63,792 research outputs found
Benjamin B. Brock Letter : December 1862 (Camp Casey)
No full textBenjamin is writing from Camp Casey in Arlington, Virginia, just outside of the Washington D.C. He describes the devastation he witnessed in along the road from the First and Second Mannasses. He then retraces his regiment's march eastward once they left Jackson, Michigan
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
On subgraphs of C-2k-free graphs and a problem of Kuhn and Osthus
No full textLet c denote the largest constant such that every C-6-free graph G contains a bipartite and C-4-free subgraph having a fraction c of edges of G. Gyori, Kensell and Tompkins showed that 3/8 0, and any integer k >= 2, there is a C-2k-free graph G' which does not contain a bipartite subgraph of girth greater than 2k with more than a fraction (1 - 1/2(2k-2)) 2/2k - 1 (1 + epsilon) of the edges of G'. There also exists a C-2k-free graph G '' which does not contain a bipartite and C-4-free subgraph with more than a fraction (1 - 1/2(k-1)) 1/k - 1 (1 + epsilon) of the edges of G ''. One of our proofs uses the following statement, which we prove using probabilistic ideas, generalizing a theorem of Erdos. For any epsilon > 0, and any integers a, b, k >= 2, there exists an a-uniform hypergraph H of girth greater than k which does not contain any b-colourable subhypergraph with more than a fraction (1 - 1/b(a-1)) (1+e) of the hyperedges of H. We also prove further generalizations of this theorem. In addition, we give a new and very short proof of a result of Kuhn and Osthus, which states that every bipartite C-2k-free graph G contains a C-4-free subgraph with at least a fraction 1/(k - 1) of the edges of G. We also answer a question of Kuhn and Osthus about C-2k-free graphs obtained by pasting together C-2l's (with k > l >= 3).LCBI
Search for B-c(+) decays to two charm mesons
No full textA search for decays of B-c(+) mesons to two charm mesons is performed for the first time using data corresponding to an integrated luminosity of 3.0 fb(-1), collected by the LHCb experiment in pp collisions at centre-of-mass energies of 7 and 8 TeV. The decays considered are B-c(+)-> D-(s)(()*())(+) (D) over bar (()*()0) and Bc(+)-> D-(s)(()*D-)+(()*())(0), which are normalised to high-yield B+-> D-(s)(+)(D) over bar (0)decays. No evidence for a signal is found and limits are set on twelve B-c(+) decay modes. (C) 2018 The Author(s). Published by Elsevier B.V
Measurement of the ratio of prompt χ c to J / ψ production in pp collisions at √s = 7 TeV
No full textThe 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
Stenus (Nestus) dolosus Casey 1884
No full textStenus (Nestus) dolosus Casey, 1884 Stenus dolosus Casey, 1884: 108. Stenus dolosus – Puthz 1975a: 124. Stenus (Nestus) dolosus – Puthz 1972b: 171. Stenus (s. str.) dolosus – Bernhauer & Schubert 1911: 157. — Campbell & Davies 1991: 111. Stenus jejunus Casey, 1884: 112. Stenus villosus Casey, 1884: 109. Stenus villosus – Casey 1892: 711. Stenus (Nestus) villosus – L. Benick 1938: 266. Stenus (s. str.) villosus – Bernhauer & Schubert 1911: 168. Material examined CANADA: 1 ♀, Yukon Territory, 24 mi w Whitehorse, Alaska Hwy., 2000’, 60°51’N 136°36’W, 21 Jun. 1977, R.E. Morlan, J.V. Matthews, R.E. Roughley leg. (Yukon Refugium Project) (UASM). USA: 1 ♀, ‘ Wisconsin. Kenosha Co.; Chiwaukee Prairie, Carol Beach. 26: IV:1974. Leg: W. Suter.’, ‘FM(HD)#74-65. Ber.: sandy soil at water table. WS#74-30C’ (FMNH); 1 ♀, Ithaca, Cayuga Lake, 17 Aug. 1928, Dr. Rambousek leg., L. Hromadka det., 1979 (AR); 1 ♂, Ottawa Co., Ohio, South Bath Is., Squaw Harbor, Put-in-Bay, washed-up eel-grass on sand beach, 2 Aug. 1979, S.W. Nichols leg. (FMNH); 1 ♂, Michigan, Clinton Co., Rose L. Exp. Sta. ex mud edge, Typha marsh, 3 Sep. 1965, Thomas Hlavac leg. (FMNH); 1 ♂, ‘Volga S.D. Edge of Pond. 5 May 1966. V.M. Kirk’, ‘N.M. Downie Colln. 1992 Acc. Z-18,343 FIELD MUSEUM’ (FMNH); 1 ♂, ‘Rossie, N.Y. C-15 1965. N.M. Downie leg.’, ‘N.M. Downie Colln. 1992 Acc. Z-18,343 FIELD MUSEUM’ (FMNH); 1 ♀, ‘Tompkins Co, N.Y. F-15 1967. N.M. Downie leg.’, ‘N.M. Downie Colln. 1992 Acc. Z-18,343 FIELD MUSEUM’ (FMNH). Remarks Terra typica: USA: ‘Fort Garland, Colorado’; for S. villosus: ‘California’; for S. jejunus: ‘British Columbia’. Casey (1892) himself synonymized S. jejunus with S. villosus. Revising all three holotypes, Puthz (1972a) found them to be conspecific and placed S. villosus in synonymy with S. dolosus. Campbell & Davies (1991) reported this species for Alaska and most provinces of Canada: Yukon Territory, Northwest Territories, Alberta, Saskatchewan, Manitoba, Ontario, Quebec and New Brunswick, without citing material.Published as part of Ryvkin, Alexandr B., 2012, New species and records of Stenus (Nestus) of the canaliculatus group, with the erection of a new species group (Insecta: Coleoptera: Staphylinidae: Steninae), pp. 1-62 in European Journal of Taxonomy 13 on pages 19-20, DOI: 10.5852/ejt.2012.13, http://zenodo.org/record/385777
Measurement of the CKM angle gamma from a combination of B->Dh analyses
No full textA combination of three LHCb measurements of the CKM angle gamma is presented. The decays B->DK and B->Dpi are used, where D denotes an admixture of D0 and D0-bar mesons, decaying into K+K-, pi+pi-, K+-pi-+, K+-pi-+pi+-pi-+, KSpi+pi-, or KSK+K- final states. All measurements use a dataset corresponding to 1.0 fb-1 of integrated luminosity. Combining results from B->DK decays alone a best-fit value of gamma = 72.0 deg is found, and confidence intervals are set gamma in [56.4,86.7] deg at 68% CL, gamma in [42.6,99.6] deg at 95% CL. The best-fit value of gamma found from a combination of results from B->Dpi decays alone, is gamma = 18.9 deg, and the confidence intervals gamma in [7.4,99.2] deg or [167.9,176.4] deg at 68% CL, are set, without constraint at 95% CL. The combination of results from B->DK and B->Dpi decays gives a best-fit value of gamma = 72.6 deg and the confidence intervals gamma in [55.4,82.3] deg at 68% CL, gamma in [40.2,92.7] deg at 95% CL are set. All values are expressed modulo 180 deg, and are obtained taking into account the effect of D0-D0bar mixing
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