Publications by authors named "T M Sprouse"

We demonstrate that the well-known 2.6 MeV gamma-ray emission line from thallium-208 could serve as a real-time indicator of astrophysical heavy element production, with both rapid (r) and intermediate (i) neutron capture processes capable of its synthesis. We consider the r process in a Galactic neutron star merger and show Tl-208 to be detectable from ∼12 hours to ∼ten days, and again ∼1-20  years postevent.

View Article and Find Full Text PDF

Nuclear isomer effects are pivotal in understanding nuclear astrophysics, particularly in the rapid neutron-capture process where the population of metastable isomers can alter the radioactive decay paths of nuclei produced during astrophysical events. The β-decaying isomer ^{128m}Sb was identified as potentially impactful since the β-decay pathway along the A=128 isobar funnels into this state bypassing the ground state. We report the first direct mass measurements of the ^{128}Sb isomer and ground state using the Canadian Penning Trap mass spectrometer at Argonne National Laboratory.

View Article and Find Full Text PDF

The Rare-RI Ring (R3) is a recently commissioned cyclotronlike storage ring mass spectrometer dedicated to mass measurements of exotic nuclei far from stability at Radioactive Isotope Beam Factory (RIBF) in RIKEN. The first application of mass measurement using the R3 mass spectrometer at RIBF is reported. Rare isotopes produced at RIBF-^{127}Sn, ^{126}In, ^{125}Cd, ^{124}Ag, ^{123}Pd-were injected in R3.

View Article and Find Full Text PDF

The composition of the early Solar System can be inferred from meteorites. Many elements heavier than iron were formed by the rapid neutron capture process (r-process), but the astrophysical sources where this occurred remain poorly understood. We demonstrate that the near-identical half-lives [Formula: see text] of the radioactive r-process nuclei iodine-129 and curium-247 preserve their ratio, irrespective of the time between production and incorporation into the Solar System.

View Article and Find Full Text PDF

Successful multidisciplinary evaluation of potentially resectable rectal adenocarcinoma depends on high-resolution preoperative magnetic resonance imaging (MRI). Magnetic resonance imaging accurately identifies important risk factors of local recurrence and distant metastasis, thus facilitating enhanced preoperative prognostic stratification and treatment. When combined with appropriate neoadjuvant chemotherapy and total mesorectal excision, the treatment of rectal cancer has dramatically improved.

View Article and Find Full Text PDF