43,530 research outputs found
Measurement of the ratio of branching fractions B(B0→K∗0γ )/B(B0s→φγ ) and the directCP asymmetry inB 0→K∗0γ
No full textThe ratio of branching fractions of the radiative B decays B0→K⁎0γ and B0s→ϕγ has been measured using an integrated luminosity of 1.0 fb−1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of s√=7TeV. The value obtained is
B(B0→K⁎0γ)B(B0s→ϕγ)=1.23±0.06(stat.)±0.04(syst.)±0.10(fs/fd),
where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for B(B0→K⁎0γ), the branching fraction B(B0s→ϕγ) is measured to be (3.5±0.4)×10−5.
The direct CP asymmetry in B0→K⁎0γ decays has also been measured with the same data and found to be
ACP(B0→K⁎0γ)=(0.8±1.7(stat.)±0.9(syst.))%.
Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations
Branching fraction and CP asymmetry of the decays B+→K0Sπ+ and B+→K0SK+
No full textAn analysis of B+ → K0
Sπ+ and B+ → K0
S K+ decays is performed with the LHCb experiment. The pp
collision data used correspond to integrated luminosities of 1 fb−1 and 2 fb−1 collected at centre-ofmass
energies of
√
s = 7 TeV and
√
s = 8 TeV, respectively. The ratio of branching fractions and the
direct CP asymmetries are measured to be B(B+ → K0
S K+
)/B(B+ → K0
Sπ+
) = 0.064 ± 0.009 (stat.) ±
0.004 (syst.), ACP(B+ → K0
Sπ+
) = −0.022 ± 0.025 (stat.) ± 0.010 (syst.) and ACP(B+ → K0
S K+
) =
−0.21 ± 0.14 (stat.) ± 0.01 (syst.). The data sample taken at
√
s = 7 TeV is used to search for
B+
c
→ K0
S K+ decays and results in the upper limit ( fc · B(B+
c
→ K0
S K+
))/( fu · B(B+ → K0
Sπ+
)) <
5.8 × 10−2 at 90% confidence level, where fc and fu denote the hadronisation fractions of a ¯b
quark
into a B+
c or a B+ meson, respectively
FIGURE 2. Euphorbia telanganensis Sadas., K in Euphorbia telanganensis (Euphorbiaceae), a new species from Eastern Ghats of Telangana, India
No full textFIGURE 2. Euphorbia telanganensis Sadas., K. Prasad & Ramakrishna sp. nov. A. Flowering twig. B. Abaxial surface of leaves. C. Stipule. D, E. Cyathia. F. Limb of glands. G. Staminate florets. H. Pistillate flower. I. Capsule. J. Seeds.Published as part of Sadasivaiah, B., Ramakrishna, A., Prasad, K., Devi, N. Sarojini & Rao, Nirmala Babu, 2022, Euphorbia telanganensis (Euphorbiaceae), a new species from Eastern Ghats of Telangana, India, pp. 283-288 in Phytotaxa 572 (3) on page 286, DOI: 10.11646/phytotaxa.572.3.7, http://zenodo.org/record/732225
Euphorbia telanganensis Sadas., K. Prasad & Ramakrishna 2022, sp. nov.
No full textEuphorbia telanganensis Sadas., K. Prasad & Ramakrishna sp. nov. (Figs 1 & 2) Type:— INDIA. Telangana: Nagarkurnool district, Amrabad Tiger Reserve, Way to Dharavagu, Kollam penta beat, 600 m, 14 August 2020, A . Ramakrishna & B. Sadasivaiah 2217 (holotype: CAL; isotypes: HY, TBGH, BSID). Diagnosis:— Euphorbia telanganensis is morphologically similar to E. jodhpurensis, but differs in having obovate or elliptic-obovate or ovate-elliptic, and abaxially pubescent leaves (vs. oblong to obliquely oblong or oblong to linearoblong, glabrous), 1.5–2.2 mm long peduncle (vs. c. 1 mm long), turbinate involucre (vs. campanulate), ellipsoid glands (vs. rounded), ellipsoid and unequal limb of glands (vs. orbicular and equal), posterior two limbs are shallowly undulate (vs. margins entire), deeply keeled and trigonous capsules (vs. shallowly keeled and subglobose). Description:— Erect annual herb, 30–40 cm tall; latex milky. Stem sympodial, dichotomously branched; branches terete, distally filiform, glabrous, pale green; internodes 2–4 cm long, thickened at nodes; stipules triangular, laciniate, less than 1 mm long. Leaves simple, opposite, unequal; leaves on main stem distinctly or slightly larger than the leaves on branches; petiole 1–2 mm long; lamina 1.2–2.8 × 0.7–1.2 cm, obovate or elliptic-obovate or ovate-elliptic, obtuse or rounded at apex, margins serrulate, base oblique, midrib prominent, veins slightly distinct on adaxial surface, glabrous on adaxial surface, pubescent and silver-green on abaxial surface. Cyathia terminal and axillary, solitary, 3–3.5 mm long; peduncle 1.5–2.2 mm long; involucre 1–1.3 × 0.8–1 mm, turbinate, glabrous, greenish; involucral lobes 5, laciniate; glands 4, ellipsoid, yellowish-green; limb of glands 4, distinctly larger than glands, unequal (2 anterior are small; 2 posterior are large), pinkish-white or white; anterior appendages subentire, 0.5 × 0.5 mm; posterior appendages shallowly undulate, 1.1–1.2 × 1.3–1.4 mm. Staminate florets 12–18, exserted, 0.8–1.2 mm long, bracteate; bract simple, 1.2–1.4 mm long; bracteole laciniate; anther lobes subglobose, dehiscing transversely, yellow. Pistillate flowers 3.1–3.4 × 1–1.2 mm, glabrous, pedicel 1.5–1.8 mm long; ovary tricarpellate; styles 3, free from base, each connate up to middle then bifid, 0.6–0.8 mm long, pale pink; stigmas pale pink. Fruiting pedicels recurved; capsules 2– 2.5 × 3.3–3.5 mm, trigonous, schizocarpic, distinctly keeled, glabrous; cocci obscurely venulose. Seeds 3 per capsule, ecarunculate, 1.8–2 × 1–1.1 mm, oblong-ovoid, tetragonal, transversely and obscurely furrowed, truncate at base, stramineous to brown. Flowering and fruiting:— August to October. Habitat:— Euphorbia telanganensis is found growing in blackish-red soils of dry deciduous forest at an elevation range of 500– 750m.The common associates are Crotalaria medicaginea Lamarck(1786:201), Curcuma pseudomontana Graham (1839: 210), Cymbopogon coloratus (Hooker 1896: 206) Stapf (1906: 321), Eleiotis monophylla Candolle (1825: 348), Heteropogon contortus (Linnaeus 1753: 1045) Palisot de Beauvois (1817: 836), Rhynchosia suaveolens (Linnaeus 1781: 326) Candolle (1825: 387) Distribution:— Apparently endemic to Amrabad Tiger Reserve (Type locality), Telangana, India. Etymology:— The specific epithet refers to the state (Telangana state) of its occurrence. Additional specimens examined:— INDIA. Telangana: Nagarkurnool district, Amrabad Tiger Reserve, Way to Dharavagu, Kollam penta beat, 600 m, 20 August 2020, A . Ramakrishna & B. Sadasivaiah 2225 (paratype: TBGH!); Rasamolabavi, 730 m, 10 October 2021, K . Prasad & B. Sadasivaiah 2298 (paratype: BSID!, TBGH!). Conservation status:— In the present floristic survey we have noticed more than 400 individuals at two localities in the Amrabad Tiger Reserve and further explorations in the adjacent areas are required. Presently, the area is well protected as it falls under the Amrabad Tiger Reserve. Therefore, there is no immediate threat to this species but the habitat is prone to forest fires and grazing. Following the IUCN guidelines version 14 (IUCN, 2019), Euphorbia telanganensis is assessed as Data Deficient (DD). Note:— The new species, Euphorbia telanganensis and its closely allied species E. jodhpurensis display common morphological characters like small erect herbs, stem dichotomously branched, stipules interpetiolar and laciniate, leaves on main stem distinctly or slightly larger than the leaves on branches, base oblique, dark green on adaxial and silvery green on abaxial surface, presence of petaloid appendages and ecarunculate seeds. It is differing from E. jodhpurensis in having obovate or elliptic-obovate or ovate-elliptic, and abaxially pubescent leaves, 1.5–2.2 mm long peduncle, turbinate involucre, ellipsoid glands, ellipsoid and unequal limb of glands, posterior two limbs are shallowly undulate, deeply keeled, and trigonous capsules. However, another endemic species of Peninsular India, namely, E. erythroclada Boissier (1862: 25) show most congruence with E. telanganensis but differs in having main stem leaves are distinctly or slightly larger than those on branches (vs. main stem and branches of leaves almost equal), leaves pubescent on abaxial (vs. glabrous), involucre 1–1.3 mm long (vs. more than 1.5 mm long), limb of glands unequal, ellipsoid (vs. equal, oblong), posterior two limbs are shallowly undulate (vs. perfectly wavy), capsules deeply keeled and glabrous (vs. shallowly keeled and sparsely hairy). However, two more related species [E. clarkeana Hooker (1887: 253) and E. granulata Forsskål (1775: 94)] were display common key character as leaves of main stems distinctly larger than those on branches, but these species were found to have their own diagnostic features and are clearly distinct from E. telanganensis. Euphorbia clarkeana has prostrate or decumbent habit, stems sparsely hairy, leaves oblong, glabrous, involucre campanulate, limbs of glands minute and as long as glands, capsules obtusely keeled and E. granulata has prostrate habit and covered with densely hispid-villous hairy, leaves ovate-oblong or subobovate, with entire margins, involucre covered with white pilose, ovary hirsute, capsules obtusely keeled and coarsely villous.Published as part of Sadasivaiah, B., Ramakrishna, A., Prasad, K., Devi, N. Sarojini & Rao, Nirmala Babu, 2022, Euphorbia telanganensis (Euphorbiaceae), a new species from Eastern Ghats of Telangana, India, pp. 283-288 in Phytotaxa 572 (3) on pages 284-287, DOI: 10.11646/phytotaxa.572.3.7, http://zenodo.org/record/732225
FIGURE 2 in Rhynchosia ravii (Leguminosae-Papilionoideae), a new species from Andhra Pradesh, India
No full textFIGURE 2. Rhynchosia ravii. (A) habit, (B) stem with glandular hairs, (C) leaf upper surface, (D) leaf lower surface, (E) stipels, (F) bract, (G) racemes, (H) flower, (I) calyx, (J) young fruit, (K) mature fruit, (L) young seeds, (M) mature seeds (Photographer: K. Prasad).Published as part of Prasad, K. & Swamy, A. Narayana, 2014, Rhynchosia ravii (Leguminosae-Papilionoideae), a new species from Andhra Pradesh, India, pp. 155-160 in Phytotaxa 175 (3) on page 158, DOI: 10.11646/phytotaxa.175.3.5, http://zenodo.org/record/514387
Measurement of branching fractions for B → χc1(2)K (K*) at Belle
No full textWe have measured the branching fractions for the exclusive decay modes B→χc1(2)K(K*) using a 140 fb-1 data sample collected by the Belle detector at the KEKB asymmetric-energy e +e- collider. The measured branching fractions for B +→χc1K+, B0→χ c1K0, B0→χc1K* 0 and B+→χc1K*+ decay modes are (4.5±0.2±0.5)×10-4, (3.5±0.3±0.5)×10-4, (3.1±0.3±0.7) ×10-4 and (4.1±0.6±0.9)×10-4, respectively, where the first error is statistical and the second error is systematic. We do not observe statistically significant signals for the B→χc2K(K*) decay modes and set upper limits at the 90% confidence level. We also study the helicity distribution for B→χc1K* decay mode and show that the longitudinal polarization component is dominant. © 2006 Elsevier B.V. All rights reserved.LPH
Search for the suppressed decays B+→K+K+π− and B+→π+π+K−
No full text© 2016 The Author A search is made for the highly-suppressed B meson decays B+→K+K+π− and B+→π+π+K− using a data sample corresponding to an integrated luminosity of 3.0 fb−1 collected by the LHCb experiment in proton–proton collisions at centre-of-mass energies of 7 and 8 TeV. No evidence is found for the decays, and upper limits at 90% confidence level are determined to be B(B+→K+K+π−)<1.1×10−8 and B(B+→π+π+K−)<4.6×10−8
First observation of the decay Bs0→K*0K*0
No full textThe first observation of the decay B0s→K∗0K∗0 is reported using 35 pb−1 of data collected by LHCb in proton–proton collisions at a centre-of-mass energy of 7 TeV. A total of 49.8±7.5 B0s→(K+π−)(K−π+) events are observed within ±50 MeV/c2 of the B0s mass and 746 MeV/c2 < mKπ < 1046 MeV/c2, mostly coming from a resonant B0s→K∗0K∗0 signal. The branching fraction and the CP-averaged K∗0 longitudinal polarization fraction are measured to be B(B0s→K∗0K∗0)=(2.81±0.46(stat.)±0.45(syst.)±0.34(fs/ fd))×10−5 and fL =0.31±0.12(stat.)±0.04(syst.)
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