Publications (22)
Electron-lattice interaction and structural stability of the oxy-borate Co3O2BO3
M. Matos
A theoretical study is carried out in the homometallic mixed valent ludwigite Co3O2BO3 using a modified tight binding methodology. The study focuses on the electronic properties of…
Magnetic Field Dependent Behavior of the CDW ground state in Per2M(mnt)2 (M = Au, Pt)
J. S. Brooks, D. Graf, E. S. Choi +4
The Per2M(mnt)2 class of organic conductors exhibit a charge density wave (CDW) ground state below about 12 K, which may be suppressed in magnetic fields of order 20 to 30 T. Howev…
Mg(, )Na reaction study for spectroscopy of Na
S. M. Cha, K. Y. Chae, A. Kim +16
The Mg(, )Na reaction was measured at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory in order to better constrain spins and parit…
Suppression of a charge density wave ground state in high magnetic fields: spin and orbital mechanisms
D. Graf, J. S. Brooks, E. S. Choi +4
The charge density wave (CDW) transition temperature in the quasi-one dimensional (Q1D) organic material of (Per)Au(mnt) is relatively low (TCDW = 12 K). Hence in a mean fi…
Beta-decay half-lives and beta-delayed neutron emission probabilities of nuclei in the region below A=110, relevant for the r-process
J. Pereira, S. Hennrich, A. Aprahamian +21
Measurements of the beta-decay properties of r-process nuclei below A=110 have been completed at the National Superconducting Cyclotron Laboratory, at Michigan State University. Be…
Gamow-Teller strengths in 24Na using the 24Mg(t,3He) reaction at 115 AMeV
M. E. Howard, R. G. T. Zegers, Sam M. Austin +16
Gamow-Teller transitions from 24Mg to 24Na were studied via the (t,3He) reaction at 115 AMeV using a secondary triton beam produced via fast fragmentation of 150 AMeV 16O ions. Com…
-Decay Half-Life of the -Process Waiting Point Nuclide Mo
J. B. Stoker, P. F. Mantica, D. Bazin +15
A half-life of 2.2 0.2 s has been deduced for the ground-state decay of Mo, more than 1 shorter than the previously adopted value. Mo is an even-even N…
Precision spectroscopy of pionic 1s states of Sn nuclei and evidence for partial restoration of chiral symmetry in the nuclear medium
K. Suzuki, M. Fujita, H. Geissel +17
Deeply bound 1s states of in Sn were preferentially observed using the Sn(,He) pion-transfer reaction under the recoil-free condition. The 1s binding…
Beta-delayed proton emission in the 100Sn region
G. Lorusso, A. Becerril, A. Amthor +25
Beta-delayed proton emission from nuclides in the neighborhood of 100Sn was studied at the National Superconducting Cyclotron Laboratory. The nuclei were produced by fragmentation…
Neutron transfer reactions on the ground state and isomeric state of a 130Sn beam
K. L. Jones, A. Bey, S. Burcher +23
The structure of nuclei around the neutron-rich nucleus 132Sn is of particular interest due to the vicinity of the Z = 50 and N = 82 shell closures and the r-process nucleosyntheti…
High magnetic field induced charge density wave states in a quasi-one dimensional organic conductor
D. Graf, E. S. Choi, J. S. Brooks +3
We have measured the high field magnetoresistence and magnetization of quasi-one- dimensional (Q1D) organic conductor (Per)2Pt(mnt)2 (where Per = perylene and mnt = maleonitriledit…
Low-lying level structure of Cu and its implications on the rp process
W-J. Ong, C. Langer, F. Montes +39
The low-lying energy levels of proton-rich Cu have been extracted using in-beam -ray spectroscopy with the state-of-the-art -ray tracking array GRETINA in conjunctio…
Beta-decay of nuclei around Se-90. Search for signatures of a N=56 sub-shell closure relevant the r-process
M. Quinn, A. Aprahamian, J. Pereira +26
Nuclear structure plays a significant role on the rapid neutron capture process (r-process) since shapes evolve with the emergence of shells and sub-shells. There was some indicati…
Time-of-flight mass measurements for nuclear processes in neutron star crusts
A. Estrade, M. Matos, H. Schatz +23
The location of electron capture heat sources in the crust of accreting neutron stars depends on the masses of extremely neutron-rich nuclei. We present first results from a new im…
New isotope 44Si and systematics of the production cross sections of the most neutron-rich nuclei
O. B. Tarasov, T. Baumann, A. M. Amthor +13
The results of measurements of the production of neutron-rich nuclei by the fragmentation of a 48Ca beam at 142 MeV/u are presented. Evidence was found for the production of a new…
Low lying magnetic states of the mixed valence cobalt ludwigite
M. Matos, J. Terra, D. E. Ellis
There are two interpretations offered for the different structural and magnetic properties of the mixed valence homo-metallic ludwigites, Co3O2BO3 and Fe3O2BO3. One of them associa…
R-process Experimental Campaign at the National Superconducting Cyclotron Laboratory
J. Pereira, S. Hennrich, M. Quinn +19
A JINA/VISTARS r-process campaign was completed at the A1900 Fragment Separator of the National Superconducting Cyclotron Laboratory in the fall of 2005. The purpose of the campaig…
Magnetic Field Dependence of CDW Phases in Per2M(mnt)2 (M=Pt, Au)
J. S. Brooks, D. Graf, E. S. Choi +4
Recently the authors discovered that the suppression of the charge density wave (CDW) ground states by high magnetic fields in the organic conductor series Per2M(mnt)2 is followed…
Beta decay studies of r-process nuclei at the National Superconducting Cyclotron Laboratory
J. Pereira, A. Aprahamian, O. Arndt +22
The impact of nuclear physics on astrophysical r-process models is discussed, emphasizing the importance of beta-decay properties of neutron-rich nuclei. Several r-process motivate…
Reactions of a Be-10 beam on proton and deuteron targets
K. T. Schmitt, K. L. Jones, S. Ahn +30
The extraction of detailed nuclear structure information from transfer reactions requires reliable, well-normalized data as well as optical potentials and a theoretical framework d…
High-spin μs isomeric states in 96Ag
A. D. Becerril, G. Lorusso, A. M. Amthor +24
The isomeric and β decays of the N = Z +2 nucleus 96Ag were investigated at NSCL. A cascade of γ-ray transitions originating from the de-excitation of a μs isomer was observed f…
Recent direct reaction experimental studies with radioactive tin beams
K. L. Jones, S. Ahn, J. M. Allmond +40
Direct reaction techniques are powerful tools to study the single-particle nature of nuclei. Performing direct reactions on short-lived nuclei requires radioactive ion beams produc…