20 research outputs found
The performance of the jet trigger for the ATLAS detector during 2011 data taking
The performance of the jet trigger for the ATLAS detector at the LHC during the 2011 data taking period is described. During 2011 the LHC provided proton–proton collisions with a centre-of-mass energy of 7 TeV and heavy ion collisions with a 2.76 TeV per nucleon–nucleon collision energy. The ATLAS trigger is a three level system designed to reduce the rate of events from the 40 MHz nominal maximum bunch crossing rate to the approximate 400 Hz which can be written to offline storage. The ATLAS jet trigger is the primary means for the online selection of events containing jets. Events are accepted by the trigger if they contain one or more jets above some transverse energy threshold. During 2011 data taking the jet trigger was fully efficient for jets with transverse energy above 25 GeV for triggers seeded randomly at Level 1. For triggers which require a jet to be identified at each of the three trigger levels, full efficiency is reached for offline jets with transverse energy above 60 GeV. Jets reconstructed in the final trigger level and corresponding to offline jets with transverse energy greater than 60 GeV, are reconstructed with a resolution in transverse energy with respect to offline jets, of better than 4 % in the central region and better than 2.5 % in the forward direction
Mining in Papua New Guinea: A complex story of trends, impacts and governance
Mining is often portrayed as a contributor to sustainable development, especially so in developing countries such as Papua New Guinea (PNG). Since 1970, several large mines have been developed in PNG (e.g. Panguna, Ok Tedi, Porgera, Lihir, Ramu) but always with controversial environmental standards and social impacts often overlooked or ignored. In PNG, mine wastes are approved to be discharged to rivers or oceans on a very large scale, leading to widespread environmental and social impacts – to the point of civil war in the case of Panguna. The intimate links between indigenous communities and their environment have invariably been under-estimated or ignored, leading many to question mining's role in PNG's development. Here, we review the geology of PNG, its mineral resources, mining history, key trends for grades and resources, environmental metrics (water, energy, carbon), mine waste management, and regulatory and governance issues. The study provides a unique and comprehensive insight into the sustainable development contribution of the mining industry in PNG – especially the controversial practices of riverine and marine mine waste disposal. The history of mining is a complex story of the links between the anthroposphere, biosphere, hydrosphere and geosphere. Ultimately, this study demonstrates that the scale of environmental and social impacts and risks are clearly related to the vast scale of mine wastes – a fact which remains been poorly recognised. For PNG, the promise of mining-led development remains elusive to many communities and they are invariably left with significant social and environmental legacies which will last for decades to centuries (e.g. mine waste impacts on water resources). Most recently, the PNG government has moved to ban riverine tailings disposal for future projects and encourage greater transparency and accountability by the mining sector, including its interactions with communities. There remains hope for better outcomes in the future
Data for: Global-scale mapping and prediction of mine areas
Mine Production and GIS Data associated with the paper "Global-scale remote sensing of mines and analysis of factors explaining their extent