@article {98, title = {SDR, EVC, and SDREVC: Limitations and Extensions}, journal = {Journal of Plasma Physics}, volume = {89}, year = {2023}, pages = {955890501}, doi = {10.1017/S0022377823001022}, author = {Hunter, E.D. and Amsler, C. and Breuker, H. and Bumbar, M. and Chesnevskaya, S. and Costantini, G. and Ferragut, R. and Giammarchi, M. and Gligorova, A. and Gosta, G. and Higaki, H. and Killian, C. and Kraxberger, V. and Kuroda, N. and Lanz, A. and Leali, M. and Maero, G. and Malbrunot, C. and Mascagna, V. and Matsuda, Y. and M{\"a}ckel, V. and Migliorati, S. and Murtagh, D.J. and Nanda, A. and Nowak, L. and Parnefjord Gustafsson, F. and Rheinfrank, S. and Rom{\'e}, M. and Simon, M.C. and Tajima, M. and Toso, V. and Ulmer, S. and Ventrurelli, L. and Weiser, A. and Widmann, E. and Yamazaki, Y. and Zmeskal, J. and The ASACUSA-Cusp Collaboration} } @article {99, title = {Slow positron production and storage for the ASACUSA-Cusp experiment}, journal = {Journal of Plasma Physics}, volume = {89}, year = {2023}, pages = {905890608}, doi = {10.1017/S0022377823001034}, author = {Murtagh, D.J. and Amsler, C. and Breuker, H. and Bumbar, M. and Chesnevskaya, S. and Costantini, G. and Ferragut, R. and Giammarchi, M. and Gligorova, A. and Gosta, G. and Higaki, H. and Hunter, E.D. and Killian, C. and Kraxberger, V. and Kuroda, N. and Lanz, A. and Leali, M. and Maero, G. and Malbrunot, C. and Mascagna, V. and Matsuda, Y. and M{\"a}ckel, V. and Migliorati, S. and Nanda, A. and Nowak, L. and Parnefjord Gustafsson, F. and Rheinfrank, S. and Rom{\'e}, M. and Simon, M.C. and Tajima, M. and Toso, V. and Ulmer, S. and Venturelli, L. and Weiser, A. and Widmann, E. and Wolz, T. and Yamazaki, Y. and Zmeskal, J.} } @article {96, title = {Upgrade of ASACUSA{\textquoteright}s antihydrogen detector}, journal = {Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment}, volume = {1045}, year = {2023}, pages = {167568}, abstract = {The goal of the ASACUSA (Atomic Spectroscopy And Collisions Using Slow Antiprotons) CUSP experiment at CERN{\textquoteright}s Antiproton Decelerator is to measure the ground state hyperfine splitting of antihydrogen in order to test whether CPT invariance is broken. The ASACUSA hodoscope is a detector consisting of two layers of 32 plastic scintillator bars individually read out by two serially connected silicon photomultipliers (SiPMs) on each end. Two additional layers for position resolution along the beam axis were scintillator fibres, which will now be replaced by scintillating tiles placed onto the existing bars and also read out by SiPMs. If the antiproton of antihydrogen annihilates in the centre of the hodoscope, particles (mostly pions) are produced and travel through the various layers of the detector and produce signals. The hodoscope was successfully used during the last data taking period at CERN. The necessary time resolution to discriminate between particles travelling through the detector from outside and particles produced in the centre of the detector was achieved by the use of waveform digitisers and software constant fraction discrimination. The disadvantage of this readout scheme was the slow readout speed, which was improved by two orders of magnitude. This was done by omitting the digitisers and replacing them with TDCs reading out the digital time-over-threshold (ToT) signal using leading edge discrimination.}, keywords = {Antihydrogen, antimatter, Data acquisition, Silicon photomultiplier}, issn = {0168-9002}, doi = {https://doi.org/10.1016/j.nima.2022.167568}, url = {https://www.sciencedirect.com/science/article/pii/S0168900222008609}, author = {V. Kraxberger and C. Amsler and H. Breuker and S. Chesnevskaya and G. Costantini and R. Ferragut and M. Giammarchi and A. Gligorova and G. Gosta and H. Higaki and E.D. Hunter and C. Killian and V. Kletzl and N. Kuroda and A. Lanz and M. Leali and V. M{\"a}ckel and G. Maero and C. Malbrunot and V. Mascagna and Y. Matsuda and S. Migliorati and D.J. Murtagh and Y. Nagata and A. Nanda and L. Nowak and E. Pasino and M. Rom{\'e} and M.C. Simon and M. Tajima and V. Toso and S. Ulmer and L. Venturelli and A. Weiser and E. Widmann and T. Wolz and Y. Yamazaki and J. Zmeskal} } @article {97, title = {Minimizing plasma temperature for antimatter mixing experiments}, journal = {EPJ Web Conf.}, volume = {262}, year = {2022}, pages = {01007}, doi = {10.1051/epjconf/202226201007}, url = {https://doi.org/10.1051/epjconf/202226201007}, author = {Hunter, E.D. and Amsler, C. and Breuker, H. and Chesnevskaya, S. and Costantini, G. and Ferragut, R. and Giammarchi, M. and Gligorova, A. and Gosta, G. and Higaki, H. and Kanai, Y. and Killian, C. and Kletzl, V. and Kraxberger, V. and Kuroda, N. and Lanz, A. and Leali, M. and M{\"a}ckel, V. and Maero, G. and Malbrunot, C. and Mascagna, V. and Matsuda, Y. and Migliorati, S. and Murtagh, D.J. and Nagata, Y. and Nanda, A. and Nowak, L. and Pasino, E. and Rom{\'e}, M. and Simon, M.C. and Tajima, M. and Toso, V. and Ulmer, S. and Uggerh\oj, U. and Venturelli, L. and Weiser, A. and Widmann, E. and Wolz, T. and Yamazaki, Y. and Zmeskal, J. and (The ASACUSA-Cusp Collaboration)} } @article {95, title = {Reducing the background temperature for cyclotron cooling in a cryogenic Penning{\textendash}Malmberg trap}, journal = {Physics of Plasmas}, volume = {29}, year = {2022}, month = {08}, pages = {083303}, abstract = {Magnetized nonneutral plasma composed of electrons or positrons couples to the local microwave environment via cyclotron radiation. The equilibrium plasma temperature depends on the microwave energy density near the cyclotron frequency. Fine copper meshes and cryogenic microwave absorbing material were used to lower the effective temperature of the radiation environment in ASACUSA{\textquoteright}s Cusp trap, resulting in significantly reduced plasma temperature.}, issn = {1070-664X}, doi = {10.1063/5.0093360}, url = {https://doi.org/10.1063/5.0093360}, author = {Amsler, C. and Breuker, H. and Chesnevskaya, S. and Costantini, G. and Ferragut, R. and Giammarchi, M. and Gligorova, A. and Gosta, G. and Higaki, H. and Hunter, E. D. and Killian, C. and Kletzl, V. and Kraxberger, V. and Kuroda, N. and Lanz, A. and Leali, M. and M{\"a}ckel, V. and Maero, G. and Malbrunot, C. and Mascagna, V. and Matsuda, Y. and Migliorati, S. and Murtagh, D. J. and Nagata, Y. and Nanda, A. and Nowak, L. and Pasino, E. and Rom{\'e}, M. and Simon, M. C. and Tajima, M. and Toso, V. and Ulmer, S. and Venturelli, L. and Weiser, A. and Widmann, E. and Wolz, T. and Yamazaki, Y. and Zmeskal, J.} } @article {94, title = {Measurement of the principal quantum number distribution in a beam of antihydrogen atoms}, volume = {75}, year = {2021}, month = {2021/03/08}, pages = {91}, abstract = {The ASACUSA (Atomic Spectroscopy And Collisions Using Slow Antiprotons) collaboration plans to measure the ground-state hyperfine splitting of antihydrogen in a beam at the CERN Antiproton Decelerator with initial relative precision of $$10^{-6}$$or better, to test the fundamental CPT (combination of charge conjugation, parity transformation and time reversal) symmetry between matter and antimatter. This challenging goal requires a polarised antihydrogen beam with a sufficient number of antihydrogen atoms in the ground state. The first measurement of the quantum state distribution of antihydrogen atoms in a low magnetic field environment of a few mT is described. Furthermore, the data-driven machine learning analysis to identify antihydrogen events is discussed.}, isbn = {1434-6079}, url = {https://doi.org/10.1140/epjd/s10053-021-00101-y}, author = {Kolbinger, B. and Amsler, C. and Cuendis, S. Arguedas and Breuker, H. and Capon, A. and Costantini, G. and Dupre, P. and Fleck, M. and Gligorova, A. and Higaki, H. and Kanai, Y. and Kletzl, V. and Kuroda, N. and Lanz, A. and Leali, M. and M{\"a}ckel, V. and Malbrunot, C. and Mascagna, V. and Massiczek, O. and Matsuda, Y. and Murtagh, D. J. and Nagata, Y. and Nanda, A. and Nowak, L. and Radics, B. and Sauerzopf, C. and Simon, M. C. and Tajima, M. and Torii, H. A. and Uggerh{\o}j, U. and Ulmer, S. and Venturelli, L. and Weiser, A. and Wiesinger, M. and Widmann, E. and Wolz, T. and Yamazaki, Y. and Zmeskal, J.} } @article {92, title = {Antiproton beams with low energy spread for antihydrogen production}, journal = {Journal of Instrumentation}, volume = {14}, year = {2019}, month = {05/2019}, pages = {P05009{\textendash}P05009}, abstract = {

A low energy antiproton transport from the ASACUSA{\textquoteright}s antiproton accumulation trap (MUSASHI trap) to the antihydrogen production trap (double cusp trap) is developed. The longitudinal antiproton energy spread after the transport line is 0.23{\textpm}0.02 eV, compared with 15 eV with a previous method used in 2012. This reduction is achieved by an adiabatic transport beamline with several pulse-driven coaxial coils. Antihydrogen atoms are synthesized by directly injecting the antiprotons into a positron plasma, resulting in the higher production rate.

}, doi = {10.1088/1748-0221/14/05/p05009}, url = {https://doi.org/10.1088\%2F1748-0221\%2F14\%2F05\%2Fp05009}, author = {M. Tajima and N. Kuroda and C. Amsler and H. Breuker and C. Evans and M. Fleck and A. Gligorova and H. Higaki and Y. Kanai and B. Kolbinger and A. Lanz and M. Leali and V. M{\"a}ckel and C. Malbrunot and V. Mascagna and Y. Matsuda and D. Murtagh and Y. Nagata and A. Nanda and B. Radics and M. Simon and S. Ulmer and L. Venturelli and E. Widmann and M. Wiesinger and Y. Yamazaki} } @article {91, title = {Hyperfine spectroscopy of hydrogen and antihydrogen in ASACUSA}, journal = {Hyperfine Interactions}, volume = {240}, year = {2018}, month = {Dec}, pages = {5}, abstract = {

The ASACUSA collaboration at the Antiproton Decelerator of CERN aims at a precise measurement of the antihydrogen ground-state hyperfine structure as a test of the fundamental CPT symmetry. A beam of antihydrogen atoms is formed in a CUSP trap, undergoes Rabi-type spectroscopy and is detected downstream in a dedicated antihydrogen detector. In parallel measurements using a polarized hydrogen beam are being performed to commission the spectroscopy apparatus and to perform measurements of parameters of the Standard Model Extension (SME). The current status of antihydrogen spectroscopy is reviewed and progress of ASACUSA is presented.

}, issn = {1572-9540}, doi = {10.1007/s10751-018-1536-9}, url = {https://doi.org/10.1007/s10751-018-1536-9}, author = {Widmann, E. and Amsler, C. and Arguedas Cuendis, S. and Breuker, H. and Diermaier, M. and Dupre, P. and Evans, C. and Fleck, M. and Gligorova, A. and Higaki, H. and Kanai, Y. and Kolbinger, B. and Kuroda, N. and Leali, M. and Leite, A. M. M. and M{\"a}ckel, V. and Malbrunot, C. and Mascagna, V. and Massiczek, O. and Matsuda, Y. and Murtagh, D. J. and Nagata, Y. and Nanda, A. and Phan, D. and Sauerzopf, C. and Simon, M. C. and Tajima, M. and Spitzer, H. and Strube, M. and Ulmer, S. and Venturelli, L. and Wiesinger, M. and Yamazaki, Y. and Zmeskal, J.} } @article {93, title = {Recent Developments from ASACUSA on Antihydrogen Detection}, journal = {EPJ Web of Conferences}, volume = {181}, year = {2018}, pages = {01003}, doi = {10.1051/epjconf/201818101003}, url = {https://doi.org/10.1051/epjconf/201818101003}, author = {Kolbinger, B. and Amsler, C. and Breuker, H. and Diermaier, M. and Dupre, P. and Fleck, M. and Gligorova, A. and Higaki, H. and Kanai, Y. and Kobayashi, T. and Leali, M. and M{\"a}ckel, V. and Malbrunot, C. and Mascagna, V. and Massiczek, O. and Matsuda, Y. and Murtagh, D.J. and Nagata, Y. and Sauerzopf, C. and Simon, M.C. and Tajima, M. and Ulmer, S. and Kuroda, N. and Venturelli, L. and Widmann, E. and Yamazaki, Y. and Zmeskal, J.} } @article {74, title = {Intelligent Front-end Electronics for Silicon photodetectors (IFES)}, journal = {Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment}, volume = {819}, year = {2016}, pages = {163 - 166}, abstract = {Abstract While high channel density can be easily achieved for big experiments using custom made microchips, providing something similar for small and medium size experiments imposes a challenge. Within this work we describe a novel and cost effective solution to operate silicon photodetectors such as silicon photo multipliers (SiPM). The {\.I}FES\} modules provide the bias voltage for the detectors, a leading edge discriminator featuring time over threshold and a differential amplifier, all on one printed circuit board. We demonstrate under realistic conditions that the module is usable for high resolution timing measurements exploiting both charge and time information. Furthermore we show that the modules can be easily used in larger detector arrays. All in all this confirms that the {\.I}FES\} modules are a viable option for a broad range of experiments if cost-effectiveness and small form factor are required.}, keywords = {Silicon photomultiplier}, issn = {0168-9002}, doi = {http://dx.doi.org/10.1016/j.nima.2016.02.098}, url = {http://www.sciencedirect.com/science/article/pii/S0168900216300158}, author = {Clemens Sauerzopf and Lukas Gruber and Ken Suzuki and Johann Zmeskal and Eberhard Widmann} } @article {75, title = {The ASACUSA CUSP: an antihydrogen experiment}, journal = {Hyperfine Interactions}, volume = {235}, year = {2015}, pages = {13{\textendash}20}, abstract = {In order to test CPT symmetry between antihydrogen and its counterpart hydrogen, the ASACUSA collaboration plans to perform high precision microwave spectroscopy of ground-state hyperfine splitting of antihydrogen atom in-flight. We have developed an apparatus ({\textquoteleft}{\textquoteleft}cusp trap{\textquoteright}{\textquoteright}) which consists of a superconducting anti-Helmholtz coil and multiple ring electrodes. For the preparation of slow antiprotons and positrons, Penning-Malmberg type traps were utilized. The spectrometer line was positioned downstream of the cusp trap. At the end of the beamline, an antihydrogen beam detector was located, which comprises an inorganic Bismuth Germanium Oxide (BGO) single-crystal scintillator housed in a vacuum duct and surrounding plastic scintillators. A significant fraction of antihydrogen atoms flowing out the cusp trap were detected.}, issn = {1572-9540}, doi = {10.1007/s10751-015-1205-1}, url = {http://dx.doi.org/10.1007/s10751-015-1205-1}, author = {Kuroda, N. and Ulmer, S. and Murtagh, D. J. and Gorp, S. and Nagata, Y. and Diermaier, M. and Federmann, S. and Leali, M. and Malbrunot, C. and Mascagna, V. and Massiczek, O. and Michishio, K. and Mizutani, T. and Mohri, A. and Nagahama, H. and Ohtsuka, M. and Radics, B. and Sakurai, S. and Sauerzopf, C. and Suzuki, K. and Tajima, M. and Torii, H. A. and Venturelli, L. and W{\"u}nschek, B. and Zmeskal, J. and Zurlo, N. and Higaki, H. and Kanai, Y. and Rizzini, E. Lodi and Nagashima, Y. and Matsuda, Y. and Widmann, E. and Yamazaki, Y.} } @article {70, title = {The ASACUSA Micromegas Tracker: A cylindrical, bulk Micromegas detector for antimatter research}, journal = {Review of Scientific Instruments}, volume = {86}, year = {2015}, abstract = {

The ASACUSA Micromegas Tracker (AMT; ASACUSA: Atomic Spectroscopy and Collisions Using Slow Antiprotons) was designed to be able to reconstruct antiproton-nucleon annihilation vertices in three dimensions. The goal of this device is to study antihydrogen formation processes in the ASACUSA cusp trap, which was designed to synthesise a spin-polarised antihydrogen beam for precise tests of Charge, Parity, and Time (CPT) symmetry invariance. This paper discusses the structure and technical details of an AMT detector built into such an environment, its data acquisition system and the first performance with cosmic rays.

}, doi = {http://dx.doi.org/10.1063/1.4927685}, url = {http://scitation.aip.org/content/aip/journal/rsi/86/8/10.1063/1.4927685}, author = {Radics, B. and Nagata, Y. and Yamazaki, Y. and Ishikawa, S. and Kuroda, N. and Matsuda, Y. and Anfreville, M. and Aune, S. and Boyer, M. and Chateau, F. and Combet, M. and Granelli, R. and Legou, P. and Mandjavidze, I. and Procureur, S. and Riallot, M. and Vallage, B. and Vandenbroucke, M.} } @article {21, title = {Target Structure Induced Suppression of the Ionization Cross Section for Very Low Energy Antiproton-Hydrogen Collisions}, journal = {Physical Review LettersPhys. Rev. Lett.}, volume = {105}, year = {2010}, month = {2010/11/17/}, pages = {213201 -}, url = {http://link.aps.org/doi/10.1103/PhysRevLett.105.213201}, author = {Knudsen, H. and Torii, H. A. and Charlton, M. and Enomoto, Y. and Georgescu, I. and Hunniford, C. A. and Kim, C. H. and Kanai, Y. and Kristiansen, H.-P. E. and Kuroda, N. and Lund, M. D. and McCullough, R. W. and T{\"o}kesi, K. and Uggerh{\o}j, U. I. and Yamazaki, Y.} } @article {27, title = {Antiproton and Electron Plasma Behavior and its Control for Production of Ultraslow Antiproton Beams}, journal = {AIP Conference Proceedings}, volume = {796}, year = {2005}, pages = {321-324}, keywords = {plasma electrostatic waves, proton beams}, doi = {10.1063/1.2130188}, url = {http://link.aip.org/link/?APC/796/321/1}, author = {N. Kuroda and H. A. Torii and M. Shibata and Y. Nagata and D. Barna and M. Hori and A. Mohri and K. Komaki and Y. Yamazaki}, editor = {Dieter Grzonka and Rafa{\l} Czy{\.z}ykiewicz and Walter Oelert and Tomasz Ro{\.z}ek and Peter Winter} }