}\left( \frac{1\,\mathrm{MHz}}{f_A} \right)^{3/4} 10^{-7\times -3/4} \approx 0.178\left( \frac{1\,\mathrm{MHz}}{f_A} \right)^{3/4}
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$$
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and
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$$
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\sqrt{M_{^4He}c^2} = \sqrt{4 \times 1.67\times 10^{-27} \times (3\times 10^8)^2} \approx \sqrt{6\times 10^{-10}} \approx 2.45 \times 10^{-5}
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$$
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then
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$$
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\mathcal{V}_{3+1/^4He} = 1.37\times 10^{-9} \left( \frac{1\,\mathrm{MHz}}{f_A} \right)^{3/4} \sqrt{ \frac{P_{diss}}{1\,\mathrm{W}} } \, \sqrt{\frac{N_{\mathrm{^4He}}}{N}} \, \rm J
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$$
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And
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$$
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\frac{\mathcal{V}_{3+1/^4He}}{h} \approx 2 \times 10^{24} \left( \frac{1\,\mathrm{MHz}}{f_A} \right)^{3/4} \sqrt{ \frac{P_{diss}}{1\,\mathrm{W}} } \, \sqrt{\frac{N_{\mathrm{^4He}}}{N}} \, \rm s^{-1}
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$$
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In the limit that $\mathcal{V}_{3+1/^4He} \gg \gamma_{tunnel}$ then using indirect transfer rate we have
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$$
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\frac{\Gamma_{3+1}}{\Gamma_{transfer}} = \frac{1}{2}\frac{\Gamma_{transfer}\gamma_{tunnel}}{\mathcal{V}^2_{3+1/^4He}/h^2} = \frac{1}{2}\frac{245 \sqrt{\frac{N_{D_2}}{N}} \sqrt{N_{^4 He}} F(g)^4 \rho \,\delta \epsilon \times 1.4\times 10^{21}}{4 \times 10^{48} \left( \frac{1\,\mathrm{MHz}}{f_A} \right)^{3/4} \sqrt{ \frac{P_{diss}}{1\,\mathrm{W}} } \, \frac{N_{\mathrm{^4He}}}{N} }
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$$
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$$
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\approx 8.6\times 10^{-26} \rho \,\delta \epsilon\sqrt{N_{D_2}}\sqrt{\frac{N}{N_{\mathrm{^4He}}}}\left( \frac{f_A}{1\,\mathrm{MHz}} \right)^{3/4} \sqrt{ \frac{1\,\mathrm{W}}{P_{diss}} }F(g)^4
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$$
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For SI parameters we have
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$$
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\frac{\Gamma_{3+1}}{\Gamma_{transfer}} \sim 0.02 F(g)^4
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$$
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Where I multipled and divided by $\sqrt{N}$ and then using $N\sim 10^{18}$ and assumed $N_{\mathrm{^4He}} \sim 1$.

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