Novel c.2216T > C (p.I739T) Mutation in Exon 13 and c.1481T > A (p.L494X) Mutation in Exon 8 of MUT Gene in a Female with Methylmalonic Acidemia

We report herein a 1.5-year-old girl with methylmalonic acidemia (MMA) in whom two missense mutations were found: a novel I739T mutation located in exon 13 and the L494X mutation in exon 8. The results of organic acid test showed a pronounced increase in methylmalonate excretion with increased methylcitrate and 3-OH-propionate excretion, leading to a diagnosis of MMA, and Vitamin B12 administration was started. Analysis of the mut gene confirmed a T-to-A substitution at nucleotide position 1481 in exon 8 and a T-to-C substitution at nucleotide position 2216 in exon 13, leading to the amino acid isoleucine at position 739 being changed to threonine, resulting in c.2216T > C (p.I739T). The patient has now been on high-dose oral administration of Vitamin B12 and carnitine therapy (900 mg of levocarnitine chloride) for 5 years without experiencing further attacks, and her cognitive and motor development is normal. Further tests on residual enzyme activity, as well as experience with more cases, may shed light on the relationship between gene mutations and phenotypes in MMA

Time-Dependent CP Asymmetries in B0 -> Ks pi0 gamma transitions

We report measurements of CP violation parameters in B0->Ks pi0 gamma transitions based on a data sample of 535x10^6 BB pairs collected with the Belle detector at the KEKB asymmetric-energy e+ e- collider. One neutral B meson is fully reconstructed in the B0->Ks pi0 gamma mode. The flavor of the accompanying B meson is identified from its decay products. For a Ks pi0 invariant mass up to 1.8 GeV/c^2, we obtain S = -0.10 +- 0.31 +- 0.07 and A = -0.20 +- 0.20 +- 0.06. For a Ks pi0 invariant mass near the K*0(892) resonance, we obtain S = -0.32 +0.36-0.33 +-0.05 and A=-0.20 +-0.24 +-0.05.Comment: 6 pages, 3 figures, accepted by PR

Observation of B0ˉ\bar{B^0} -> DsJ*(2317)+ K- decay

The decays $\bar{B^0} \to D_{sJ}^+ K^-$ and $\bar{B^0} \to D_{sJ}^- \pi^+$ are studied for the first time. A significant signal is observed in the $\bar{B^0} \to D_{sJ}^*(2317)^+ K^-$ decay channel with ${\cal B}(\bar{B^0} \to D_{sJ}^*(2317)^+ K^-) \times {\cal B} (D_{sJ}^*(2317)^+ \to D_s^+ \pi^0) = (5.3^{+1.5}_{-1.3} \pm 0.7 \pm 1.4) \times 10^{-5}$. No signals are observed in the $\bar{B^0} \to D_{sJ}^*(2317)^- \pi^+$, $\bar{B^0} \to D_{sJ}(2460)^+ K^-$ and $\bar{B^0} \to D_{sJ}(2460)^- \pi^+$ decay modes, and upper limits are obtained. The analysis is based on a dataset of 140 fb$^{-1}$ collected by the Belle experiment at the asymmetric $e^+ e^-$ collider KEKB.Comment: 9 pages, 2 figures, submitted to PR

Study of time-dependent CP violation in B0 -> J/Psi pi0 decays

We report a measurement of CP asymmetry parameters in the decay B0(B0bar) -> J/Psi pi0, which is governed by the b->c cbar d transition. The analysis is based on a 140/fb data sample accumulated at the Upsilon(4S) resonance by the belle detector at the KEKB asymmetric-energy e+e- collider. We fully reconstruct one neutral B meson in the J/Psi pi0 final state. The accompanying B meson flavor is identified by its decay products. From the distribution of proper time intervals between the two B decays, we obtain the following CP-violating parameters: S_{J/Psi pi0}=-0.72+-0.42+-0.09 and A_{J/Psi pi0}=-0.01 +-0.29+-0.03.Comment: 5 pages, 2 figures, submitted to PR

Spectra of prompt electrons from decays of B+ and B0 mesons and ratio of inclusive semielectronic branching fractions

We present spectra of prompt electrons from decays of neutral and charged B mesons. The results are based on 140 /fb of data collected by the Belle detector on the Upsilon(4S) resonance at the KEKB e+e- asymmetric collider. We tag Upsilon(4S) -> B \bar{B} events by reconstructing a B meson in one of several hadronic decay modes; the semileptonic decay of the other B meson is inferred from the presence of an identified electron. We obtain for charged and neutral B mesons the partial rates of semileptonic decay, to electrons with momentum greater than 0.6 GeV/c in the B rest frame, and their ratio b_+/b_0 = 1.08 +- 0.05 +- 0.02, where the first and second errors are statistical and systematic, respectively.Comment: 16 pages, 2 figure files, submitted to Phys. Lett.

Observation of B0→D+D−B^0 \to D^+ D^-, B−→D0D−B^- \to D^0 D^- and B−→D0D∗−B^- \to D^0 D^{*-} decays

We report the first observation of the decay modes $B^0 \to D^+ D^-$, $B^- \to D^0 D^-$ and $B^- \to D^0 D^{*-}$ based on 152 $\times$ 10$^6$ $B\bar{B}$ events collected at KEKB. The branching fractions of $B^0 \to D^+ D^-$, $B^- \to D^0 D^-$ and $B^- \to D^0 D^{*-}$ are found to be $(3.21 \pm 0.57 \pm 0.48) \times 10^{-4}$, $(5.62 \pm 0.82 \pm 0.65) \times 10^{-4}$ and $(4.59 \pm 0.72 \pm 0.56) \times 10^{-4}$, respectively. Charge asymmetries in the $B^- \to D^0 D^-$ and $B^- \to D^0 D^{*-}$ channels are consistent with zero.Comment: 9 pages, 2 figures, KEK Preprint 2004-99, Belle Prerpint 2005-3, submitted to PR

Observation of the decay B0→J/ψηB^0 \to J/\psi \eta

We report the first observation of $B^0 \to J/\psi \eta$ decay. These results are obtained from a data sample that contains 449 million $B\bar{B}$ pairs accumulated at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+ e^-$ collider. We observe a signal with a significance of 8.1$\sigma$ and obtain a branching fraction of (9.5 $\pm$ 1.7 (stat) $\pm$ 0.8 (syst))$\times 10^{-6}$.Comment: 5 pages, 2 figures, submit to PRL (8 pages, 2 figures, ICHEP'06 Conference Paper

Observation of B Decays to Two Kaons

Using 449 million BBbar pairs collected with the Belle detector at the KEKB asymmetric-energy e^+e^- collider, we observe clear signals for B^+-> \bar{K}^0 K^+ and B^0-> \bar{K}^0 K^0 decays with 5.3 sigma and 6.0 sigma significance, respectively. We measure the branching fractions Br(B^+-> \bar{K}^0 K^+ = (1.22^{+0.32+0.13}_{-0.28-0.16})x10^{-6} and Br(B^0-> \bar{K}^0 K^0) = (0.87^{+0.25}_{-0.20} +- 0.09)x10^{-6}, and partial-rate asymmetries A_{CP}(B^+-> \bar{K}^0 K^+) = 0.13^{+0.23}_{-0.24}+- 0.02 and A_{CP}(B^0-> \bar{K}^0 K^0) = -0.58^{+0.73}_{-0.66}+- 0.04. From a simultaneous fit we also obtain Br(B^+-> K^0\pi^+)= (22.8^{+0.8}_{-0.7} +- 1.3)x 10^{-6} and A_{CP}(B^+-> K^0 \pi^+) = 0.03 +- 0.03 +- 0.01. The first and second error in the branching fractions and the partial-rate asymmetries are statistical and systematic, respectively. No signal is observed for B^0-> K^+ K^- decays, and for this branching fraction we set an upper limit of 4.1x10^{-7} at the 90% confidence level.Comment: 6 pages, 3 figure

Measurement of Branching Fraction and Direct CP Asymmetry in B0-->rho0 pi0 Decays

We report a measurement of the decay B0 --> rho0 pi0, using 386 x 10^6 BB-bar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We detect 51^{+14}_{-13} signal events with a significance of 4.2 standard deviations, including systematic uncertainties, and measure the branching fraction to be B(B0 --> rho0 pi0) = (3.12^{+0.88}_{-0.82} (stat) +/- 0.33 (syst) ^{+0.50}_{-0.68} (model)) x 10^{-6}. We also perform the first measurement of direct CP violating asymmetry in this mode.Comment: 5 pages, 2 figures, accepted in Physical Review

Evidence for Direct CP Violation in B0 -> K+- pi-+ Decays

We report evidence for direct CP violation in the decay B0 -> K+-pi-+ with 253/fb of data collected with the Belle detector at the KEKB e+e- collider. Using 275 million B B_bar pairs we observe a B -> K+-pi-+ signal with 2140+-53 events. The measured CP violating asymmetry is Acp(K+-pi-+) = -0.101+-0.025 (stat)+-0.005 (syst), corresponding to a significance of 3.9 sigma including systematics. We also search for CP violation in the decays B+- -> K+-pi0 and B+- -> pi+-pi0. The measured CP violating asymmetries are Acp(K+-pi0) = 0.04+-0.05(stat)+-0.02(syst) and Acp(pi+-pi0) = -0.02+-0.10(stat)+-0.01(syst), corresponding to the intervals -0.05 < Acp(K+-pi0) < 0.13 and -0.18<Acp(pi+-pi0)<0.14 at 90% confidence level.Comment: 9 pages, 3 figures. submitted to Physical Review Letter