In this work a characterization study of forward emission from a thin, meso-structured silica positron/positronium (Ps) converter following implantation of positrons in light of possible antihydrogen production is presented. The target consisted of a $1 lm thick ultraporous silica film e-gun evaporated onto a 20nm carbon foil. The Ps formation and emission was studied via Single Shot Positron Annihilation Lifetime Spectroscopy measurements after implantation of pulses with 3 4 107 positrons and 10 ns temporal width. The forward emission of implanted positrons and secondary electrons was investigated with a micro-channel plate – phosphor screen assembly, connected either to a CCD camera for imaging of the impinging particles, or to a fast photomultiplier tube to extract information about their time of flight. The maximum Ps formation fraction was estimated to be $10%. At least 10% of the posi- trons implanted with an energy of 3.3 keV are forward-emitted with a scattering angle smaller than 50 and maximum kinetic energy of 1.2 keV. At least 0.1–0.2 secondary electrons per implanted positron were also found to be forward-emitted with a kinetic energy of a few eV. The possible application of this kind of positron/positronium converter for antihydrogen production is discussed.

Characterization of a transmission positron/positronium converter for antihydrogen production

CACCIA, MASSIMO LUGI MARIA;SANTORO, ROMUALDO;
2017-01-01

Abstract

In this work a characterization study of forward emission from a thin, meso-structured silica positron/positronium (Ps) converter following implantation of positrons in light of possible antihydrogen production is presented. The target consisted of a $1 lm thick ultraporous silica film e-gun evaporated onto a 20nm carbon foil. The Ps formation and emission was studied via Single Shot Positron Annihilation Lifetime Spectroscopy measurements after implantation of pulses with 3 4 107 positrons and 10 ns temporal width. The forward emission of implanted positrons and secondary electrons was investigated with a micro-channel plate – phosphor screen assembly, connected either to a CCD camera for imaging of the impinging particles, or to a fast photomultiplier tube to extract information about their time of flight. The maximum Ps formation fraction was estimated to be $10%. At least 10% of the posi- trons implanted with an energy of 3.3 keV are forward-emitted with a scattering angle smaller than 50 and maximum kinetic energy of 1.2 keV. At least 0.1–0.2 secondary electrons per implanted positron were also found to be forward-emitted with a kinetic energy of a few eV. The possible application of this kind of positron/positronium converter for antihydrogen production is discussed.
2017
positronium, mesa-structured silica
Aghion, S.; Amsler, C.; Ariga, T.; Bonomi, G.; Brusa, R. S.; Caccia, MASSIMO LUGI MARIA; Caravita, R.; Castelli, F.; Cerchiari, G.; Comparat, D.; Consolati, G.; Demetrio, A.; Di Noto, L.; Doser, M.; Ereditato, A.; Evans, C.; Ferragut, R.; Fesel, J.; Fontana, A.; Gerber, S.; Giammarchi, M.; Gligorova, A.; Guatieri, F.; Haider, S.; Hinterberger, A.; Holmestad, H.; Kellerbauer, A.; Krasnický, D.; Lagomarsino, V.; Lansonneur, P.; Lebrun, P.; Malbrunot, C.; Mariazzi, S.; Matveev, V.; Mazzotta, Z.; Müller, S. R.; Nebbia, G.; Nedelec, P.; Oberthaler, M.; Pacifico, N.; Pagano, D.; Penasa, L.; Petracek, V.; Povolo, L.; Prelz, F.; Prevedelli, M.; Ravelli, L.; Resch, L.; Rienäcker, B.; Robert, J.; Røhne, O. M.; Rotondi, A.; Sacerdoti, M.; Sandaker, H.; Santoro, Romualdo; Scampoli, P.; Simon, M.; Smestad, L.; Sorrentino, F.; Testera, G.; Tietje, I. C.; Widmann, E.; Yzombard, P.; Zimmer, C.; Zmeskal, J.; Zurlo, N.; Andersen, S. L.; Chevallier, J.; Uggerhøj, U. I.; Lyckegaard, F.
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11383/2063159
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