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Ultracold muonium (UCMu) is an important muonium (Mu) source for the generation of ultraslow muon beam for nanotechnological applications and understanding hydrogen dynamics in materials. In order to search for a new solid material for the generation of UCMu in vacuum, we have studied polycrystalline SiC using conventional muon spin rotation and relaxation method at low temperatures (5 K – 300 K). The high relaxation rates of Mu formed deep inside from the surface (full-stop case) and near the rear surface (half-stop case) were observed at low transverse field (TF 1.2 G). The relaxation rates of Mu at different temperatures in full-stop and half-stop cases were found to be the same within error-bars indicating the less possibility of emission of the UCMu from the surface of the SiC. We plan further study in KCl, porous silica, and chevron shaped electron rich microporuos materials.

At J-PARC MUSE, since the µSR2017 conference and up to FY2022, there have been several new developments at the facility, including the completion of a new experimental area S2 at the surface muon beamline S-line and the first muon beam extraction to the H1 area in the H-line, mainly to carry out high-statistics fundamental physics experiments. Several new studies are also underway, such as applying negative muon non-destructive elemental analysis to the analysis of samples returned from the asteroid Ryugu in the D2 area of the D-line. This paper reports on the latest status of MUSE.

We present the first application of double-stage diamond anvil cells (ds-DACs) to X-ray absorption spectroscopy (XAS) of Rhenium (Re) metal. By using highly stable and sub-micron sized X-ray beam, ...

In this study, atomic-scale origin of the Invar effect, which is nearly-zero thermal expansion observed in the Invar alloy ${\mathrm{Fe}}_{65}{\mathrm{Ni}}_{35}$, was investigated by reverse Monte Carlo analysis using complementary data sets of extended x-ray absorption fine structure and x-ray diffraction. The interatomic distances of the nearest neighboring Fe-Fe atomic pairs were $\ensuremath{\sim}0.02$ \AA{} longer than those of the Fe-Ni and Ni-Ni pairs at the minimum pressure in this study (0.6 GPa). The elongation in the Fe-Fe pairs was suppressed with increasing pressure, and the distances of the three pairs were comparable under pressures above the magnetic transition from ferromagnetic to paramagnetic phase at ${P}_{\text{c}}\ensuremath{\approx}7$ GPa. Therefore, the Fe-Fe pairs dominantly contribute to the volume expansion due to the magnetovolume effect. Because a similar magnitude of elongation was observed in the Fe-Fe pairs of a non-Invar Fe-Ni alloy, we conclude that the Invar effect originates from the delicate balance between the number of Fe-Fe pairs and their elongation depending on the magnetization.

Mapping of the local lattice distortion is required to understand the details of the chemical and physical properties of thin films. However, the resolution by the direct microscopic methods was insufficient to detect the local distortion. Here, we have demonstrated that the local distortion of a monatomic film on a substrate is estimated with high resolution using the moire pattern of the topographic scanning tunneling microscopy image. The analysis focused on the apparently low centers of the moire pattern of the hexagonal iron nitride monolayer on the Cu(111) substrate. The local distortion was visualized by estimating the displacement of the experimentally detected center position from the ideal position that is extracted from the adjacent center positions. The map of the local distortion revealed that the subsurface impurities are preferentially located on the largely distorted areas. This approach is widely applicable to other thin films on the substrates.

As a new method to determine the resonance frequency, Rabi-oscillation spectroscopy has been developed. In contrast to the conventional spectroscopy which draws the resonance curve, Rabi-oscillation spectroscopy fits the time evolution of the Rabi oscillation. By selecting the optimized frequency, it is shown that the precision is twice as good as the conventional spectroscopy with a frequency sweep. Furthermore, the data under different conditions can be treated in a unified manner, allowing more efficient measurements for systems consisting of a limited number of short-lived particles produced by accelerators such as muons. We have developed a fitting function that takes into account the spatial distribution of muonium and the spatial distribution of the microwave intensity to apply the new method to ground-state muonium hyperfine structure measurements at zero field. This was applied to the actual measurement data and the resonance frequencies were determined under various conditions. The result of our analysis gives $\nu_{\rm HFS}=4\ 463\ 301.61 \pm 0.71\ {\rm kHz}$, which is the world's highest precision under zero field conditions., Comment: 6 pages, 5 figures

We investigate the spin-flip charge-exchange type nuclear excitations, that are, Gamow-Teller (GT) and isovector-spin-monopole (IVSM) transitions, to explore a possible probe to study the two-neutron correlations in the halo nuclei. A typical light halo nucleus, \(^6\)He, is studied with \(^4\)He (\(\alpha \)) \(+\) two-nucleon (N) three-body model. We show that the IVSM transitions are superior to the GT ones to obtain the information on the structure of \(^{6}\)He: The strong IVSM strengths, which are sensitive to the binding energy of \(^6\)He, are found in the low-lying region below the \(\alpha +\)deuteron (d) threshold, whereas the GT strengths have almost no peak due to small overlap between the wave functions of the ground state of \(^6\)He and the \(\alpha +d\) continuum of \(^6\)Li.

Background A less invasive examination that can estimate endoscopic remission is needed. Intestinal ultrasound (IUS) is a promising option. The bowel wall thickness (BWT) is a widely-accepted objective parameter in IUS to assess colonic inflammation, but BWT is influenced by intestinal peristalsis and the volume of luminal content. A feasible, objective index that is not affected by these factors could improve the diagnostic potential of IUS. The submucosa, which is observed as the third layer of the intestinal wall on IUS, becomes swollen and standing out in the active UC. Given BWT and submucosa thickness (SMT) can be influenced by the peristalsis and luminal content simultaneously, we hypothesized that the ratio of SMT to BWT can be an index for submucosal swelling regardless of those factors and this index can be a new parameter to estimate endoscopic remission. Methods Inclusion criteria were (1) both IUS and endoscopy (sigmoidoscopy or colonoscopy) for UC were performed in Kyorin University Hospital between April 2019 and December 2020 and (2) time-interval between IUS and endoscopy was within 2 weeks. BWT and SMT were measured based on IUS images for ascending (A/C), transverse (T/C), descending (D/C), and sigmoid colon (S/C), respectively. We defined the submucosa index (SMI) as a percentage of SMT to BWT (Figure 1). When SMT was too thin to be measured, we scored 0 for SMI. The loss of stratification (LOS) was defined as the condition where the submucosa cannot be identified even with BWT > 3 mm (Figure 2). The parts with LOS were considered as inflamed mucosa. Mayo endoscopic subscore (MES) was scored for each part of the colon based on the endoscopic images. MES of 0/1 was defined as the endoscopic remission. Informed consent was obtained in the opt-out method. This study was approved by the Institutional Review Board of Kyorin University School of Medicine (IRB No. 1668). Results In total 68 parts of the colon (A/C: 11, T/C: 12, D/C: 14, and S/C: 31) were analyzed. With ROC analysis with the Youden index, the cutoff value of BWT for endoscopic remission was 3.7 mm (AUC: 0.84). Among the parts without LOS, the cutoff value of SMI for endoscopic remission was 47.9 (AUC: 0.75). The positive predictive value for endoscopic remission of the diagnostic criteria (1) BWT ≤ 3.7 mm, (2) BWT ≤ 3.7 mm and no LOS, (3) SMI ≤ 48 (no LOS), and (4) BWT ≤ 3.7 mm, SMI ≤ 48 (no LOS) was 83.3%, 88.2%, 60.7%, and 93.3%, respectively. The negative predictive value was 88.0%, 88.2%, 90.0%, and 86.8%, respectively. Conclusion Given the feasibility and objectiveness of assessing bowel wall structure, our findings provide “proof of concept” that SMI can be an additional sonographic parameter for endoscopic remission.

Summary: Background: Periodic point prevalence surveys (PPSs) provide a method for assessing changes in healthcare-associated infections (HAIs) and antimicrobial use over time. Following the introduction of an antimicrobial stewardship programme at Nagoya University Hospital (Aichi, Japan) a five-year PPS study was performed to highlight any epidemiological changes. Methods: One-day PPSs were performed annually in July at Nagoya University Hospital. Data on patient characteristics, medical devices, active HAIs and antimicrobial use were collected using a standard data-collection form. Results: A total of 4339 patients were included. Over the five-year study period the median patient age was 62 years, median duration of hospital admission was nine days, 9% of patients had an HAI and 35.2% received at least one antimicrobial. Overall there were 406 HAIs (95% confidence interval, 369–447) with surgical site infection, pneumonia and febrile neutropenia occurring most frequently. Enterobacterales were the most common pathogens (N = 78, 28.6%) and 32.1% were third-generation cephalosporin-resistant. Meropenem was the most frequently prescribed antimicrobial for HAIs. Surgical antimicrobial prophylaxis changed drastically, with shorter durations and a marked reduction in oral cephalosporin use. However, antimicrobials for medical prophylaxis gradually increased. Conclusions: This five-year PPS study shows consistent data for patient background, HAIs and causative pathogens and highlights changes in antimicrobial use during the era of the National Action Plan on Antimicrobial Resistance. To describe the epidemiology of Japanese hospitals by PPS, multicentre PPSs including in community hospitals should be performed annually.

We report a systematic study of Sm valence in the prototypical intermediate valence compound ${\mathrm{SmB}}_{6}$. Sm mean valence ${v}_{\mathrm{Sm}}$ was measured by x-ray absorption spectroscopy as a function of pressure $(1lPl13\phantom{\rule{0.28em}{0ex}}\mathrm{GPa})$ and temperature $(3lTl300\phantom{\rule{0.28em}{0ex}}\mathrm{K})$. Pressure-induced magnetic order was detected above ${P}_{c}=10\phantom{\rule{0.28em}{0ex}}\mathrm{GPa}$ by resistivity measurements. A shift toward the localized $4f$ state with increasing $P$ and/or $T$ is evident from an increase in ${v}_{\mathrm{Sm}}$. However ${v}_{\mathrm{Sm}}$ at ${P}_{c}$ is anomalously far below 3, which differs from the general case of nonmagnetic-magnetic transition in Yb and Ce compounds. From the $T$ dependence of ${v}_{\mathrm{Sm}}(P,T)$, we found that ${v}_{\mathrm{Sm}}(P,T)$ consists of two different characteristic components: One is associated with low-energy electronic correlations involving Kondo-like behavior, and the other is associated with high-energy valence fluctuations.

The formation and growth of Ru–Si islands were observed on a ruthenium-deposited Si(111) surface during successive cycles of heating for 30 s at 1423 K and cooling. Lateral and vertical growth is analysed. The large lattice mismatch of small Ru2Si3 islands with the Si substrate modulates a Volmer–Weber type growth mode. When the islands are large, Ru2Si3 crystals are situated on a metastable buffer layer. Copyright © 2013 John Wiley & Sons, Ltd.

We show a new way to stabilize epitaxial structures against transforming bulk stable phases for Fe thin films on a vicinal Cu(001) surface. Atomically-resolved observations by scanning tunneling microscopy reveal that high-density Cu steps serve as strain relievers for keeping epitaxially-stabilized Fe fcc(001) lattice even at a transient thickness towards the bulk stable bcc(110) lattice. Spectroscopic measurements further clarify the intrinsic electronic properties of the fcc Fe thin film in real space, implying electronic differences between 6 and 7 monolayer thick films induced by the modification of the lattice constant in the topmost layers., Comment: 5 pages, 5 figures

Patients with idiopathic Parkinson’s disease (PD) appear to have reduced capacity for detoxification of certain environmental compounds. The glutathione S-transferases (GSTs) are candidate genes for PD because they are involved in the metabolism of pesticides and cigarette smoke. We investigated the relationship of the seven GST polymorphisms ( GSTM1 deletion, GSTT1 deletion, GSTP1 rs1695, GSTO1 rs4925, GSTO1 rs11191972, GSTO2 rs156697 and GSTO2 rs2297235) and PD risk with special reference to the interaction with pesticide use or cigarette smoking among 238 patients with PD cases and 370 controls in a Japanese population. None of the GST polymorphisms were associated with PD. GSTO1 rs4925 and GSTO2 rs2297235 were found to be in strong linkage disequilibrium ( D ′ = 0.98). Cigarette smoking was significantly associated with decreased risk of PD. However, no interaction of smoking with any of the GST polymorphisms was observed. Self-reported pesticide use was not associated with increased risk of PD. There was no evidence of interaction between self-reported pesticide use and either GST polymorphism. Our results suggest that the tested GST polymorphisms did not play an important role in PD susceptibility in our Japanese population. Our study does not give evidence of interaction between the GST polymorphisms and smoking may although this study provided sufficient statistical power to detect modest interaction. As for interaction between GSTP polymorphisms and pesticide use, the power of this study to detect an interactive effect was low due to a small number of pesticide users. Future studies involving larger control and case populations and better pesticide exposure histories will undoubtedly lead to a more thorough understanding of the role of the GST polymorphisms in PD development.

The single crystal of the new ternary compound Sm 12 Fe 14 Al 5 was grown and its crystallographic and magnetic properties were investigated. Sm 12 Fe 14 Al 5 has a hexagonal structure of the space group p-3m1 and shows ferromagnetism with a Curie temperature of 245 K. The easy direction of magnetization is parallel to the c -axis at temperatures between 245 and 85 K; however, it changes to the c -plane below 85 K through a first-order-like phase transition. No saturation is observed in the magnetization curve even under the applied field of 55 kOe at 5 K. Sm 12 Fe 14 Al 5 seems to have a large coercive field at very low temperatures. The anisotropy field was estimated at 5 and 120 K and the saturation magnetization of low temperature phase is explained assuming a ferromagnetic coupling between Fe and Sm sublattices.

CaFeO(2), a material exhibiting an unprecedented layered structure containing 3d(6) iron in a high-spin distorted square-planar coordination, is reported. The new phase, obtained through a low-temperature reduction procedure using calcium hydride, has been characterized through powder neutron diffraction, synchrotron X-ray diffraction, Mossbauer spectroscopy, XAS experiments as well as first-principles DFT calculations. The XAS spectra near the Fe-K edge for the whole solid solution (Sr(1-x)Ca(x))FeO(2) supports that iron is in a square-planar coordination for 0/= x/= 0.8 but clearly suggests a change of coordination for x = 1. The new structure contains infinite FeO(2) layers in which the FeO(4) units unprecedentedly distort from square-planar toward tetrahedra and rotate along the c-axis, in marked contrast to the well-studied and accepted concept that octahedral rotation in perovskite oxides occurs but the octahedral shape is kept almost regular. The new phase exhibits high-spin configuration and G-type antiferromagnetic ordering as in SrFeO(2). However, the distortion of the FeO(2) layers leads to only a slight decrease of the Neel temperature with respect to SrFeO(2). First-principles DFT calculations provide a clear rationalization of the structural and physical observations for CaFeO(2) and highlight how the nature of the cation influences the structural details of the AFeO(2) family of compounds (A = Ca, Sr, Ba). On the basis of these calculations the driving force for the distortion of the FeO(2) layers in CaFeO(2) is discussed.

We have studied the effects of swift heavy ion irradiation on the magnetic properties of Fe–50at.%Rh intermetallic compound by using Fe K-edge X-ray magnetic circular dichroism (XMCD) at 20 K. For an unirradiated specimen, no signal of XMCD spectrum has been observed because Fe–50at.%Rh intermetallic compound is intrinsically anti-ferromagnetic below room temperature. For the specimens irradiated with 120–200 MeV Ni, Kr, Xe or Au ions, we have found XMCD spectra which are characterized by a dispersion-type profile with a positive peak and a negative peak near Fe K-edge. The intensity of XMCD spectra remarkably depends on ion-fluence and ion-mass. The experimental result implies that the ferromagnetic state is induced by the swift heavy ion irradiation. The change in magnetic state of Fe element is discussed in terms of energy deposition through the elastic and electronic processes.

Light sedation is preferred for critical ill patients. We often use dexmedetomidine for light sedation, but sometimes additional sedative drugs(such as midazolam and propofol) is needed. Benzodiazepine is risk for delirium, but it is unclear benzodiazepine use combined with dexmedetomidine is risk for delirium.

The local structures around Co and Fe in ${\mathrm{BiCo}}_{1\ensuremath{-}x}{\mathrm{Fe}}_{x}{\mathrm{O}}_{3}$ (BCFO) have been determined element-selectively by means of extended x-ray absorption fine structure (EXAFS) measurements at the Co and Fe $K$ edges. In the tetragonal (T) phase at $x\ensuremath{\le}0.63$, both Fe and Co ions are trivalent and locate in the ${\mathrm{O}}_{5}$ pyramidal coordination. The four in-plane Fe bonds with transverse oxygen (Fe-O2) split into $2\ifmmode\times\else\texttimes\fi{}2$ bonds in the monoclinic (M) phase at $0.63\ensuremath{\le}x\ensuremath{\le}0.73$ whereas the Co-O2 bonds do not show a split exceeding the resolution of our EXAFS analysis. This result is an element-specific interpretation of the polarization rotation in the M phase around the morphotropic phase boundary. The components of thermal vibration and static disorder are evaluated separately from the temperature dependence of the Debye Waller factor from $T=8\phantom{\rule{0.28em}{0ex}}\mathrm{K}$ to 300 K. The static disorder of the Fe site is large compared to that of the Co site, thereby indicating that Fe is unstable in the ${\mathrm{O}}_{5}$ pyramidal coordination of the T and M phases. This study demonstrates that the instability of Fe ions plays an important role in the sequential structural distortion of the BCFO system.

In scanning tunneling microscopy, orbital selectivity of the tunneling process can make the topographic image dependent on a tip-surface distance. We have found reproducible dependence of the images on the distance for a monatomic layer of iron nitride formed on a Cu(001) surface. Observed atomic images systematically change between a regular dot array and a dimerized structure depending on the tip-surface distance, which turns out to be the only relevant parameter in the image variation. An accompanied change in the weight of Fe-3d local density of states to a tunneling background was detected in dI/dV spectra. These have been attributed to a shift in surface orbitals detected by the tip from the d states to the s/p states with increasing the tip-surface distance, consistent with an orbital assignment from first-principles calculations.

Hypercalcemia is relatively rare but clinically important complication in childhood leukemic patients. To clarify the clinical characteristics, mechanisms of hypercalcemia, response to management for hypercalcemia, incidence of t(17;19) and final outcome of childhood acute lymphoblastic leukemia (ALL) accompanied by hypercalcemia, clinical data of 22 cases of childhood ALL accompanied by hypercalcemia (12 mg/dl) reported in Japan from 1990 to 2005 were retrospectively analyzed. Eleven patients were 10 years and older. Twenty patients had low white blood cell count (20 x 10(9)/l), 15 showed hemoglobinor =8 g/dl and 14 showed platelet countor =100 x 10(9)/l. Parathyroid hormone-related peptide (PTHrP)-mediated hypercalcemia was confirmed in 11 of the 16 patients in whom elevated-serum level or positive immunohistochemistry of PTHrP was observed. Hypercalcemia and accompanying renal insufficiency resolved quickly, particularly in patients treated with bisphosphonate. t(17;19) or add(19)(p13) was detected in five patients among 17 patients in whom karyotypic data were available, and the presence of E2A-HLF was confirmed in these five patients. All five patients with t(17;19)-ALL relapsed very early. Excluding the t(17;19)-ALL patients, the final outcome of ALL accompanied by hypercalcemia was similar to that of all childhood ALL patients, indicating that the development of hypercalcemia itself is not a poor prognostic factor.

Magnetism of intermetallic compounds SmFe2, SmFe3, Sm6Fe23, and SmFe7 were studied in detail using single crystals and the use of these materials has been discussed. SmFe2 and Sm6Fe23 have cubic magnetocrystalline anisotropy and the easy axis of magnetization in the [111] direction. SmFe2 has giant negative magnetostriction that can be used for microactuator or ultrasonic generator. SmFe3 has a relatively large saturation moment and uniaxial anisotropy, which are promising for application as a perpendicular magnetic recording medium. Large saturation magnetization and extremely large magnetocrystalline anisotropy of SmFe7 seem promising as an absorber in the frequency range of milliwave as well as a high performance permanent magnet.

On a Cu (001) surface vicinal to a [100] direction, single rows of square patches c(2×2)N in the direction of [010] can be formed on narrow terraces. We deposited Co on the vicinal Cu(001)–c(2×2)N surface, and investigated the magnetic properties of the Co nano-dot array at a temperature range of between 90 and 300 K, using an in situ surface magneto optical Kerr effect. When an average of 1.4 ML of Co was deposited on the surface, rectangular shape hysteresis loops of in-plane magnetization, parallel to the direction of [010], were observed below 130 K. This indicates that the easy magnetization axis is along the step edge.

We have searched for a T/CP violation signature arising from an electric dipole form factor (d_tau) of the tau lepton in the e+e- -> tau+tau- reaction. Using an optimal observable method for 29.5 fb^{-1} of data collected with the Belle detector at the KEKB collider at sqrt{s}=10.58 GeV, we obtained the preliminary result Re(d_tau) = (1.15 +- 1.70) x 10^{-17} ecm and Im(d_tau) = (-0.83 +- 0.86) x 10^{-17} ecm for the real and imaginary parts of d_tau, respectively, and set the 95% confidence level limits -2.2 < Re(d_tau) < 4.5 (10^{-17} ecm) and -2.5 < Im(d_tau) < 0.8 (10^{-17} ecm)., Invited talk at the Seventh International Workshop on Tau Lepton Physics (TAU02), Santa Cruz, Ca, USA, Sept 2002, 8 pages, LaTeX, 19 eps figures

We report on a study of $\bar{B^{0}} \to D^{(*) 0} \pi^+ \pi^-$ decays using 29.1 fb$^{-1}$ of $e^{+}e^{-}$ annihilation data recorded at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB storage ring. Making no assumptions about the intermediate mechanism, the branching fractions for $\bar{B}^0 \to D^0 \pi^+ \pi^-$ and $\bar{B}^0 \to D^{* 0} \pi^+ \pi^-$ are determined to be $(8.0 \pm 0.6 \pm 1.5) \times 10^{-4} $ and $ (6.2 \pm 1.2 \pm 1.8) \times 10^{-4}$ respectively. An analysis of $\bar{B^{0}} \to D^{0} \pi^+ \pi^-$ candidates yields to the first observation of the color-suppressed hadronic decay $\bar{B}^0 \to D^0 \rho^0$ with the branching fraction $(2.9 \pm 1.0 \pm 0.4) \times 10^{-4}$. We measure the ratio of branching fractions ${\mathcal B}(\bar{B^0} \to D^0 \rho^0) / {\mathcal B}(\bar{B^0} \to D^0 \omega)$ = 1.6 $\pm$ 0.8.

We present measurements of CP-violating parameters in $B^0(\bar{B}{}^0) \to \eta^\prime K_S^0$ and $B^{\pm} \to \eta' K^{\pm}$ decays based on a 41.8 fb$^{-1}$ data sample collected at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^{+} e^{-}$ collider. We fully reconstruct one neutral $B$ meson as a $B^0(\bar{B}{}^0) \to \eta^\prime K_S^0$ CP eigenstate and identify the flavor of the accompanying $B$ from its decay products. From the distribution of time intervals between pairs of $B$ meson decay points, we obtain the CP-violating asymmetry parameters ${\mathcal S}_{\eta^\prime K_S^0} = 0.28\pm0.55(stat)^{+0.07}_{-0.08}(syst)$, and ${\mathcal A}_{\eta^\prime K_S^0} = 0.13\pm0.32(stat)^{+0.09}_{-0.06}(syst)$. We also reconstruct charged $B^{\pm} \to \eta^\prime K^{\pm}$ decays and determine a direct-CP violating asymmetry value of ${\mathcal A}_{\eta^\prime K^\pm}=(-1.5\pm7.0(stat)\pm0.9(syst))%$.

This paper describes a study of B meson decays to the pseudoscalar-vector final state \rho\pi using 31.9\times 10^6 B\bar{B} events collected with the Belle detector at KEKB. The branching fractions B(B^+ \to \rho^0\pi^+) = (8.0^{+2.3+0.7}_{-2.0-0.7}) \times 10^{-6} and B(B^0 -> \rho^{+-} \pi^{-+}) = (20.8^{+6.0+2.8}_{-6.3-3.1}) \times 10^{-6} are obtained. In addition, a 90% confidence level upper limit of B(B^0 \to \rho^0\pi^0) < 5.3 \times 10^{-6}is reported.

The production of the \chi_{c2} charmonium state in two-photon collisions has been measured with the Belle detector at the KEKB e^+e^- collider. A clear signal for \chi_{c2} --> \gamma J/\psi, J/\psi --> l^+l^- is observed in a 32.6fb^{-1} data sample accumulated at center-of-mass energies near 10.6GeV, and the product of its two-photon decay width and branching fraction is determined to be \Gamma_{\gamma\gamma}(\chi_{c2})B(\chi_{c2} --> \gamma J/\psi) B(J/\psi --> l^+l^-)= 13.5 +/- 1.3(stat.) +/- 1.1(syst.)eV., Comment: 16 pages, 5 figures, to be submitted to Phys. Lett. B

The formation of induced 5d magnetic moment on Ir in Fe100−x Ir x (x=3, 10 and 17) and Co100−x Ir x (x=5, 17, 25 and 32) alloys has been investigated by X-ray magnetic circular dichroism (XMCD) at Ir L2,3 absorption edges. Sum rule analysis of the XMCD data show that the orbital moment of Ir is in the range of −0.071(2)µB to −0.030(1)µB in Fe-Ir alloys and −0.067(2)µB to 0.024(1)µB in Co-Ir alloys. We find that the total moment of Ir in Fe-Ir alloys is approximately 1/5 of the total 3d moment on Fe at all the three compositions. In contrast, the total moment on Ir in Co-Ir alloys varies between 1/6 to 1/16 of the 3d moment on cobalt. The observed trends of Ir moments and the role of interatomic exchange interactions in 5d moment formation are discussed.

We present a measurement of the branching fraction for the semileptonic B decay B 0 →D + l − ν , where l− can be either an electron or a muon. We find Γ( B 0 →D + l − ν )=(13.79±0.76±2.51) ns −1 , and the resulting branching fraction B ( B 0 →D + l − ν )=(2.13±0.12±0.39)% , where the first error is statistical and the second systematic. We also investigate the B 0 →D + l − ν form factor and the implications of the result for |Vcb|. From a fit to the differential decay distribution we obtain the rate normalization |Vcb|FD(1)=(4.11±0.44±0.52)×10−2. Using a theoretical calculation of FD(1), the Cabibbo–Kobayashi–Maskawa matrix element |Vcb|=(4.19±0.45±0.53±0.30)×10−2 is obtained, where the last error comes from the theoretical uncertainty of FD(1). The results are based on a data sample of 10.2fb−1 recorded at the ϒ(4S) resonance with the Belle detector at the KEKB e+e− collider.

The BELLE detector for experiments at KEKB, a high luminosity, energy asymmetric B-factory, is now being constructed at KEK. An overview of the detector systems and their status is presented.

We present a measurement of the Cabibbo–Kobayashi–Maskawa (CKM) matrix element |Vcb| using a 10.2 fb−1 data sample recorded at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric e+e− storage ring. By extrapolating the differential decay width of the B 0 →D ∗+ e − ν decay to the kinematic limit at which the D ∗+ is at rest with respect to the B 0 , we extract the product of |Vcb| with the normalization of the decay form factor F(1), |Vcb|F(1)=(3.54±0.19±0.18)×10−2, where the first error is statistical and the second is systematic. A value of |Vcb|=(3.88±0.21±0.20±0.19)×10−2 is obtained using a theoretical calculation of F(1), where the third error is due to the theoretical uncertainty in the value of F(1). The branching fraction B ( B 0 →D ∗+ e − ν ) is measured to be (4.59±0.23±0.40)×10−2.

Metal nitride has robust bonding between metal and nitrogen atoms. We have synthesized a monoatomic layer of a hexagonal-type iron nitride with strong Fe-N bond on the Cu(001) substrate with a fourfold lattice symmetry. From atomic-scale observation using scanning tunneling microscopy, we have found that the Fe-N film exhibits a strip structure consisting of regular and deformed hexagonal lattices. The lattices are deformed along a hypothetical Moir\'e pattern made by a perfect hexagonal lattice on the square Cu(001) lattice. With increasing the lattice deformation, the strain energy increases, whereas the periodic deformation of the Fe-N lattice can minimize the total lattice energy including the strain energy of the Fe-N in-plane bonding and interfacial bonding energy between the Fe-N layer and the Cu substrate. In $\mathrm{d}I/\mathrm{d}V$ spectra, periodic spatial change of the unoccupied density of states due to the lattice strain was observed. This is attributed to an energy shift of the antibonding states due to compressive strain.