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A precise calibration of the jet energy in the ATLAS experiment at LHC is fundamental for many physics issues. Di-jet and multi jet events will be used to cross-check the relative response across different pseudo-rapidity and tran...
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A precise calibration of the jet energy in the ATLAS experiment at LHC is fundamental for many physics issues. Di-jet and multi jet events will be used to cross-check the relative response across different pseudo-rapidity and transverse momentum regions. The photon+jet channel (being the one with largest cross section) is the first candidate to check in situ the jet absolute energy scale. In events with photon and a recoiling jet, the transverse momentum balance can be exploited to estimate the jet energy using the measurement on the photon, whose scale is much better under control. The main background to this channel is given by QCD events where one jet is misidentified as a photon. The status of this analysis with the data collected by ATLAS in 2010 will be presented.
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The national temperature standard for the low-temperature range between 13.8033 K and 273.16 K has been established in Poland at the Institute of Low Temperature and Structure Research (INTiBS). The standard consists of sealed cel...
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The national temperature standard for the low-temperature range between 13.8033 K and 273.16 K has been established in Poland at the Institute of Low Temperature and Structure Research (INTiBS). The standard consists of sealed cells for realization of six fixed points of the International Temperature Scale of 1990 (ITS-90) in the low-temperature range, an adiabatic cryostat and Isotech water and mercury triple-point baths, capsule standard resistance thermometers (CSPRT), and AC and DC bridges with standard resistors for thermometers resistance measurements. INTiBS calibrates CSPRTs at the low-temperature fixed points with uncertainties less than 1 mK. In lower temperature range - between 2.5 K and about 25 K - rhodiumiron (RhFe) resistance thermometers are calibrated by comparison with a standard which participated in the EURAMET.T-K1.1 comparison. INTiBS offers a calibration service for industrial platinum resistance thermometers and for digital thermometers between 77 K and 273 K. These types of thermometers may be calibrated at INTiBS also in a higher temperature range up to 550℃. The Laboratory of Temperature Standard at INTiBS acquired an accreditation from the Polish Centre for Accreditation. A management system according to EN ISO/IEC 17025:2005 was established at the Laboratory and presented on EURAMET QSM Forum.
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In two earlier articles (Tappin, Eyles and Davies in Solar Phys. 290, 2143, 2015, and Solar Phys. 292, 28, 2017), we used the stellar photometry to determine the calibration parameters and long-term trends of the Heliospheric Imag...
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In two earlier articles (Tappin, Eyles and Davies in Solar Phys. 290, 2143, 2015, and Solar Phys. 292, 28, 2017), we used the stellar photometry to determine the calibration parameters and long-term trends of the Heliospheric Imagers (HI) on board the Solar Terrestrial Relations Observatory (STEREO). In this article we provide an update on these determinations for the ahead spacecraft (STEREO-A) to incorporate the interval after solar superior conjunction (when STEREO-B was non-operational). We describe the modifications needed to our photometry procedures to accommodate the reduced pointing stability following the switch-off of the spacecraft gyros shortly prior to conjunction. We find a small revision to the absolute levels is required. We also show that the very low rates of degradation (less than 0.2% per year) found in the earlier determinations have continued beyond solar conjunction.
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Transgressive-regressive cycles are recognized in early to middle Pleistocene siliciclastic shelf sediments that crop out in the tectonically active Crotone basin (southern Italy). Chronological constraints from calcareous nannofo...
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Transgressive-regressive cycles are recognized in early to middle Pleistocene siliciclastic shelf sediments that crop out in the tectonically active Crotone basin (southern Italy). Chronological constraints from calcareous nannofossil biostratigraphy and magnetostratigraphy indicate that these cycles are synchronous with oxygen isotope stages 19 to 33 and hence with global sea-level fluctuations. A major facies break in the succession correlates with oxygen isotope stages 22-24, corresponding to the major mid-Pleistocene climatic shift. These findings indicate that Pleistocene eustatic oscillations can be recognized in the lithostratigraphy of a tectonically active siliciclastic shelf setting. By integrating biomagnetostratigraphy with physical stratigraphy, a highly resolved chronology can be developed for these settings similar to that available for deep-sea sediments. [References: 13]
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EXCELLENT preservation of wood and charcoal at archaeological sites in Anatolia has allowed the Aegean Dendrochronology Project to build absolute and floating tree-ring sequences(1). One such floating dendrochronology of 1,503 yea...
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EXCELLENT preservation of wood and charcoal at archaeological sites in Anatolia has allowed the Aegean Dendrochronology Project to build absolute and floating tree-ring sequences(1). One such floating dendrochronology of 1,503 years includes samples relating to known rulers, sites and cultures of the ancient eastern Mediterranean. If this chronology could be dated precisely, many long-standing questions might be resolved. Here we report 18 high-precision C-14 determinations which, when wiggle-matched to the radiocarbon calibration curve, provide a date within narrow limits. Inside this range, we can suggest the probable absolute dating of the dendrochronology because of a remarkable growth anomaly in the seventeenth century BC, for which we propose a correlation with major growth anomalies at 1628/1627 BC in the absolutely dated dendrochronologies of Europe and the United States. Many archaeological sites from several cultures in the eastern Mediterranean can now be dated with fine precision. This chronology has important implications for Old World archaeology and prehistory. [References: 30]
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The reference frame of a global terrestrial network is defined by the origin, the orientation and the scale. The origin of the ITRF2014 is defined by the ILRS long-term solution, the orientation by no-net rotation conditions w.r.t...
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The reference frame of a global terrestrial network is defined by the origin, the orientation and the scale. The origin of the ITRF2014 is defined by the ILRS long-term solution, the orientation by no-net rotation conditions w.r.t. the previous reference frame (ITRF2008), and the scale by the mean values from global VLBI and SLR solution series (Altamimi et al. in J Geophys Res Solid Earth 121:6109-6131, 2016). With the release of the Galileo satellite antenna phase center offsets (PCO) w.r.t. the satellites center of mass (GSA in Galileo IOV and FOC satellite metadata, 2019) and the availability of new ground antenna calibrations for GNSS receivers, based on anechoic chamber measurements or on robot calibrations, GNSS global network solutions qualify to contribute to the scale determination of terrestrial networks, as well. Our analysis is based on global multi-GNSS solutions of the years 2017 and 2018 and may be seen as "proof of concept" for the contribution of GNSS data to the scale determination of the terrestrial reference frame. In a first step, the currently used Galileo PCO estimations (Steigenberger et al. in J Geod 90:773-785, 2016) are compared to the released PCO values, which show discrepancies on the decimeter-level. Eventually, the published Galileo PCOs are used in an experimental solution as known values. GNSS-specific PCOs are estimated, as well, for GPS and GLONASS, together with the "standard" parameters set up in global GNSS solutions. From the estimated network coordinates, a time series of daily scale parameters of the terrestrial network is extracted, which shows an offset of the order of 1 ppb (parts per billion, corresponding to a height difference of 6.4 mm on the Earth's surface) w.r.t. to the ITRF2014 network and an annual variation with an amplitude of about 0.3 ppb.
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A class of new wind speed scales is proposed in which the relevant scaling factors are derived from physical quantities like mass flux density, energy density (pressure), or energy flux density. Hence, they are called Energy- or E...
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A class of new wind speed scales is proposed in which the relevant scaling factors are derived from physical quantities like mass flux density, energy density (pressure), or energy flux density. Hence, they are called Energy- or E-scales, and can be applied to wind speeds of any intensity. It is shown that the Mach scale is a special case of an E-scale. Aside from its foundation in physical quantities which allow for a calibration of the scales, the E-scale concept can help to overcome the present plethora of scales for winds in the range from gale to hurricane intensity. A procedure to convert existing data based on the Fujita-scale or other scales (Saffir-Simpson, TORRO, Beaufort) to their corresponding E-scales is outlined.
Even for the large US tornado record, the workload of conversion in case of an adoption of the E-scale would in principle remain manageable (if the necessary metadata to do so were available), as primarily the F5 events would have to be re-rated. Compared to damage scales like the "Enhanced Fujita" or EF-scale concept recently implemented in the USA, the E-scales are based on first principles. They can consistently be applied all over the world for the purpose of climatological homogeneity.
To account for international variations in building characteristics, one should not adapt wind speed scale thresholds to certain national building characteristics. Instead, one worldwide applicable wind speed scale based on physical principles should rather be complemented by nationally-adapted damage descriptions. The E-scale concept can provide the basis for such a standardised wind speed scale.
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The aim of this paper is to calculate an accurate large-scale flatfield for the STEREO HI-1 instruments. This is done by analysing the variation in intensity of stars in the background starfield as they pass across the CCD. In ord...
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The aim of this paper is to calculate an accurate large-scale flatfield for the STEREO HI-1 instruments. This is done by analysing the variation in intensity of stars in the background starfield as they pass across the CCD. In order to use the background starfield, a photometric calibration is performed which defines a HI magnitude scale and a conversion between this scale and measured intensity. The photometric calibration uses stellar spectra folded through the instrument response to make initial intensity predictions. However, a secondary prediction method based on the photometric calibration, which blends the R-, V- and B-magnitudes of a star, is derived for stars with no spectral information.
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Investigation of colluvial, fluvial and lacustrine sediment archives from 12 sites in Germany for the last ca 5000 years demonstrates that there is no synchronous development of the cultural landscape. This can only be explained, ...
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Investigation of colluvial, fluvial and lacustrine sediment archives from 12 sites in Germany for the last ca 5000 years demonstrates that there is no synchronous development of the cultural landscape. This can only be explained, if climate is not the dominating control mechanism. However, to a certain degree there is a climatic influence, like during the slight climatic deteriorations immediately following the Holocene climatic optimum, or the stronger ones during the 1st millennium BC and during the Little Ice Age. As shown by all the different archives, human impact strongly increased and became the dominant factor which often made the climatic influence difficult to detect or even invisible. There are indications that human activities may have been triggered by climatic changes. Although the pattern of habitation was in general dependent on the environment offered by nature, also political and socio-economic factors have been involved, resulting in varying occupation patterns in prehistoric and medieval times. (C) 2002 Elsevier Science Ltd. All rights reserved. [References: 49]
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The Soil Water Assessment Tool (SWAT) was applied to the 2,530 km~2 Chaliyar river basin in Kerala, India to investigate the influence of scale on the model parameters. The study was carried out in this river basin at two scales. ...
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The Soil Water Assessment Tool (SWAT) was applied to the 2,530 km~2 Chaliyar river basin in Kerala, India to investigate the influence of scale on the model parameters. The study was carried out in this river basin at two scales. Parameters such as land use, soil type, topography and management practices are similar at these scales. The model was initially calibrated for streamflow and then validated. Critical parameters were the curve number (CN2), soil evaporation compensation factor (ESCO), available water holding capacity (SOL_AWC), average slope length (SLSUBBSN), and base flow alpha factor (ALPHA_BF). Using the optimized value of various parameters, stream flow was estimated from parts of the basin at two different scales-an area of 2,361.58 km~2 and an area of 1,013.15 km~2. The streamflow estimates at both these scales were statistically analysed by computing the coefficient of determination (R~2) and the Nash-Sutciiffe efficiency (E_(NS)). Results indicate that the SWAT model could simulate streamflow at both scales reasonably well with very little difference between the observed and computed values. However, the results also indicate that there may be greater uncertainty in SWAT streamflow estimates as the size of the watershed increases.
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