44,008 research outputs found
Neutron emission spectroscopy of D plasmas at JET with a compact liquid scintillating neutron spectrometer
No full textNeutron emission spectroscopy is a diagnostic technique that allows for energy measurements of neutrons born in nuclear reactions. The JET tokamak fusion experiment (Culham, UK) has a special role in this respect as advanced spectrometers for 2.5 MeV and 14 MeV neutrons have been developed here for the first time for measurements of the neutron emission spectrum from D and DT plasmas with unprecedented accuracy. Twin liquid scintillating neutron spectrometers were built and calibrated at the Physikalisch-Technische Bundesanstalt (PTB) (Braunschweig, Germany) and installed on JET in the recent years with tangential-equatorial (KM12) and vertical-radial (KM13) view lines, with the latter only recently operational. This article reports on the performance of KM12 and on the development of the data analysis methods in order to extract physics information upon D ions kinematics in JET auxiliary-heated D plasmas from 2.5 MeV neutron measurements. The comparison of these results with the correspondents from other JET neutron spectrometers is also presented: their agreement allows for JET unique capability of multi-lines of sight neutron spectroscopy and for benchmarking other 14 MeV neutron spectrometers installed on the same lines of sight in preparation for the DT experimental campaign at JET
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
No full textFirst 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)
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 B0–B0 oscillation frequency Δmd with the decays B0→D−π+ and B0→ J/ψK∗0
No full textThe B
0
–B
0
oscillation frequency Δmd is measured by the LHCb experiment using a dataset corresponding
to an integrated luminosity of 1.0 fb−1
of proton–proton collisions at √
s = 7 TeV, and is found to be
Δmd
=0.5156±0.0051 (stat.)±0.0033 (syst.) ps−1
. The measurement is based on results from analyses
of the decays B
0
→ D
−π
+ (D
−
→ K
+π
−π
−) and B
0
→ J/ψK
∗0
(J/ψ →μ
+μ
−,K
∗0
→ K
+π
−) and
their charge conjugated modes
Parasterope gamurru Syme & Poore, 2006, new species
No full text<i>Parasterope gamurru</i> new species <p>Figures 1, 2</p> <p>Material examined.— Holotype: NMV J53224 one adult female on slide; Paratype: NMV J53225 one adult male on slide.</p> <p>Type Locality.—Patch Reef, Lizard Island, Queensland, Australia. 14°41.038' S, 145°27.003' E, 3 m. Collected by T. Oakley, using hand net while snorkeling. Collection date: 3 February, 2000.</p> <p>Distribution.—Known only from type locality.</p> <p>Diagnosis.—First antenna of adult female with 4 dorsal nodes on article 5.</p> <p>Description.—Adult female. NMV J53224. Carapace oval, broadening at posterior, inner end of incisur at valve midheight, carapace length 1.36 mm, height 0.89 mm. Rostrum with 20 setae anterior and dorsal to list, anteroventral infold with 30 setae between list and valve edge, list continuing ventrally to posterior where it has broad triangular setae with smaller setae placed between, and pores between list and valve margin; number of setae unable to be determined due to fragmentation of carapace. Selvage: fringe of hairs at inner end of ventral margin of incisur. Vestment: anterodorsal corner of vestment proximal to infold with clusters of spines.</p> <p>First antenna: article 2 with 1 spinous dorsal seta and 1 lateral seta, small dorsodistal lateral spines. Article 3 with 1 short ventral seta and 6 dorsal setae (only 4 on left first antenna but this presumed aberrant). Article 4 with 1 dorsal seta and 2 ventral setae. Article 5 dorsal margin with 4 nodes; sensory seta with 0 short proximal and 6 terminal filaments. Article 6 with medial seta, 1.5x length of a­claw. Article 7 with a­claw, b­seta with 4 marginal filaments, c­seta with 4 marginal filaments. Article 8 with no d­seta, e­seta bare with blunt tip, f­seta bent dorsally with 3 marginal filaments, g­seta with 6 marginal filaments.</p> <p>Second antenna: protopod with small distal medial seta. Endopod with only 1 suture visible, end article with terminal filament. Exopod: article 2 seta with short marginal spines, reaching article 9. Articles 4–9 with basal spines and long setae with long marginal spines. Article 9 also with 1 further long seta with long marginal spines, and 2 shorter setae.</p> <p>Mandible: coxale endite with small seta at base of ventral branch, ventral branch with spines (longer at base), ventral margin of dorsal branch undulating, with rows of small serrations. Basale endite with 4 spinous end setae, 3 triaenid setae with 4 paired spines excluding terminal pair, 1 dwarf seta, and glandular peg. Basale dorsal margin with 2 long terminal setae, equilength. Exopod with hirsute tip and 2 subterminal setae, exopod length approximately 0.6 of dorsal margin of first endopod article. Endopod article 1 with 3 long ventral setae (1 with short spines, 2 with long spines). Endopod article 2: ventral margin with 3 long terminal setae with short spines, dorsal margin with stout a­, b­, c­, and dsetae, 0–1 slender seta proximal to a­seta (0 on left mandible, 1 on right mandible); medial side with 6 cleaning setae, and 1 g­seta at base of d­seta; lateral side with 1 long e­seta between b­ and c­ setae, and 1 long f­seta between c­ and d­ setae. Endopod article 3 with stout dorsal claw, 3 stout setae and 2 slender setae.</p> <p>Maxilla (fourth limb): triangular epipod. Endites folded and obscured. Basale with 1 dorsal medial proximal seta, 1 dorsal medial distal seta, 1 ventral medial proximal seta, 1 long ventral lateral distal seta with spines. Endopod article 1 with short alpha seta and long beta seta. Endopod article 2 with long terminal seta.</p> <p>Fifth limb: comb with long exopod seta. Comb folded; details of other setae uncertain. Sixth limb: anterior margin with seta at each endite suture, lateral flap of skirt with 2 setae, posteroventral margin with 13 setae with spines. Seventh limb: with 12 setae, each with 3– 4 bells. Combs forming obtuse angle.</p> <p>Furca: each lamella with 8 claws and setae decreasing evenly in size, and 1 lateral seta pointing posteriorly. Posterior of body: fragmented, but appears rounded and hirsute. No obvious thumb­like process. Reproductive organs: presence/absence unable to be determined. Bellonci organ and medial eye: presence/absence unable to be determined. Lateral eye: with 12 visible ommatidia, darkly pigmented. Lips: upper and lower lips hirsute lobes, upper lip with lateral spine. Gills: well developed, number of pairs unable to be determined.</p> <p>Adult male. NMV J53225. All features compared to adult female; important differences noted here: carapace length 1.18 mm, height at middle 0.68 mm. Posterior row of hairs present. First antenna: sensory seta with robust stem and many filaments. Articles 7– 8 with very long c­ and f­ setae (twice length of first antenna) each with approximately 30 marginal filaments. Second antenna: endopod with 3 articles. Article 2 with 2 lateral setae, article 3 recurved with 1 proximal seta. Mandible basale dorsal margin with 1 seta at midlength. Lateral eye with 20 ommatidia. Reproductive organs: presence/absence unable to be determined.</p> <p> Remarks.—The presence of nodes on the dorsal margin of article 5 of the first antenna is unusual for females in this family (males often have a “bumpy” dorsal margin on articles 5 and 6). <i>Parasterope gamurru</i> can be distinguished from all other species in the genus by this feature. The only other species in the family with nodes (on females) are <i>Amboleberis americana</i> (Mller, 1890) (with 4–6), <i>Amboleberis cubensis</i> Lalana & Kornicker, 1997 (with 7–8), and <i>Dolasterope johanseni</i> Poulsen, 1965 and species of <i>Tetraleberis</i> Kornicker, 1981 (all with 1 node).</p> <p>The male described here is similar to males of several other known species in the genus but is assumed to be conspecific with the female, as it was found in the same sample and is morphologically similar. It differs from the female in the presence of 1 seta at midlength on the dorsal margin of the mandible basale; sexual dimorphism of this character is known in many species.</p> <p> Species of <i>Parasterope</i> are known from most oceans and depths (excluding the Arctic). Although species have been described from the Indo –Pacific (Kornicker, 1970; Poulsen, 1965) and the southeastern coastline of Australia (Kornicker & Poore, 1996), none have been described from Queensland. <i>P. gamurru</i> extends the Australian distribution of this genus.</p> <p>Etymology.—“ Gamurru ” is an Australian aboriginal word from the Yolnu language of northern Australia, meaning “nose” or “point,” in reference to the nodes on the first antenna for this species.</p>Published as part of <i>Syme, Anna E. & Poore, Gary C. B., 2006, Three new ostracod species from coastal Australian waters (Crustacea: Ostracoda: Myodocopa: Cylindroleberididae), pp. 51-67 in Zootaxa 1305</i> on pages 52-54, DOI: <a href="http://zenodo.org/record/173718">10.5281/zenodo.173718</a>
FIGURE 4 in Three new ostracod species from coastal Australian waters (Crustacea: Ostracoda: Myodocopa: Cylindroleberididae)
No full textFIGURE 4. Diasterope wirraka, new species, adult male paratype NMV J53211, A, carapace; B, first antenna, right, m.v., filaments on sseta not shown, base of medial seta on sixth article shown as circle, dseta tiny peg (not shown), cseta missing, base shown as circle (108X); C, endopod of second antenna, right, m.v. (113X); D, posterior of body from left side showing copulatory organ and first claw of furca (48X).Published as part of Syme, Anna E. & Poore, Gary C. B., 2006, Three new ostracod species from coastal Australian waters (Crustacea: Ostracoda: Myodocopa: Cylindroleberididae), pp. 51-67 in Zootaxa 1305 on page 60, DOI: 10.5281/zenodo.17371
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
Measurement of CP observables in B-+/- -> D(*)K-+/- and B-+/- -> D(*)pi(+/-) decays
No full textMeasurements of CP observables in B-+/- -> D(*)K-+/- and B-+/- -> D(*)pi(+/-) decays are presented, where D(*) indicates a neutral Dor D* meson that is an admixture of D(*)(0) and (D) over bar(*)(0) states. Decays of the D* meson to the D pi(0)and D gamma final states are partially reconstructed without inclusion of the neutral pion or photon, resulting in distinctive shapes in the Bcandidate invariant mass distribution. Decays of the D meson are fully reconstructed in the K-+/-pi(-/+), K+K- and pi(+)pi(-) final states. The analysis uses a sample of charged Bmesons produced in ppcollisions collected by the LHCb experiment, corresponding to an integrated luminosity of 2.0, 1.0 and 2.0fb- 1taken at centre- of- mass energies of root s = 7, 8 and 13 TeV, respectively. The study of B-perpendicular to -> D*K-perpendicular to and B-perpendicular to -> D*pi(perpendicular to) decays using a partial reconstruction method is the first of its kind, while the measurement of B-+/- -> DK +/- and B-+/- -> D pi(+/-) decays is an update of previous LHCb measurements. The B-+/- -> DK +/- results are the most precise to date. (c) 2017 The Author. Published by Elsevier B. V
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
Diasterope wirraka Syme & Poore, 2006, new species
No full textDiasterope wirraka new species Figures 3, 4 Material examined.— Holotype: NMV J 53210 one adult female on slide and in alcohol. Paratypes: NMV J 53211 one adult male on slide and in alcohol; NMV J 53212 one adult female on slide and in alcohol, NMV J 53213 one adult female on slides and in alcohol. Type Locality.—Eastern Bass Strait, Victoria, Australia. 15.3 km ESE of eastern edge of Lake Tyers. 37 ° 53.23 ' S, 148 ° 15.24 ' E, benthic, 43 m. Collected by N. Coleman using SmithMcIntyre grab. Collection date: 1 February 1991. Distribution.—Known only from type locality. Diagnosis.—Article 3 of first antenna with 5 dorsal setae; mandible basale with 3 (male) or 5 (female) dorsal setae; seventh limb with 12 setae. Description.—Adult female. NMV J 53210. Carapace oval and slightly broader posteriorly, inner end of incisur at valve midheight, posterior end evenly rounded, carapace length 1.64 mm, height 0.84 mm. Infold: rostrum with 60 setae anterior and dorsal to list, anteroventral infold with 20 setae between list and valve edge, narrow list continuing ventrally with about 40 setae on list, list broadening slightly at posterior infold with 21 broad triangular transparent setae and 23 smaller setae placed between. Selvage: fringe of hairs at inner end of ventral margin of incisur. Vestment: anterodorsal corner of vestment proximal to infold with clusters of long spines. First antenna: article 2 with 1 spinous dorsal seta and 1 lateral seta. Article 3 with 1 short ventral seta and 5 dorsal setae; first 2 with longer spines and remainder with short marginal spines. Article 4 with 1 dorsal seta with short marginal spines and 2–3 ventral setae. Article 5 with sensory seta with 1 short proximal and 6 terminal filaments. Article 6 with bare medial seta, 1.5 x length of aclaw. Article 7 with aclaw, bseta with 4 marginal filaments, cseta with 4 marginal filaments. Article 8 with minute peg dseta, eseta bare with blunt tip, fseta bent dorsally with bifurcate tip, gseta with 4 marginal filaments. Second antenna: protopod with bare distal medial seta. Endopod with 3 articles, end article with terminal filament. Exopod: article 2 seta with marginal spines, reaching ninth article. Articles 3–7 with long setae with marginal spines. Article 8 with basal spine and long seta with marginal spines. Article 9 with larger basal spine, 1 shorter seta and 2 long setae with marginal spines. Mandible: coxale endite missing. Basale endite with 4 spinous end setae, 3 triaenid setae with 5–6 paired spines excluding terminal pair, 2 dwarf setae of equal length and small glandular peg. Basale: ventral margin with 1 smaller triaenid seta with 2 pairs of spines excluding terminal pair, proximal to Ushaped boss; dorsal margin with 5 setae at midlength and 2 long terminal setae, equilength, with spines. No hairs/spines on medial side of basale. Exopod with hirsute tip and 2 subterminal setae, exopod length approximately 0.4 of dorsal margin of first endopod article. Endopod article 1 with 3 long ventral setae (1 with short spines, 2 with long spines). Endopod article 2: ventral margin with 3 long terminal setae with short spines, dorsal margin with stout a, b, c, and dsetae, 2 slender seta proximal to aseta; medial side with 9 cleaning setae, and 1 long gseta distal to base of dseta; lateral side with 1 long eseta between b and c setae and 1 long fseta between c and d setae. Endopod article 3 with stout dorsal claw, 4 stout spinous setae and 1 slender shorter spinous seta. Maxilla (fourth limb): epipod missing, endites folded and obscured. Basale spinous on medial side with 1 proximal seta at midheight. Ventral margin with 5 setae near midlength and 1 long spinous terminal seta. Dorsal margin with 2 proximal setae, 2 middle setae and 1 distal seta. Endopod article 1 with ventral spines, short alpha seta and long beta seta. Endopod article 2 with long terminal seta. Fifth limb: missing on holotype. For paratype NMV J 53212, comb with long exopod seta, 4 shorter lateral setae near ventral margin of comb. Sixth limb: anterior margin with seta at each endite suture, lateral flap of skirt with 4 setae, ventral margin with 14 setae with spines, posteroventral corner with 6 plumose setae. Seventh limb: with 12 setae, each with 3 bells. Combs forming obtuse angle, each comb with 8 teeth. Furca: each lamella with 7 claws and setae decreasing evenly in size, and 1 lateral seta pointing posteriorly. Bellonci organ with no obvious sutures. Medial eye with 3 pigmented sections. Lateral eye with 14 ommatidia. Lips: presence/absence unable to be determined. Posterior of body: thumblike dorsal process with long spines at tip and shorter spines at midheight. Reproductive organs: presence/absence unable to be determined. Gills: partly obscured and distorted by embryos in marsupium, but appear welldeveloped. Embryos: holotype with 6 embryos in marsupium; length of typical embryo 0.33 mm. Adult male. NMV J 53211. All features compared to adult female; important differences noted here: carapace length 1.50 mm, height 0.76 mm. First antenna: article 5 with sensory seta with robust stem and many filaments. Article 7 with cseta broken from both antennae. Article 8 with fseta with 8 marginal filaments and gseta with 7 marginal filaments. Fseta not particularly long, approximately equal to length of first antenna. Second antenna: endopod with 3 articles. Article 2 with 4 setae, article 3 narrower than other articles, recurved, with 1 proximal seta. Mandible: basale dorsal margin with 3 setae at midlength, endopod article 2 with 3 dorsal proximal setae. Lateral eye: with 18 ommatidia. Reproductive organs: small oval with vas deferens leading to copulatory structure. Posterior of body: rounded posterior process. Remarks.— The existing diagnosis of Diasterope includes a mandible exopod length greater than 50 percent of length of dorsal margin of endopod article 1. Diasterope wirraka has a relative exopod length of only 40 %. However, the species fits more closely into Diasterope than into other genera and is thus included in this genus here. As noted above, a phylogenetic analysis is in progress and may alter the available genera of the Cylindroleberididae; thus, a formal change to the diagnostic features of Diasterope is not presented here. Diasterope wirraka is similar to D. grisea (Brady, 1898) (New Zealand) but differs in the following characters: carapace smaller (adult female 1.64 mm compared to 2.64 mm), article 3 of first antenna with 5 (not 6) dorsal setae; mandible basale of female with 5 (not 3) dorsal setae, male fseta of first antenna of similar length to gseta (not twice as long), and male carapace with no posterior row of hairs. D. wirraka is also similar to D. schmitti Kornicker, 1975 (Antarctica) in the number of dorsal setae on the mandible basale (5) but differs in the following characters: carapace much smaller (adult female 1.64 mm compared to 3.51 mm), article 3 of first antenna with 5 (not 6–7) dorsal setae, seventh limb with 12 (not 31) setae. No males are known for D. schmitti. D. wirraka c an be differentiated from D. procax Kornicker & Iliffe, 2000 (Bahamas), D. pilosa Poulsen, 1965 (Northeast Pacific) and D. bisetosa Poulsen, 1965 (Red Sea) by the number of dorsal setae on the mandible basale (5 compared to 1). Comparisons have not been made with those species for which only juvenile males are known, D. canina Poulsen, 1965 and D. tenuiseta Poulsen, 1965, both from the West Indies. The adult male carapace is lacking a posterior row of hairs. Presence of this row of hairs is common in males of the subfamily. The relatively short fseta is in contrast to most known males of the subfamily, which have very long c and fsetae (twice length of first antenna). Species of Diasterope have a disjunct distribution, known from the Red Sea, northwest Atlantic, northeast Pacific and New Zealand to Antarctica. D. wirraka has morphological similarities with species from New Zealand and Antarctica, and its discovery extends the distribution of this genus to southeast Australia. Etymology.—“ Wirraka ” is an Australian aboriginal word from the Wemba Wemba language of southeastern Australia, meaning “to swim.”Published as part of Syme, Anna E. & Poore, Gary C. B., 2006, Three new ostracod species from coastal Australian waters (Crustacea: Ostracoda: Myodocopa: Cylindroleberididae), pp. 51-67 in Zootaxa 1305 on pages 56-60, DOI: 10.5281/zenodo.17371
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