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The Joint evaluated fission and fusion nuclear data library, JEFF-3.3

Plompen, A. J. M.*; Cabellos, O.*; De Saint Jean, C.*; Fleming, M.*; Algora, A.*; Angelone, M.*; Archier, P.*; Bauge, E.*; Bersillon, O.*; Blokhin, A.*; et al.

European Physical Journal A, 56(7), p.181_1 - 181_108, 2020/07

 被引用回数:3 パーセンタイル:11.65(Physics, Nuclear)

本論文では、核分裂と核融合のための統合評価済み核データファイルのバージョン3.3(JEFF-3.3)について説明する。中性子との反応が重要な核種の$$^{235}$$U, $$^{238}$$U, $$^{239}$$Pu, $$^{241}$$Am, $$^{23}$$Na, $$^{59}$$Ni, Cr, Cu, Zr, Cd, Hf, Au, Pb, Biについて、新しい核データ評価結果を示す。JEFF-3.3には、核分裂収率, 即発核分裂スペクトル, 核分裂平均中性子発生数の新しいデータが含まれる。更に、放射崩壊, 熱中性子散乱, ガンマ線放出, 中性子による放射化, 遅発中性子, 照射損傷に関する新しいデータも含まれている。JEFF-3.3は、TENDLプロジェクトのファイルで補完しており、光子, 陽子, 重陽子, 三重陽子, $$^{3}$$He核, アルファ粒子による反応ライブラリについては、TENDL-2017から採用した。また、不確かさの定量化に対する要求の高まりから、多くの共分散データが新しく追加された。JEFF-3.3を用いた解析の結果と臨界性, 遅発中性子割合, 遮蔽, 崩壊熱に対するベンチマーク実験の結果を比較することにより、JEFF-3.3は幅広い原子核技術の応用分野、特に原子力エネルギーの分野において優れた性能を持っていることが分かった。


Sequential nature of ($$p,3p$$) two-proton knockout from neutron-rich nuclei

Frotscher, A.*; G$'o$mez-Ramos, M.*; Obertelli, A.*; Doornenbal, P.*; Authelet, G.*; 馬場 秀忠*; Orlandi, R.; 他86名*

Physical Review Letters, 125(1), p.012501_1 - 012501_7, 2020/07

Twenty-one two-proton ($$p,3p$$) knock-out cross sections of neutron-rich radioactive isotopes were measured in inverse kinematics using the MINOS time-projection chamber at RIBF, RIKEN. The proton angular distributions, measured for the first time, reveal that the reaction kinematics of the ($$p,3p$$) reaction is consistent with sequential proton collisions within the projectile nucleus.


Evidence for magnon-phonon coupling in the topological magnet Cu$$_{3}$$TeO$$_{6}$$

Bao, S.*; Cai, Z.*; Si, W.*; Wang, W.*; Wang, X.*; Shangguan, Y.*; Ma, Z.*; Dong, Z.-Y.*; 梶本 亮一; 池内 和彦*; et al.

Physical Review B, 101(21), p.214419_1 - 214419_8, 2020/06

 被引用回数:0 パーセンタイル:100(Materials Science, Multidisciplinary)

We perform thermodynamic and inelastic neutron scattering (INS) measurements to study the lattice dynamics (phonons) of a cubic collinear antiferromagnet Cu$$_{3}$$TeO$$_{6}$$ which hosts topological spin excitations (magnons). While the specific heat and thermal conductivity results show that the thermal transport is dominated by phonons, the deviation of the thermal conductivity from a pure phononic model indicates that there is a strong coupling between magnons and phonons. In the INS measurements, we find a mode in the excitation spectra at 4.5 K, which exhibits a slight downward dispersion around the Brillouin zone center. This mode disappears above the N$'{e}$el temperature and thus cannot be a phonon. Furthermore, the dispersion is distinct from that of a magnon. Instead, it can be explained by the magnon-polaron mode, collective excitations resulting from the hybridization between magnons and phonons. We consider the suppression of the thermal conductivity and emergence of the magnon-polaron mode to be evidence for magnon-phonon coupling in Cu$$_{3}$$TeO$$_{6}$$.


How different is the core of $$^{25}$$F from $$^{24}$$O$$_{g.s.}$$ ?

Tang, T. L.*; 上坂 友洋*; 川瀬 頌一郎; Beaumel, D.*; 堂園 昌伯*; 藤井 俊彦*; 福田 直樹*; 福永 拓*; Galindo-Uribarri. A.*; Hwang, S. H.*; et al.

Physical Review Letters, 124(21), p.212502_1 - 212502_6, 2020/05

 被引用回数:1 パーセンタイル:100(Physics, Multidisciplinary)

中性子過剰核$$^{25}$$Fの構造が($$p,2p$$)反応で調査した。$$pi 0d_{5/2}$$軌道の分光学的因子は1.0$$pm$$0.3と大きいが、一方で残留核である$$^{24}$$Oが基底状態である割合は約35%,励起状態は約0.65%であることが明らかになった。この結果は、$$^{25}$$Fのコア核$$^{24}$$Oは基底状態とは大きく異なり、$$^{24}$$Oの$$0d_{5/2}$$軌道に陽子がひとつ加わることで$$^{24}$$Oと$$^{25}$$Fの中性子軌道が相当に変化していると推測される。これは酸素同位体ドリップライン異常のメカニズムである可能性がある。


Experimental realization of a passive Gigahertz frequency-division demultiplexer for magnonic logic networks

Heussner, F.*; Talmelli, G.*; Geilen, M.*; Heinz, B.*; Br$"a$cher, T.*; Meyer, T.*; Ciubotaru, F.*; Adelmann, C.*; 山本 慧; Serga, A. A.*; et al.

Physica Status Solidi; Rapid Research Letters, 14(4), p.1900695_1 - 1900695_6, 2020/04

 被引用回数:3 パーセンタイル:12.53(Materials Science, Multidisciplinary)

The emerging field of magnonics employs spin waves and their quanta, magnons, to implement wave-based computing on the micro- and nanoscales. Multi-frequency magnon networks would allow for parallel data processing within single logic elements whereas this is not the case with conventional transistor-based electric logic. However, a lack of experimental proven solutions to efficiently combine and separate magnons of different frequencies has impeded the intensive use of this concept. In this Letter, the experimental realization of a spin-wave demultiplexer enabling frequency-dependent separation of magnetic signals in the GHz range is demonstrated. The device is based on two-dimensional magnon transport in the form of spin-wave beams in unpatterned magnetic films. The intrinsic frequency-dependence of the beam direction is exploited to realize a passive functioning obviating an external control and additional power consumption. This approach paves the way to magnonic multiplexing circuits enabling simultaneous information transport and processing.


Shell structure of the neutron-rich isotopes $$^{69,71,73}$$Co

Lokotko, T.*; Leblond, S.*; Lee, J.*; Doornenbal, P.*; Obertelli, A.*; Poves, A.*; Nowacki, F.*; 緒方 一介*; 吉田 数貴; Authelet, G.*; et al.

Physical Review C, 101(3), p.034314_1 - 034314_7, 2020/03

 被引用回数:0 パーセンタイル:100(Physics, Nuclear)

中性子過剰核である$$^{69,71,73}$$Coに対する($$p,2p$$)ノックアウト反応が理化学研究所RIBFで測定された。$$gamma-gamma$$ coincidenceの方法で準位構造が決定され、測定された包括的断面積および排他的断面積から暫定的ではあるがスピン・パリティが決定された。殻模型計算との比較により、$$^{69,71,73}$$Coの低励起状態には球形核と変形核が共存することが示唆された。


Restoration of the natural $$E(1/2^+_1)-E(3/2^+_1)$$ energy splitting in odd-K isotopes towards $$N=40$$

Sun, Y. L.*; Obertelli, A.*; Doornenbal, P.*; Barbieri, C.*; 茶園 亮樹*; Duguet, T.*; Liu, H. N.*; Navr$'a$til, P.*; Nowacki, F.*; 緒方 一介*; et al.

Physics Letters B, 802, p.135215_1 - 135215_7, 2020/03

 被引用回数:2 パーセンタイル:27.79(Astronomy & Astrophysics)

カリウムは陽子数が19であるため、その$$1/2^+_1$$, $$3/2^+_1$$状態はそれぞれ陽子の$$s_{1/2}$$, $$d_{3/2}$$軌道の空孔状態によって支配されている。その中性子数を$$N=20$$から増やすとこの2つの準位のエネルギー差$$E(1/2^+_1)-E(3/2^+_1)$$は大きく変化することが知られており、中性子過剰核における殻進化と呼ばれる現象のプロトタイプとなっている。これまで$$E(1/2^+_1)-E(3/2^+_1)$$$$N=30$$まで知られていたが、この研究では、理化学研究所RIビームファクトリーにて、カルシウム同位体からの陽子ノックアウト反応によって$$^{51,53}$$Kの励起状態を生成し、そこからの脱励起ガンマ線を測定することによって、$$N=32, 34$$における$$E(1/2^+_1)-E(3/2^+_1)$$を測定することに成功した。歪曲波インパルス近似計算と実験で得られた断面積の比較から、$$1/2^+_1$$, $$3/2^+_1$$状態は空孔状態によって支配されていることを確かめた。$$E(1/2^+_1)-E(3/2^+_1)$$の値は$$N=28$$で最小となり、そこから中性子数を増やすとともに増大することがわかった。これは、中心力とテンソル力による殻進化描像にしたがった振る舞いである。


Clades of huge phages from across Earth's ecosystems

Al-Shayeb, B.*; Sachzdeva, R.*; Chen, L.-X.*; Ward, F.*; Munk, P.*; Devoto, A.*; Castelle, C. J.*; Olm, M. R.*; Bouma-Gregson, K.*; 天野 由記; et al.

Nature, 578(7795), p.425 - 431, 2020/02

 被引用回数:20 パーセンタイル:0.48(Multidisciplinary Sciences)

Phage typically have small genomes and depend on their bacterial hosts for replication. We generated metagenomic datasets from many diverse ecosystems and reconstructed hundreds of huge phage genomes, between 200 kbp and 716 kbp in length. Thirty four genomes were manually curated to completion, including the largest phage genomes yet reported. Expanded genetic repertoires include diverse and new CRISPR-Cas systems, tRNAs, tRNA synthetases, tRNA modification enzymes, initiation and elongation factors and ribosomal proteins. Phage CRISPR have the capacity to silence host transcription factors and translational genes, potentially as part of a larger interaction network that intercepts translation to redirect biosynthesis to phage-encoded functions. Some phage repurpose bacterial systems for phage-defense to eliminate competing phage. We phylogenetically define seven major clades of huge phage from human and other animal microbiomes, oceans, lakes, sediments, soils and the built environment. We conclude that large gene inventories reflect a conserved biological strategy, observed across a broad bacterial host range and resulting in the distribution of huge phage across Earth's ecosystems.


Ultralow thermal conductivity from transverse acoustic phonon suppression in distorted crystalline $$alpha$$-MgAgSb

Li, X.*; Liu, P.-F.*; Zhao, E.*; Zhang, Z.*; Guide, T.*; Le, M. D.*; Avdeev, M.*; 池田 一貴*; 大友 季哉*; 古府 麻衣子; et al.

Nature Communications (Internet), 11(1), p.942_1 - 942_9, 2020/02

 被引用回数:2 パーセンタイル:28.87(Multidisciplinary Sciences)



Strong local moment antiferromagnetic spin fluctuations in V-doped LiFeAs

Xu, Z.*; Dai, G.*; Li, Y.*; Yin, Z.*; Rong, Y.*; Tian, L.*; Liu, P.*; Wang, H.*; Xing, L.*; Wei, Y.*; et al.

npj Quantum Materials (Internet), 5(1), p.11_1 - 11_7, 2020/02

 被引用回数:1 パーセンタイル:26.04(Materials Science, Multidisciplinary)

We use neutron scattering to study Vanadium (hole)-doped LiFe$$_{1-x}$$V$$_{x}$$As. In the undoped state, LiFeAs exhibits superconductivity at $$T_mathrm{c} = 18$$ K and transverse incommensurate spin excitations similar to electron overdoped iron pnictides. Upon Vanadium doping to form LiFe$$_{0.955}$$V$$_{0.045}$$, the transverse incommensurate spin excitations in LiFeAs transform into longitudinally elongated ones in a similar fashion to that of potassium (hole)-doped Ba$$_{0.7}$$K$$_{0.3}$$Fe$$_{2}$$As$$_{2}$$ but with dramatically enhanced magnetic scattering and elimination of superconductivity. This is different from the suppression of the overall magnetic excitations in hole-doped BaFe$$_{2}$$As$$_{2}$$ and the enhancement of superconductivity near optimal hole doping. These results are consistent with density function theory plus dynamic mean field theory calculations, suggesting that Vanadium doping in LiFeAs may induce an enlarged effective magnetic moment $$S_mathrm{eff}$$ with a spin crossover ground state arising from the inter-orbital scattering of itinerant electrons.


Shell evolution of $$N$$ = 40 isotones towards $$^{60}$$Ca; First spectroscopy of $$^{62}$$Ti

Cort$'e$s, M. L.*; Rodriguez, W.*; Doornenbal, P.*; Obertelli, A.*; Holt, J. D.*; Lenzi, S. M.*; Men$'e$ndez, J.*; Nowacki, F.*; 緒方 一介*; Poves, A.*; et al.

Physics Letters B, 800, p.135071_1 - 135071_7, 2020/01

 被引用回数:2 パーセンタイル:11.68(Astronomy & Astrophysics)

ガンマ線分光による$$N$$=40同調体である$$^{62}$$Tiの分光学研究を$$^{63}$$V($$p$$,$$2p$$)$$^{62}$$TiをRIBFで行った。今回初めて測定された$$2_1^+ rightarrow 0_{rm gs}^+$$$$4_1^+ rightarrow 2_1^+$$の遷移はTiの基底状態が変形していることを示唆した。これらのエネルギーは近傍核の$$^{64}$$Crや$$^{66}$$Feと比較して大きく、したがって四重極集団運動が小さくなっていることが示唆される。今回の結果は大規模殻模型計算によって良く再現される一方、第一原理計算や平均場模型では今回の結果は再現されなかった。


Fine structure in the $$alpha$$ decay of $$^{223}$$U

Sun, M. D.*; Liu, Z.*; Huang, T. H.*; Zhang, W. Q.*; Andreyev, A. N.; Ding, B.*; Wang, J. G.*; Liu, X. Y.*; Lu, H. Y.*; Hou, D. S.*; et al.

Physics Letters B, 800, p.135096_1 - 135096_5, 2020/01

 被引用回数:1 パーセンタイル:27.79(Astronomy & Astrophysics)

Fine structure in the $$alpha$$ decay of $$^{223}$$U was observed in the fusion-evaporation reaction $$^{187}$$Re($$^{40}$$Ar,p3n) by using fast digital pulse processing technique. Two $$alpha$$-decay branches of $$^{223}$$U feeding the ground state and 244 keV excited state of $$^{219}$$Th were identified by establishing the decay chain $$^{223}$$U$$rightarrow$$$$^{219}$$Th$$rightarrow$$$$^{215}$$Ra$$rightarrow$$$$^{211}$$Rn. The $$alpha$$-particle energy for the ground-state to ground-state transition of $$^{223}$$U was determined to be 8993(17) keV, 213 keV higher than the previous value, the half-life was updated to be 62$$^{+14}_{-10} mu$$s. Evolution of nuclear structure for $$N$$=131 even-$$Z$$ isotones from Po to U was discussed in the frameworks of nuclear mass and reduced $$alpha$$-decay width, a weakening octupole deformation in the ground state of $$^{223}$$U relative to its lighter isotones $$^{219}$$Ra and $$^{211}$$Th was suggested.


Measurements of the branching fractions $${cal B}(B^{-} to bar{Lambda}_{c}^{-} Xi_{c}^{'0})$$, $${cal B}(B^{-} to bar{Lambda}_{c}^{-} Xi_{c}(2645)^{0})$$ and $${cal B}(B^{-} to bar{Lambda}_{c}^{-} Xi_{c}(2790)^{0})$$

Li, Y.*; 谷田 聖; Belle Collaboration*; 他175名*

Physical Review D, 100(11), p.112010_1 - 112010_8, 2019/12

 被引用回数:0 パーセンタイル:100(Astronomy & Astrophysics)

Using the data sample of 711 fb$$^{-1}$$ of $$Upsilon(4S)$$ on-resonance data taken by the Belle detector at the KEKB asymmetric-energy electron-positron collider, we present the first measurements of branching fractions of the decays $$B^{-} to bar{Lambda}_{c}^{-} Xi_{c}^{'0}$$, $$B^{-} to bar{Lambda}_{c}^{-} Xi_{c}(2645)^{0}$$, and $$B^{-} to bar{Lambda}_{c}^{-} Xi_{c}(2790)^{0}$$. The signal yields for these decays are extracted from the recoil mass spectrum of the system recoiling against $$bar{Lambda}_{c}^{-}$$ baryons in selected $$B^-$$ candidates. The branching fraction of $$B^{-} to bar{Lambda}_{c}^{-} Xi_{c}(2790)^{0}$$ is measured to be $$(1.1 pm 0.4 pm 0.2)times 10^{-3}$$, where the first uncertainty is statistical and the second is systematic. The 90% credibility level upper limits on $${cal B}(B^{-} to bar{Lambda}_{c}^{-} Xi_{c}^{'0})$$ and $${cal B}(B^{-} to bar{Lambda}_{c}^{-} Xi_{c}(2645)^{0})$$ are determined to be $$6.5times 10^{-4}$$ and $$7.9times 10^{-4}$$, respectively.


$$alpha$$-decay properties of $$^{200,202}$$Fr

Ghys, L.*; Andreyev, A. N.; Huyse, M.*; Van Duppen, P.*; Antalic, S.*; Barzakh, A.*; Capponi, L.*; Cocolios, T. E.*; Cubiss, J.*; Derkx, X.*; et al.

Physical Review C, 100(5), p.054310_1 - 054310_13, 2019/11

 被引用回数:4 パーセンタイル:16.29(Physics, Nuclear)

The aim of this work was to investigate the $$alpha$$-decay properties of $$^{200,202}$$Fr and daughter products. Neutron-deficient francium nuclei are produced at ISOLDE-CERN bombarding a UCx target with 1.4 GeV protons. Due to the very high statistics and the high beam purity, improved decay data for $$^{202}$$Fr and its daughters were obtained. The observation of crossover transitions positioned the isomeric high-spin level of $$^{198}$$At at an excitation energy of 265(3) keV. Half-life values of 4.47(5) s and 1.28(10) s were extracted for the ground state and isomeric state of $$^{198}$$At and 52(3) ms for the ground-state decay of $$^{200}$$Fr.


Azimuthal asymmetries of back-to-back $$pi^pm-(pi^0,eta,pi^pm)$$ pairs in $$e^+e^-$$ annihilation

Li, H.*; 谷田 聖; Belle Collaboration*; 他131名*

Physical Review D, 100(9), p.092008_1 - 092008_26, 2019/11

 被引用回数:2 パーセンタイル:74.49(Astronomy & Astrophysics)

This work reports the first observation of azimuthal asymmetries around the thrust axis in $$e^+e^-$$ annihilation of pairs of back-to-back charged pions in one hemisphere, and $$pi^0$$ and $$eta$$ mesons in the opposite hemisphere. These results are complemented by a new analysis of pairs of back-to-back charged pions. The $$pi^0$$ and $$eta$$ asymmetries rise with the relative momentum $$z$$ of the detected hadrons as well as with the transverse momentum with respect to the thrust axis. These asymmetries are sensitive to the Collins fragmentation function $$H_1^{perp}$$ and provide complementary information to previous measurements with charged pions and kaons in the final state. In particular, the $$eta$$ final states will provide additional information on the flavor structure of $$H_1^{perp}$$. This is the first measurement of the explicit transverse-momentum dependence of the Collins fragmentation function from Belle data. It uses a dataset of 980.4 fb$$^{-1}$$ collected by the Belle experiment at or near a center-of-mass energy of 10.58 GeV.


Comparison of heavy-ion transport simulations; Collision integral with pions and $$Delta$$ resonances in a box

小野 章*; Xu, J.*; Colonna, M.*; Danielewicz, P.*; Ko, C. M.*; Tsang, M. B.*; Wang, Y,-J.*; Wolter, H.*; Zhang, Y.-X.*; Chen, L.-W.*; et al.

Physical Review C, 100(4), p.044617_1 - 044617_35, 2019/10

 被引用回数:13 パーセンタイル:2.33(Physics, Nuclear)



Quasifree neutron knockout from $$^{54}$$Ca corroborates arising $$N=34$$ neutron magic number

Chen, S.*; Lee, J.*; Doornenbal, P.*; Obertelli, A.*; Barbieri, C.*; 茶園 亮樹*; Navr$'a$til, P.*; 緒方 一介*; 大塚 孝治*; Raimondi, F.*; et al.

Physical Review Letters, 123(14), p.142501_1 - 142501_7, 2019/10

 被引用回数:6 パーセンタイル:18.18(Physics, Multidisciplinary)

$$^{54}$$Caでは中性子魔法数34が現れると考えられているが、その直接的な実験的証拠を得るため、$$^{54}$$Caからの中性子ノックアウト反応$$^{54}$$Ca($$p,pn$$)$$^{53}$$Caによって生成される状態を理化学研究所のRI Beam Factoryによって調べた。基底状態および2.2MeVの励起状態が強く生成され、1.7MeVの励起状態の生成量は小さかった。$$^{53}$$Caの運動量分布から、基底状態および2.2MeVの励起状態は$$p$$軌道の中性子を叩き出して得られた状態であることが明らかになった。DWIA計算によって得られた分光学的因子から、$$^{54}$$Caは$$p$$軌道がほぼ完全に占有された閉殻構造を持つことが明らかになり、中性子魔法数34の出現が確実なものとなった。


Electromagnetic properties of low-lying states in neutron-deficient Hg isotopes; Coulomb excitation of $$^{182}$$Hg, $$^{184}$$Hg, $$^{186}$$Hg and $$^{188}$$Hg

Wrzosek-Lipska, K.*; Rezynkina, K.*; Bree, N.*; Zieli$'n$ska, M.*; Gaffney, L. P.*; Petts, A.*; Andreyev, A. N.; Bastin, B.*; Bender, M.*; Blazhev, A.*; et al.

European Physical Journal A, 55(8), p.130_1 - 130_23, 2019/08

 被引用回数:5 パーセンタイル:11.46(Physics, Nuclear)

The neutron-deficient mercury isotopes serve as a classical example of shape coexistence, whereby at low energy near-degenerate nuclear states characterized by different shapes appear. The electromagnetic structure of even-mass $$^{182-188}$$Hg isotopes was studied using safe-energy Coulomb excitation of neutron-deficient mercury beams delivered by the REX-ISOLDE facility at CERN. The population of 0$$^{+}_{1,2}$$, 2$$^{+}_{1,2}$$, and 4$$^{+}_{1}$$ states was observed in all nuclei under study. Reduced $$E2$$ matrix elements coupling populated yrast and non-yrast states were extracted, including their relative signs. These are a sensitive probe of shape coexistence and may be used to validate nuclear models. The experimental results are discussed in terms of mixing of two different configurations and are compared with three different model calculations: the Beyond Mean Field model, the Interacting Boson Model with configuration mixing and the General Bohr Hamiltonian. Partial agreement with experiment was observed, hinting to missing ingredients in the theoretical descriptions.


Isomer spectroscopy in $$^{133}$$Ba and high-spin structure of $$^{134}$$Ba

Kaya, L.*; Vogt, A.*; Reiter, P.*; Siciliano, M.*; 清水 則孝*; 宇都野 穣; Wang, H.-K.*; Gargano, A.*; Coraggio, L.*; Itaco, N.*; et al.

Physical Review C, 100(2), p.024323_1 - 024323_18, 2019/08

 被引用回数:1 パーセンタイル:60.45(Physics, Nuclear)



First measurements of absolute branching fractions of the $$Xi_c^+$$ baryon at Belle

Li, Y. B.*; 谷田 聖; Belle Collaboration*; 他194名*

Physical Review D, 100(3), p.031101_1 - 031101_8, 2019/08

 被引用回数:9 パーセンタイル:14.52(Astronomy & Astrophysics)

We present the first measurements of the absolute branching fractions of $$Xi_c^+$$ decays into $$Xi^- pi^+ pi^+$$ and $$p K^- pi^+$$ final states. Our analysis is based on a data set of $$(772pm 11)times 10^{6}$$ $$Bbar{B}$$ pairs collected at the $$Upsilon(4S)$$ resonance with the Belle detector at the KEKB $$e^+e^-$$ collider. We measure the absolute branching fraction of $$bar{B}^{0} to bar{Lambda}_{c}^{-} Xi_{c}^{+}$$ with the $$Xi_c^+$$ recoiling against $$bar{Lambda}_c^-$$ in $$bar{B}^0$$ decays resulting in $${cal B}(bar{B}^{0} to bar{Lambda}_{c}^{-} Xi_{c}^{+}) = [1.16 pm 0.42(rm stat.) pm 0.15(rm syst.)] times 10^{-3}$$. We then measure the product branching fractions $${cal B}(bar{B}^{0} to bar{Lambda}_c^- Xi_c^+){cal B}(Xi_c^+ to Xi^- pi^+ pi^+)$$ and $${cal B}(bar{B}^{0} to bar{Lambda}_c^- Xi_c^+){cal B}(Xi_c^+ to p K^- pi^+)$$. Dividing these product branching fractions by $$bar{B}^{0} to bar{Lambda}_{c}^{-} Xi_{c}^{+}$$ yields: $${cal B}(Xi_c^+ to Xi^- pi^+ pi^+) = [2.86 pm 1.21(rm stat.) pm 0.38(rm syst.)]%$$ and $${cal B}(Xi_c^+ to p K^- pi^+)=[0.45 pm 0.21(rm stat.) pm 0.07(rm syst.)]%$$. Our result for $${cal B}(Xi_c^+ to Xi^- pi^+ pi^+)$$ can be combined with $$Xi_c^+$$ branching fractions measured relative to $$Xi_c^+ to Xi^- pi^+ pi^+$$ to set the absolute scale for many $$Xi_c^+$$ branching fractions.

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