17 research outputs found

    The Athena X-ray Integral Field Unit: a consolidated design for the system requirement review of the preliminary definition phase

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    The Athena X-ray Integral Unit (X-IFU) is the high resolution X-ray spectrometer, studied since 2015 for flying in the mid-30s on the Athena space X-ray Observatory, a versatile observatory designed to address the Hot and Energetic Universe science theme, selected in November 2013 by the Survey Science Committee. Based on a large format array of Transition Edge Sensors (TES), it aims to provide spatially resolved X-ray spectroscopy, with a spectral resolution of 2.5 eV (up to 7 keV) over an hexagonal field of view of 5 arc minutes (equivalent diameter). The X-IFU entered its System Requirement Review (SRR) in June 2022, at about the same time when ESA called for an overall X-IFU redesign (including the X-IFU cryostat and the cooling chain), due to an unanticipated cost overrun of Athena. In this paper, after illustrating the breakthrough capabilities of the X-IFU, we describe the instrument as presented at its SRR, browsing through all the subsystems and associated requirements. We then show the instrument budgets, with a particular emphasis on the anticipated budgets of some of its key performance parameters. Finally we briefly discuss on the ongoing key technology demonstration activities, the calibration and the activities foreseen in the X-IFU Instrument Science Center, and touch on communication and outreach activities, the consortium organisation, and finally on the life cycle assessment of X-IFU aiming at minimising the environmental footprint, associated with the development of the instrument. Thanks to the studies conducted so far on X-IFU, it is expected that along the design-to-cost exercise requested by ESA, the X-IFU will maintain flagship capabilities in spatially resolved high resolution X-ray spectroscopy, enabling most of the original X-IFU related scientific objectives of the Athena mission to be retained. (abridged).Comment: 48 pages, 29 figures, Accepted for publication in Experimental Astronomy with minor editin

    The Athena X-ray Integral Field Unit: a consolidated design for the system requirement review of the preliminary definition phase

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    The Athena X-ray Integral Unit (X-IFU) is the high resolution X-ray spectrometer studied since 2015 for flying in the mid-30s on the Athena space X-ray Observatory. Athena is a versatile observatory designed to address the Hot and Energetic Universe science theme, as selected in November 2013 by the Survey Science Committee. Based on a large format array of Transition Edge Sensors (TES), X-IFU aims to provide spatially resolved X-ray spectroscopy, with a spectral resolution of 2.5 eV (up to 7 keV) over a hexagonal field of view of 5 arc minutes (equivalent diameter). The X-IFU entered its System Requirement Review (SRR) in June 2022, at about the same time when ESA called for an overall X-IFU redesign (including the X-IFU cryostat and the cooling chain), due to an unanticipated cost overrun of Athena. In this paper, after illustrating the breakthrough capabilities of the X-IFU, we describe the instrument as presented at its SRR (i.e. in the course of its preliminary definition phase, so-called B1), browsing through all the subsystems and associated requirements. We then show the instrument budgets, with a particular emphasis on the anticipated budgets of some of its key performance parameters, such as the instrument efficiency, spectral resolution, energy scale knowledge, count rate capability, non X-ray background and target of opportunity efficiency. Finally, we briefly discuss the ongoing key technology demonstration activities, the calibration and the activities foreseen in the X-IFU Instrument Science Center, touch on communication and outreach activities, the consortium organisation and the life cycle assessment of X-IFU aiming at minimising the environmental footprint, associated with the development of the instrument. Thanks to the studies conducted so far on X-IFU, it is expected that along the design-to-cost exercise requested by ESA, the X-IFU will maintain flagship capabilities in spatially resolved high resolution X-ray spectroscopy, enabling most of the original X-IFU related scientific objectives of the Athena mission to be retained. The X-IFU will be provided by an international consortium led by France, The Netherlands and Italy, with ESA member state contributions from Belgium, Czech Republic, Finland, Germany, Poland, Spain, Switzerland, with additional contributions from the United States and Japan.The French contribution to X-IFU is funded by CNES, CNRS and CEA. This work has been also supported by ASI (Italian Space Agency) through the Contract 2019-27-HH.0, and by the ESA (European Space Agency) Core Technology Program (CTP) Contract No. 4000114932/15/NL/BW and the AREMBES - ESA CTP No.4000116655/16/NL/BW. This publication is part of grant RTI2018-096686-B-C21 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”. This publication is part of grant RTI2018-096686-B-C21 and PID2020-115325GB-C31 funded by MCIN/AEI/10.13039/501100011033

    FIRMS’ ENTRY CHOICES IN FOREIGN MARKETS: EMPIRICAL EVIDENCE FROM M.E.N.A.

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    The present paper addresses the factors influencing the firms’ choice of entry mode in international markets. In particular, the paper aims to explore two factors: one related to the external environment, and one dependent on firms. The first is the institutional context, intended as the whole of formal and informal rules of the country target. The second is the market commitment, intended as a construct of three factors: a) the resources committed in a particular market area, b) market knowledge meant as the result of the experience firms get in foreign market, c) and a general attitude of the decision makers to maintain the international presence for a long period of time. The theoretical analysis is completed by an empirical exploration performed by a Multiple Case Study analysis, of four European companies internationalized in the MENA. The results show that the kind of institutional context (hostile vs welcome) strongly impacts on the amount of resources involved in the internationalization process, while the level of market commitment (low vs high) impacts more on the complexity – and intensity - of the process

    NEW TRENDS IN LUXURY GOODS CONSUMPTIONS. A CROSS-CULTURAL ANALYSIS

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    Luxury is a very subjective concept, strictly connected to the values and assumptions people use to orientate their choices and behaviors. Values are concepts or beliefs, which refer to desirable states or behaviors, and are used as standards or criteria to select or evaluate behavior and events (Schwartz, 1994). They impact on individuals’ perceptions and choices, and this happens both at an individual and at a collective level. Our study is a working progress paper as a first attempt to investigate the effects of cultural values on the demand of luxury goods, to answer the following questions: Does consumers’ perception of luxury goods vary across countries? Does culture affect this perception

    Does national culture affect firms’ technological innovation? A cross-country analysis

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    Purpose – Our paper aims at investigating how country culture affects firms’ innovative performance. Whilemany contributions are given on the effect of national culture on countries’ innovation, the effects of culture on firms’ innovation performances has not been explored so far. Our study aims at filling this gap, by investigating how culture affects both firms’ innovation capability and innovation rapidity. Design/methodology/approach – The research employs a quantitative methodology based on non parametric correlations analysis between Hofstede’s cultural dimensions and firm’s innovative performances. We focus on technological innovation, and limit the analysis to the five Hofstede's dimensions, which are usually employed in similar studies, that is: power distance, uncertainty avoidance, masculinity, individualism, and long-term orientation. We measure the correlation between each dimension, and three main indicators of firms’ innovation performances: the number of international patents (absolute, and relative), the distribution of patent, and the patents’ growth ratio, so to consider both firms’ innovation capability, and rapidity. Originality/value – Our paper gives an original contribution to the entrepreneurial culture approach. Most of the studies focus on the impact of national culture on innovative performance at a country level, and consider how cultural dimensions impact on national innovation, usually measured as the amount of national patents or as the R&D expenses per capita. Our paper focuses instead on firms, and investigates how cultural dimensions impact on firms’ innovation performances, and more specifically on firms’ capability to innovate, and on the rapidity of the innovation process. Practical implications –By evaluating how cultural dimensions impact on innovation, managers may decide in which countries to relocate their R & D activities or with which companies to cooperate to innovate. Policy makers can understand which cultural dimensions affect innovation in order to define their policy, and leverage the values, which have a positive impact on local firms’ attitude towards innovation, and on their inclination to protect their innovations

    Measurement of the branching fractions for Cabibbo-suppressed decays D+K+Kπ+π0D^{+}\to K^{+} K^{-}\pi^{+}\pi^{0} and D(s)+K+ππ+π0D_{(s)}^{+}\to K^{+}\pi^{-}\pi^{+}\pi^{0} at Belle

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    International audienceWe present measurements of the branching fractions for the singly Cabibbo-suppressed decays D+K+Kπ+π0D^+\to K^{+}K^{-}\pi^{+}\pi^{0} and Ds+K+ππ+π0D_s^{+}\to K^{+}\pi^{-}\pi^{+}\pi^{0}, and the doubly Cabibbo-suppressed decay D+K+ππ+π0D^{+}\to K^{+}\pi^{-}\pi^{+}\pi^{0}, based on 980 fb1{\rm fb}^{-1} of data recorded by the Belle experiment at the KEKB e+ee^{+}e^{-} collider. We measure these modes relative to the Cabibbo-favored modes D+Kπ+π+π0D^{+}\to K^{-}\pi^{+}\pi^{+}\pi^{0} and Ds+K+Kπ+π0D_s^{+}\to K^{+}K^{-}\pi^{+}\pi^{0}. Our results for the ratios of branching fractions are B(D+K+Kπ+π0)/B(D+Kπ+π+π0)=(11.32±0.13±0.26)%B(D^{+}\to K^{+}K^{-}\pi^{+}\pi^{0})/B(D^{+}\to K^{-}\pi^{+}\pi^{+}\pi^{0}) = (11.32 \pm 0.13 \pm 0.26)\%, B(D+K+ππ+π0)/B(D+Kπ+π+π0)=(1.68±0.11±0.03)%B(D^{+}\to K^{+}\pi^{-}\pi^{+}\pi^{0})/B(D^{+}\to K^{-}\pi^{+}\pi^{+}\pi^{0}) = (1.68 \pm 0.11\pm 0.03)\%, and B(Ds+K+ππ+π0)/B(Ds+K+Kπ+π0)=(17.13±0.62±0.51)%B(D_s^{+}\to K^{+}\pi^{-}\pi^{+}\pi^{0})/B(D_s^{+}\to K^{+}K^{-}\pi^{+}\pi^{0}) = (17.13 \pm 0.62 \pm 0.51)\%, where the uncertainties are statistical and systematic, respectively. The second value corresponds to (5.83±0.42)×tan4θC(5.83\pm 0.42)\times\tan^4\theta_C, where θC\theta_C is the Cabibbo angle; this value is larger than other measured ratios of branching fractions for a doubly Cabibbo-suppressed charm decay to a Cabibbo-favored decay. Multiplying these results by world average values for B(D+Kπ+π+π0)B(D^{+}\to K^{-}\pi^{+}\pi^{+}\pi^{0}) and B(Ds+K+Kπ+π0)B(D_s^{+}\to K^{+}K^{-}\pi^{+}\pi^{0}) yields B(D+K+Kπ+π0)=(7.08±0.08±0.16±0.20)×103B(D^{+}\to K^{+}K^{-}\pi^{+}\pi^{0})= (7.08\pm 0.08\pm 0.16\pm 0.20)\times10^{-3}, B(D+K+ππ+π0)=(1.05±0.07±0.02±0.03)×103B(D^{+}\to K^{+}\pi^{-}\pi^{+}\pi^{0})= (1.05\pm 0.07\pm 0.02\pm 0.03)\times10^{-3}, and B(Ds+K+ππ+π0)=(9.44±0.34±0.28±0.32)×103B(D_s^{+}\to K^{+}\pi^{-}\pi^{+}\pi^{0}) = (9.44\pm 0.34\pm 0.28\pm 0.32)\times10^{-3}, where the third uncertainty is due to the branching fraction of the normalization mode. The first two results are consistent with, but more precise than, the current world averages. The last result is the first measurement of this branching fraction

    Measurement of the B+/B0B^+/B^0 production ratio in e+ee^+e^- collisions at the Υ(4S)\Upsilon(4S) resonance using BJ/ψ()KB \rightarrow J/\psi(\ell\ell) K decays at Belle

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    We measure the ratio of branching fractions for the Υ(4S)\Upsilon (4S) decays to B+BB^+B^- and B0Bˉ0B^0\bar{B}{}^0 using B+J/ψ()K+B^+ \rightarrow J/\psi(\ell\ell) K^+ and B0J/ψ()K0B^0 \rightarrow J/\psi(\ell\ell) K^0 samples, where J/ψ()J/\psi(\ell\ell) stands for J/ψ+J/\psi \to \ell^+\ell^- (=e\ell = e or μ\mu), with 711711 fb1^{-1} of data collected at the Υ(4S)\Upsilon(4S) resonance with the Belle detector. We find the decay rate ratio of Υ(4S)B+B\Upsilon(4S) \rightarrow B^+B^- over Υ(4S)B0Bˉ0\Upsilon(4S) \rightarrow B^0\bar{B}{}^0 to be 1.065±0.012±0.019±0.0471.065\pm0.012\pm 0.019 \pm 0.047, which is the most precise measurement to date. The first and second uncertainties are statistical and systematic, respectively, and the third uncertainty is systematic due to the assumption of isospin symmetry in BJ/ψ()KB \to J/\psi(\ell\ell) K
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