Azimuthal Angular Distributions in EDDE as Spin-Parity Analyser and Glueball Filter for LHC

Exclusive Double Diffractive Events (EDDE) are analysed as the source of information about the central system. Experimental possibilities for exotic particles searches are considered. From the reggeized tensor current picture some azimuthal angle dependences were obtained to fit the data from WA102 experiment and to make predictions for LHC collider.Comment: LaTeX, 20 pages, 7 figures, references are adde

Case Study of Non-Isolated MMC DC-DC Converter in HVDC Grids

Peer reviewedPublisher PD

Do Irrelevant Sounds Impair the Maintenance of All Characteristics of Speech in Memory?

Several studies have shown that maintaining in memory some attributes of speech, such as the content or pitch of an interlocutor's message, is markedly reduced in the presence of background sounds made of spectrotemporal variations. However, experimental paradigms showing this interference have only focused on one attribute of speech at a time, and thus differ from real-life situations in which several attributes have to be memorized and maintained simultaneously. It is possible that the interference is even greater in such a case and can occur for a broader range of background sounds. We developed a paradigm in which participants had to maintain the content, pitch and speaker size of auditorily presented speech information and used various auditory distractors to generate interference. We found that only distractors with spectrotemporal variations impaired the detection, which shows that similar interference mechanisms occur whether there are one or more speech attributes to maintain in memory. A high percentage of false alarms was observed with these distractors, suggesting that spectrotemporal variations not only weaken but also modify the information maintained in memory. Lastly, we found that participants were unaware of the interference. These results are similar to those observed in the visual modalit

Antimatter and Matter Production in Heavy Ion Collisions at CERN (The NEWMASS Experiment NA52)

Besides the dedicated search for strangelets NA52 measures light (anti)particle and (anti)nuclei production over a wide range of rapidity. Compared to previous runs the statistics has been increased in the 1998 run by more than one order of magnitude for negatively charged objects at different spectrometer rigidities. Together with previous data taking at a rigidity of -20 GeV/c we obtained 10^6 antiprotons 10^3 antideuterons and two antihelium3 without centrality requirements. We measured nuclei and antinuclei (p,d,antiprotons, antideuterons) near midrapidity covering an impact parameter range of b=2-12 fm. Our results strongly indicate that nuclei and antinuclei are mainly produced via the coalescence mechanism. However the centrality dependence of the antibaryon to baryon ratios show that antibaryons are diminished due to annihilation and breakup reactions in the hadron dense environment. The volume of the particle source extracted from coalescence models agrees with results from pion interferometry for an expanding source. The chemical and thermal freeze-out of nuclei and antinuclei appear to coincide with each other and with the thermal freeze-out of hadrons.Comment: 12 pages, 8 figures, to appear in the proceedings of the conference on 'Fundamental Issues in Elementary Matter' Bad Honnef, Germany, Sept. 25-29, 200

Assessment of interoperability in multi-vendor VSC-HVDC systems : interim results of the Best Paths DEMO #2

This paper describes the methodology and interim results from the ongoing European project Best Paths DEMO #2, which is the first attempt to undertake systematic investigation on interoperability in multi-vendor VSC-HVDC systems. The study is based on state-of-the-art technologies provided by three world-class HVDC vendors and involves TSOs and academics for investigations covering various HVDC layouts, from point-to-point to radial and meshed multi-terminal structures. The paper describes the methodology used to assess and maximize interoperability, which comprises two stages: the first one relies on electromagnetic transient (EMT) simulation tools, while the second and ongoing one relies on real-time simulation with actual control cubicles provided by HVDC vendors. The paper mainly reports on the different tasks which were carried out during the first stage (EMT simulations) and exhibits the results observed. The main tasks and results are listed as follows: - Commonly agreed definition of interoperability - Definition of common converter specifications for all involved HVDC vendors, based on the ENTSO-E Network Code for realism and replicability - Definition of 5 different DC systems (including DC grids) on which interoperability should be assessed - Provision of detailed vendor-specific EMT converter models, and their individual validation - Assessment of interoperability on more than 1.000 realistic scenarios, from which 15% are representative of actual interoperability issues between the vendors - First set of recommendations to maximize interoperability Finally, the paper provides insights on the second and ongoing stage of the project based on real-time simulation using actual vendor control cubicles for deeper investigations

Interference Alignment and Cancellation

The throughput of existing MIMO LANs is limited by the number of antennas on the AP. This paper shows how to overcome this limit. It presents interference alignment and cancellation (IAC), a new approach for decoding concurrent sender-receiver pairs in MIMO networks. IAC synthesizes two signal processing techniques, interference alignment and interference cancellation, showing that the combination applies to scenarios where neither interference alignment nor cancellation applies alone. We show analytically that IAC almost doubles the throughput of MIMO LANs. We also implement IAC in GNU-Radio, and experimentally demonstrate that for 2x2 MIMO LANs, IAC increases the average throughput by 1.5x on the downlink and 2x on the uplink.United States. Defense Advanced Research Projects Agency. Information Theory for Mobile Ad-Hoc Networks Progra