The dineutron correlation is systematically studied in three different Borromean nuclei near the neutron dripline, 11Li, 14Be and 17B, via the (p,pn) knockout reaction measured at the RIBF facility ...in RIKEN. For the three nuclei, the correlation angle between the valence neutrons is found to be largest in the same range of intrinsic momenta, which can be associated to the nuclear surface. This result reinforces the prediction that the formation of the dineutron is universal in environments with low neutron density, such as the surface of neutron-rich Borromean nuclei.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The Arabidopsis gene ZIM encodes a putative transcription factor containing a novel GATA-type zinc-finger domain with a longer spacer between its two sets of conserved cysteine residues ...(C-X2-C-X20-C-X2-C). In Arabidopsis, ZIM and homologous proteins, ZML1 and ZML2, were identified as GATA factors containing the C-X2-C-X20-C-X2-C motif, a CCT domain, and an uncharacterized conserved domain. Proteins that possess this domain structure were found exclusively in plants, indicating that they belong to a novel family of plant-specific GATA-type transcription factors. When ZIM was overexpressed using a CaMV 35S promoter in Arabidopsis, hypocotyls and petioles were elongated. The elongation phenotype was observed under all wavelengths of light tested and even in the presence of biosynthetic inhibitors of either brassinosteroid or gibberellin. In ZIM-overexpressing plants, XTH33 which is predicted to function in cell wall modification was detected as an up-regulated gene by microarray analysis, and this could account for the elongation phenotype. Genes in ZIM-overexpressing plants were identified that were up-regulated in a tissue-specific manner, which suggests that transcriptional regulation by ZIM and its consequent effects are spatially controlled.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
We present an investigation of the structure of 13Be obtained via a kinematically complete measurement of the (p,pn) reaction in inverse kinematics at 265 MeV/nucleon. The relative energy spectrum of ...13Be is compared to Transfer-to-the-Continuum calculations which use as structure inputs the overlaps of the 14Be ground-state wave function, computed in a three-body model, with the unbound states of the 13Be residual nucleus. The key role of neutron p-wave orbital in the interpretation of the low-relative-energy part of the spectrum is discussed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Spectroscopy of 16B plays an essential role in understanding the halo structure in 17B, but very limited knowledge has so far been obtained. We have carried out a kinematically complete measurement ...on the spectroscopy of 16B by using quasi-free (p,pn) reaction on 17B. The level scheme of 16B up to 5 MeV was made clear for the first time.
We have combined the low-energy neutron detector WINDS (Wide-angle Inverse-kinematics Neutron Detectors for SHARAQ) and the SAMURAI spectrometer at RIKEN Nishina Center RI Beam Factory (RIBF) in ...order to perform (p,n) reactions in inverse kinematics for unstable nuclei in the mass region around A∼100. In this setup, WINDS is used for detecting recoil neutrons and the SAMURAI spectrometer is used for tagging decay channel of heavy residue. The first experiment by using the setup was performed to study Gamow–Teller transitions from 132Sn in April 2014. The atomic number Z and mass-to-charge ratio A/Q of the beam residues were determined from the measurements of time of flight, magnetic rigidity and energy loss. The obtained A/Q and Z resolutions were σA/Q=0.14% and σZ=0.22, respectively. Furthermore, owing to the large momentum acceptance (50%) of SAMURAI, the beam residues associated with the γ, 1n and 2n decay channel were measured in the same magnetic field setting. The kinematic loci of the measured recoil neutron energy and laboratory angle are clearly seen. It shows that the excitation energy up to about 20MeV can be reconstructed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The isospin characters of low-energy dipole excitations in neutron-rich unstable nucleus 20O were investigated, for the first time in unstable nuclei. Two spectra obtained from a dominant isovector ...probe (O20+Au) and a dominant isoscalar probe (O20+α) were compared and analyzed by the distorted-wave Born approximation to extract independently the isovector and isoscalar dipole strengths. Two known 1− states with large isovector dipole strengths at energies of 5.36(5) MeV (11−) and 6.84(7) MeV (12−) were also excited by the isoscalar probe. These two states were found to have different isoscalar dipole strengths, 2.70(32)% (11−) and 0.67(12)% (12−), respectively, in exhaustion of the isoscalar dipole-energy-weighted sum rule. The difference in isoscalar strength indicated that they have different underlying structures.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP