592 research outputs found
The environmental context of the Neolithic monuments on the Brodgar Isthmus, Mainland, Orkney
This work was funded in part by Historic Environment Scotland.The World Heritage Sites of Orkney, Scotland contain iconic examples of Neolithic monumentality that have provided significant information about this period of British prehistory. However, currently, a complete understanding of the sites remains to be achieved. This is, in part, because the monuments lack an adequate context within the broader palaeolandscape. Recent investigations (seismic geophysical survey, microfossil analysis and 14C dating) in and around the Brodgar Isthmus, both onshore and offshore, are used to reconstruct the landscapes at a time when sea-level, climate and vegetation were different to that experienced today. Results show that in the early Neolithic the isthmus between the Ring of Brodgar and Stones of Stenness was broader with a smaller loch to the west. Furthermore this landscape contained sandstone outcrops that would have provided a potential source of stone for monument construction. Microfossil analysis and radiocarbon dates demonstrate that the Loch of Stenness was transformed from freshwater to brackish during the early Neolithic, perhaps immediately preceding construction of the major monuments. Finally, the analysis of our data suggests that sediment influx to the loch shows a tenfold increase coincident with widespread vegetation change that straddles the Mesolithic/Neolithic transition at c. 8 ka cal. B.P. These results provide, for the first time, a landscape context for the Neolithic sites on the isthmus.PostprintPeer reviewe
A Survey of the Harvesting Histories of Some Poorly Regenerated Aspen Stands in Northern Minnesota
Off-axis symbiosis found: characterization and biogeography of bacterial symbionts of Bathymodiolus mussels from Lost City hydrothermal vents
Transitional experiences of post-16 sports education: Jack's story
This paper explores the layered transitional experiences of a semi-professional athlete named Jack (a pseudonym) between the fields of professional sport and further and higher education. Our analysis is framed by the quadripartite framework of structuration and focuses on Jack's 'in-situ' practices at his college and university in order to illustrate how these can operate to reproduce, transform, and challenge the habitual discourses and rituals that circulate within these institutions by generating forms of corporeal empowerment for young athletes who have valued conjunctural knowledge. The findings highlight the fragility of the transition process and raise questions regarding how the experiences of young people are shaped by the relationships between employment and post-16 education. Jack's experiences have implications for both policy and practice within further education and higher education. © 2012 © 2012 Taylor & Francis
A massive, Late Neolithic pit structure associated with Durrington Walls Henge
YesA series of massive geophysical anomalies, located south of the Durrington Walls henge monument, were identified during fluxgate gradiometer survey undertaken by the Stonehenge Hidden Landscapes Project (SHLP). Initially interpreted as dewponds, these data have been re-evaluated, along with information on similar features revealed by archaeological contractors undertaking survey and excavation to the north of the Durrington Walls henge. Analysis of the available data identified a total of 20 comparable features, which align within a series of arcs adjacent to Durrington Walls. Further geophysical survey, supported by mechanical coring, was undertaken on several geophysical anomalies to assess their nature, and to provide dating and environmental evidence. The results of fieldwork demonstrate that some of these features, at least, were massive, circular pits with a surface diameter of 20m or more and a depth of at least 5m. Struck flint and bone were recovered from primary silts and radiocarbon dating indicates a Late Neolithic date for the lower silts of one pit. The degree of similarity across the 20 features identified suggests that they could have formed part of a circuit of large pits around Durrington Walls, and this may also have incorporated the recently discovered Larkhill causewayed enclosure. The diameter of the circuit of pits exceeds 2km and there is some evidence that an intermittent, inner post alignment may have existed within the circuit of pits. One pit may provide evidence for a recut; suggesting that some of these features could have been maintained through to the Middle Bronze Age. Together, these features represent a unique group of features related to the henge at Durrington Walls, executed at a scale not previously recorded.The University of Bradford Research Development Fund and the University of St Andrews funded this open access publication.Supplementary data can be found at https://intarch.ac.uk/journal/issue55/4/supp-text.htm
Measurement of the branching fraction
The branching fraction is measured in a data sample
corresponding to 0.41 of integrated luminosity collected with the LHCb
detector at the LHC. This channel is sensitive to the penguin contributions
affecting the sin2 measurement from The
time-integrated branching fraction is measured to be . This is the most precise measurement to
date
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.Comment: 15 pages, 10 figures; minor revisions on May 23, 201
Absolute luminosity measurements with the LHCb detector at the LHC
Absolute luminosity measurements are of general interest for colliding-beam
experiments at storage rings. These measurements are necessary to determine the
absolute cross-sections of reaction processes and are valuable to quantify the
performance of the accelerator. Using data taken in 2010, LHCb has applied two
methods to determine the absolute scale of its luminosity measurements for
proton-proton collisions at the LHC with a centre-of-mass energy of 7 TeV. In
addition to the classic "van der Meer scan" method a novel technique has been
developed which makes use of direct imaging of the individual beams using
beam-gas and beam-beam interactions. This beam imaging method is made possible
by the high resolution of the LHCb vertex detector and the close proximity of
the detector to the beams, and allows beam parameters such as positions, angles
and widths to be determined. The results of the two methods have comparable
precision and are in good agreement. Combining the two methods, an overall
precision of 3.5% in the absolute luminosity determination is reached. The
techniques used to transport the absolute luminosity calibration to the full
2010 data-taking period are presented.Comment: 48 pages, 19 figures. Results unchanged, improved clarity of Table 6,
9 and 10 and corresponding explanation in the tex
Measurement of the ratio of branching fractions BR(B0 -> K*0 gamma)/BR(Bs0 -> phi gamma) and the direct CP asymmetry in B0 -> K*0 gamma
The ratio of branching fractions of the radiative B decays B0 -> K*0 gamma
and Bs0 phi gamma 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 sqrt(s)=7 TeV. The value obtained is BR(B0 -> K*0 gamma)/BR(Bs0 ->
phi gamma) = 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 BR(B0 -> K*0 gamma), the
branching fraction BR(Bs0 -> phi gamma) is measured to be (3.5 +/- 0.4) x
10^{-5}.
The direct CP asymmetry in B0 -> K*0 gamma decays has also been measured with
the same data and found to be A(CP)(B0 -> K*0 gamma) = (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.Comment: 21 pages, 3 figues, 4 table
Absolute luminosity measurements with the LHCb detector at the LHC
Absolute luminosity measurements are of general interest for colliding-beam
experiments at storage rings. These measurements are necessary to determine the
absolute cross-sections of reaction processes and are valuable to quantify the
performance of the accelerator. Using data taken in 2010, LHCb has applied two
methods to determine the absolute scale of its luminosity measurements for
proton-proton collisions at the LHC with a centre-of-mass energy of 7 TeV. In
addition to the classic "van der Meer scan" method a novel technique has been
developed which makes use of direct imaging of the individual beams using
beam-gas and beam-beam interactions. This beam imaging method is made possible
by the high resolution of the LHCb vertex detector and the close proximity of
the detector to the beams, and allows beam parameters such as positions, angles
and widths to be determined. The results of the two methods have comparable
precision and are in good agreement. Combining the two methods, an overall
precision of 3.5% in the absolute luminosity determination is reached. The
techniques used to transport the absolute luminosity calibration to the full
2010 data-taking period are presented.Comment: 48 pages, 19 figures. Results unchanged, improved clarity of Table 6,
9 and 10 and corresponding explanation in the tex
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