The ALICE collaboration is investigating single, double and central diffractive processes in pp interactions. The single and double diffractive cross-sections are presented at 900 GeV 2.76 TeV and 7 ...TeV using an analysis method based on the classification of diffractive gaps. Promising early results on central diffractive processes have motivated the use of additional diffractive counters, which are currently being installed.
Hyperon polarization Baillie, O Villalobos
Journal of physics. G, Nuclear and particle physics,
06/2009, Letnik:
36, Številka:
6
Journal Article, Conference Proceeding
Recenzirano
In this paper, the Omega- hyperon is presented as an interesting candidate for polarization analyses, owing to the large polarization values that can be observed there. Practical difficulties arising ...from contamination are introduced, and discussed in the cases of the experiments currently listed as of relevance for Omega- spin studies.
What can we learn from spin? Villalobos Baillie, O
Journal of physics. G, Nuclear and particle physics,
04/2008, Letnik:
35, Številka:
4
Journal Article, Conference Proceeding
The ALICE Central Trigger Processor (CTP) at the CERN LHC has been upgraded for LHC Run 2, to improve the Transition Radiation Detector (TRD) data-taking efficiency and to improve the physics ...performance of ALICE. There is a new additional CTP interaction record sent using a new second Detector Data Link (DDL), a 2 GB DDR3 memory and an extension of functionality for classes. The CTP switch has been incorporated directly onto the new LM0 board. A design proposal for an ALICE CTP upgrade for LHC Run 3 is also presented. Part of the development is a low latency high bandwidth interface whose purpose is to minimize an overall trigger latency.
Photons produced in pp interactions at 450 GeV/c were detected by reconstructing the e+e− pairs of photon conversions in a 1 mm thick lead sheet placed in front of the MWPCs of the OMEGA spectrometer ...at CERN. A soft photon signal 4.1±0.8 times the inner bremsstrahlung prediction was observed in the forward rapidity region (yc.m.s.⩾1.2), thus extending the domain of the anomalous soft photon effect seen already in K+p, π+p and π−p interactions.
In the ALICE experiment, the Low-Voltage Differential Signalling (LVDS) format is used for the transmission of trigger inputs from the detectors to the Central Trigger Processor (CTP), the L0 trigger ...outputs from Local Trigger Units (LTU) boards back to the detectors and the BUSY inputs from the sub-detectors to the CTP. ALICE has designed a set-up, called the LVDS transmission tester, that aims to measure various transmission quality parameters and the bit-error rate (BER) for long period runs in an automatic way. In this paper, this method is described and the conclusions from these tests for the ALICE LVDS cables are discussed.
Strangeness production in the ALICE experiment Villalobos Baillie, O
Journal of physics. G, Nuclear and particle physics,
06/2005, Letnik:
31, Številka:
6
Journal Article, Conference Proceeding
The integration of the ALICE trigger system with sub-detectors Krivda, M.; Barnby, L.; Bombara, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2010, Letnik:
617, Številka:
1
Journal Article
Recenzirano
The ALICE Trigger electronics (TRG) has been installed in the experimental cavern and tested with each of the detectors, both individually (‘standalone’ mode) and in ‘global’ runs, i.e. those ...involving other detectors. Global runs were performed with cosmic ray triggers, and also during the LHC startup period in September 2008. In this paper the status of the trigger system will be reviewed, in particular describing recent extensions to the system.
The reaction pp -> pf (eta eta) ps has been studied at 450 GeV/c. For the first time a partial wave analysis of the centrally produced eta eta system has been performed. Signals for the f0(1500), ...f0(1710) and f2(2150) are observed and the decay branching fractions of these states are determined.