Search

Your search keyword '"Jonsell, S"' showing total 22 results
Start Over Author "Jonsell, S" Database OpenAIRE
22 results on '"Jonsell, S"'

1. Production of antihydrogen atoms by 6 keV antiprotons through a positronium cloud

Author

Adrich, P, Blumer, P, Caratsch, G, Chung, M, Cladé, P, Comini, P, Crivelli, P, Dalkarov, O, Debu, P, Douillet, A, Drapier, D, Froelich, P, Garroum, N, Guellati-Khelifa, S, Guyomard, J, Hervieux, P-A, Hilico, L, Indelicato, P, Jonsell, S, Karr, J-P, Kim, B, Kim, S, Kim, E-S, Ko, Y.J, Kosinski, T, Kuroda, N, Latacz, B.M, Lee, B, Lee, H, Lee, J, Lim, E, Liszkay, L, Lunney, D, Manfredi, G, Mansoulié, B, Matusiak, M, Nesvizhevsky, V, Nez, F, Niang, S, Ohayon, B, Park, K, Paul, N, Pérez, P, Regenfus, C, Reynaud, S, Roumegou, C, Roussé, J-Y, Sacquin, Y, Sadowski, G, Sarkisyan, J, Sato, M, Schmidt-Kaler, F, Staszczak, M, Szymczyk, K, Tanaka, T.A, Tuchming, B, Vallage, B, Voronin, A, van der Werf, D.P, Won, D, Wronka, S, Yamazaki, Y, Yoo, K-H, Yzombard, P, Laboratoire Kastler Brossel (LKB [Collège de France]), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Collège de France (CdF (institution))-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Université d'Évry-Val-d'Essonne (UEVE), Conservatoire National des Arts et Métiers [CNAM] (CNAM), HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Institut Laue-Langevin (ILL)

Subjects
antihydrogen, production, CERN Lab, Physics - Instrumentation and Detectors, background, anti-p, beam, positron, beam, atom, FOS: Physical sciences, Instrumentation and Detectors (physics.ins-det), antihydrogen, beam, charge exchange, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), positronium, target, electron, linear accelerator, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], cloud, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det]
Abstract

International audience; We report on the first production of an antihydrogen beam by charge exchange of 6.1 keV antiprotons with a cloud of positronium in the GBAR experiment at CERN. The antiproton beam was delivered by the AD/ELENA facility. The positronium target was produced from a positron beam itself obtained from an electron linear accelerator. We observe an excess over background indicating antihydrogen production with a significance of 3-4 standard deviations.

Published
2023

2. AD-7/GBAR status report for the 2023 CERN SPSC

Author

Lunney, D, Roumegou, C, Blumer, P, Caratsch, G, Crivelli, P, Ohayon, B, Regenfus, C, Sarkisyan, J, Nesvizhevsky, V, Sacquin, Y, Vallage, B, Liszkay, L, Debu, P, Comini, P, Roussé, J-Y, Tuchming, B, Mansoulié, B, Niang, S, Pérez, P, Sadowski, G, Schmidt-Kaler, F, Indelicato, P, Drapier, D, Guellati, S, Hilico, L, Cladé, P, Douillet, A, Karr, J-P, Nez, F, Yzombard, P, Paul, N, Reynaud, S, van der Werf, DP, Jonsell, S, Froelich, P, Kim, B, Kim, S, Lee, B, Lee, H, Park, K, Won, D, Lee, J, Ko, Y, Kim, E-S, Lim, E, Chung, M, Yoo, K-H, Hervieux, P-A, Manfredi, G, Yamazaki, Y, Kuroda, N, Tanaka, T, Sato, M, Kosinski, T, Matusiak, M, Staszczak, M, Wronka, S, Adrich, P, and Szymczyk, K

Subjects
Detectors and Experimental Techniques
Abstract

We report on the activities performed during 2022 and the plans for 2023 for the GBAR experiment.

Published
2023

3. Investigation of the fine structure of antihydrogen

Author

Ahmadi, M, Alves, BXR, Baker, CJ, Bertsche, W, Capra, A, Carruth, C, Cesar, CL, Charlton, M, Cohen, S, Collister, R, Eriksson, S, Evans, A, Evetts, N, Fajans, J, Friesen, T, Fujiwara, MC, Gill, DR, Granum, P, Hangst, JS, Hardy, WN, Hayden, ME, Hunter, ED, Isaac, CA, Johnson, MA, Jones, JM, Jones, SA, Jonsell, S, Khramov, A, Knapp, P, Kurchaninov, L, Madsen, N, Maxwell, D, McKenna, JTK, Menary, S, Michan, JM, Momose, T, Munich, JJ, Olchanski, K, Olin, A, Pusa, P, Rasmussen, CO, Robicheaux, F, Sacramento, RL, Sameed, M, Sarid, E, Silveira, DM, So, C, Starko, DM, Stutter, G, Tharp, TD, Thompson, RI, van der Werf, DP, Wurtele, JS, Collaboration, ALPHA, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and ALPHA

Subjects
Physics::General Physics, experimental methods, p: charge distribution, magnetic field, size, 01 natural sciences, Article, spectrum, Standard Model, symbols.namesake, p: size, Quantum mechanics, 0103 physical sciences, quantum electrodynamics, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Physics::Atomic Physics, 010306 general physics, Antihydrogen, Quantum, fine structure, Physics, antihydrogen, Multidisciplinary, Zeeman effect, 010308 nuclear & particles physics, precision measurement, Charge (physics), 3. Good health, Lamb shift, asymmetry: CPT, Automatic Keywords, Antiproton, hydrogen, Antimatter, frequency, symbols, Exotic atoms and molecules, Experimental particle physics, Particle Physics - Experiment, experimental results
Abstract

At the historic Shelter Island Conference on the Foundations of Quantum Mechanics in 1947, Willis Lamb reported an unexpected feature in the fine structure of atomic hydrogen: a separation of the 2S1/2 and 2P1/2 states1. The observation of this separation, now known as the Lamb shift, marked an important event in the evolution of modern physics, inspiring others to develop the theory of quantum electrodynamics2–5. Quantum electrodynamics also describes antimatter, but it has only recently become possible to synthesize and trap atomic antimatter to probe its structure. Mirroring the historical development of quantum atomic physics in the twentieth century, modern measurements on anti-atoms represent a unique approach for testing quantum electrodynamics and the foundational symmetries of the standard model. Here we report measurements of the fine structure in the n = 2 states of antihydrogen, the antimatter counterpart of the hydrogen atom. Using optical excitation of the 1S–2P Lyman-α transitions in antihydrogen6, we determine their frequencies in a magnetic field of 1 tesla to a precision of 16 parts per billion. Assuming the standard Zeeman and hyperfine interactions, we infer the zero-field fine-structure splitting (2P1/2–2P3/2) in antihydrogen. The resulting value is consistent with the predictions of quantum electrodynamics to a precision of 2 per cent. Using our previously measured value of the 1S–2S transition frequency6,7, we find that the classic Lamb shift in antihydrogen (2S1/2–2P1/2 splitting at zero field) is consistent with theory at a level of 11 per cent. Our observations represent an important step towards precision measurements of the fine structure and the Lamb shift in the antihydrogen spectrum as tests of the charge–parity–time symmetry8 and towards the determination of other fundamental quantities, such as the antiproton charge radius9,10, in this antimatter system., Precision measurements of the 1S–2P transition in antihydrogen that take into account the standard Zeeman and hyperfine effects confirm the predictions of quantum electrodynamics.

Published
2020

4. Machine learning for antihydrogen detection at ALPHA

Author

Capra, A, Ahmadi, M, Alves, BXR, Baker, CJ, Bertsche, WA, Butler, E, Carruth, C, Cesar, CL, Charlton, M, Cohen, S, Collister, RA, Eriksson, S, Evans, A, Evetts, NA, Fajans, J, Friesen, T, Fujiwara, MC, Gill, DR, Gutierrez, A, Hangst, JS, Hardy, WN, Hayden, ME, Isaac, CA, Ishida, A, Johnson, MA, Jones, SA, Jonsell, S, Kurchaninov, L, Madsen, N, Mathers, MR, Maxwell, D, McKenna, JTK, Menary, S, Michan, JM, Momose, T, Munich, JJ, Nolan, P, Olchanski, K, Olin, A, Pusa, P, Rasmussen, CO, Robicheaux, F, Sacramento, RL, Sameed, M, Sarid, E, Silveira, DM, Stracka, S, So, C, Stutter, G, Tharp, TD, Thompson, JE, Thompson, RI, van der Werf, DP, Wurtele, JS, IOP, and Collaboration, ALPHA

Subjects
Physics, History, Particle physics, 010308 nuclear & particles physics, 0103 physical sciences, Alpha (ethology), 010306 general physics, Antihydrogen, 01 natural sciences, Computer Science Applications, Education, Computing and Computers
Abstract

The ALPHA experiment at CERN is designed to produce and trap antihydrogen to the purpose of making a precise comparison with hydrogen. The basic technique consists of driving an antihydrogen resonance which will cause the antiatom to leave the trap and annihilate. The main background to antihydrogen detection is due to cosmic rays. When an experimental cycle extends for several minutes, while the number of trapped antihydrogen remains fixed, background rejection can become challenging. Machine learning methods have been employed in ALPHA for several years, leading to a dramatic reduction of the background contamination. This allowed ALPHA to perform the first laser spectroscopy experiment on antihydrogen.

Published
2018

5. Measurements of Properties of Antihydrogen

Author

Olin, Art, Ahmadi, M, Alves, BXR, Baker, CJ, Bertsche, W, Butler, E, Capra, A, Carruth, C, Charman, AE, Evans, LT, Cesar, CL, Charlton, M, Cohen, S, Collister, R, Eriksson, S, Evans, A, Evetts, N, Fajans, J, Friesen, T, Fujiwara, MC, Gill, DR, Hangst, JS, Hardy, WN, Hayden, ME, Isaac, CA, Johnson, MA, Jones, JM, Jones, SA, Jonsell, S, Khramov, A, Knapp, P, Kurchaninov, L, Madsen, N, Maxwell, D, McKenna, JTK, Menary, S, Momose, T, Munich, JJ, Olchanski, K, Olin, A, Pusa, P, Rasmussen, C, Robicheaux, F, Sacramento, RL, Sameed, M, Sarid, E, Silveira, DM, Stutter, G, So, C, Tharp, TD, Thompson, RI, van der Werf, DP, Wurtele, JS, Zhmoginov, AI, and Collaboration, ALPHA

Subjects
Nuclear physics, Physics, Physics::General Physics, Antimatter, Physics::Atomic and Molecular Clusters, Physics::Atomic Physics, Antihydrogen
Abstract

The ALPHA project at the CERN AD is testing fundamental symmetries between matter and antimatter using trapped antihydrogen atoms. The spectrum of the antihydrogen atom may be compared to ordinary hydrogen where it has been measured very precisely. CPT conservation, which underpins our current theoretical framework, requires equality of the masses and charges of matter and its antimatter partners, so antihydrogen spectroscopy presents a path to precision CPT tests. I will discuss the techniques used by ALPHA to trap more than 8000 antihydrogen atoms in 2016, and interrogate them for 600s. The 1S-2S transition in antihydrogen has been observed for the first time, and it agrees with its hydrogen counterpart within an uncertainty of 400 kHz or 0.2 ppb. The charge of the antihydrogen atom has been bounded below [Formula: see text]. A value of 1420.4 0.5MHz for the hyperfine splitting has been obtained from observation of the positron spin resonance spectrum.

Published
2018

6. AD-7/GBAR status report for the 2015 CERN SPSC

Author

Banerjee, D, Biraben, F, Brook-Roberge, D, Charlton, M, Cladé, P, Comini, P, Crivelli, P, Dalkarov, O, Debu, P, Douillet, A, Dufour, G, Dupré, P, Eriksson, S, Froelich, P, Grandemange, P, Guellati, S, Guérout, R, Heinrich, J-M, Hervieux, P-A, Hilico, L, Husson, A, Indelicato, P, Jonsell, S, Karr, J-P, Khabarova, K, Kolachevsky, N, Kuroda, N, Lambrecht, A, Leite, A M M, Liszkay, L, Lotrus, P, Lunney, D, Madsen, N, Manfredi, G, Mansoulié, B, Matsuda, Y, Mohri, A, Mortensen, T, Nagashima, Y, Nesvizhevsky, V, Nez, F, Pérez, P, Regenfus, C, Rey, J-M, Reymond, J-M, Roussé, J-Y, Reynaud, S, Rubbia, A, Sacquin, Y, Schmidt-Kaler, F, Sillitoe, N, Staszczak, M, Szabo-Foster, C I, Torii, H, Vallage, B, Valdes, M, van der Werf, D P, Voronin, A, Walz, J, Wolf, S, Wronka, S, and Yamazaki, Y

Subjects
Physics::Accelerator Physics, Physics::Atomic Physics, Detectors and Experimental Techniques
Abstract

The GBAR experiment will use one of the low energy antiproton beam lines from the ELENA ring that is being prepared and scheduled to start operating in 2017. The apparatus is broadly divided into four sections: antiproton deceleration and focussing, positron production and accumulation, antihydrogen cooling and preparation, and detection. In the following, we give updates on the different parts and the status of preparation for installation in the AD hall, referring to the previous report that was submitted in April of 2014

Published
2015

7. AD-7/GBAR status report for the 2014 CERN SPSC

Author

Dupré, P, Grandemange, P, Lunney, D, Manea, V, Badertscher, A, Banerjee, D, Crivelli, P, Curioni, A, Marchionni, A, Rossi, B, Rubbia, A, Nesvizhevsky, V, Hervieux, P-A, Manfredi, G, Brook-Roberge, D, Comini, P, Debu, P, Liszkay, L, Mansoulié, B, Mortensen, T, Pérez, P, Rey, J-M, Reymond, J-M, Sacquin, Y, Vallage, B, Dalkarov, O, Kolachevskiy, N, Khabarova, K, Voronin, A, Biraben, F, Cladé, P, Douillet, A, Dufour, G, Guellati, S, Hilico, L, Indelicato, P, Lambrecht, A, Karr, J-P, Nez, F, Reynaud, S, Tran, V-Q, Schmidt-Kaler, F, Wolf, S, Walz, J, Staszczak, M, Wronka, S, Mohri, A, Yamazaki, Y, Charlton, M, Eriksson, S, Madsen, N, van der Werf, D P, Kuroda, N, Matsuda, Y, Torii, H, Nagashima, Y, Froelich, P, and Jonsell, S

Subjects
Physics::Accelerator Physics, High Energy Physics::Experiment, Detectors and Experimental Techniques, Nuclear Experiment
Abstract

A status report is given on the preparations and tests in view of the AD-7 / GBAR experiment at the future ELENA facility to be constructed at the CERN Antiproton Decelerator.

Published
2014

8. The ALPHA antihydrogen trapping apparatus

Author

Amole, C, Andresen, GB, Ashkezari, MD, Baquero-Ruiz, M, Bertsche, W, Bowe, PD, Butler, E, Capra, A, Carpenter, PT, Cesar, CL, Chapman, S, Charlton, M, Deller, A, Eriksson, S, Escallier, J, Fajans, J, Friesen, T, Fujiwara, MC, Gill, DR, Gutierrez, A, Hangst, JS, Hardy, WN, Hayano, RS, Hayden, ME, Humphries, AJ, Hurt, JL, Hydomako, R, Isaac, CA, Jenkins, MJ, Jonsell, S, Jørgensen, LV, Kerrigan, SJ, Kurchaninov, L, Madsen, N, Marone, A, McKenna, JTK, Menary, S, Nolan, P, Olchanski, K, Olin, A, Parker, B, Povilus, A, Pusa, P, Robicheaux, F, Sarid, E, Seddon, D, Nasr, S Seif El, Silveira, DM, So, C, Storey, JW, Thompson, RI, Thornhill, J, Wells, D, van der Werf, DP, Wurtele, JS, Yamazaki, Y, and Collaboration, ALPHA

Subjects
Condensed Matter::Quantum Gases, Neutral atom trap, Molecular, Antiprotons, Atomic, Nuclear & Particles Physics, Other Physical Sciences, Positrons, Particle and Plasma Physics, Physics::Atomic and Molecular Clusters, Nuclear, Physics::Atomic Physics, Silicon Vertex Detector, Microwaves, Antihydrogen, Astronomical and Space Sciences
Abstract

The ALPHA collaboration, based at CERN, has recently succeeded in confining cold antihydrogen atoms in a magnetic minimum neutral atom trap and has performed the first study of a resonant transition of the anti-atoms. The ALPHA apparatus will be described herein, with emphasis on the structural aspects, diagnostic methods and techniques that have enabled antihydrogen trapping and experimentation to be achieved. © 2013 Elsevier B.V.

Published
2014

9. 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

10. 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

11. 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

12. Towards antihydrogen trapping and spectroscopy at ALPHA:Proceedings of the 5th International Conference on Trapped Charged Particles and Fundamental Physics (TCP 2010

Author

Butler, E., Bruun Andresen, Gorm, Ashkezari, M. D., Baquero-Ruiz, M., Bertsche, W., Bowe, Paul David, Bray, C. C., Cesar, C. L., Chapman, S., Charlton, M., Fajans, J., 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., 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

13. 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

14. 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

15. 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

16. Controllable 3D atomic Brownian motor in an optical lattice

Author

Dion, C. M., Sjolund, P., Petra, S.J.H., Jonsell, S., Nylen, M., Sanchez-Palencia, Laurent, Kastberg, A., Department of Physics [Umeå], Umeå University, laboratoire Charles Fabry de l'Institut d'Optique / Optique atomique, Laboratoire Charles Fabry de l'Institut d'Optique (LCFIO), and Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)

Abstract

conference; actes; International audience

Published
2006

17. Realization of a 3D Brownian motor in a double symmetric potential

Author

Sjolund, P., Petra, S., Sanchez-Palencia, Laurent, Nylen, M., Dion, C. M., Jonsell, S., Kastberg, A., Department of Physics [Umeå], Umeå University, laboratoire Charles Fabry de l'Institut d'Optique / Optique atomique, Laboratoire Charles Fabry de l'Institut d'Optique (LCFIO), and Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)

Subjects
ComputingMethodologies_GENERAL, ComputingMilieux_MISCELLANEOUS
Abstract

conference; poster

Published
2005

18. The few-body problem for trapped bosons with large scattering length

Author

Jonsell, S., Heiselberg, H., and Pethick, C. J.

Subjects
Condensed Matter::Quantum Gases, Condensed Matter (cond-mat), FOS: Physical sciences, Condensed Matter
Abstract

We calculate energy levels of two and three bosons trapped in a harmonic oscillator potential with oscillator length $a_{\mathrm osc}$. The atoms are assumed to interact through a short-range potential with a scattering length $a$, and the short-distance behavior of the three-body wave function is characterized by a parameter $\theta$. For large positive $a/a_{\mathrm osc}$, the energies of states which, in the absence of the trap, correspond to three free atoms approach values independent of $a$ and $\theta$. For other states the $\theta$ dependence of the energy is strong, but the energy is independent of $a$ for $|a/a_{\mathrm osc}|\gg1$., Comment: 4 pages, 3 figures

Published
2002
Full Text
View/download PDF

21. 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.

22. Towards a test of the Weak Equivalence Principle of gravity using anti-hydrogen at CERN

Author

Banerjee, D., Biraben, F., Charlton, M., Clade, P., Comini, P., Crivelli, P., Dalkarov, O., Debu, P., Dodd, L., Douillet, A., Dufour, G., Dupre, P., Eriksson, S., Froelich, P., Grandemange, P., Guellati, S., Guerout, R., Heinrich, M., Hervieux, P. -A, Hilico, L., Husson, A., Indelicato, P., Jonsell, S., Karr, J. -P, Ksenia Khabarova, Kim, S. K., Kim, Y., Kolachevsky, N., Kuroda, N., Lambrecht, A., Leite, A. M. M., Liszkay, L., Lotrus, P., Lunney, D., Madsen, N., Manfredi, G., Mansouli, B., Matsuda, Y., Mohri, A., Mornacchi, G., Nesvizhevsky, V., Nez, F., Perez, P., Regenfus, C., Rey, J. -M, Reymond, J. -M, Rousse, J-Y, Reynaud, S., Rubbia, A., Sacquin, Y., Schmidt-Kaler, F., Sillitoe, N., Staszczak, M., Torii, H., Heinrich, J. M., Vallage, B., Valdes, M., Werf, D. P., Voronin, A., Walz, J., Wolf, S., Wronka, S., Yamazaki, Y., and IEEE

Catalog

Books, media, physical & digital resources
See catalog results