| 1. |
- Abelev, Betty, et al.
(författare)
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Long-range angular correlations on the near and away side in p-Pb collisions at root S-NN=5.02 TeV
- 2013
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Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 719:1-3, s. 29-41
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Tidskriftsartikel (refereegranskat)abstract
- Angular correlations between charged trigger and associated particles are measured by the ALICE detector in p-Pb collisions at a nucleon-nucleon centre-of-mass energy of 5.02 TeV for transverse momentum ranges within 0.5 < P-T,P-assoc < P-T,P-trig < 4 GeV/c. The correlations are measured over two units of pseudorapidity and full azimuthal angle in different intervals of event multiplicity, and expressed as associated yield per trigger particle. Two long-range ridge-like structures, one on the near side and one on the away side, are observed when the per-trigger yield obtained in low-multiplicity events is subtracted from the one in high-multiplicity events. The excess on the near-side is qualitatively similar to that recently reported by the CMS Collaboration, while the excess on the away-side is reported for the first time. The two-ridge structure projected onto azimuthal angle is quantified with the second and third Fourier coefficients as well as by near-side and away-side yields and widths. The yields on the near side and on the away side are equal within the uncertainties for all studied event multiplicity and p(T) bins, and the widths show no significant evolution with event multiplicity or p(T). These findings suggest that the near-side ridge is accompanied by an essentially identical away-side ridge. (c) 2013 CERN. Published by Elsevier B.V. All rights reserved.
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| 2. |
- Abelev, Betty, et al.
(författare)
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Measurement of prompt J/psi and beauty hadron production cross sections at mid-rapidity in pp collisions at root s=7 TeV
- 2012
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; :11
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Tidskriftsartikel (refereegranskat)abstract
- The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at root s = 7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L-int = 5.6 nb(-1). The fraction of J/psi from the decay of long-lived beauty hadrons was determined for J/psi candidates with transverse momentum p(t) > 1,3 GeV/c and rapidity vertical bar y vertical bar < 0.9. The cross section for prompt J/psi mesons, i.e. directly produced J/psi and prompt decays of heavier charmonium states such as the psi(2S) and chi(c) resonances, is sigma(prompt J/psi) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 8.3 +/- 0.8(stat.) +/- 1.1 (syst.)(-1.4)(+1.5) (syst. pol.) mu b. The cross section for the production of b-hadrons decaying to J/psi with p(t) > 1.3 GeV/c and vertical bar y vertical bar < 0.9 is a sigma(J/psi <- hB) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 1.46 +/- 0.38 (stat.)(-0.32)(+0.26) (syst.) mu b. The results are compared to QCD model predictions. The shape of the p(t) and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the b (b) over bar pair total cross section and d sigma/dy at mid-rapidity.
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| 3. |
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| 4. |
- Abouhatab, Assem, et al.
(författare)
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Opportunities and Constraints for Small Agricultural Exporters in Egypt
- 2013
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Ingår i: International Food and Agribusiness Management Review. - 1096-7508 .- 1559-2448. ; 16, s. 77-100
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Tidskriftsartikel (refereegranskat)abstract
- This study analyzed specialist small-and medium-sized agricultural export firms in Egypt in order to identify perceived opportunities and barriers regarding present and future export activities. The results indicate that these firms have to deal with stiff foreign competition in terms of price and quality criteria, while lacking relevant knowledge and information on how to deal with these challenges. The firms that perceived most future opportunities from exports were identified as using e. g. digital information sources and were able to source products from export-committed domestic farmers.
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| 5. |
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| 6. |
- de Jong, Roelof S., et al.
(författare)
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4MOST-4-metre Multi-Object Spectroscopic Telescope
- 2014
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Ingår i: Ground-based and Airborne Instrumentation for Astronomy V. - : SPIE. - 0277-786X .- 1996-756X. ; 9147
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Konferensbidrag (refereegranskat)abstract
- 4MOST is a wide-field, high-multiplex spectroscopic survey facility under development for the VISTA telescope of the European Southern Observatory (ESO). Its main science drivers are in the fields of galactic archeology, high-energy physics, galaxy evolution and cosmology. 4MOST will in particular provide the spectroscopic complements to the large area surveys coming from space missions like Gaia, eROSITA, Euclid, and PLATO and from ground-based facilities like VISTA, VST, DES, LSST and SKA. The 4MOST baseline concept features a 2.5 degree diameter field-of-view with similar to 2400 fibres in the focal surface that are configured by a fibre positioner based on the tilting spine principle. The fibres feed two types of spectrographs; similar to 1600 fibres go to two spectrographs with resolution R> 5000 (lambda similar to 390-930 nm) and similar to 800 fibres to a spectrograph with R> 18,000 (lambda similar to 392-437 nm & 515-572 nm & 605-675 nm). Both types of spectrographs are fixed-configuration, three-channel spectrographs. 4MOST will have an unique operations concept in which 5 year public surveys from both the consortium and the ESO community will be combined and observed in parallel during each exposure, resulting in more than 25 million spectra of targets spread over a large fraction of the southern sky. The 4MOST Facility Simulator (4FS) was developed to demonstrate the feasibility of this observing concept. 4MOST has been accepted for implementation by ESO with operations expected to start by the end of 2020. This paper provides a top-level overview of the 4MOST facility, while other papers in these proceedings provide more detailed descriptions of the instrument concept[1], the instrument requirements development[2], the systems engineering implementation[3], the instrument model[4], the fibre positioner concepts[5], the fibre feed[6], and the spectrographs[7].
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| 7. |
- Di Corato, Luca, et al.
(författare)
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Farmland Investments in Africa: What’s the Deal?
- 2014
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Large-scale foreign investments in African farmland are rising and may contribute to agricultural productivity growth and economic development. However, host countries sometimes have to wait longer for the economic benefits to arrive than initially expected. In this respect, the timing of project development is crucial and depends on the economic incentives provided to the investors. We therefore present a dynamic stochastic programming model that reflects the typical bargaining situation concerning large land deals in Africa and allows the effect of market- and country-specific risks and taxation to be assessed. The model shows that commodity price volatility increases the value of the land development option, but slows down the land development process. Furthermore, it shows that host country attempts to negotiate fixed commitments to the speed of project development may run counter to the structure of economic incentives at the project site. The applicability of the model is demonstrated for a recent 10,000-hectare cotton project in Ethiopia. Response surface estimations suggest that Ethiopia has negotiated a contract under which it will receive about half the expected total project value, as long as it levies the regular corporate tax rate.
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| 8. |
- Di Corato, Luca, et al.
(författare)
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Farmland Investments in Africa : What’s the Deal?
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Large-scale foreign investments in African farmland are rising and may contribute to agricultural productivity growth and economic development. However, host coun- tries sometimes have to wait longer for the economic benefits to arrive than initially expected. In this respect, the timing of project development is crucial and depends on the economic incentives provided to the investors. We therefore present a dynamic stochastic programming model that reflects the typical bargaining situation concerning large land deals in Africa and allows the effect of market- and country-specific risks and taxation to be assessed. The model shows that commodity price volatility increases the value of the land development option, but slows down the land development process. Furthermore, it shows that host country attempts to negotiate fixed commitments to the speed of project development may run counter to the structure of economic incentives at the project site. The applicability of the model is demonstrated for a recent 10,000-hectare cotton project in Ethiopia. Response surface estimations suggest that Ethiopia has negotiated a contract under which it will receive about half the expected total project value, as long as it levies the regular corporate tax rate.
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| 9. |
- Galata, Lena, et al.
(författare)
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Cross-Atlantic Differences in Biotechnology and GMOs: A Media Content Analysis
- 2014
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Ingår i: Agricultural Cooperative Management and Policy : New Robust, Reliable and Coherent Modelling Tools. - Cham : Springer International Publishing. - 9783319066349 ; , s. 299-314
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Bokkapitel (refereegranskat)abstract
- Different regulations about the permission and approval rate of biotechnology and genetically modified organisms (GMOs) between the USA and Europe have been controversial for decades. While there is a wide scientific coverage of what may be the cause of this divergence, little is known about the role that popular media play in the related political discourse. We analyzed the media coverage of biotechnology topics in both the USA and UK from 2011-2013 by examining two opinion-leading newspapers. We test the hypothesis that the respective media content reflects differences in transatlantic policies towards biotechnology. The two newspapers differed in reporting intensity but were alike in their content about GMOs: with the central actors being scientists and NGOs, arguing mostly in the field of the agricultural sector, the debate seems to be locked in a stalemate of potential risks re-iterated against potential benefits, with none of the two positions clearly dominating the discourse.
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| 10. |
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