The LHCb trigger and data acquisition system

The LHCb experiment is the most recently approved of the 4 experiments under construction at CERNs LHC accelerator. It is a special purpose experiment designed to precisely measure the CP violation parameters in the B-B system. Triggering poses special problems since the interesting events containing B-mesons are immersed in a large background of inelastic p-p reactions. We therefore decided to implement a 4 level triggering scheme. The LHCb Data Acquisition (DAQ) system will have to cope with an average trigger rate of ~40 kHz, after two levels of hardware triggers, and an average event size of ~100 kB. Thus an event-building network which can sustain an average bandwidth of 4 GB/s is required. A powerful software trigger farm will have to be installed to reduce the rate from the 40 kHz to ~100 Hz of events written to permanent storage. In this paper we outline the general architecture of the Trigger and DAQ system and the readout protocols we plan to implement. First results of simulations of the behavior of the event- building network implementations under the expected traffic patterns are presented. (8 refs)

Valorisation of a water hyacinth in vermicomposting using an epigeic earthworm Perionyx excavatus in Central Vietnam

The feasibility of vermicomposting water hyacinth (WH) [Eichhornia crassipes (Mart.) Solms] mixed with pig manure (PM) in different proportions was tested using tropical composting earthworm Perionyx excavatus. Earthworms grew and reproduced normally until the incorporation of 50% WH in initial substrate. Higher water hyacinth proportions induced earthworms' mortality and significantly affected the numbers of hatchlings and cocoons produced during vermicomposting period. The influence of the application of compost/vermicompost obtained from water hyacinth mixed with pig manure was also studied on seeds germination. Only water hyacinth substrate with 25% WH + 75% PM enhanced seeds germination for Oryza sp. and Nasturtium officinale. At the end of experiments, a significant decrease was observed in organic carbon content for each tested substrates (S1 to S8), in total nitrogen (N) for substrates containing 70% to 100% of water hyacinth (S5 to S3) and compost substrates (S1 and S2). An important decrease was also noted in total potassium for all vermicompost substrates (S3 to S8), in total magnesium for composted substrates (S1 and S2), and in C/N ratio for substrates containing 0% to 50% of water hyacinth (S8 to S6). Whereas total N in vermicompost containing 0% to 50% of water hyacinth (S8 to S6), total phosphorus, total potassium in composted substrates (S1 and S2), total magnesium in vermicompost substrates (S3 to S8) and C:N ratio in substrates containing 70% to 100% of water hyacinth (S5 to S3) expressed a significant increase after eight weeks. The result suggested that water hyacinth could be potentially useful as raw material in vermicomposting and biofertilizing if mixed with 75% of pig manure

An Overview of the 13:8 Mean Motion Resonance between Venus and Earth

It is known since the seminal study of Laskar (1989) that the inner planetary system is chaotic with respect to its orbits and even escapes are not impossible, although in time scales of billions of years. The aim of this investigation is to locate the orbits of Venus and Earth in phase space, respectively to see how close their orbits are to chaotic motion which would lead to unstable orbits for the inner planets on much shorter time scales. Therefore we did numerical experiments in different dynamical models with different initial conditions -- on one hand the couple Venus-Earth was set close to different mean motion resonances (MMR), and on the other hand Venus' orbital eccentricity (or inclination) was set to values as large as e = 0.36 (i = 40deg). The couple Venus-Earth is almost exactly in the 13:8 mean motion resonance. The stronger acting 8:5 MMR inside, and the 5:3 MMR outside the 13:8 resonance are within a small shift in the Earth's semimajor axis (only 1.5 percent). Especially Mercury is strongly affected by relatively small changes in eccentricity and/or inclination of Venus in these resonances. Even escapes for the innermost planet are possible which may happen quite rapidly.Comment: 14 pages, 11 figures, submitted to CMD

A modern network approach to revisiting the positive and negative affective schedule (PANAS) construct validity

Introduction: The factor structure of the Positive and Negative Affective Schedule (PANAS) is still a topic of debate. There are several reasons why using Exploratory Graph Analysis (EGA) for scale validation is advantageous and can help understand and resolve conflicting results in the factor analytic literature. Objective: The main objective of the present study was to advance the knowledge regarding the factor structure underlying the PANAS scores by utilizing the different functionalities of the EGA method. EGA was used to (1) estimate the dimensionality of the PANAS scores, (2) establish the stability of the dimensionality estimate and of the item assignments into the dimensions, and (3) assess the impact of potential redundancies across item pairs on the dimensionality and structure of the PANAS scores. Method: This assessment was carried out across two studies that included two large samples of participants. Results and Conclusion: In sum, the results are consistent with a two-factor oblique structure.Fil: Flores Kanter, Pablo Ezequiel. Universidad Empresarial Siglo XXI; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Garrido, Luis Eduardo. Pontificia Universidad Católica Madre y Maestra; República DominicanaFil: Moretti, Luciana Sofía. Universidad Empresarial Siglo XXI; Argentina. Pontificia Universidad Católica Madre y Maestra; República Dominicana. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Medrano, Leonardo. Universidad Empresarial Siglo XXI; Argentina. Pontificia Universidad Católica Madre y Maestra; República Dominicana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

International money markets: eurocurrencies

Eurocurrencies are international markets for short-term wholesale bank deposits and loans. They emerged in Western Europe in the late 1950s and rapidly reached a global scale. A Eurocurrency is a form of bank money: an unsecured short-term bank debt denominated in a currency (for instance, US dollars) but issued by banks operating offshore, in a geographical location or a legal space situated outside of the jurisdiction of the national authorities presiding over that currency (for instance, the Federal Reserve). In Eurocurrency markets, banks intermediate mainly between foreign residents. They borrow funds by "accepting" foreign currency deposits and lend foreign currency-denominated funds by "placing" deposits with other banks, by granting short-term loans or investing in other liquid assets. Historically, Eurodollars accounted for the largest share of Eurocurrencies, although other international currencies (Deutsche Marks, Japanese yens, and especially Euros since 1999) played an important role. Eurocurrency markets were a manifestation of financial integration and interdependence in a globalizing economy and performed critical functions in the distribution and creation of international liquidity. At the same time, their fast growth was a recurrent source of concerns for central bankers and policymakers due to their implications for macroeconomic policies and financial stability. This chapter analyzes different aspects of the historical development of Eurocurrency markets and their role in the international monetary and financial system. The first part discusses theoretical interpretations, presents estimates of markets' size, describes their structure, and explains the determinants of their growth. The second part analyzes the spread between Eurodollar rates and other US money market rates, the role of arbitrage, the evolution of risk factors, and the causes of historical episodes of stress and contagion in the interbank market. The last part discusses political economy issues, such as the role of governments and market forces in the emergence of Eurodollars in the 1950s and the failed attempts to impose multilateral controls on Eurocurrency markets in the 1970s

WA92: a fixed target experiment to trigger on and identify beauty particle decays

We describe the detectors and trigger system used in the CERN WA92 experiment. The experiment was designed to study the production and decay of beauty particles from 350 GeV/$c\,$ $\,\pi^-$ interactions in copper and tungsten targets. Charged particle tracking is performed using the Omega spectrometer. Silicon microstrip detectors are used to provide precise tracking information in the region of the production and the decay of heavy-flavoured particles and to trigger on the resulting high impact parameter tracks. The precision of vertex reconstruction corresponds to $\pm 3.7\%$ of the mean B-decay proper lifetime. Lepton and high transverse momentum hadron signals are also used in the trigger, which accepts 29\% of B-decays and rejects 98\% of non-beauty interactions

Measurement of the beauty production cross-section in 350 GeV/c π−\pi^- -Cu interactions

Using a sample of $10^8$ triggered events, produced in $\pi^-$--$\,$Cu interactions at 350~GeV$/c$, we have identified 26 beauty events. The estimated background in this sample is $0.6 \pm 0.6$ events. From these data, assuming a linear A-dependence, we measure a beauty production cross-section integrated over all $x_F$ of $5.7 {+1.3 \atop -1.1}~{\mathrm {(stat.)}} {+0.6 \atop -0.5}~{\mathrm {(syst.)}}~$nb/N