Publications by authors named "Surbrook J"

The upcoming UCNProBe experiment at Los Alamos National Laboratory will measure the beta decay rate of free neutrons with different systematic uncertainties than previous beam-based neutron lifetime experiments. We have tested a new 10B-coated Yttrium Aluminum Perovskite (YAP:Ce) scintillator and present its properties. The advantages of the YAP:Ce scintillator include its high Fermi potential, which reduces the probability for upscattering of ultracold neutrons (UCN), and its short decay time, which increases sensitivity at high counting rates.

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For the first time, the (d,^{2}He) reaction was successfully used in inverse kinematics to extract the Gamow-Teller transition strength in the β^{+} direction from an unstable nucleus. The new technique was made possible by the use of an active-target time-projection chamber and a magnetic spectrometer, and opens a path to addressing a range of scientific challenges, including in astrophysics and neutrino physics. In this Letter, the nucleus studied was ^{14}O, and the Gamow-Teller transition strength to ^{14}N was extracted up to an excitation energy of 22 MeV.

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A narrow near-threshold proton-emitting resonance (E_{x}=11.4  MeV, J^{π}=1/2^{+}, and Γ_{p}=4.4  keV) was directly observed in ^{11}B via proton resonance scattering.

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The ^{30}P(p,γ)^{31}S reaction plays an important role in understanding the nucleosynthesis of A≥30 nuclides in oxygen-neon novae. The Gaseous Detector with Germanium Tagging was used to measure ^{31}Cl β-delayed proton decay through the key J^{π}=3/2^{+}, 260-keV resonance. The intensity I_{βp}^{260}=8.

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The primary challenge in directly measuring nuclear reaction rates near stellar energies is their small cross sections. The signal-to-background ratio in these complex experiments can be significantly improved by employing high-current (mA-range) beams and novel detection techniques. Therefore, the electron cyclotron resonance ion source at the Laboratory for Experimental Nuclear Astrophysics underwent a complete upgrade of its acceleration column and microwave system to obtain high-intensity, pulsed proton beams.

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We report the mass measurement of ^{56}Cu, using the LEBIT 9.4 T Penning trap mass spectrometer at the National Superconducting Cyclotron Laboratory at Michigan State University. The mass of ^{56}Cu is critical for constraining the reaction rates of the ^{55}Ni(p,γ) ^{56}Cu(p,γ) ^{57}Zn(β^{+}) ^{57}Cu bypass around the ^{56}Ni waiting point.

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