Search

Your search keyword '"Silveira, D.M"' showing total 17 results
Start Over Author "Silveira, D.M"
17 results on '"Silveira, D.M"'

1. Design and Performance of a Novel Low Energy Multi-Species Beamline for the ALPHA Antihydrogen Experiment

Author

Baker, C.J., Bertsche, W., Capra, A., Cesar, C.L., Charlton, M., Christensen, A.J., Collister, R., Cridland Mathad, A., Eriksson, S., Evans, A., Evetts, N., Fabbri, S., Fajans, J., Friesen, T., Fujiwara, M.C., Gill, D.R., Grandemange, P., Granum, P., Hangst, J.S., Hayden, M.E., Hodgkinson, D., Isaac, C.A., Johnson, M.A., Jones, J.M., Jones, S.A., Khramov, A., Kurchaninov, L., Madsen, N., Maxwell, D., McKenna, J.T.K., Menary, S., Momose, T., Mullan, P.S., Munich, J.J., Olchanski, K., Peszka, J., Powell, A., Rasmussen, C.O., Sacramento, R.L., Sameed, M., Sarid, E., Silveira, D.M., So, C., Starko, D.M., Stutter, G., Tharp, T.D., Thompson, R.I., Torkzaban, C., van der Werf, D.P., and Wurtele, J.S.

Subjects
Accelerator Physics (physics.acc-ph), FOS: Physical sciences, Physics - Accelerator Physics, Accelerators and Storage Rings
Abstract

The ALPHA Collaboration, based at the CERN Antiproton Decelerator, has recently implemented a novel beamline for low-energy ($\lesssim$ 100 eV) positron and antiproton transport between cylindrical Penning traps that have strong axial magnetic fields. Here, we describe how a combination of semianalytical and numerical calculations were used to optimise the layout and design of this beamline. Using experimental measurements taken during the initial commissioning of the instrument, we evaluate its performance and validate the models used for its development. By combining data from a range of sources, we show that the beamline has a high transfer efficiency, and estimate that the percentage of particles captured in the experiments from each bunch is (78 $\pm$ 3)% for up to $10^{5}$ antiprotons, and (71 $\pm$ 5)% for bunches of up to $10^{7}$ positrons., Comment: 15 pages, 15 figures

Published
2022
Full Text
View/download PDF

2. Towards trapped antihydrogen

Author

Jørgensen, L.V., Andresen, G., Bertsche, W., Boston, A., Bowe, P.D., Cesar, C.L., Chapman, S., Charlton, M., Fajans, J., Fujiwara, M.C., Funakoshi, R., Gill, D.R., Hangst, J.S., Hayano, R.S., Hydomako, R., Jenkins, M.J., Kurchaninov, L., Madsen, N., Nolan, P., Olchanski, K., Olin, A., Page, R.D., Povilus, A., Robicheaux, F., Sarid, E., Silveira, D.M., Storey, J.W., Thompson, R.I., van der Werf, D.P., Wurtele, J.S., and Yamazaki, Y.

Published
2008
Full Text
View/download PDF

3. Antihydrogen physics at ALPHA/CERN

Author

Cesar, C.L., Andresen, G.B., Bertsche, W., Bowe, P.D., Bray, C.C., Butler, E., Chapman, S., Charlton, M., Fajans, J., Fujiwara, M.C., Funakoshi, R., Gill, D.R., Hangst, J.S., Hardy, W.N., Hayano, R.S., Hayden, M.E., Humphries, A.J., Hydomako, R., Jenkins, M.J., Jorgensen, L.V., Kurchaninov, L., Lambo, R., Madsen, N., Nolan, P., Olchanski, K., Olin, A., Page, R.D., Povilus, A., Pusa, P., Robicheaux, F., Sarid, E., Nasr, S. Seif El, Silveira, D.M., Storey, J.W., Thompson, R.I., van der Werf, D.P., Wurtele, J.S., and Yamazaki, Y.

Subjects
Atomic spectroscopy -- Methods, Antimatter -- Atomic properties, Physics, Atomic properties, Research, Methods
Abstract

Cold antihydrogen has been produced at CERN (Amoretti et al. (Nature, 419, 456 (2002)), Gabrielse et al. (Phys. Rev. Lett. 89, 213401 (2002))), with the aim of performing a high-precision spectroscopic comparison with hydrogen as a test of the CPT symmetry. Hydrogen, a unique system used for the development of quantum mechanics and quantum electrodynamics, has been continuously used to produce high-precision tests of theories and measurements of fundamental constants and can lead to a very sensitive search for CPT violation. After the initial production of cold antihydrogen atoms by the ATHENA group, the ALPHA Collaboration (http://alpha.web.cem.ch/) has set forth on an experiment to trap and perform high-resolution laser spectroscopy on the 1S-2S transition of both atoms. In this contribution, we will review the motivations, goals, techniques, and recent developments towards this fundamental physics test. We present new discussion on predicted lineshapes for the 1S-2S spectroscopy of trapped atoms in a regime not discussed before. PACS Nos: 36.10.-k, 32.60.+i, 37.10.Gh Nous avons produit de l'anti-hydrogene an CERN (Amoretti et al. (Nature, 419, 456 (2002)), Gabrielse et al. (Phys. Rev. Lett. 89, 213401 (2002))), pour faire des comparaisons spectroscopiques de haute precision avec ''hydrogene dans le cadre d'un test de la symetrie CPT. L'hydrogene, qui a joue un role unique dans le developpement de la mecanique quantique et de 1'electrodynamique quantique, a ete utilise continuellement dans des tests de haute precision des theories et des mesures des constantes fondamentales et pent nous conduire a une recherche tres precise de la violation CPT. Apres que le groupe ATHENA ait produit 'anti-hydrogene froid, l'equipe ALPHA (http://alpha.web.cern.ch/) a developpe un montage pour pieger les deux types d' atome et faire des mesures de spectroscopie laser de haute precision des transitions 1S-2S dans les deux types d'atomes. Nous passons ici en revue les motivations, les buts, les techniques et les developpements recents de ce test fondamental en physique. Nous presentons de nouvelles idees sur la forme des lignes en spectroscopie 1S-2S pour des atomes pieges dans un regime qui n'a pas encore ete discute. [Traduit par la Redaction], I Introduction The very fundamental discrete symmetry of CPT, standing for the simultaneous operations of charge conjugation (C), parity inversion (P), and time reversal (T), is a base for quantum [...]

Published
2009
Full Text
View/download PDF

4. A magnetic trap for antihydrogen confinement

Author

Bertsche, W., Boston, A., Bowe, P.D., Cesar, C.L., Chapman, S., Charlton, M., Chartier, M., Deutsch, A., Fajans, J., Fujiwara, M.C., Funakoshi, R., Gomberoff, K., Hangst, J.S., Hayano, R.S., Jenkins, M.J., Jørgensen, L.V., Ko, P., Madsen, N., Nolan, P., Page, R.D., Posada, L.G.C., Povilus, A., Sarid, E., Silveira, D.M., van der Werf, D.P., Yamazaki, Y., Parker, B., Escallier, J., and Ghosh, A.

Published
2006
Full Text
View/download PDF

6. Silicon vertex detector upgrade in the ALPHA experiment

Author

Amole, C, Andresen, G.B, Ashkezari, M.D, Baquero-Ruiz, M, Bertsche, W, Burrows, C, Butler, E, Capra, A, 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, Isaac, C.A, Jonsell, S, Kurchaninov, L, Little, A, Madsen, N, McKenna, J.T.K, Menary, S, Napoli, S.C, Nolan, P, Olchanski, K, Olin, A, Povilus, A, Pusa, P, Rasmussen, C.Ø, Robicheaux, F, Sacramento, R.L, Sampson, J.A, Sarid, E, Seddon, D, Silveira, D.M, So, C, Stracka, S, Tharp, T, Thompson, R.I, Thornhill, J, Tooley, M.P, Van Der Werf, D.P, and Wells, D

Subjects
Antimatter, Event reconstruction, Physics::Instrumentation and Detectors, Physics::Accelerator Physics, Physics::Atomic Physics, Silicon Vertex Detector, Detectors and Experimental Techniques, Antihydrogen, Cosmic ray background suppression
Abstract

The Silicon Vertex Detector (SVD) is the main diagnostic tool in the ALPHA-experiment. It provides precise spatial and timing information of antiproton (antihydrogen) annihilation events (vertices), and most importantly, the SVD is capable of directly identifying and analysing single annihilation events, thereby forming the basis of ALPHA's analysis. This paper describes the ALPHA SVD and its upgrade, installed in the ALPHA's new neutral atom trap.

Published
2013

7. Search for trapped antihydrogen in ALPHA

Author

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

Subjects
Condensed Matter::Quantum Gases, Physics::Atomic and Molecular Clusters, Physics::Atomic Physics
Abstract

Antihydrogen spectroscopy promises precise tests of the symmetry of matter and antimatter, and can possibly offer new insights into the baryon asymmetry of the universe. Antihydrogen is, however, difficult to synthesize and is produced only in small quantities. The ALPHA collaboration is therefore pursuing a path towards trapping cold antihydrogen to permit the use of precision atomic physics tools to carry out comparisons of antihydrogen and hydrogen. ALPHA has addressed these challenges. Control of the plasma sizes has helped to lower the influence of the multipole field used in the neutral atom trap, and thus lowered the temperature of the created atoms. Finally, the first systematic attempt to identify trapped antihydrogen in our system is discussed. This discussion includes special techniques for fast release of the trapped anti-atoms, as well as a silicon vertex detector to identify antiproton annihilations. The silicon detector reduces the background of annihilations, including background from antiprotons that can be mirror trapped in the fields of the neutral atom trap. A description of how to differentiate between these events and those resulting from trapped antihydrogen atoms is also included.

Published
2011

8. Antiparticle sources for antihydrogen production and trapping

Author

Charlton, M., Bruun Andresen, Gorm, Ashkezari, M. D., Baquero-Ruiz, M., Bertsche, W., Bowe, Paul David, Bray, C.C., Butler, E., Chapman, S., Friesen, T., Fujiwara, M.C., Gill, D.R., Hangst, Jeffrey S., Hardy, W.N., Hayano, R.S., Hayden, M.E., Humphries, A.J., Hydomako, R., Jonsell, S., Jørgensen, L.V., Kerrigan, S.J., Kurchaninov, L., Lambo, R., Madsen, N., Menary, S., Nolan, P., Olchanski, K., Povilus, A., Pusa, P., Robicheaux, F., Sarid, E., Seif El Nasr, S., 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
Physics::General Physics, Physics::Atomic and Molecular Clusters, Physics::Accelerator Physics, High Energy Physics::Experiment, Physics::Atomic Physics
Abstract

Sources of positrons and antiprotons that are currently used for the formationof antihydrogen with low kinetic energies are reviewed, mostly in the context of the ALPHA collaboration and its predecessor ATHENA. The experiments were undertaken at the Antiproton Decelerator facility, which is located at CERN. Operations performed on the clouds of antiparticles to facilitate their mixing to produce antihydrogen are described. These include accumulation, cooling and manipulation. The formation of antihydrogen and some of the characteristics of the anti-atoms that are created are discussed. Prospects for trapping antihydrogen in a magnetic minimum trap, as envisaged by the ALPHA collaboration, are reviewed.

Published
2011

9. Search for trapped antihydrogen

Author

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., Friesen, T., Fujiwara, M.C., Gill, D.R., Hangst, J.S., Hardy, W.N., Hayano, R.S., Hayden, M.E., Humphries, A.J., Hydomako, R., 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, S., Silveira, D.M., So, C., Storey, J.W., Thompson, R.I., van der Werf, D.P., Wilding, D., Wurtele, J.S., and Yamazaki, Y.

Published
2011
Full Text
View/download PDF

10. Antimatter Plasmas in a Multipole Trap for Antihydrogen

Author

Andresen, G., Bertsche, W., Boston, A., Bowe, Paul David, Cesar, C.L., Chapman, S., Charlton, M., Chartier, M., Deutsch, A., Fajans, J., Fujiwara, M.C., Funakoshi, R., Gill, D.R., Gomberoff, K., Hangst, Jeffrey S., Hayano, R.S., Hydomako, R., Jenkins, M.J., Jørgensen, L.V., Kurchaninov, L., Madsen, Niels, Nolan, P., Olchanski, K., Olin, A., Povilus, A., Robicheaux, F., Sarid, E., Silveira, D.M., Storey, J.W., Telle, H.H., Thompson, R.I., van der Werf, D.P., Wurtele, J.S., and Yamazaki, Y.

Published
2007

11. Antihydrogen formation dynamics in a multipolar neutral anti-atom trap

Author

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

Published
2010
Full Text
View/download PDF

12. The ALPHA antihydrogen trapping apparatus

Author

Amole, C., primary, Andresen, G.B., additional, Ashkezari, M.D., additional, Baquero-Ruiz, M., additional, Bertsche, W., additional, Bowe, P.D., additional, Butler, E., additional, Capra, A., additional, Carpenter, P.T., additional, Cesar, C.L., additional, Chapman, S., additional, Charlton, M., additional, Deller, A., additional, Eriksson, S., additional, Escallier, J., additional, Fajans, J., additional, Friesen, T., additional, Fujiwara, M.C., additional, Gill, D.R., additional, Gutierrez, A., additional, Hangst, J.S., additional, Hardy, W.N., additional, Hayano, R.S., additional, Hayden, M.E., additional, Humphries, A.J., additional, Hurt, J.L., additional, Hydomako, R., additional, Isaac, C.A., additional, Jenkins, M.J., additional, Jonsell, S., additional, Jørgensen, L.V., additional, Kerrigan, S.J., additional, Kurchaninov, L., additional, Madsen, N., additional, Marone, A., additional, McKenna, J.T.K., additional, Menary, S., additional, Nolan, P., additional, Olchanski, K., additional, Olin, A., additional, Parker, B., additional, Povilus, A., additional, Pusa, P., additional, Robicheaux, F., additional, Sarid, E., additional, Seddon, D., additional, Seif El Nasr, S., additional, Silveira, D.M., additional, So, C., additional, Storey, J.W., additional, Thompson, R.I., additional, Thornhill, J., additional, Wells, D., additional, van der Werf, D.P., additional, Wurtele, J.S., additional, and Yamazaki, Y., additional

Published
2014
Full Text
View/download PDF

13. Silicon vertex detector upgrade in the ALPHA experiment

Author

Amole, C., primary, Andresen, G.B., additional, Ashkezari, M.D., additional, Baquero-Ruiz, M., additional, Bertsche, W., additional, Burrows, C., additional, Butler, E., additional, Capra, A., additional, Cesar, C.L., additional, Chapman, S., additional, Charlton, M., additional, Deller, A., additional, Eriksson, S., additional, Fajans, J., additional, Friesen, T., additional, Fujiwara, M.C., additional, Gill, D.R., additional, Gutierrez, A., additional, Hangst, J.S., additional, Hardy, W.N., additional, Hayden, M.E., additional, Humphries, A.J., additional, Isaac, C.A., additional, Jonsell, S., additional, Kurchaninov, L., additional, Little, A., additional, Madsen, N., additional, McKenna, J.T.K., additional, Menary, S., additional, Napoli, S.C., additional, Nolan, P., additional, Olchanski, K., additional, Olin, A., additional, Povilus, A., additional, Pusa, P., additional, Rasmussen, C.Ø., additional, Robicheaux, F., additional, Sacramento, R.L., additional, Stracka, S., additional, Sampson, J.A., additional, Sarid, E., additional, Seddon, D., additional, Silveira, D.M., additional, So, C., additional, Thompson, R.I., additional, Tharp, T., additional, Thornhill, J., additional, Tooley, M.P., additional, van der Werf, D.P., additional, and Wells, D., additional

Published
2013
Full Text
View/download PDF

14. Antihydrogen annihilation reconstruction with the ALPHA silicon detector

Author

Andresen, G.B., primary, Ashkezari, M.D., additional, Bertsche, W., additional, Bowe, P.D., additional, Butler, E., additional, Cesar, C.L., additional, Chapman, S., additional, Charlton, M., additional, Deller, A., additional, Eriksson, S., additional, Fajans, J., additional, Friesen, T., additional, Fujiwara, M.C., additional, Gill, D.R., additional, Gutierrez, A., additional, Hangst, J.S., additional, Hardy, W.N., additional, Hayden, M.E., additional, Hayano, R.S., additional, Humphries, A.J., additional, Hydomako, R., additional, Jonsell, S., additional, Jørgensen, L.V., additional, Kurchaninov, L., additional, Madsen, N., additional, Menary, S., additional, Nolan, P., additional, Olchanski, K., additional, Olin, A., additional, Povilus, A., additional, Pusa, P., additional, Sarid, E., additional, Seif el Nasr, S., additional, Silveira, D.M., additional, So, C., additional, Storey, J.W., additional, Thompson, R.I., additional, van der Werf, D.P., additional, and Yamazaki, Y., additional

Published
2012
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results