# Cross-sections measurements of α-particles induced reactions on natural Eu target for the production of theranostic Tb radioisotopes

Michele Colucci, E Nigron, F Haddad, F Groppi, S Manenti

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Michele Colucci, E Nigron, F Haddad, F Groppi, S Manenti. Cross-sections measurements of α-particles induced reactions on natural Eu target for the production of theranostic Tb radioisotopes. 16th Nuclear Data (ND) for science and technology conference, Jun 2025, Madrid, Spain. hal-05163653

HAL Id: hal-05163653

https://hal.science/hal-05163653v1

Submitted on 15 Jul 2025

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Distributed under a Creative Commons Attribution 4.0 International License
Cross-sections measurements of α-particles
induced reactions on natural Eu target for the
production of theranostic Tb radioisotopes

M. Colucci, E. Nigron, F. Haddad, F. Groppi, S. Manenti

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# THE SWISS ARMY KNIFE OF NUCLEAR MEDICINE

Terbium offers a unique set of radioisotopes for both diagnostic and therapeutic applications.

## Key isotopes:

* ¹⁴⁹Tb: Targeted Alpha Therapy (TAT) and PET imaging.

* ¹⁵²Tb: PET imaging for extended imaging times.

* ¹⁵⁵Tb: SPECT imaging and Auger electrons-based therapy.

* ¹⁶¹Tb: β⁻ therapy with added Auger electrons benefits.

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# THE SWISS ARMY KNIFE OF NUCLEAR MEDICINE

Terbium offers a unique set of radioisotopes for both diagnostic and therapeutic applications.

## Key isotopes:

* ¹⁴⁹Tb: Targeted Alpha Therapy (TAT) and PET imaging.

* ¹⁵²Tb: PET imaging for extended imaging times.

* ¹⁵⁵Tb: SPECT imaging and Auger electrons-based therapy.

* ¹⁶¹Tb: β⁻ therapy with added Auger electrons benefits.

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# OPTIMIZATION OF TB PRODUCTION AT LASA

**Objective:** Compare different production routes, determining the optimization parameters for each of them and determine the most suitable one for each terbium radioisotope.

**Key Experimental Activities:**

1. Irradiations conducted at **GIP ARRONAX** cyclotron (France).

2. High-resolution gamma spectrometry using HPGe detectors at **LASA lab** (Milan) and GIP ARRONAX.

3. Radiochemical separation of terbium from gadolinium targets to establish a purification protocol.

<table><thead><tr><td>Target</td><td>Form</td><td>Beam</td><td>Energy range</td></tr></thead><tbody><tr><td>natEu</td><td>Eu<sub>2</sub>O<sub>3</sub></td><td>α</td><td>20-65 MeV</td></tr><tr><td>natGd</td><td>metal</td><td>α</td><td>30-65 MeV</td></tr><tr><td><sup>159</sup>Tb</td><td>metal</td><td>p</td><td>35-63 MeV</td></tr><tr><td>natDy</td><td>metal</td><td>p</td><td>35-57 MeV</td></tr><tr><td>natDy</td><td>metal</td><td>d</td><td>12-32 MeV</td></tr></tbody></table>

REMiX

INFN CSN5 project
(2021-2023)

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SPES<sup>TM</sup>MED

INFN CSN3 project
(2024, 2025-2028)
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natEu(α,x) – target

**Target realization**

* Eu₂O₃ nanopowder (8-40 nm)

* Blade coating preparation of thin targets using 3% Na-CMC polymer

* Collaboration with Chemistry dept. of the POLIMI

**Target characterization**

* SEM analysis to verify the uniformity

* ICP-OES to determine the mass of Eu in the target

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natEu($\alpha$,x) – irradiation setup

<figure><img src="image_20.png" /><figcaption>Example of stack – Irradiation setup</figcaption></figure>

* Four irradiations with overlapped energy range in a period of different months

* Irradiation duration: 1 h

* Monitor reactions: $^{27}$Al($\alpha$,x)$^{24}$Na, natCu($\alpha$,x)$^{66,68}$Ga

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natEu(α,x) – produced radionuclides

<table><thead><tr><th>Element</th><th>α</th><th>x</th></tr></thead><tbody><tr><td>Eu</td><td>153</td><td>Eu</td></tr><tr><td>Eu</td><td>154</td><td>Eu</td></tr><tr><td>Eu</td><td>155</td><td>Eu</td></tr><tr><td>Eu</td><td>156</td><td>Eu</td></tr><tr><td>Eu</td><td>157</td><td>Eu</td></tr><tr><td>Eu</td><td>158</td><td>Eu</td></tr><tr><td>Eu</td><td>159</td><td>Eu</td></tr><tr><td>Eu</td><td>160</td><td>Eu</td></tr><tr><td>Eu</td><td>161</td><td>Eu</td></tr><tr><td>Eu</td><td>162</td><td>Eu</td></tr><tr><td>Eu</td><td>163</td><td>Eu</td></tr><tr><td>Eu</td><td>164</td><td>Eu</td></tr><tr><td>Eu</td><td>165</td><td>Eu</td></tr><tr><td>Eu</td><td>166</td><td>Eu</td></tr><tr><td>Eu</td><td>167</td><td>Eu</td></tr><tr><td>Eu</td><td>168</td><td>Eu</td></tr><tr><td>Eu</td><td>169</td><td>Eu</td></tr><tr><td>Eu</td><td>170</td><td>Eu</td></tr><tr><td>Eu</td><td>171</td><td>Eu</td></tr><tr><td>Eu</td><td>172</td><td>Eu</td></tr><tr><td>Eu</td><td>173</td><td>Eu</td></tr><tr><td>Eu</td><td>174</td><td>Eu</td></tr><tr><td>Eu</td><td>175</td><td>Eu</td></tr><tr><td>Eu</td><td>176</td><td>Eu</td></tr><tr><td>Eu</td><td>177</td><td>Eu</td></tr><tr><td>Eu</td><td>178</td><td>Eu</td></tr><tr><td>Eu</td><td>179</td><td>Eu</td></tr><tr><td>Eu</td><td>180</td><td>Eu</td></tr><tr><td>Eu</td><td>181</td><td>Eu</td></tr><tr><td>Eu</td><td>182</td><td>Eu</td></tr><tr><td>Eu</td><td>183</td><td>Eu</td></tr><tr><td>Eu</td><td>184</td><td>Eu</td></tr><tr><td>Eu</td><td>185</td><td>Eu</td></tr><tr><td>Eu</td><td>186</td><td>Eu</td></tr><tr><td>Eu</td><td>187</td><td>Eu</td></tr><tr><td>Eu</td><td>188</td><td>Eu</td></tr><tr><td>Eu</td><td>189</td><td>Eu</td></tr><tr><td>Eu</td><td>190</td><td>Eu</td></tr><tr><td>Eu</td><td>191</td><td>Eu</td></tr><tr><td>Eu</td><td>192</td><td>Eu</td></tr><tr><td>Eu</td><td>193</td><td>Eu</td></tr><tr><td>Eu</td><td>194</td><td>Eu</td></tr><tr><td>Eu</td><td>195</td><td>Eu</td></tr><tr><td>Eu</td><td>196</td><td>Eu</td></tr><tr><td>Eu</td><td>197</td><td>Eu</td></tr><tr><td>Eu</td><td>198</td><td>Eu</td></tr><tr><td>Eu</td><td>199</td><td>Eu</td></tr><tr><td>Eu</td><td>200</td><td>Eu</td></tr><tr><td>Eu</td><td>201</td><td>Eu</td></tr><tr><td>Eu</td><td>202</td><td>Eu</td></tr><tr><td>Eu</td><td>203</td><td>Eu</td></tr><tr><td>Eu</td><td>204</td><td>Eu</td></tr><tr><td>Eu</td><td>205</td><td>Eu</td></tr><tr><td>Eu</td><td>206</td><td>Eu</td></tr><tr><td>Eu</td><td>207</td><td>Eu</td></tr><tr><td>Eu</td><td>208</td><td>Eu</td></tr><tr><td>Eu</td><td>209</td><td>Eu</td></tr><tr><td>Eu</td><td>210</td><td>Eu</td></tr><tr><td>Eu</td><td>211</td><td>Eu</td></tr><tr><td>Eu</td><td>212</td><td>Eu</td></tr><tr><td>Eu</td><td>213</td><td>Eu</td></tr><tr><td>Eu</td><td>214</td><td>Eu</td></tr><tr><td>Eu</td><td>215</td><td>Eu</td></tr><tr><td>Eu</td><td>216</td><td>Eu</td></tr><tr><td>Eu</td><td>217</td><td>Eu</td></tr><tr><td>Eu</td><td>218</td><td>Eu</td></tr><tr><td>Eu</td><td>219</td><td>Eu</td></tr><tr><td>Eu</td><td>220</td><td>Eu</td></tr><tr><td>Eu</td><td>221</td><td>Eu</td></tr><tr><td>Eu</td><td>222</td><td>Eu</td></tr><tr><td>Eu</td><td>223</td><td>Eu</td></tr><tr><td>Eu</td><td>224</td><td>Eu</td></tr><tr><td>Eu</td><td>225</td><td>Eu</td></tr><tr><td>Eu</td><td>226</td><td>Eu</td></tr><tr><td>Eu</td><td>227</td><td>Eu</td></tr><tr><td>Eu</td><td>228</td><td>Eu</td></tr><tr><td>Eu</td><td>229</td><td>Eu</td></tr><tr><td>Eu</td><td>230</td><td>Eu</td></tr><tr><td>Eu</td><td>231</td><td>Eu</td></tr><tr><td>Eu</td><td>232</td><td>Eu</td></tr><tr><td>Eu</td><td>233</td><td>Eu</td></tr><tr><td>Eu</td><td>234</td><td>Eu</td></tr><tr><td>Eu</td><td>235</td><td>Eu</td></tr><tr><td>Eu</td><td>236</td><td>Eu</td></tr><tr><td>Eu</td><td>237</td><td>Eu</td></tr><tr><td>Eu</td><td>238</td><td>Eu</td></tr><tr><td>Eu</td><td>239</td><td>Eu</td></tr><tr><td>Eu</td><td>240</td><td>Eu</td></tr><tr><td>Eu</td><td>241</td><td>Eu</td></tr><tr><td>Eu</td><td>242</td><td>Eu</td></tr><tr><td>Eu</td><td>243</td><td>Eu</td></tr><tr><td>Eu</td><td>244</td><td>Eu</td></tr><tr><td>Eu</td><td>245</td><td>Eu</td></tr><tr><td>Eu</td><td>246</td><td>Eu</td></tr><tr><td>Eu</td><td>247</td><td>Eu</td></tr><tr><td>Eu</td><td>248</td><td>Eu</td></tr><tr><td>Eu</td><td>249</td><td>Eu</td></tr><tr><td>Eu</td><td>250</td><td>Eu</td></tr><tr><td>Eu</td><td>251</td><td>Eu</td></tr><tr><td>Eu</td><td>252</td><td>Eu</td></tr><tr><td>Eu</td><td>253</td><td>Eu</td></tr><tr><td>Eu</td><td>254</td><td>Eu</td></tr><tr><td>Eu</td><td>255</td><td>Eu</td></tr><tr><td>Eu</td><td>256</td><td>Eu</td></tr><tr><td>Eu</td><td>257</td><td>Eu</td></tr><tr><td>Eu</td><td>258</td><td>Eu</td></tr><tr><td>Eu</td><td>259</td><td>Eu</td></tr><tr><td>Eu</td><td>260</td><td>Eu</td></tr><tr><td>Eu</td><td>261</td><td>Eu</td></tr><tr><td>Eu</td><td>262</td><td>Eu</td></tr><tr><td>Eu</td><td>263</td><td>Eu</td></tr><tr><td>Eu</td><td>264</td><td>Eu</td></tr><tr><td>Eu</td><td>265</td><td>Eu</td></tr><tr><td>Eu</td><td>266</td><td>Eu</td></tr><tr><td>Eu</td><td>267</td><td>Eu</td></tr><tr><td>Eu</td><td>268</td><td>Eu</td></tr><tr><td>Eu</td><td>269</td><td>Eu</td></tr><tr><td>Eu</td><td>270</td><td>Eu</td></tr><tr><td>Eu</td><td>271</td><td>Eu</td></tr><tr><td>Eu</td><td>272</td><td>Eu</td></tr><tr><td>Eu</td><td>273</td><td>Eu</td></tr><tr><td>Eu</td><td>274</td><td>Eu</td></tr><tr><td>Eu</td><td>275</td><td>Eu</td></tr><tr><td>Eu</td><td>276</td><td>Eu</td></tr><tr><td>Eu</td><td>277</td><td>Eu</td></tr><tr><td>Eu</td><td>278</td><td>Eu</td></tr><tr><td>Eu</td><td>279</td><td>Eu</td></tr><tr><td>Eu</td><td>280</td><td>Eu</td></tr><tr><td>Eu</td><td>281</td><td>Eu</td></tr><tr><td>Eu</td><td>282</td><td>Eu</td></tr><tr><td>Eu</td><td>283</td><td>Eu</td></tr><tr><td>Eu</td><td>284</td><td>Eu</td></tr><tr><td>Eu</td><td>285</td><td>Eu</td></tr><tr><td>Eu</td><td>286</td><td>Eu</td></tr><tr><td>Eu</td><td>287</td><td>Eu</td></tr><tr><td>Eu</td><td>288</td><td>Eu</td></tr><tr><td>Eu</td><td>289</td><td>Eu</td></tr><tr><td>Eu</td><td>290</td><td>Eu</td></tr><tr><td>Eu</td><td>291</td><td>Eu</td></tr><tr><td>Eu</td><td>292</td><td>Eu</td></tr><tr><td>Eu</td><td>293</td><td>Eu</td></tr><tr><td>Eu</td><td>294</td><td>Eu</td></tr><tr><td>Eu</td><td>295</td><td>Eu</td></tr><tr><td>Eu</td><td>296</td><td>Eu</td></tr><tr><td>Eu</td><td>297</td><td>Eu</td></tr><tr><td>Eu</td><td>298</td><td>Eu</td></tr><tr><td>Eu</td><td>299</td><td>Eu</td></tr><tr><td>Eu</td><td>300</td><td>Eu</td></tr><tr><td>Eu</td><td>301</td><td>Eu</td></tr><tr><td>Eu</td><td>302</td><td>Eu</td></tr><tr><td>Eu</td><td>303</td><td>Eu</td></tr><tr><td>Eu</td><td>304</td><td>Eu</td></tr><tr><td>Eu</td><td>305</td><td>Eu</td></tr><tr><td>Eu</td><td>306</td><td>Eu</td></tr><tr><td>Eu</td><td>307</td><td>Eu</td></tr><tr><td>Eu</td><td>308</td><td>Eu</td></tr><tr><td>Eu</td><td>309</td><td>Eu</td></tr><tr><td>Eu</td><td>310</td><td>Eu</td></tr><tr><td>Eu</td><td>311</td><td>Eu</td></tr><tr><td>Eu</td><td>312</td><td>Eu</td></tr><tr><td>Eu</td><td>313</td><td>Eu</td></tr><tr><td>Eu</td><td>314</td><td>Eu</td></tr><tr><td>Eu</td><td>315</td><td>Eu</td></tr><tr><td>Eu</td><td>316</td><td>Eu</td></tr><tr><td>Eu</td><td>317</td><td>Eu</td></tr><tr><td>Eu</td><td>318</td><td>Eu</td></tr><tr><td>Eu</td><td>319</td><td>Eu</td></tr><tr><td>Eu</td><td>320</td><td>Eu</td></tr><tr><td>Eu</td><td>321</td><td>Eu</td></tr><tr><td>Eu</td><td>322</td><td>Eu</td></tr><tr><td>Eu</td><td>323</td><td>Eu</td></tr><tr><td>Eu</td><td>324</td><td>Eu</td></tr><tr><td>Eu</td><td>325</td><td>Eu</td></tr><tr><td>Eu</td><td>326</td><td>Eu</td></tr><tr><td>Eu</td><td>327</td><td>Eu</td></tr><tr><td>Eu</td><td>328</td><td>Eu</td></tr><tr><td>Eu</td><td>329</td><td>Eu</td></tr><tr><td>Eu</td><td>330</td><td>Eu</td></tr><tr><td>Eu</td><td>331</td><td>Eu</td></tr><tr><td>Eu</td><td>332</td><td>Eu</td></tr><tr><td>Eu</td><td>333</td><td>Eu</td></tr><tr><td>Eu</td><td>334</td><td>Eu</td></tr><tr><td>Eu</td><td>335</td><td>Eu</td></tr><tr><td>Eu</td><td>336</td><td>Eu</td></tr><tr><td>Eu</td><td>337</td><td>Eu</td></tr><tr><td>Eu</td><td>338</td><td>Eu</td></tr><tr><td>Eu</td><td>339</td><td>Eu</td></tr><tr><td>Eu</td><td>340</td><td>Eu</td></tr><tr><td>Eu</td><td>341</td><td>Eu</td></tr><tr><td>Eu</td><td>342</td><td>Eu</td></tr><tr><td>Eu</td><td>343</td><td>Eu</td></tr><tr><td>Eu</td><td>344</td><td>Eu</td></tr><tr><td>Eu</td><td>345</td><td>Eu</td></tr><tr><td>Eu</td><td>346</td><td>Eu</td></tr><tr><td>Eu</td><td>347</td><td>Eu</td></tr><tr><td>Eu</td><td>348</td><td>Eu</td></tr><tr><td>Eu</td><td>349</td><td>Eu</td></tr><tr><td>Eu</td><td>350</td><td>Eu</td></tr><tr><td>Eu</td><td>351</td><td>Eu</td></tr><tr><td>Eu</td><td>352</td><td>Eu</td></tr><tr><td>Eu</td><td>353</td><td>Eu</td></tr><tr><td>Eu</td><td>354</td><td>Eu</td></tr><tr><td>Eu</td><td>355</td><td>Eu</td></tr><tr><td>Eu</td><td>356</td><td>Eu</td></tr><tr><td>Eu</td><td>357</td><td>Eu</td></tr><tr><td>Eu</td><td>358</td><td>Eu</td></tr><tr><td>Eu</td><td>359</td><td>Eu</td></tr><tr><td>Eu</td><td>360</td><td>Eu</td></tr><tr><td>Eu</td><td>361</td><td>Eu</td></tr><tr><td>Eu</td><td>362</td><td>Eu</td></tr><tr><td>Eu</td><td>363</td><td>Eu</td></tr><tr><td>Eu</td><td>364</td><td>Eu</td></tr><tr><td>Eu</td><td>365</td><td>Eu</td></tr><tr><td>Eu</td><td>366</td><td>Eu</td></tr><tr><td>Eu</td><td>367</td><td>Eu</td></tr><tr><td>Eu</td><td>368</td><td>Eu</td></tr><tr><td>Eu</td><td>369</td><td>Eu</td></tr><tr><td>Eu</td><td>370</td><td>Eu</td></tr><tr><td>Eu</td><td>371</td><td>Eu</td></tr><tr><td>Eu</td><td>372</td><td>Eu</td></tr><tr><td>Eu</td><td>373</td><td>Eu</td></tr><tr><td>Eu</td><td>374</td><td>Eu</td></tr><tr><td>Eu</td><td>375</td><td>Eu</td></tr><tr><td>Eu</td><td>376</td><td>Eu</td></tr><tr><td>Eu</td><td>377</td><td>Eu</td></tr><tr><td>Eu</td><td>378</td><td>Eu</td></tr><tr><td>Eu</td><td>379</td><td>Eu</td></tr><tr><td>Eu</td><td>380</td><td>Eu</td></tr><tr><td>Eu</td><td>381</td><td>Eu</td></tr><tr><td>Eu</td><td>382</td><td>Eu</td></tr><tr><td>Eu</td><td>383</td><td>Eu</t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td>Eu</td><td>500</td><td>Eu</td></tr><tr><td>Eu</td><td>501</td><td>Eu</td></tr><tr><td>Eu</td><td>502</td><td>Eu</td></tr><tr><td>Eu</td><td>503</td><td>Eu</td></tr><tr><td>Eu</td><td>504</td><td>Eu</td></tr><tr><td>Eu</td><td>505</td><td>Eu</td></tr><tr><td>Eu</td><td>506</td><td>Eu</td></tr><tr><td>Eu</td><td>507</td><td>Eu</td></tr><tr><td>Eu</td><td>508</td><td>Eu</td></tr><tr><td>Eu</td><td>509</td><td>Eu</td></tr><tr><td>Eu</td><td>510</td><td>Eu</td></tr><tr><td>Eu</td><td>511</td><td>Eu</td></tr><tr><td>Eu</td><td>512</td><td>Eu</td></tr><tr><td>Eu</td><td>513</td><td>Eu</td></tr><tr><td>Eu</td><td>514</td><td>Eu</td></tr><tr><td>Eu</td><td>515</td><td>Eu</td></tr><tr><td>Eu</td><td>516</td><td>Eu</td></tr><tr><td>Eu</td><td>517</td><td>Eu</td></tr><tr><td>Eu</td><td>518</td><td>Eu</td></tr><tr><td>Eu</td><td>519</td><td>Eu</td></tr><tr><td>Eu</td><td>520</td><td>Eu</td></tr><tr><td>Eu</td><td>521</td><td>Eu</td></tr><tr><td>Eu</td><td>522</td><td>Eu</td></tr></tbody></table>

47,8 %

52,2 %
<figure><img src="image_25.png" /></figure>

natEu(α,x) – produced radionuclides

<figure><img src="image_26.png" /></figure>
<figure><img src="image_27.png" /></figure>

# natEu(α,x) – results

## NOTE

In all the graphs we reported:

* Experimental results of this work

* Simulations performed with default options using TALYS 1.96 and TALYS 2.0 (Koning et al. 2023)

* Results of the interpolation* and combination** of the results of Moiseeva et al. (2021) and Kormazeva et al. (2025) that measured the cross-sections of production of Tb isotopes on enriched targets of ¹⁵¹Eu and ¹⁵³Eu, respectively.

<figure><img src="image_28.png" /></figure>

<footnote>* Cubic spline; ** $\sigma_{nat} = 0.522 \cdot \sigma_{153}^{inter} + 0.478 \cdot \sigma_{151}^{inter}$</footnote>
natEu(α,x) – ¹⁴⁹Tb

<table><thead><tr><td>Decay mode</td><td>T<sub>1/2</sub></td><td>E<sub>γ</sub> [keV]</td><td>I<sub>γ</sub> [%]</td><td>Contributing reactions</td><td>E<sub>th</sub> [MeV]</td></tr></thead><tbody><tr><td>e.c., β+ 83.3%<br>α 16.7%</td><td>4.118 h</td><td>352.242</td><td>29.87</td><td><sup>151</sup>Eu(α,6n)<br><sup>153</sup>Eu(α,8n)</td><td>50.1<br>65.2</td></tr></tbody></table>

<figure><img src="image_29.png" /></figure>

<figure><img src="image_30.png" /></figure>
natEu(α,x) – 150Tb

<table><thead><tr><td>Decay mode</td><td>T<sub>1/2</sub></td><td>E<sub>γ</sub> [keV]</td><td>I<sub>γ</sub> [%]</td><td>Contributing reactions</td><td>E<sub>th</sub> [MeV]</td></tr></thead><tbody><tr><td>e.c., β+ 100 %<br>α 0.0007%</td><td>3.48 h</td><td>638.050 16</td><td>29.8 7</td><td><sup>151</sup>Eu(α,6n)<br><sup>153</sup>Eu(α,8n)</td><td>50.1<br>65.2</td></tr></tbody></table>

<figure><img src="image_31.png" /></figure>

<figure><img src="image_32.png" /></figure>
<figure><img src="image_33.png" /></figure>

natEu(α,x) – ¹⁵¹Tb

<table><thead><tr><th>Decay mode</th><th>T<sub>1/2</sub></th><th>E<sub>γ</sub> [keV]</th><th>I<sub>γ</sub> [%]</th><th>Contributing reactions</th><th>E<sub>th</sub> [MeV]</th></tr></thead><tbody><tr><td>e.c, β+ 99,9905%</td><td rowspan="6">17.609 h</td><td>251.863 10*</td><td>7.7 3</td><td><sup>151</sup>Eu(α,4n)</td><td>33.5</td></tr><tr><td rowspan="5">α 0.0095%</td><td>252.3 5*</td><td>0.62 14</td><td><sup>153</sup>Eu(α,6n)</td><td>48.6</td></tr><tr><td>252.4 5*</td><td>10.4 4</td><td></td><td></td></tr><tr><td>287.357 1</td><td>28.3 12</td><td></td><td></td></tr><tr><td>616.561 15</td><td>0.062 14</td><td></td><td></td></tr><tr><td>731.2 5*</td><td>0.34 9</td><td></td><td></td></tr><tr><td></td><td>731.227 11*</td><td>26.3 11</td><td></td><td></td><td></td></tr></tbody></table>

<figure><img src="image_34.png" /></figure>

<footnote>* Intensities were summed, efficiency determined in the mass centre of the peak</footnote>
natEu(α,x) – ¹⁵²Tb

<table><thead><tr><td>Decay mode</td><td>T<sub>1/2</sub></td><td>E<sub>γ</sub> [keV]</td><td>I<sub>γ</sub> [%]</td><td>Contributing reactions</td><td>E<sub>th</sub> [MeV]</td></tr></thead><tbody><tr><td>e.c., β+ 100 %</td><td>17.5 h</td><td>411.1165 13<br>764.89 7</td><td>3.6 1<br>2.74 7</td><td><sup>151</sup>Eu(α,3n)<br><sup>153</sup>Eu(α,5n)</td><td>26.2<br>41.1</td></tr></tbody></table>

<figure><img src="image_35.png" /></figure>

<figure><img src="image_36.png" /></figure>
natEu(α,x) – ¹⁵³Tb

<table><thead><tr><td>Decay mode</td><td>T<sub>1/2</sub></td><td>E<sub>γ</sub> [keV]</td><td>I<sub>γ</sub> [%]</td><td>Contributing reactions</td><td>E<sub>th</sub> [MeV]</td></tr></thead><tbody><tr><td>e.c., β+ 100 %</td><td>2.34 d</td><td>212.002</td><td>28.5 19</td><td><sup>151</sup>Eu(α,2n) <br> <sup>153</sup>Eu(α,4n)</td><td>17.4 <br> 32.5</td></tr></tbody></table>

<figure><img src="image_37.png" /></figure>

<figure><img src="image_38.png" /></figure>
natEu(α,x) – ¹⁵⁵Tb

<table><thead><tr><th>Decay mode</th><th>T<sub>1/2</sub></th><th>E<sub>γ</sub> [keV]</th><th>I<sub>γ</sub> [%]</th><th>Contributing reactions</th><th>E<sub>th</sub> [MeV]</th></tr></thead><tbody><tr><td>e.c. 100 %</td><td>5.32 d</td><td>105.318 3</td><td>25.1 13</td><td><sup>151</sup>Eu(α,γ)</td><td>1.0</td></tr><tr><td></td><td></td><td></td><td></td><td><sup>153</sup>Eu(α,2n)</td><td>16.1</td></tr></tbody></table>

<figure><img src="image_39.png" /></figure>

<figure><img src="image_40.png" /></figure>
natEu(α,x) – 156gTb

<table><thead><tr><td>Decay mode</td><td>T<sub>1/2</sub></td><td>E<sub>γ</sub> [keV]</td><td>I<sub>γ</sub> [%]</td><td>Contributing reactions</td><td>E<sub>th</sub> [MeV]</td></tr></thead><tbody><tr><td>e.c., β+ 100 %</td><td>5.35 d</td><td>534.29 6<br>1065.11 15</td><td>67 6<br>10.8 10</td><td><sup>153</sup>Eu(α,n)<br><sup>156m1</sup>Tb (IT)<br><sup>156m2</sup>Tb (IT)</td><td>9.1</td></tr></tbody></table>

<figure><img src="image_41.png" /></figure>

<figure><img src="image_42.png" /></figure>
<figure><img src="image_43.png" /></figure>

<figure><img src="image_44.png" /></figure>

Which isotope of Tb was missing?

<figure><img src="image_45.png" /></figure>
natEu(α,x) – 154m1,m2Tb

¹⁵⁴Tb present two isomers whose mass differences with the ground state is unknown. No gamma emissions seems to be associated with IT.

<table><thead><tr><th>Isomer</th><th>Decay mode</th><th>T<sub>1/2</sub></th><th>E<sub>γ</sub> [keV]</th><th>I<sub>γ</sub> [%]</th><th>Contributing reactions</th><th>E<sub>th</sub> [MeV]</th></tr></thead><tbody><tr><td rowspan="3">154m<sup>2</sup>Tb</td><td rowspan="3">e.c., β+ 98.2 %<br>IT 1.8%</td><td rowspan="3">22.7 h</td><td>346.70 4*</td><td>69.7</td><td><sup>151</sup>Eu(α,n)</td><td>10.3</td></tr><tr><td>722.5 1*</td><td>1.14</td><td><sup>153</sup>Eu(α,3n)</td><td>25.5</td></tr><tr><td>873.21 4*</td><td>3.44</td><td></td><td></td></tr><tr><td rowspan="4">154m<sup>1</sup>Tb</td><td rowspan="4">e.c., β+ 78.2%<br>IT 21.8%</td><td rowspan="4">9.4 h **</td><td>346.70 4*</td><td>1.63</td><td><sup>151</sup>Eu(α,n)</td><td>10.3</td></tr><tr><td>540.18 6</td><td>20.3</td><td><sup>153</sup>Eu(α,3n)</td><td>25.5</td></tr><tr><td>722.5 1*</td><td>0.37</td><td><sup>154m<sup>2</sup>Tb (IT)</sup></td><td></td></tr><tr><td>873.21 4*</td><td>11</td><td></td><td></td></tr><tr><td rowspan="3">154gTb</td><td rowspan="3"></td><td rowspan="3">21.5 h</td><td></td><td>9.2 16</td><td></td><td></td></tr><tr><td>722.12 8*</td><td>7.76</td><td><sup>151</sup>Eu(α,n)</td><td>10.3</td></tr><tr><td>873.21 4*</td><td>5.35</td><td><sup>153</sup>Eu(α,3n)</td><td>25.5</td></tr><tr><td></td><td></td><td></td><td></td><td></td><td><sup>154m<sup>1</sup>Tb (IT)</sup></td><td></td></tr></tbody></table>

* Overlapping peaks from the three isomers, other peaks were not considered due to important superpositions with other radionuclides

** Re-evalued by to be 9.994 39 h by Gyürky et al. (2009). Here the NuDat3.0 value was used for consistency

<figure><img src="image_46.png" /></figure>

<figure><img src="image_47.png" /><figcaption>natEu(α,x)¹⁵⁴m²Tb</figcaption></figure>

<figure><img src="image_48.png" /></figure>

m1 isomer is not reported in the output of TALYS 2.0 default
<figure><img src="image_49.png" /></figure>

<figure><img src="image_50.png" /></figure>

# natEu(α,x) – ¹⁵⁴gTb

## Key Issues:

**Spectral Overlaps:** Complex gamma-ray spectra hinder peak deconvolution.

**Nuclear Data Uncertainties:** Gamma intensity uncertainties: up to 20%.

**Isomeric Transition (IT) Discrepancies:**

Lau et al. (1973) report m1 → g IT probability of 21.8%; Bak et al. (1973) report 15%.

Lau et al. (1973) report m2 → m1 at 1.8%, but Live Chart indicates direct m2 → g transition.

NUBASE2020 state that experimental data insufficient to confirm ground state identity and that there is possibly no IT from m1,m2 → g.

## Experimental Observations:

* Dellepiane et al. (2022) report that ¹⁵⁴gTb activity shows **simple exponential decay**, inconsistent with significant m1 → g feeding.

* In present work, the **exclusion of ¹⁵⁴m¹Tb IT** contribution results in mutually consistent A⁵⁰B(¹⁵⁴gTb) across measurements. However limited post-EOB data points constrain decay curve reconstruction.

<figure><img src="image_51.png" /></figure>

<figure><img src="image_52.png" /></figure>

Dellepiane et al., Appl. Radiat. Isot., 184 (2022) 110175.
<figure><img src="image_53.png" /></figure>

natEu($\alpha$,x) – $^{154g}$Tb

<figure><img src="image_54.png" /></figure>

* $^{154}$Tb is not studied in Moiseeva et al. (2021)

* the cross-section of production of $^{154g}$Tb is not reported in Kormazeva et al. (2025)

<figure><img src="image_55.png" /></figure>

<figure><img src="image_56.png" /></figure>

WORK IN PROGRESS

<figure><img src="image_57.png" /></figure>

Future work must refine:

* IT intensities, gamma-emission probabilities,

* isomeric relationships, and

* decay scheme consistency
to enable reliable cross-section evaluations.
<figure><img src="image_58.png" /></figure>

<figure><img src="image_59.png" /></figure>

natEu(α,x) – others

<figure><img src="image_60.png" /></figure>

<figure><img src="image_61.png" /></figure>
<figure><img src="image_62.png" /></figure>

<figure><img src="image_63.png" /></figure>

natEu(α,x) – others

<figure><img src="image_64.png" /></figure>

<figure><img src="image_65.png" /></figure>
<figure><img src="image_66.png" /></figure>

<figure><img src="image_67.png" /></figure>

natEu(α,x) – others

<figure><img src="image_68.png" /></figure>

<figure><img src="image_69.png" /></figure>

<figure><img src="image_70.png" /></figure>

<figure><img src="image_71.png" /></figure>

<figure><img src="image_72.png" /></figure>
<figure><img src="image_73.png" /></figure>

<figure><img src="image_74.png" /></figure>

Considerations on production of ¹⁵⁵Tb
natEu(α,x) - 15xTb

<figure><img src="image_75.png" /></figure>

<figure><img src="image_76.png" /></figure>

<figure><img src="image_77.png" /></figure>

<figure><img src="image_78.png" /></figure>

<figure><img src="image_79.png" /></figure>

<figure><img src="image_80.png" /></figure>

<figure><img src="image_81.png" /></figure>

<table><thead><tr><th>RN</th><th>T<sub>1/2</sub></th><th>E<sub>th</sub> (<sup>151</sup>Eu) [MeV]</th><th>E<sub>th</sub> (<sup>153</sup>Eu) [MeV]</th></tr></thead><tbody><tr><td><sup>152</sup>Tb</td><td>17.5 h</td><td>26.2</td><td>41.1</td></tr><tr><td><sup>153</sup>Tb</td><td>2.34 d</td><td>17.4</td><td>32.5</td></tr><tr><td><sup>154</sup>Tb</td><td>21.5 h</td><td>10.3</td><td>25.5</td></tr><tr><td><sup>154</sup>mTb</td><td>9.4 h</td><td>10.3</td><td>25.5</td></tr><tr><td><sup>154</sup>mTb</td><td>22.7 h</td><td>10.3</td><td>25.5</td></tr><tr><td><sup>155</sup>Tb</td><td>5.32 d</td><td>1.0*</td><td>16.1</td></tr><tr><td><sup>156</sup>Tb</td><td>5.35 d</td><td>N/A</td><td>9.1</td></tr></tbody></table>

natEu(α,x)<sup>155</sup>Tb

<figure><img src="image_82.png" /></figure>
<figure><img src="image_83.png" /></figure>

natEu(α,x) - 15xTb

Production of ¹⁵⁵Tb on enriched ¹⁵³Eu?

<figure><img src="image_84.png" /></figure>

<table><thead><tr><th>RN</th><th>T<sub>1/2</sub></th><th>E<sub>th</sub> (¹⁵¹Eu) [MeV]</th><th>E<sub>th</sub> (¹⁵³Eu) [MeV]</th></tr></thead><tbody><tr><td>¹⁵²Tb</td><td>17.5 h</td><td>26.2</td><td>41.1</td></tr><tr><td>¹⁵³Tb</td><td>2.34 d</td><td>17.4</td><td>32.5</td></tr><tr><td>¹⁵⁴gTb</td><td>21.5 h</td><td>10.3</td><td>25.5</td></tr><tr><td>¹⁵⁴m¹Tb</td><td>9.4 h</td><td>10.3</td><td>25.5</td></tr><tr><td>¹⁵⁴m²Tb</td><td>22.7 h</td><td>10.3</td><td>25.5</td></tr><tr><td>¹⁵⁵Tb</td><td>5.32 d</td><td>1.0*</td><td>16.1</td></tr><tr><td>¹⁵⁶gTb</td><td>5.35 d</td><td>N/A</td><td>9.1</td></tr></tbody></table>

<figure><img src="image_85.png" /></figure>

<figure><img src="image_86.png" /></figure>

<figure><img src="image_87.png" /></figure>

<figure><img src="image_88.png" /></figure>
<figure><img src="image_89.png" /></figure>

# natEu(α,x) - 15xTb

## Production of ¹⁵⁵Tb on enriched ¹⁵³Eu?

**Key hypothesis:**

* Negligible contribute of the reaction ¹⁵¹Eu(α,γ)¹⁵⁵Tb (See *Gyurkyi et al. (2010))

* Negligible contribute of ¹⁵¹Eu(α,n)¹⁵⁴m₁,m²,gTb (based on experimental data trend)

<figure><img src="image_90.png" /></figure>

<table><thead><tr><th>RN</th><th>T<sub>1/2</sub></th><th>E<sub>th</sub> (¹⁵¹Eu) [MeV]</th><th>E<sub>th</sub> (¹⁵³Eu) [MeV]</th></tr></thead><tbody><tr><td>¹⁵²Tb</td><td>17.5 h</td><td>26.2</td><td>41.1</td></tr><tr><td>¹⁵³Tb</td><td>2.34 d</td><td>17.4</td><td>32.5</td></tr><tr><td>¹⁵⁴gTb</td><td>21.5 h</td><td>10.3</td><td>25.5</td></tr><tr><td>¹⁵⁴m¹Tb</td><td>9.4 h</td><td>10.3</td><td>25.5</td></tr><tr><td>¹⁵⁴m²Tb</td><td>22.7 h</td><td>10.3</td><td>25.5</td></tr><tr><td>¹⁵⁵Tb</td><td>5.32 d</td><td>1.0*</td><td>16.1</td></tr><tr><td>¹⁵⁶gTb</td><td>5.35 d</td><td>N/A</td><td>9.1</td></tr></tbody></table>

<figure><img src="image_91.png" /></figure>

<figure><img src="image_92.png" /></figure>

<figure><img src="image_93.png" /></figure>

<figure><img src="image_94.png" /></figure>
<figure><img src="image_95.png" /></figure>

# $^{153}\text{Eu}(\alpha,2n)^{155}\text{Tb}$

## Production of $^{155}\text{Tb}$ on enriched $^{153}\text{Eu}$?

**Key hypothesis:**

* Negligible contribute of the reaction $^{151}\text{Eu}(\alpha,\gamma)^{155}\text{Tb}$ (See *Gyurkyi et al. (2010))

* Negligible contribute of $^{151}\text{Eu}(\alpha,n)^{154}\text{m1,m2,gTb}$ (based on experimental data trend)

**Optimized irradiation conditions**

* $E_{\text{in}} = 28.5$ MeV, $\Delta E = 5$ MeV, $t_{\text{irr}} = 10$ h, waiting time: 2h

<figure><img src="image_96.png" /></figure>

<figure><img src="image_97.png" /></figure>

<table><thead><tr><th>Process</th><th>Source</th><th>Energy (MeV)</th><th>Target form</th><th>Target thickness (µm)</th><th>α<sub>phys</sub> [MBq/µA/h]</th><th>t<sub>dec</sub></th><th>RNP</th></tr></thead><tbody><tr><td><sup>155</sup>Gd(p,n)</td><td>G. Dellepiane et al. (2022)</td><td>10.5</td><td>(<sup>155</sup>Gd)Gd<sub>2</sub>O<sub>3</sub></td><td>300</td><td>3.4(±0.2)</td><td>4 d</td><td>93%</td></tr><tr><td><sup>156</sup>Gd(p,2n)</td><td>G. Dellepiane et al. (2022)</td><td>18.5</td><td>(<sup>156</sup>Gd)Gd<sub>2</sub>O<sub>3</sub></td><td>300</td><td>14.3(±0.7)</td><td>4 d</td><td>89%</td></tr><tr><td><sup>155</sup>Gd(d,2n)</td><td>Y. Wang et al. (2023)</td><td>15.1</td><td>(<sup>155</sup>Gd)Gd<sub>2</sub>O<sub>3</sub></td><td>390</td><td>10.2(±0.7)</td><td>14 d</td><td>89%</td></tr><tr><td><sup>153</sup>Eu(α,2n)</td><td>Kormazeva et al. (2025)</td><td>30.2</td><td>-</td><td>(2.7 MeV loss)</td><td>2.17</td><td>35 h</td><td>~ 90%</td></tr><tr><td><sup>153</sup>Eu(α,2n)</td><td>this work</td><td>28.5</td><td>(<sup>153</sup>Eu)Eu<sub>2</sub>O<sub>3</sub></td><td>54</td><td>2.2</td><td>2 d</td><td>97%</td></tr><tr><td><sup>159</sup>Tb(p,5n)<sup>155</sup>Dy<br/>-> <sup>155</sup>Tb</td><td>Colucci et al. (2024)</td><td>59</td><td>Tb<sub>2</sub>O<sub>3</sub></td><td>3000</td><td>1200 MBq·µA<sup>-1</sup>*</td><td>\ > 99,9 %</td><td></td></tr></tbody></table>

<footnote>* Only TTY is reported being an indirect process. RNP is the theoretical one.</footnote>
<figure><img src="image_98.png" /></figure>

<figure><img src="image_99.png" /></figure>

# Conclusions

1. Comprehensive of natEu(α,x) cross sections for medically relevant terbium isotopes (20–65 MeV).

2. Nuclear code needs to be optimized with respect to default options.

3. Optimized <sup>155</sup>Tb production via <sup>153</sup>Eu(α,2n): 97% purity achieved using a 28.5 MeV alpha beam energy with 5 MeV loss.

## Future directions:

* Scale up with enriched <sup>153</sup>Eu

* Thermal studies of Eu<sub>2</sub>O<sub>3</sub> targets

* Investigate <sup>154</sup>Tb decay schemes

<figure><img src="image_100.png" /></figure>

UNIVERSITÀ
DEGLI STUDI
DI MILANO

<figure><img src="image_101.png" /></figure>

INFN
LASA
Istituto Nazionale di Fisica Nucleare
Laboratorio Acceleratori e Superconductività Applicata

<figure><img src="image_102.png" /></figure>

<figure><img src="image_103.png" /></figure>
Thank you for your attention!

<figure><img src="image_104.png" /></figure>

michele.colucci@unimi.it

## Funding

This work has been funded by the CSN5 of the Italian National Institute of Nuclear Physics (INFN) through the project REMIX and by the CSN3 of INFN through the project SPES MED. The mobility has been partially supported by the ENEN2plus project (HORIZON-EURATOM-2021-NRT-01-13 101061677) funded by the European Union. The cyclotron Arronax is supported by CNRS, Inserm, INCa, the Nantes University, the Regional Council of Pays de la Loire, local authorities, the French government and the European Union. This work has been supported in part by the French National Research Agency (ANR) "France 2030 investment plan" under the references I-SITE NExT (ANR-16-IDEX-0007), and Labex DHOLMEN, by financial support from the Pays de la Loire Region and by a grant from INCa-DGOS-INSERM-ITMO Cancer 18011 (SIRIC ILIAD).
<figure><img src="image_105.png" /></figure>

# 12th International Conference on Isotopes

Florence, 15 – 19 February 2026

<figure><img src="image_106.png" /></figure>

UNIVERSITÀ
DEGLI STUDI
DI MILANO

INFN

Istituto Nazionale di Fisica Nucleare

WORLD COUNCIL ON ISOTOPES

WCI

<figure><img src="image_107.png" /></figure>

<figure><img src="image_108.png" /></figure>

<figure><img src="image_109.png" /></figure>

<figure><img src="image_110.png" /></figure>

<figure><img src="image_111.png" /></figure>

CONVENTION
BUREAU
ITALIA

<figure><img src="image_112.png" /></figure>

FirenzeFiera
Comune di Firenze

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REGIONE
TOSCANA

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TOSCANA
PROMOZIONE TURISTICA

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COMUNE DI
FIRENZE

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Camera di Commercio
Firenze

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## SCIENTIFIC PROGRAMME

* Isotope Production and Devices

* Applications of Isotopes

* Isotopes in the Environment

* Policy, Economics, and Global Impact of Isotope Production and Use

* Energy and decommissioning

* Security, Safety, and Quality Assurance

* Education and Training

* Marie Curie Session

* Young Scientists Forum

## LOCATION

Palazzo dei Congressi

Abstract submission is open!

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FLORENCE 15-19 FEB 2026

12th INTERNATIONAL
CONFERENCE ON ISOTOPES

CHAIR:

Prof. Flavia Groppi

CO-CHAIR:

Dr. Gaia Pupillo

Conference
Scientific Secretary:

Dr. Michele Colucci

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12ici@mi.infn.it

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12ICI – 12th International
Conference on Isotopes

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Backup slides
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Nuclear data of non isotopic contaminants

<table><tbody><tr><td><sup>153</sup>Gd<br>e.c. 100%</td><td>240.4 d</td><td>97.43100 21<br>103.18012 17</td><td>30.0 6<br>22.1 3</td><td><sup>151</sup>Eu(α,d)<br><sup>153</sup>Eu(α,n+t)<br><sup>153</sup>Tb (β<sup>+</sup>, 100%)<br><sup>153m</sup>Gd (IT, 100%)<br><sup>153m2</sup>Gd (IT, 100%)</td><td>12.72<br>21.47</td></tr><tr><td><sup>151</sup>Gd<br>e.c. 100%</td><td>123.9 d</td><td>153.60 1<br>174.70 1<br>243.29 3<br>307.50 1</td><td>6.2 4<br>2.96 20<br>5.6 4<br>1.04 7</td><td><sup>151</sup>Eu(α,n+t)<br><sup>153</sup>Eu(α,3n+t)<br><sup>151m</sup>Tb (β<sup>+</sup>, 6.6%)<br><sup>151</sup>Tb (β<sup>+</sup>, 99.99%)</td><td>21.46<br>36.59</td></tr><tr><td><sup>149</sup>Gd<br>e.c., β<sup>+</sup> 100%</td><td>9.28 d</td><td>149.730 10<br>298.633 5<br>346.650* 10</td><td>48.4 26<br>27.9 15<br>23.7 13</td><td><sup>151</sup>Eu(α,3n+t)<br><sup>153</sup>Eu(α,5n+t)<br><sup>149</sup>Tb (β<sup>+</sup>, 83.3%)<br><sup>149m</sup>Tb (β<sup>+</sup>, 99.98%)</td><td>36.95<br>52.07</td></tr><tr><td><sup>149</sup>Eu<br>e.c. 100%</td><td>93.1 d</td><td>277.089 10<br>327.526 10</td><td>4.18 4<br>4.75 5</td><td><sup>151</sup>Eu(α,α+2n)<br><sup>153</sup>Eu(α,α+4n)<br><sup>149</sup>Gd (β<sup>+</sup>, 100%)</td><td>14.63<br>29.75</td></tr><tr><td><sup>148</sup>Eu<br>e.c., β<sup>+</sup> 100%</td><td>54.5 d</td><td>550.284<sup>a</sup> 12<br>553.231<sup>a</sup> 14<br>553.260<sup>a</sup> 15<br>629.987 8</td><td>99 3<br>12.9 22<br>5.0 22<br>71.9 22</td><td><sup>151</sup>Eu(α,α+3n)<br><sup>153</sup>Eu(α,α+5n)<br><sup>148m</sup>Eu (IT, 100%)</td><td>38.12<br>23.00</td></tr></tbody></table>
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Monitor reactions

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# FUNDAMENTAL QUANTITIES - Physics

Thick-Target Yield (TTY)
[Bq · µA⁻¹]

$$Y(E, \Delta E, t) = \int_{E-\Delta E}^{E} y(E) dE \cdot \frac{(1 - e^{-\lambda t})}{\lambda}$$

Y(E, ΔE, t)

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Thin-target yield (tty)
[Bq · MeV⁻¹ · C⁻¹]

$$y(E) \stackrel{\text{def}}{=} \left[ \frac{\partial^2 \left( \frac{A}{i} \right)}{\partial E \partial t_{irr}} \right]_{t_{irr} \to 0} = \frac{\sigma(E) \cdot N_A \cdot \lambda}{M \cdot z_e \cdot \frac{dE}{\rho dx}(E)}$$

dE ≪ E

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ρdx

Cross-section
[b]

$$\sigma(E) = \frac{A \cdot M \cdot z_e}{\rho dx \cdot N_A \cdot Q \cdot \lambda \cdot m_{Eu\%}} \cdot G(t_{irr}) \cdot D(t_{count}) \cdot e^{\lambda \cdot t_{cool}}$$
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DECAY PROPERTIES

<table><thead><tr><th rowspan="2">Isotope</th><th rowspan="2">T<sub>1/2</sub></th><th colspan="2">Diagnostic</th><th colspan="3">Therapeutic</th></tr><tr><th>E<sub>aver</sub> (β<sup>+</sup>)<br>[keV] (I %)</th><th>X and γ with I > 10%<br>[keV] (I %)</th><th>E<sub>aver</sub> (β<sup>-</sup>)<br>[keV] (I %)</th><th>Conv.<br>& Auger (>1 keV)<br>E<sub>aver</sub> [keV] (I %)</th><th>E(α)<br>[keV] (I %)</th></tr></thead><tbody><tr><td><strong><sup>149</sup>Tb</strong></td><td>4.1 h</td><td><strong>730 (7%)</strong></td><td>42-50 (69%), 165 (26%),<br>352 (29%), etc.</td><td>-</td><td>32 (85%)</td><td><strong>3967 (17%)</strong></td></tr><tr><td><strong><sup>152</sup>Tb</strong></td><td>17.5 h</td><td><strong>1140 (20%)</strong></td><td>42-50 (65%), 344 (64%)</td><td>-</td><td>36 (69%)</td><td>-</td></tr><tr><td><strong><sup>155</sup>Tb</strong></td><td>5.32 d</td><td>-</td><td>42-50 (108%), <strong>87 (32%)</strong>,<br><strong>105 (25%)</strong></td><td>-</td><td><strong>19 (204%)</strong></td><td>-</td></tr><tr><td><strong><sup>161</sup>Tb</strong></td><td>6.89 d</td><td>-</td><td>45-53 (39%), <strong>75 (10%)</strong></td><td><strong>154 (100%)</strong></td><td><strong>19 (227%)</strong></td><td>-</td></tr></tbody></table>
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