Search

Your search keyword '"Andresen, G. B."' showing total 7 results
Start Over Author "Andresen, G. B." Database OpenAIRE
7 results on '"Andresen, G. B."'

1. Antihydrogen and mirror-trapped antiproton discrimination: Discriminating between antihydrogen and mirror-trapped antiprotons in a minimum-B trap

Author

Amole, C., Andresen, G. B., Ashkezari, M. D., Baquero-Ruiz, M., Bertsche, W., Butler, E., Cesar, C. L., Chapman, S., Charlton, M., Deller, A., Eriksson, S., Fajans, J., Friesen, T., Fujiwara, M. C., Gill, D. R., Gutierrez, A., Hangst, J. S., Hardy, W. N., Hayden, M. E., Humphries, A. J., Hydomako, R., Kurchaninov, L., Jonsell, S., Madsen, N., Menary, S., Nolan, P., Olchanski, K., Olin, A., Povilus, A., Pusa, P., Robicheaux, F., Sarid, E., Silveira, D. M., So, C., Storey, J. W., Thompson, R. I., van der Werf, D. P., and Wurtele, J. S.

Subjects
Condensed Matter::Quantum Gases, Plasma Physics (physics.plasm-ph), Physics::General Physics, High Energy Physics - Experiment (hep-ex), Atomic Physics (physics.atom-ph), Physics::Accelerator Physics, FOS: Physical sciences, Physics::Atomic Physics, Nuclear Experiment (nucl-ex), Nuclear Experiment, Physics - Plasma Physics, Physics - Atomic Physics, High Energy Physics - Experiment
Abstract

Recently, antihydrogen atoms were trapped at CERN in a magnetic minimum (minimum-B) trap formed by superconducting octupole and mirror magnet coils. The trapped antiatoms were detected by rapidly turning off these magnets, thereby eliminating the magnetic minimum and releasing any antiatoms contained in the trap. Once released, these antiatoms quickly hit the trap wall, whereupon the positrons and antiprotons in the antiatoms annihilated. The antiproton annihilations produce easily detected signals; we used these signals to prove that we trapped antihydrogen. However, our technique could be confounded by mirror-trapped antiprotons, which would produce seemingly-identical annihilation signals upon hitting the trap wall. In this paper, we discuss possible sources of mirror-trapped antiprotons and show that antihydrogen and antiprotons can be readily distinguished, often with the aid of applied electric fields, by analyzing the annihilation locations and times. We further discuss the general properties of antiproton and antihydrogen trajectories in this magnetic geometry, and reconstruct the antihydrogen energy distribution from the measured annihilation time history., Comment: 17 figures

Published
2012
Full Text
View/download PDF

2. Fundamental properties of and transition to a fully renewable pan-European power system

Author

Andresen, G. B., Rasmussen, M. G., Rodriguez, R. A., Becker, S., and Greiner, M.

Abstract

We introduce a top-down stylized model to analyse the impact of a transition to a European power system based only on wind and solar power. Wind and solar power generation is calculated from high-resolution weather data and based on the country specific electricity demand alone, we introduce a model of the conventional power system that facilitates simple spatio-temporal modelling of its macroscopic behaviour without direct reference to the underlying technological, economical, and political development in the system. Using this model, we find that wind and solar power generation can replace conventional power generation and power capacity to a large degree if power transmission across the continent is made possible.

Published
2012
Full Text
View/download PDF

3. ALPHA ANTIHYDROGEN EXPERIMENT

Author

ALPHA Collaboration, Fujiwara, M. C., Andresen, G. B., Ashkezari, M. D., Baquero-Ruiz, M., Bertsche, W., Bray, C. C., Butler, E., Cesar, C. L., Chapman, S., Charlton, M., Fajans, J., Friesen, T., Gill, D. R., Hangst, J. S., Hardy, W. N., Hayano, R. S., Hayden, M. E., Humphries, A. J., Hydomako, R., Jonsell, S., Kurchaninov, L., Lambo, R., Madsen, N., Menary, S., Nolan, P., Olchanski, K., Olin, A., Povilus, A., Pusa, P., Robicheaux, F., Sarid, E., Silveira, D. M., So, C., Storey, J. W., Thompson, R. I., van der Werf, D. P., Wilding, D., Wurtele, J. S., and Yamazaki, Y.

Subjects
Condensed Matter::Quantum Gases, Physics, Physics::General Physics, Atomic Physics (physics.atom-ph), FOS: Physical sciences, Alpha (ethology), Physics - Plasma Physics, High Energy Physics - Experiment, Physics - Atomic Physics, 3. Good health, Plasma Physics (physics.plasm-ph), Nuclear physics, High Energy Physics - Phenomenology, High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), Physics::Atomic and Molecular Clusters, Nuclear Physics - Experiment, Physics::Atomic Physics, Nuclear Experiment (nucl-ex), Antihydrogen, Nuclear Experiment
Abstract

ALPHA is an experiment at CERN, whose ultimate goal is to perform a precise test of CPT symmetry with trapped antihydrogen atoms. After reviewing the motivations, we discuss our recent progress toward the initial goal of stable trapping of antihydrogen, with some emphasis on particle detection techniques., Comment: Invited talk presented at the Fifth Meeting on CPT and Lorentz Symmetry, Bloomington, Indiana, June 28-July 2, 2010

Published
2010
Full Text
View/download PDF

4. Evaporative cooling of antiprotons to cryogenic temperatures

Author

ALPHA Collaboration, Andresen, G. B., Ashkezari, M. D., Baquero-Ruiz, M., Bertsche, W., Bowe, P. D., Butler, E., Cesar, C. L., Chapman, S., Charlton, M., Fajans, J., Friesen, T., Fujiwara, M. C., Gill, D. R., Hangst, J. S., Hardy, W. N., Hayano, R. S., Hayden, M. E., Humphries, A., Hydomako, R., Jonsell, S., Kurchaninov, L., Lambo, R., Madsen, N., Menary, S., Nolan, P., Olchanski, K., Olin, A., Povilus, A., Pusa, P., Robicheaux, F., Sarid, E., Silveira, D. M., So, C., Storey, J. W., Thompson, R. I., van der Werf, D. P., Wilding, D., Wurtele, J. S., and Yamazaki, Y.

Subjects
Accelerator Physics (physics.acc-ph), Atomic Physics (physics.atom-ph), Other Fields of Physics, Evaporation, FOS: Physical sciences, General Physics and Astronomy, Cryogenics, 7. Clean energy, 01 natural sciences, High Energy Physics - Experiment, Physics - Atomic Physics, 010305 fluids & plasmas, Nuclear physics, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, Physics::Atomic Physics, Nuclear Experiment (nucl-ex), 010306 general physics, Antihydrogen, Nuclear Experiment, Physics, Plasma, Physics - Plasma Physics, Charged particle, Plasma Physics (physics.plasm-ph), Antiproton, Antimatter, Physics - Accelerator Physics, Evaporative cooler
Abstract

We report the application of evaporative cooling to clouds of trapped antiprotons, resulting in plasmas with measured temperature as low as 9~K. We have modeled the evaporation process for charged particles using appropriate rate equations. Good agreement between experiment and theory is observed, permitting prediction of cooling efficiency in future experiments. The technique opens up new possibilities for cooling of trapped ions and is of particular interest in antiproton physics, where a precise \emph{CPT} test on trapped antihydrogen is a long-standing goal., Comment: 5 pages, 4 figures

Published
2010
Full Text
View/download PDF

5. Search for trapped antihydrogen: First candidate events

Author

Hydomako, R., Andresen, G. B., Ashkezari, M. D., Baquero-Ruiz, M., Bertsche, W., Bowe, P. D., Bray, C. C., Butler, E., Cesar, C. L., Chapman, S., Charlton, M., Fajans, J., Timothy Friesen, Fujiwara, M. C., Gill, D. R., Hangst, J. S., Hardy, W. N., Hayano, R. S., Hayden, M. E., Humphries, A. J., Jonsell, S., Jørgensen, L. V., Kurchaninov, L., Lambo, R., Madsen, N., Menary, S., Nolan, P., Olchanski, K., Olin, A., Povilus, A., Pusa, P., Robicheaux, F., Sarid, E., Seif El Nasr-Storey, S., Silveira, D. M., So, C., Storey, J. W., Thompson, R. I., Werf, D. P., Wilding, D., Wurtele, J. S., and Yamazaki, Y.

6. Antimatter plasmas used for antihydrogen formation

Author

Andresen, G. B., Ashkezari, M. D., Baquero-Ruiz, M., Bertsche, W., Bowe, P. D., Butler, E., Cesar, C. L., Chapman, S., Charlton, M., Fajans, J., Friesen, T., Fujiwara, M. C., Gill, D. R., Hangst, J. S., Hardy, W. N., Ryugo Hayano, Hayden, M. E., Humphries, A. J., Hydomako, R., Jørgensen, L. V., Kurchaninov, L., Lambo, R., Madsen, N., Nolan, P., Olchanski, K., Olin, A., Povilus, A., Pusa, P., Robicheaux, F., Sarid, E., Silveira, D. M., Storey, J. W., So, C., Thompson, R. I., Werf, D. P., Wilding, D., Wurtele, J. S., and Yamazaki, Y.

Catalog

Books, media, physical & digital resources
See catalog results