Progress of antihydrogen beam production with the double cusp trap

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1 1 / 34 Progress of antihydrogen beam production with the double cusp trap Yugo Nagata Department of applied physics, Tokyo University of Agriculture and Technology Atomic Physics Research Unit, RIKEN March 7th, 2016 LEAP2016

2 / 34 Y. Nagata 1,2, P. Dupre 2, S. Van Gorp 2, N. Kuroda 3, C. Malbrunot 4,5, D.J.

Kolbinger 4, M. Leali 7, E. Lodi Rizzini 7, V. Mascagna 7, O. Massiczek 5, T. Matsudate 3, H. A.

Ulmer 8, L. Venturelli 7, E. Widmann 5, Y.

Atomic physics research unit, RIKEN, Wako, Saitama 351-0198, Japan 3 Graduate School of Arts and

23, Switzerland 5 Stefan Meyer Institute for Subatomic Physics, Boltzmanngasse 3,1090 Vienna,

Higashi-Hiroshima, Hiroshima 739-8530 Japan 7 Dipartimento di Ingegneria dell Informazione,

2 2 / 34 Y. Nagata 1,2, P. Dupre 2, S. Van Gorp 2, N. Kuroda 3, C. Malbrunot 4,5, D.J. Murtagh 2, B. Radics 2, C. Sauerzopf 5, M. Tajima 3,2, M. Diermaier 5 C. Kaga 6, B. Kolbinger 4, M. Leali 7, E. Lodi Rizzini 7, V. Mascagna 7, O. Massiczek 5, T. Matsudate 3, H. A. Torii 3, B. Wuenschek 5, J. Zmeskal 5, H. Breuker 4, Y. Kanai 2, H. Higaki 6, Y. Matsuda 3, S. Ulmer 8, L. Venturelli 7, E. Widmann 5, Y. Yamazaki 2, 1 Department of Applied Physics, Tokyo University of Agriculture and Technology 2 Atomic physics research unit, RIKEN, Wako, Saitama , Japan 3 Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro, Tokyo , Japan 4 CERN, CH-1211, Geneva 23, Switzerland 5 Stefan Meyer Institute for Subatomic Physics, Boltzmanngasse 3,1090 Vienna, Austria 6 Graduate School of Advanced Sciences of Matter, Hiroshima University,1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima Japan 7 Dipartimento di Ingegneria dell Informazione, Universit a di Brescia & Istituto Nazionale di Fisica Nucleare, Gruppo Collegato di Brescia, Brescia, Italy 8 Ulmer Initiative Research Unit, RIKEN, Wako, Saitama , Japan

3 3 / 34 Table of contents 1 Introduction Motivation Microwave hyperfine spectroscopy of H in ASACUSA 2 Double cusp magnet Superconducting double cusp magnet 3 H synthesis H synthesis 4 H beams and spectroscopy line H beam detector

4 4 / 34 Table of contents 1 Introduction Motivation Microwave hyperfine spectroscopy of H in ASACUSA 2 Double cusp magnet Superconducting double cusp magnet 3 H synthesis H synthesis 4 H beams and spectroscopy line H beam detector

5 5 / 34 Motivation CPT symmetry CPT is a fundamental discrete symmetry in Standard Model. Phenomena which can not be explained in Standard Model Neutrino oscillation. Dark matter and dark energy. Standard Model must be extended. CPT symmetry is worth testing.

6 6 / 34 CPT test using Antihydrogen and Hydrogen CPT theorem tells matter and antimatter are symmetric. For example, mass, charge and spectroscopic properties. CPT symmetry can be tested by comparing matter and antimatter Spectroscopic properties of Hydrogen are well known in high precision. Our target is antihydrogen.

7 7 / 34 Standard Model Extension (SME) The system of antihydrogen is expressed by Dirac ( iγ µ D µ m e )ψ = 0 where D µ = i µ qa µ

8 8 / 34 Standard Model Extension (SME) Introduce local lorenz and CPT violation factor into Standard Model. Dirac ( iγ µ D µ m e CPT & Lorentz violation a e µγ µ b e µγ 5 γ µ 1 2 He µνσ µν + ic e µνγ µ D ν + id e µνγ 5 γ µ D ν )ψ = 0 where D = i µ qa µ Lorentz violation D. Colladay and V. A. Kostelecky, PRD 55 (1997) R. Bluhm, V. A. Kostelecky and N. Russell, PRL 82 (1999) 2254.

9 Standard Model Extension (SME) Dirac ( iγ µ D µ m e CPT & Lorentz violation a e µγ µ b e µγ 5 γ µ 1 2 He µνσ µν + ic e µνγ µ D ν + id e µνγ 5 γ µ D ν )ψ = 0 Lorentz violation 1S-2S and Hyperfine transitions of H are sensitive to CPT violation. 1S-2S and hyperfine are complementary measurement. Energy levels are affected by these factors. Absolute precision is important. 9 / 34

10 10 / 34 Comparison of hydrogen spectroscopy with K 0 CPT test. 1S-2S Hyperfine m K 0 m K0 Frquency 2466 THz 1.4 GHz GHz (497 MeV/c 2 ) Relative precision Absolute precision 11 Hz 1.0 mhz 72 khz The hyperfine splitting of antihydrogen is sensitive considering the absolute precision. We decided to measure the hyperfine transition of antihydrogen.

11 11 / 34 How to measure the hyperfine frequency? Low field seeking(lfs) state and high field seeking(hfs) state Frequency [GHz] e + p (F, M)=(1, -1) (F, M)=(1, 0) (F, M)=(1, 1) (F, M)=(0, 0) B[T] LFS HFS ϕ = µ B F = ϕ If µ is a constant, F = µ B H atoms can be manipulated by magnetic field gradient.

12 12 / 34 How to measure the hyperfine frequency? Unpolarized beam HFS LFS LFS Beam source Spin polarizer (Magnet) Microwave Cavity Detector Spin state analyzer (Magnet) HFS

13 13 / 34 How to measure the hyperfine frequency? Unpolarized beam HFS LFS LFS Beam source Spin polarizer (Magnet) Microwave Cavity Detector Spin state analyzer (Magnet) Multi-ring electrodes HFS H atoms Magnetic field line Single Cusp trap Anti-Helmholtz coils

14 Beam focusing by single cusp magnet 4.5 Antihydrogen 4 B [T] Beam axis z [m] r [m] r [m] F=µ B F Beam axis z [m] B is harmonic radially. Atomic beam can focus, if v z of atoms are same. Y. Nagata and Y. Yamazaki, New J. Phys. 16 (2014) / 34

15 15 / 34 How to measure the hyperfine frequency? Multi-ring electrodes Ground state polarized H beam Low field seeking states High field seeking states H atoms Single Cusp trap Cavity Sextupole magnet Anti-Helmholtz coils H beam Detector

16 16 / 34 Antihydrogen atomic beam production in 2012 In 2012, we suceeded in producing H atomic beams of 60 H / hour. N. Kuroda, S. Ulmer, D.J. Murtagh, S. Van Gorp, Y. Nagata, et al., Nat. Commun., 5, (2014) Improvement from 2012 to 2016 New superconducting magnet was developed. ASACUSA MicroMEAGS tracker was developed. Antiproton injection method was studied. New H beam detector was developed.

17 17 / 34 Table of contents 1 Introduction Motivation Microwave hyperfine spectroscopy of H in ASACUSA 2 Double cusp magnet Superconducting double cusp magnet 3 H synthesis H synthesis 4 H beams and spectroscopy line H beam detector

18 18 / 34 Microwave hyperfine spectroscopy of H Single Cusp trap Superconducting double cusp magnet (two sets of anti-helmholtz coils) MRE Ground state polarized H beam Low field seeking states High field seeking states H atoms Double Cusp trap Cavity Sextupole magnet H beam Detector

19 Beam focusing by double cusp magnet B [T] 6 Antihydrogen r [m] F=µ B F Beam axis z [m] r [m] Beam axis z [m] B is harmonic radially. Atomic beam can be focused by double cusp magnet. 19 / 34

20 22 / 34 Table of contents 1 Introduction Motivation Microwave hyperfine spectroscopy of H in ASACUSA 2 Double cusp magnet Superconducting double cusp magnet 3 H synthesis H synthesis 4 H beams and spectroscopy line H beam detector

21 Experimental setup 22Na source Positron accumulator e+ H Antihydrogen beam detector MUSASHI trap (antiproton trap) Sextupole magnet Microwave cavity Double cusp trap [m] P from Antiproton decelerator (CERN) 23 / 34

22 Introduction Double cusp magnet H synthesis H beams and spectroscopy line Experimental setup (Double cusp trap) Double cusp magnet ASACUSA micromegas tracker (AMT) p e+ Multi-ring electrodes 24 / 34

4 Experimental setup (ASACUSA Micromegas Tracker, AMT) MicroMEGAS Plastic scintillators MRE MicroMEGAS Plastic scintillators Size: radius =78.5mm, length=400mm radius =88.

23 4 Experimental setup (ASACUSA Micromegas Tracker, AMT) MicroMEGAS Plastic scintillators MRE MicroMEGAS Plastic scintillators Size: radius =78.5mm, length=400mm radius =88.5mm, length=400mm Strips: 288 axial and 448 circumferential Resolution: 250µm MicroMEGAS measures the hit positions of particles in each layer. Charged particle tracks are reconstructed Annihilation points of p or H are determined from those tracks. P-20, B. Radics et al. 25 / 34

24 H synthesis in the double cusp trap Multi-ring electrodes p -100 Voltage [V] -200 e+ Mixing region Field ionization well eV p injection 0 < t < 20 s Magnetic field [T] z [m] [ms] P-18, N. Kuroda et al. Next talk by Tajima-san, P-19, M. Tajima et al. 26 / 34

25 H synthesis in the double cusp trap Voltage [V] p -100 Magnetic field [T] e+ Multi-ring electrodes Field ionization well Mixing region z [m] 150eV p injection 0 < t < 20 s [ms] P-18, N. Kuroda et al. Next talk by Tajima-san, P-19, M. Tajima et al. 27 / 34

26 29 / 34 Table of contents 1 Introduction Motivation Microwave hyperfine spectroscopy of H in ASACUSA 2 Double cusp magnet Superconducting double cusp magnet 3 H synthesis H synthesis 4 H beams and spectroscopy line H beam detector

27 Introduction Double cusp magnet H synthesis H beams and spectroscopy line Experimental setup 22 Na source Antihydrogen beam detector Positron accumulator Sextupole magnet MUSASHI trap Double cusp trap Microwave cavity [m] Field ionizer 30 / 34

28 Introduction Double cusp magnet H synthesis H beams and spectroscopy line Experimental setup 22 Na source Antihydrogen beam detector Positron accumulator Reference experiment is going on using hydrogen atoms for high precision measurement. Talk by M. Diermaier on Thursday. Sextupole magnet MUSASHI trap Double cusp trap Microwave cavity [m] Field ionizer 31 / 34

29 Introduction Double cusp magnet H synthesis H beams and spectroscopy line H beam detector Hodoscope H BGO crystal H beam detector consists of 2D BGO detector and hodoscope. P-23 BGO, Y. Nagata et al. P-24 Hodoscope, B. Kolbinger et al. 32 / 34

30 34 / 34 Summary The double cusp trap was developed and suceeded in producing H atoms. The double cusp magnet increase the LFS H beams than single cusp. AMT was developed. Direct injection method for 20 ev antiprotons are developing (next talk). The H beam detector was developed. We are ready to measure the hyperfine splitting of H atoms.

arxiv: v1 [physics.ins-det] 6 Jun 2016

arxiv: v1 [physics.ins-det] 6 Jun 2016 Hyperfine Interactions manuscript No. (will be inserted by the editor) Towards Measuring the Ground State Hyperfine Splitting of Antihydrogen A Progress Report arxiv:1606.01791v1 [physics.ins-det] 6 Jun