arXiv subjects

Pedro V. Guillaumon

Publications and source records attributed to Pedro V. Guillaumon.

4 recordsLinked to original sources

arXiv2026

Reinvestigation of the Yield of the Trinity Device

Previous published analyses of trinitite to determine the yield of the Trinity nuclear explosion used various estimates of the fraction of fission products that became incorporated in trinitite. Furthermore, these studies utilized nuclear data that has subsequently been revised. Utilizing a planar germanium detector, we observed gamma rays produced by the decays of both 137Cs and 239Pu from four samples of trinitite. From the observed 137Cs/239Pu ratios of and a simple analysis method based on current nuclear data and weapons debris studies, we find an average yield of 9.1+-4.5 kilotons from our four samples. While this result is substantially lower than the established total yield of 21 kilotons, it is in reasonable agreement that attributable to fissions in the 239Pu core alone.

nucl-ex↗

arXiv2025

Measurement of Trace Elements in Volcanic Materials: Consequences for the Cretaceous-Tertiary Mass Extinction, Geoneutrinos and the Origin of the Hawaii's Archipelago

Seventeen representative samples of volcanic origin were collected from Ecuador (Pichincha Volcano), Iceland (Eyjafjallajökull Volcano), India (Deccan Traps), Hawaii, Kilimanjaro, Mt. Etna, Rwanda (Virunga Mountains), and Uganda (Virunga Mountains). Neutron activation analysis (NAA) was performed to determine the concentration of 33 chemical elements, including 21 trace elements, 20 heavy metals, and 9 rare earth elements: Al, As, Ba, Ca, Ce, Cl, Co, Cr, Cs, Dy, Eu, Fe, Hf, K, La, Lu, Mg, Mn, Na, Nd, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Th, Ti, U, Yb, Zn, and Zr. Correlation analysis of the abundance of samples from different islands in the Hawaii archipelago (Kauai, Kilauea, Mauna Loa, and Haleakala) confirmed that the islands were likely formed by two different lava sources. Additionally, the upper limit of iridium was determined in 11 of these samples using Bayesian analysis, which does not support the hypothesis that volcanic activity caused the extinction of the dinosaurs. We also discuss how the abundance of thorium and uranium in lava from different geological formations and depths can contribute to building a better map of natural radioisotope occurrences on Earth, which is important for geoneutrino experiments. A high abundance of rare elements was reported in some of the analyzed locations, indicating potential commercial interest and the possibility of exploring volcanoes as sources of chemical elements used in electronic devices.

physics.geo-ph↗

arXiv2023

LUCE: A milli-Kelvin calorimeter experiment to study the electron capture of 176Lu

The LUCE (LUtetium sCintillation Experiment) project will search for the 176Lu electron capture based on a milli-Kelvin calorimetric approach. This decay is of special interest in the field of nuclear structure, with implications for the s-process and for a better comprehension of the nuclear matrix elements of neutrinoless double beta decay (0ν\b{eta}\b{eta}) and two-neutrino double beta decay (2ν\b{eta}\b{eta}). Possible impacts also include the development of a new class of coherent elastic neutrino-nucleus scattering (CEνNS) and spin-dependent (independent) dark matter detectors. We report on the current status and design of a novel detector cryogenic-module for the measurement of the electron capture and detail a future measurement plan.

physics.ins-det↗

arXiv2020

The importance of charged particle reactions in the r-process on supernovae and neutron stars

We propose a $(p,xn)$ mechanism with dynamic production as a new set of nuclear reactions that could produce high density neutrons and explain the r- and rp-elements. We calculate the rate of thorium and uranium produced by our proposed mechanism and show that it is compatible with different stellar conditions found in explosive events at an initial temperature of $T \geq 3\times 10^{9} K$ with a "freeze-out" by a neutrino-driven wind. We show that charged particle reactions could explain the discrepancies in the abundances of ${}^{232}Th$ and ${}^{235,238}U$ nucleochronometers. We extend the endpoint of the rapid proton (rp) process far beyond the previous work by showing that $(p,xn)$ reactions could contribute to the nucleosynthesis of heavy stable neutron deficient nuclides, like ${}^{190}Pt$, ${}^{184}Os$, ${}^{180}W$ and ${}^{174}$Hf. This implies in a broader definition of the rp-process and has important consequences for the nucleosynthesis of heavy elements. We show that we did not need to assume an extreme condition for the drip line of super neutron-rich nuclei.

nucl-th↗