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Low-mass neutron stars are directly associated with the nuclear saturation parameters because their central density is definitely low. We have already found a suitable combination of nuclear saturation parameters for expressing the neutron star mass and gravitational redshift, i.e., $\eta\equiv (K_0L^2)^{1/3}$ with the incompressibility for symmetric nuclear matter, $K_0$, and the density-dependent nuclear symmetry energy, $L$. In this study, we newly find another suitable combination given by $\eta_\tau\equiv (-K_\tau L^5)^{1/6}$ with the isospin dependence of incompressibility for asymmetric nuclear matter, $K_\tau$, and derive the empirical relations for the neutron star mass and gravitational redshift as a function of $\eta_\tau$ and the normalized central number density. With these empirical relations, one can evaluate the mass and gravitational redshift of the neutron star, whose central number density is less than threefold the saturation density, within $\sim 10\%$ accuracy, and the radius within a few \% accuracies. In addition, we discuss the neutron star mass and radius constraints from the terrestrial experiments, using the empirical relations, together with those from the astronomical observations. Furthermore, we find a tight correlation between $\eta_\tau$ and $\eta$. With this correlation, we derive the constraint on $K_\tau$ as $-348\le K_\tau\le -237$ MeV, assuming that $L=60\pm 20$ and $K_0=240\pm 20$ MeV., Comment: Accepted for publication in RPD. arXiv admin note: text overlap with arXiv:2203.09004

Nuclear magic numbers, which emerge from the strong nuclear force based on quantum chromodynamics, correspond to fully occupied energy shells of protons, or neutrons inside atomic nuclei. Doubly magic nuclei, with magic numbers for both protons and neutrons, are spherical and extremely rare across the nuclear landscape. While the sequence of magic numbers is well established for stable nuclei, evidence reveals modifications for nuclei with a large proton-to-neutron asymmetry. Here, we provide the first spectroscopic study of the doubly magic nucleus $^{78}$Ni, fourteen neutrons beyond the last stable nickel isotope. We provide direct evidence for its doubly magic nature, which is also predicted by ab initio calculations based on chiral effective field theory interactions and the quasi-particle random-phase approximation. However, our results also provide the first indication of the breakdown of the neutron magic number 50 and proton magic number 28 beyond this stronghold, caused by a competing deformed structure. State-of-the-art phenomenological shell-model calculations reproduce this shape coexistence, predicting further a rapid transition from spherical to deformed ground states with $^{78}$Ni as turning point.

International audience; The 9C breakup reaction was investigated in order to obtain information about the inverse reaction: 8B(p,γ)9C at astro-physical energies within the NP1412SAMURAI29R1 experiment. The 8B(p,γ)9C reaction gives a possible path to the hot pp chain pp-IV at high temperatures and away from it toward a rapid alpha-process rap-I at high temperatures and densities and therefore is important in understanding nucleosynthesis in super-massive hot stars in the early universe, including possible bypass of the 3α-process. For this experiment it was proposed to use a combination of nuclear and Coulomb dissociation measurements (on a light target Be or C and on a heavy target Pb, respectively) at energy of 160 A MeV to extract structure information, which will allow to evaluate the radiative proton capture cross section at low energies and from there the reaction rate. The current work is focused on the development of Monte Carlo simulations for Coulomb breakup mechanism of 9C as well as on the Geant4 simulations of the resulting particle trajectories through the experimental setup, including passage of the particles through the magnetic field of the SAMURAI spectrometer.

International audience; The dependence of the single-particle strength on the difference between proton and neutron separation energies is studied for oxygen isotopes in a wide range of isospins. The cross sections of the quasi-free (p, 2p) reaction on 14,16,18,22,24O were measured at intermediate energies. The measured cross sections are compared to predictions based on the distorted wave impulse approximation and shell-model psd valence-space spectroscopic factors. The reduction factors, which are the ratio of the experimental cross sections to the theoretical predictions, show no apparent dependence on the proton–neutron separation energy difference. The result is compatible with the result of the (e, e p) reaction on stable targets and with the predictions of recent ab initio calculations.

A new neutron detector has been designed to detect low-energy neutrons in (p,n) charge- exchange reactions in inverse kinematics. Our detector based on EJ-299-34 plastic scintillator and coupled to digital readout system which provides opportunity for pulse shape discrimination (PSD) of the detected particles as well as intelligent triggering based on PSD. This device enables one to reduce the gamma-ray background by one order of magnitude. We plan to use it in our experiments to study the spin-isospin responses of nuclei along the neutron drip line. The new system can be used, however, for any reaction study that involves emission of low-energy neu- trons (100 keV–1 MeV) where the background suppression and the increased signal-to-noise ratio are crucial.

We conducted an inclusive missing-mass spectroscopy of 122Sn (d, 3He) reaction near the π¯ emission threshold at an incident energy of T d = 250 MeV/nucleon. The experiment sets its goals to the research and development of the high precision spectroscopy of pionic atoms at the RI beam factory (RIBF) of RIKEN, which precedes a new project, pionic atom factory project (piAF), to observe pionic atoms systematically. Here, we report the preliminary results of the pilot experiment.

We have measured the energy spectrum of pionic 121Sn atoms by missing-mass spectroscopy of the 122Sn(d, 3He) reaction near the π − emission threshold. The measurement serves as a pilot experiment for high precision systematic spectroscopy of deeply bound pionic atoms in a new pionic Atom Factory project (piAF) at the RI beam factory (RIBF) of RIKEN. The status of the analysis is reported.

An experiment of 22 Mg and 20 Ne beams bombarding on a 12 C target at an energy of 60~70 A MeV has been performed at the RIKEN projectile fragment separator (RIPS) in the RIKEN Ring Cyclotron Facility to study the two-proton correlated emission from 22 Mg and 20 Ne excited states. The two-protons momentum correlation functions have been obtained for 22 Mg and 20 Ne , respectively. The trajectories of the 22 Mg decayed products (20 Ne + p + p ) were also measured to get the angular correlations between the two protons in Center of Mass of decaying system by relativistic-kinematics reconstruction. The results exhibit that 22 Mg has the features of 2 He cluster decay mechanism.

A rotational band with five cascade γ-ray transitions was newly found in 40 Ar . The deduced transition quadrupole moment of [Formula: see text] has demonstrated this band as having a superdeformed shape of β2 ~ 0.5. The structure of the band was discussed in the framework of cranked Hartree-Fock-Bogoliubov calculations and the assignment of multiparticle–multihole configuration has been made.

Proton inelastic scattering on the neutron-rich nucleus 32 Mg has been experimentally studied at E lab = 46.5 MeV / nucleon in inverse kinematics. The energies of excited states in 32 Mg were obtained by measuring de-excitation γ rays. Several new states were identified by γ-γ coincidence analysis. Their spins and parities were restricted and the deformation parameters βp,p′ were extracted from the measured angular distribution of the proton inelastic scattering. The present analysis favors 4+ for the spin and parity of the 2321-keV state.

The neturon rich nucleus 13B was studied via the proton transfer reaction 4He(12Be,13B \gamma) at 50AMeV. The known 4.83-MeV excited state was strongly populated and its spin and parity were assigned to 1/2+ by comparing the angular differential cross section data with DWBA calculations. This low-lying 1/2+ state is interpreted as a proton intruder state and indicates a deformation of the nucleus., Comment: 16 pages, 3 figures

The structure of the neutron rich pf-shell nuclei 58Ti36, 60Cr36 and 62Cr38 was studied by proton inelastic scattering in inverse kinematics. Large quadrupole deformation lengths of 1.12(16) fm and 1.36(14) fm were obtained for 60Cr and 62Cr, respectively, which confirm the enhanced collectivity in these nuclei. An excited state was observed in 62Cr at 1180(10) keV with tentative assignment of J π = 4 + . The increase in the E x ( 4 + ) / E x ( 2 + ) ratio indicates that the nature of collectivity changes from vibrational to rotational in 62Cr and affords evidence for the development of static deformation. The excitation energy of the newly observed 2+ state in 58Ti (1046(17) keV) shows hindered collectivity. The contrast between the structures of Cr and Ti suggests that the contributions of both protons and neutrons are crucial for the large collectivity in Cr close to N = 40 . From the comparison to shell model calculations, the large collectivity is found to originate from the admixture of the pf- and gd-shells across the N = 40 sub-shell gap.

This paper reports on the 1H(28Ne,28Ne) and 1H(28Ne,27Ne) reactions studied at intermediate energy using a liquid hydrogen target. From the cross section populating the first 2+ excited state of 28Ne, and using the previously determined B(E2) value, the neutron quadrupole transition matrix element has been calculated to be Mn=13.8 ±3.7 fm2. In the neutron knock-out reaction, two low-lying excited states were populated in 27Ne. Only one of them can be interpreted by the sd shell model while the additional state may intrude from the fp shell. These experimental observations are consistent with the presence of fp shell configurations at low excitation energy in 27,28Ne nuclei caused by a vanishing N=20 shell gap at Z=10.

Mean lifetime tau of the isomeric O-2(+) state in Be-12 has been determined by measuring decay spectra of delayed y-rays from stopped Be-12 2 nuclei produced by the projectile fragmentation of O-18 at 100 A MeV. A consistent value of tau = 331 +/- 12 ns was obtained from the time spectra of the E2 gamma decay to the 2(1)(+) state and the positron annihilation following the E0 decay to the ground state. Based on the observed branching ratio between the E2 and E0 decays, transition strengths of the two decay modes were deduced to be B(E2; O-2(+) -> 2(1)(+)) = 7.0 +/- 0.6 e(2) fm(4) and 2 1 1 (O-2(+) Sigma(i) e(i) r(i)(2) O-1(+)), = 0.87 +/- 0.03 e fM(2), respectively. (C) 2007 Elsevier B.V. All rights reserved.

Japan is located in the Asian monsoon climatic zone and these climatic conditions are favourable for growing rice in summer. In every age, rice fields have produced the staple food of the Japanese people and have also been the source of the multifunctional roles of agriculture. This paper describes the evolution of rice field drainage in Japan focusing on the last 60 years. The productivity-oriented drainage policy has been shifted to place emphasis on coping with discharge from expanding rural areas, corresponding to the social and economic background of the country. In recent years, irrigation and drainage facilities that take the environment into consideration have been actively introduced. This leads a new agricultural policy to conserve and improve the land, water and environment, the key factor of which is the creation of new local organizations including non-farmers. In view of technical aspects, various methods have been developed and applied in order to plan, design and install/improve main drainage facilities, field surface drainage, and field subsurface drainage. Various examples of restoring the ecosystem inherent to rice fields are introduced, including simple fish ladders and stairway-like fish passages. Technical standards are also introduced in terms of drainage system layout, structure of subsurface drainage and design drainage rate. Copyright © 2007 John Wiley & Sons, Ltd.

A rotational band from \(7/2^{ - }\) to \(19/2^{ - }\) was observed in ^35S. The half-life of the transition from the \(19/2^{ - }\) state to \(15/2^{ - }\) state was determined by using the residual Doppler shift of the \(\gamma \)-ray peak. The deduced half-life and the relative intensities of in-band transitions indicate the presence of superdeformed structure in ^35S. The shell model calculation showed that multi-particle multi-hole configurations including \(f_{7/2}\) orbitals are essential for superdeformation in ^35S.

Stucture of N = 17,18 nuclei has been investigated via proton inelastic scattering and neutron removal reactions up to the neutron dripline in inverse kinematics by use of radioctive ion beams provided by the RIKEN isotope separator, RIPS. Low energy excited states have been found in all the 26,27F and 27Ne nuclei, which are out of the neutron sd shell configuration space and are considered as intruder states arisng from cross shell excitations. Monte-Carlo shell model calculations with the sdpf-m interaction predict low energy negative parity excited states from neutron cross shell excitation at N = 17,18, which is in agreement with our experimental results. Observation of intruder states even at N = 17, especially the p3/2 state in 27Ne at 765 keV is a clear indication of a vanishing N = 20 shell gap at Z = 8 as predicted by the sdpf-m shell model calculations.

The proton shell structure in neutron-rich fluorine 23F was investigated using the in-beam γ-ray spectroscopy technique via the proton transfer reaction onto the 22O nucleus. We also measured the α inelastic scattering on 23F, the neutron knockout from 24F, and the two-nucleon knockout from 25Ne using a cocktail secondary beam. By comparison of the population strengths for excited states in these reactions, we deduced the character of the excited states. The levels and γ-decay scheme in 23F were proposed based on de-excitation γ-rays and the products of these reactions. We found that the 2268- and 4059-keV levels have strong proton single-particle nature of the s 1 / 2 and d 3 / 2 orbitals, respectively, by analysis of the population strengths and the angular distributions of the states. These single-particle states are located at higher excitation energies than the shell model predictions for the USD and SDPF-M interactions, which indicates that the centroid energy gaps for π d 5 / 2 – π s 1 / 2 and π d 5 / 2 – π d 3 / 2 are wider than predicted.

The paper reports on the test of the newly developed RIKEN-ATOMKI CsI(Tl) array. It is demonstrated that high-quality detectors with excellent light collection efficiency and narrow resolution distribution could be produced. The setup has been commissioned in the study of the reaction of 22O + CD2. In the present paper, we summarize the results mainly on the (d, d′) channel. From the cross section for the transition between the ground state and the first 2+ state, we could deduce the “matter” deformation parameter to be β M=0.23±0.02 by distorted wave analysis. Comparing this data with previous measurements it can be concluded that 22O isotope has moderate and similar neutron and proton deformations.

The Coulomb dissociation of 27P was studied experimentally using 27P beams at 57 MeV/nucleon with a lead target. The E2 gamma decay width of the first excited state in 27P was determined to be (2.8 ± 0.5) × 10−5 eV. The total (M1+E2)gamma decay width of the state, which is of astrophysical interest, is estimated by combining the experimental result and a shell model calculation. The reaction rate of 26Si(p, γ)27P is deduced from the estimated total gamma decay width. The astrophysical implication derived from estimated gamma decay width is discussed.

In orthognathic surgery cases, where patients have facial deformities and temporomandibular diseases, like osteoarthritis, exacerbation of the disease after surgery may occur. Therefore, the timing and procedures of the surgery need to be well managed, as well as the control of the occlusion after the operation. We report two cases with maxillary protrusion and mandibular retrognathism combined with severe osteoarthrosis of the temporomandibular joint (TMJ). The patients underwent surgical orthodontic treatment, where the maxilla was impacted and the mandible replaced forwardly. After the surgery, we placed a bone screw at the alveolar bone for the longterm use of intraoral elastics as a fixing to prevent skeletal relapse, and achieved a good functional occlusion and good esthetic results. We consider that the result of these treatments shows the effectiveness of the bone screw for preventing skeletal relapse after operation. Our first case was afemale patient of 18 years old, who reported that at the age of 9, she had received orthodontic treatment due to crowding of theteeth and ended the active treatment when she was 12 years old. She came to our office with an open bite and a posterior mandible placement, which became evident to her a year earlier. In the second case, a 20-year-old female patient reported that at the age of 10 she had clicking at both TMJs, frequently could not open her mouth and often had pain at the TMJ, but she had not sought treatment at that time. The patient came to us citing posterior mandibular placement as her chief complaint. The first case showed clicking at the maximum mouth opening and the second case showed clicking during both the opening and closing of the mouth, without finding the opening difficulties of the mouth that she had had before. Although X-ray and CT images revealed for both cases a severe condylar resorption, the cortical bone was present, with no evidence found by Tc scintigraphy of the TMJ. Both patients received orthodontic treatment prior to surgery, with impaction of the maxilla and forward replacement of the mandible. The bone screw remained for 12 months for the first case and for 7 months for the second case. Although both the facial appearance and the occlusion achieved are good and both have asymptomatic TMJs, the second case showed slight worsening of the condylar deformation after removal of the bone screw.

By taking advantage of the high efficiency of the Coulomb dissociation method, we studied the stellar 22Mg(p, γ)23Al reaction. The radiative width Γγ of the first excited state in 23Al was determined by measuring the intermediate-energy 23Al → 22Mg + p breakup process with a lead target.

The Coulomb dissociation of 27 P was studied experimentally using 27 P beams at 57 MeV/nucleon with a lead target. The E2 gamma decay width of the first excited state in 27 P was extracted. Assuming the same E2/M1 mixing ratio as the one for the mirror nucleus 27 Mg, the gamma decay width of the state, which is of astrophysical interest, is estimated to be ten times smaller than the value calculated by J. A. Caggiano et al.

The proton shell structure in neutron-rich fluorine 23F was investigated using the in-beam γ-ray spectroscopy technique via the proton transfer reaction onto the unstable nucleus 22O, in addition to α inelastic scattering on 23F, and the neutron-knockout reaction from 24F. The level and γ-decay scheme in 23F was deduced from de-excitation γ-ray-particle coincidence events. We found that a single-particle state at 4.061 MeV has a large contribution from the d shell by the analysis of population strengths and the angular distribution for the state. We reported here the present experiment and the preliminary results.

A measurement of the direct two-proton removal from Si42 has provided the first structural information on the N=28 isotone Mg40. The value for the inclusive cross section for two-proton removal from Si42 of 40+27−17 μb is significantly lower than that predicted by structure calculations using the recent SDPF-MU shell-model effective interaction combined with eikonal reaction theory. This observed discrepancy is consistent with the interpretation that only one of the predicted low-lying 0+ states in Mg40 is bound. A two-state mixing analysis describing two-proton knockout cross sections along N=28 provides support for the interpretation of a prolate-deformed Mg40 ground state.

Extensive allelotyping studies have implicated several tumor-suppressor loci on chromosomes 3p, 5q, 6q, 8p, 9pq, 10q, 11q, 14q, 17p, 18q and 19p in human kidney tumorigenesis. The PTEN (also called MMAC1 and TEP1) gene, a candidate tumor suppressor located at chromosome 10q23.3, is mutated in a variety of sporadic malignancies as well as in patients with Cowden disease. To investigate the potential role of the PTEN gene in renal tumorigenesis, we searched for abnormalities of the gene in 68 primary renal-cell carcinomas (RCCs) as well as in 17 renal carcinoma–derived cell lines, using DNA-SSCP, sequencing and microsatellite analysis. Five of 68 (7.5%) primary RCCs exhibited intragenic mutations (3 missense, 1 deletion and 1 splice-site), and 1 of 17 (5.9%) cell lines had an insertion mutation. Loss of heterozygosity of the PTEN gene occurred in 25% of primary RCCs, including the 3 cases with intragenic mutation and the 1 PTEN-mutated cell line. Clinical and histopathological examinations revealed that 4 of the 5 primary tumors with PTEN mutation were high-grade, advanced clear-cell RCCs with distant metastases or renal vein tumor invasions, resulting in poor prognostic courses. The other was a low-stage papillary/chromophilic RCC. Our data suggest that PTEN mutation is observed in a subset of RCCs and that, especially in clear-cell RCCs, it occurs as a late-stage event and may contribute to the invasive and/or metastatic tumor phenotype. © 2001 Wiley-Liss, Inc.

25th International Nuclear Physics Conference, Florence, Italy, 2 Jun 2013 - 7 Jun 2013; The European physical journal / Web of Conferences Web of Conferences : proceedings proceedings 66, 09014 (2014). doi:10.1051/epjconf/20146609014, Published by EDP Sciences, Les Ulis

Structure of the neutron-rich Ge isotopes at and around N = 50 has been investigated via intermediate-energy Coulomb excitation using secondary beams of 78-82Ge incident on a Pb target. The B(E2) values for the low-lying 2+ states have been extracted and compared with the data for neighboring isotopes around N = 50. In addition, a new method of intermediate-energy two-step Coulomb excitation has been proposed as a spectroscopic tool to study the 4+ states in neutron-rich even-even nuclei. The first application of the method and its results are presented.

Inclusive multineutron and multiproton removal cross sections from 112Sn and 104Sn at relativistic energies have been measured. The data show two distinct regimes of the reaction process that depend on the nucleon evaporation cost of the final nucleus. This behavior is universal by regarding the mass or asymmetry of the initial system or target composition. A state-of-the-art cascade and deexcitation model reproduces the observed trend but systematically fails in reproducing cross sections for the removal of the more bound nucleon species. © 2013 American Physical Society., A. Jungclaus acknowledges support from the Spanish Ministerio de Ciencia e Innovacion under Contracts No. FPA2009-13377-C02-02 and No. FPA2011-29854-C04-01.

The structure of the neutron-rich nucleus ${}^{58}$Ti was investigated via proton inelastic scattering in inverse kinematics at a mean energy of 42.0 MeV/nucleon. By measuring the deexcitation $\ensuremath{\gamma}$ rays, three transitions with the energies of 1046(11) keV, 1376(18) keV, and 1835(27) keV were identified. The angle-integrated cross section for the 1046-keV excitation, which corresponds to the decay from the first 2${}^{+}$ state, was determined to be 13(7) mb. The deformation length ${\ensuremath{\delta}}_{p,{p}^{\ensuremath{'}}}$ was extracted from the cross section to be ${0.83}_{\ensuremath{-}0.30}^{+0.22}$ fm. The energy of the first 2${}^{+}$ state and the ${\ensuremath{\delta}}_{p,{p}^{\ensuremath{'}}}$ value are comparable to the ones of ${}^{56}$Ti, which indicates that the collectivity of the Ti isotopes does not increase significantly with neutron number until $N=36$. This fact indicates that ${}^{58}$Ti is outside of the region of the deformation known in the neutron-rich nuclei around $N=40$.