80,425 research outputs found
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
First evidence of the B 0 → J / ψ ω decay is found and the B s 0 → J / ψ η and B s 0 → J / ψ η ′ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb -1 collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV. The branching fractions of these decays are measured relative to that of the B 0 → J / ψ ρ 0 decay:frac(B (B 0 → J / ψ ω), B (B 0 → J / ψ ρ 0)) = 0.89 ± 0.19 (stat) - 0.13 + 0.07 (syst),frac(B (B s 0 → J / ψ η), B (B 0 → J / ψ ρ 0)) = 14.0 ± 1.2 (stat) - 1.5 + 1.1 (syst) - 1.0 + 1.1 (frac(f d, f s)),frac(B (B s 0 → J / ψ η ′), B (B 0 → J / ψ ρ 0)) = 12.7 ± 1.1 (stat) - 1.3 + 0.5 (syst) - 0.9 + 1.0 (frac(f d, f s)), where the last uncertainty is due to the knowledge of f d / f s, the ratio of b-quark hadronization factors that accounts for the different production rate of B 0 and B s 0 mesons. The ratio of the branching fractions of B s 0 → J / ψ η ′ and B s 0 → J / ψ η decays is measured to befrac(B (B s 0 → J / ψ η ′), B (B s 0 → J / ψ η)) = 0.90 ± 0.09 (stat) - 0.02 + 0.06 (syst)
Measurement of the CP-violating phase \phi s in Bs->J/\psi\pi+\pi- decays
Measurement of the mixing-induced CP-violating phase phi_s in Bs decays is of prime importance in probing new physics. Here 7421 +/- 105 signal events from the dominantly CP-odd final state J/\psi pi+ pi- are selected in 1/fb of pp collision data collected at sqrt{s} = 7 TeV with the LHCb detector. A time-dependent fit to the data yields a value of phi_s=-0.019^{+0.173+0.004}_{-0.174-0.003} rad, consistent with the Standard Model expectation. No evidence of direct CP violation is found
Observations of Bºs→ψ(2S)η and Bº(s)→ψ(2S)π+π- decays
First observations of the B0s
→ψ(2S)η, B0 →ψ(2S)π
+
π
− and B0s
→ψ(2S)π
+
π
− decays are made
using a dataset corresponding to an integrated luminosity of 1.0 fb−1 collected by the LHCb experiment in
proton–proton collisions at a centre-of-mass energy of
√
s = 7 TeV. The ratios of the branching fractions
of each of the ψ(2S) modes with respect to the corresponding J/ψ decays are
B(B0s
→ψ(2S)η)
÷
B(B0s
→J/ψη)
= 0.83± 0.14 (stat)±0.12 (syst) ±0.02 (B),
;
B(B0→ψ(2S)π
+
π
−
)
÷
B(B0→J/ψπ
+
π
−
)
= 0.56± 0.07 (stat)±0.05 (syst)± 0.01 (B),
;
B(B0s
→ψ(2S)π
+
π
−
)
÷
B(B0s
→J/ψπ
+
π
−
)
= 0.34± 0.04 (stat)±0.03 (syst)± 0.01 (B),
where the third uncertainty corresponds to the uncertainties of the dilepton branching fractions of the J/ψ
and ψ(2S) meson decays
Matthieu Ricci, s. j. et Nicolas Trigault, s. j. Histoire de l'expédition chrétienne du royaume de la Chine, 1582-1610. Introduction par Joseph SHIH, s. j., établissement du texte et annotations par Georges Bessière, tables et index par Joseph Dehergne, s. j. Paris, Désclée de Brouwer, Bellarmin, 1978. In-8°, 744 pages, 8 planches. (Collection Christus, Textes n° 45.)
Elisseeff-Poisle Danielle. Matthieu Ricci, s. j. et Nicolas Trigault, s. j. Histoire de l'expédition chrétienne du royaume de la Chine, 1582-1610. Introduction par Joseph SHIH, s. j., établissement du texte et annotations par Georges Bessière, tables et index par Joseph Dehergne, s. j. Paris, Désclée de Brouwer, Bellarmin, 1978. In-8°, 744 pages, 8 planches. (Collection Christus, Textes n° 45.). In: Bibliothèque de l'école des chartes. 1980, tome 138, livraison 2. pp. 266-267
Measurement of the ratio of prompt χ c to J / ψ production in pp collisions at √s = 7 TeV
The prompt production of charmonium χ c and J / ψ states is studied in proton-proton collisions at a centre-of-mass energy of √s = 7 TeV at the Large Hadron Collider. The χ c and J / ψ mesons are identified through their decays χ c → J / ψ γ and J / ψ → μ + μ - using 36 pb - 1 of data collected by the LHCb detector in 2010. The ratio of the prompt production cross-sections for χ c and J / ψ, σ (χ c → J / ψ γ) / σ (J / ψ), is determined as a function of the J / ψ transverse momentum in the range 2 < p T J / ψ < 15 GeV / c. The results are in excellent agreement with next-to-leading order non-relativistic expectations and show a significant discrepancy compared with the colour singlet model prediction at leading order, especially in the low p T J / ψ region
Measurement of the branching fraction
The B
0
s
→ J/ψK
0
S
branching fraction is measured in a data sample corresponding to 0.41 fb−1
of integrated luminosity collected with the LHCb detector at the LHC. This channel is sensitive to
the penguin contributions affecting the sin 2β measurement from B
0
→ J/ψK
0
S
. The time-integrated
branching fraction is measured to be B(B
0
s
→ J/ψK
0
S
) = (1.83±0.28)×10−5
. This is the most precise
measurement to date
Jembra kuanae Shih, sp. nov.
<i>Jembra kuanae</i> Shih sp. nov. <p>(Figs. 2, 3)</p> <p> <b>Coloration:</b> General color brown (Fig. 2 A). Tegmen without markings (Fig. 2 B); wing hyaline, veins brown, apical area with brown pubescence except apical cells. Two color variations on head (Figs. 2 D, 2E), pronotum and mesoscutellum: dark brown type with irregular dark brown mottles (Fig. 2 E), and yellowish brown type with one obviously inverted and yellowish V-shaped stripe (Fig. 2 D).</p> <p> <b>Structure:</b> Head width: body width: body length= 1:1.6:3.2. Head in ventral view rhombus shaped (Fig. 3 B), as long as wide; head in dorsal view triangular (Fig. 3 A), about 2.6 times as wide as long. Head subequal to pronotum at level of anterior margin, about 1.04:1.0. Frons with a median longitudinal carina and 10 transverse ridges in ventral view (Fig. 3 B). Expanded flagellar base with 4 plate-shaped basiconic sensillae on ventrolateral side. Rostrum nearly extended to apex of middle trochanters. Pronotum width at widest part greater than median length by about 1.5: 1.0. Tegmen densely punctured (Fig. 3 D) with pits about 0.1 mm in diameter; 3 times as long as wide, AM (length of anal margin): PM (length of posterior margin): LT (length of tegmen) = 1.0: 3.0: 3.9. Wing with 3 apical cells (Fig. 3 E). Hind tibia with two lateral spines, distal one about 2.0–2.5 times as long as basal one; apical spines arranged into 2 rows, upper row composed of 11 spines, lower one composed of 12 spines. First hind tarsomere with apical spines arranged in two rows (Figs. 2 C, 3H), upper row composed of 18–21 spines, lower one composed of 7–12 spines.</p> <p> <b>Male Genitalia:</b> Pygofer in lateral view subquadrate (Fig. 3 I), about 1.3 times wider than long; basal margin of pygofer straight downward, then protruding at ventral third; pygofer ventral view oval (Fig. 3 J); dorsal process of pygofer (dp) in lateral view cone like, ventrally directed (Fig. 3 I); ventral process of pygofer (vp) (= genital plate) in lateral view, about 0.7 times longer than posterior margin of pygofer; ventral processes of pygofer in ventral view bilobed, acute at tip and direct mesade (Fig. 3 J). Abdominal segment X cylindrical, subequal to the abdominal tergite of segment XI (XIt) in length. Aedeagus T-shaped (Figs. 3 O–P) in both dorsal and ventral views, joined with basal part and apical winged plate; basal part of aedeagus short in lateral view, cylindrical, and membranous; apical winged plate somewhat hardened; transversely enlarged at caudal view, widest at middle and with a obviously concave gonopore (Fig. 3 N). Genital style triangular, basal part narrow and gradually widening to apex (Figs. 3 K–L).</p> <p> <b>Measurements:</b> Body length (from apex of vertex to tip of tegmen): 3, 7.9 ± 0.2 mm (n =17); Ƥ, 8.5 ± 0.1 mm (n =2); Body width: 3, 3.8 ± 0.3 mm (n =17); Ƥ, 3.9 ± 0.3 mm (n =2).</p> <p> <b>Holotype: Male, TAIWAN</b>, Taichung, Wanfeng Hill, XII. 1984, K. S. Lin & K. C. Chou, Malaise trap; Holotype depository: TARI.</p> <p> <b>Paratypes: TAIWAN</b>, 1 male, Taichung, Wanfeng Hill, II. 1984, K. S. Lin & K. C. Chou, Malaise trap (TARI); 5 males, 1 female, Taichung, Wanfeng Hill, III. 1984, K. S. Lin & K. C. Chou, Malaise trap (TARI); 2 males, Taichung, Wanfeng Hill, V. 1984, K. S. Lin & K. C. Chou, Malaise trap (TARI); 1 male, Taichung, Wanfeng Hill, VII. 1984, K. S. Lin & K. C. Chou, Malaise trap (TARI); 3 males, 1 female, Taichung, Wanfeng Hill, VIII. 1984, K. S. Lin & K. C. Chou, Malaise trap (TARI); 1 male, Taichung, Wanfeng Hill, XII. 1984, K. S. Lin & K. C. Chou, Malaise trap; 1 male, Nantou, Chushan, 24-IX-1999, H. T. Shih (TARI); 1 male, Nantou, Chushan, 24-IX-1999, H. T. Shih (Institute of Zoology, Chinese Academy of Sciences, China); 1 male, Nantou, Chushan, 24-IX-1999, H. T. Shih (Canadian National Collection of Insects, Ottawa, Canada); 1 male, Nantou, Chushan, 24-IX-1999, H. T. Shih (National Museum of Natural Science, Taiwan, ROC.).</p> <p> <b>Etymology:</b> Named for the first author’s mother K. C. Kuan.</p> <p> <b>Distribution:</b> Taiwan.</p> <p> <b>Host plants:</b> Unknown.</p> <p> <b>Remarks:</b> This species can be distinguished easily from other <i>Jembra</i> species by the following characteristics: (1) antenna with 4 plate-shaped basiconic sensillae (Figs. 2 G–H) on the expanded flagellar base; (2) pronotum without obvious lateral carinae, median carina interrupted by some longitudinal wrinkles on the anterior margin (Fig. 3 A); (3) frons with median longitudinal carina (Fig. 3 B); (4) wing with 3 apical cells and without pubescence in apical cells (Fig. 3 E); (5) the first tarsus with apical spines arranged in 2 rows (Figs. 2 C, 3H); (6) the dorsal process of pygofer conical (Fig. 3 I); (7) genital style triangular (Figs. 3 K–L), without distinct slender inner and outer processes; (8) apical portion of aedeagus winged, and each lateral tip of winged portion directed ventrad (Figs. 3 O–P).</p>Published as part of <i>Shih, Hsien-Tzung, Liang, Ai-Ping & Yang, Jeng-Tze, 2009, The genus Jembra Metcalf and Horton from Taiwan with descriptions of two new species and the nymph of J. taiwana sp. nov. (Hemiptera: Cercopoidea: Aphrophoridae), pp. 29-40 in Zootaxa 1979</i> on pages 33-36, DOI: <a href="http://zenodo.org/record/185235">10.5281/zenodo.185235</a>
Measurement of the time-dependent CP asymmetry in B0 -> J/ψ KS0 decays
This Letter reports a measurement of the CP violation observables SJ/ψK0S and CJ/ψK0S in the decay channel B0→J/ψK0S performed with 1.0 fb−1 of pp collisions at s√=7 TeV collected by the LHCb experiment. The fit to the data yields SJ/ψK0S=0.73±0.07(stat)±0.04(syst) and CJ/ψK0S=0.03±0.09(stat)±0.01(syst). Both values are consistent with the current world averages and within
expectations from the Standard Model
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