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Present status of search for francium EDM. contents. CYRIC Tohoku Univ., Univ. of Tokyo, Tokyo Univ. Agri. Tech., RCNP Osaka Univ., Kyoto Univ., Tohoku Univ., Tokyo Inst. Tech., Kyusyu Univ.,. Introduction CYRIC new ECRIS Swinger magnet Setup Surface Ionizer Beam Transport
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Present status of search for francium EDM contents CYRIC Tohoku Univ., Univ. of Tokyo, Tokyo Univ. Agri. Tech., RCNP Osaka Univ., Kyoto Univ., Tohoku Univ., Tokyo Inst. Tech., Kyusyu Univ., • Introduction • CYRIC • new ECRIS • Swinger magnet • Setup • Surface Ionizer • Beam Transport • Neutralizer • Laser trapping • Research Plan T. Aoki, A. Hatakeyama, K. Hatanaka, Detector Group, CYRIC, Tohoku University Hirokazu Kawamura K. Harada, T. Hayamizu, K. Imai, M. Itoh, H. Kawamura, T. Murakami, A. Oikawa, Y. Sakemi, M. Saito, T. Sato, T. Shimizu, M. Uchida, T. Wakasa, H.P. Yoshida.
EDM search ~ Laser trap Room temp. Liq3He Liq4He BEC FD 1 mK 1 mK 1 K 1000 K 1 nK temperature Laser cooling Evaporation cooling Francium: Laser cooling to a few mK and trapping. → Very long interaction time! Improve measurement precision! High precision measurement in laser cooled/trapped 210Fr E.D. Commins et al, 2002 Laser cooled/trapped atom Atomic beam Laser World record MOT • Heaviest Alkali Atom = 210Fr : Large Enhancement Factor • Cooling & Trapping Long Coherence Time • Precision x 600 ~ Next Generation EDM Search
High Intensity Laser Cooled Francium Factory at CYRIC AVF Cyclotron Primary beam: 100MeV 18O5+ Production: 18O+197Au→210Fr+5n Beam Swinger 18O beam Beam Transport/ Diagnosis System Neutralizer 210Fr atom 209-210Fr product. cross section [mb] 197Au target 100 Zeeman Cooling Surface Ionizer 210Fr+ ion 10 Magneto-Optical Trap Cooled 210Fr 1 70 80 90 100 Beam Energy [MeV]
New ECR Ion Source 10 GHz ECRIS ~ Request: Heavier Nuclide & Higher Energy 2008/July: Move from RIKEN 2009/May: Test start 2009/July: First acceleration 2009/July: Shutdown for Renovation -- 2010/March 2010/June: First Run for Experiment 18O beam New ECRIS: >2euA (next step), Old ECRIS: 100enA Swinger magnet 2010/May: Swinger fixed @ 45 deg. 2010/May– Test Run, Performance Check
Surface Ionizer-I Measured alpha-ray pectrum 197Au target 18O beam 210Fr (6.543MeV) 50-200um thick gold electroplating 206At (5.703MeV) Fr+ ion count on Ni-mount CYRIC group LNL (Italy) Produced 210Fr in Au target Calculation 1.4x107 atom/s 8x106 atom/s 4.1x104 atom/s Measurement Extracted 210Fr 3x106 atom/s 0.29% Extraction efficiency 40% Stancari, NIMA594(2008)321
Surface Ionizer-II Aim for: Fr+ yield > 106pps, Extraction efficiency > 10% (Ionizer-I: ~0.1%) Frion 45 deg incident Swinger magnet 18O beam Rb beam Production: 18O+197Au→210Fr+5n Surface ionizer • 18O beam 45 deg. Incident • Prevent gold from flowing out. • Vertical Fr extraction from Au target • Yield increase. • SiC heater + target cooler • maintain temperature • (oven 1500 deg C, target 1000 deg C) • Port for stable Rb beam • Offline test. Fr ion Einzel lens Extraction electrode Stable Rbbeam Oven (W) 197Au target (1000 deg C) 1mm thick gold plate Target rod (W)
Rb oven (Rb atom beam source) Offline Test TOSCA Simulation Electric field; Finite Element Method • Vacuum test • Heating test • Voltage apply test Surface ionizer-II collimate extraction 18O beam Au target Rb ion beam first observed at viewer on July 6 Surface Ionizer-II
Fr Beam Transport Beam line Overview Ion Optics (UeGios) Requirement High Transport Efficiency (~100%) Focused Beam (φ5mm) @ Neutralizer Extreme High Vacuum : Differential Pumping 10-6to 10-9 Torr Beam Diagnosis/Monitor System
Alignment Laser & Radiation Thermometer Electrode Cable port Alignment Laser SSD Steering Deflection electrode Under construction @ KT Science Ltd. To be installed in August 2010.
Q-electrode Electrostatic Quadrupole Triplets TOSCA(FEM) XZ YZ • After Baking (130V), • Simple Vacuum Test • We achieved 10-9 Torr ! ~ 1 week SiO2 duct Reduce outgas from electrodes
Neutralizer Which has a higher neutralization efficiency? Y ~ EWF(3.1eV) < EIP(4.1eV) → Fr atom @ many laboratories! • Yttrium catcher • Charge exchange with Alkali vapor • Ion-Electron Recombination Li+ + Na Li + Na+ @ TRIUMF-ISAC Fr+ + Rb Fr + Rb+ @ SUNY Focused beam high efficiency Low energy laser cooling Ultrahigh vacuum laser trapping Fr+ + e- Fr + hν ~ 700 mm Fr+ion~ keV Fratom Zeeman slower, MOT chamber. Deceleration ~ eV Focus e-gun Laser Focus
e-gun type Neutralizer TOSCA(FEM) Neutralizer Very low recombination cross section? Need to make energy very low? Rb beam test is currently in progress in Japan! Offline setup
Laser lab. F=3 267 MHz F=15/2 F=2 52P3/2 617 MHz 157 MHz F=13/2 F=1 F=0 72 MHz 72P3/2 500 MHz F=11/2 F= 9/2 397 MHz 780 nm Cooling 795 nm F=13/2 Repumping 72P1/2 6149 MHz F=11/2 Cooling COHERENT Repumping Verdi + MBR110(Ti:S Laser) 718 nm 817 nm to be installed in July/23 F=2 F=13/2 718nm 52S1/2 6.834 GHz 72S1/2 F=1 46.768 GHz 87Rb F=11/2 210Fr ECLD + Taper amp. 780nm
Neutron Flight Path Cooled Francium Beamline Laser lab. Q-electrode Fr+ ion Neutralizer Zeeman slower MOT chamber Optical fiber (150m) MOT • Renovation Clean room • Design … Zeeman slower, MOT chamber
Research Plan 2010/July Online test -- Surface Ionizer + Beam Transport + Neutralizer 2010High-intensity Fr-ion beam 2011High-intensity neutral Fr atom + MOT -- Complete Laser-Cooled Francium Facility 2012Start EDM measurement 2013Establish precision EDM measurement -- Aim for World Record Fr+ extraction yield: 106 cps Fr0 trap: 106 atoms de < 10-28e cm
setup 18O5+Beam Triplet-Q 241Am (for SSD source test) Extraction electrode 460mm SSD Fr+ Fr+ Fr+ Fr+ Fr+ Fr+ 874mm 197Au Surface ionizer Experimental setup for surface ionizer-I Primary beam line Surface ionizer SSD holder SSD:detect alpha particle from Fr on its surface. @CYRICcourse-34 Beam transport system
Surface ionizer-II / Heating test Shroud Cathode
For Ultrahigh Vacuum of Beam Transport System Surface Ionizer Neutralizer 10-5 Calculation of Vacuum 10-6 TMP 10-7 Pressure [Torr] TMP 400L/s *3 10-8 TMP 10-9 Q-electrode Heating Test 200 150 100 Temperature [deg. C] 50 900mm 0
to Trap 18O beam Fr atom Frion Au target Y target Surface Ionizer Neutralizer Yttrium catcher neutralizer • Target : Gold (Au) ~ EWF(5.1eV)>EIP(4.1eV) → Fr+ ion • Target : Yttrium (Y) ~ EWF(3.1eV)<EIP(4.1eV) → Fr atom • Oven (Y) temperature : 1000 K ~ heater temperature for Fr atom release • Capturing velocity of MOT : Vc~1 m/s • Fraction of trapping atoms : 10-4 ~ 10-5 • High trapping efficiency realization ~ need to cool atoms Heating (~1000K) vFr~281 m/s, vrms~345 m/s Fr ion Fr atom vRb~333 m/s , vrms~408 m/s Y target Neutralized Fr atom is diffused. 20
Ionization Oxygen Ar Recombination Ionization/Recombination constant Omegatron (user) has succeeded in the neutralization of Ar (O). 1eV 1keV 1eV 1keV Ne Na (Alkali metal) (rare gas) 1keV 1eV 1eV 1keV
http://www.omegatron.co.jp Application of deceleration-type slow-neutral beam generator to thin-film (Nitride or Oxidize film) production Ion accel. 1000eV VDS ~80eV anode O2 target Electron bombard type Discharge chamber Extract. electrode Neutralizer 2nd focus lens Decel. lens 1st focus lens 1012 atoms/sec Equivalent energy ~ 20-30eV Atoms soft-landing on target thin-film produced target Valid gas … O, N, Ar and rare gas Heating holder
Rb+ energy 5keV | 0eV | 1keV | 10keV | Cs+-Cs Rb+-Rb TRIUMF-ISAC Neutralization using Alkali vapor Fr+-Rb Na vapor density ~ 1014 atom/cm2 Neutralization efficiency ~ 95% Vacuum pressure ~ 2x10-7 Torr (= 3x10-5 Pa) Rb+-Cs 8Li energy ~ 30keV Cs+-Rb SUNY (Sprouse) Rb vapor density ~ 5x1013 atom/cm3 Perel,Phys.Rev.138(1965)A937 Neutralization efficiency >80% 210Fr energy ~ 5keV
TA EDLD Grating Trap Laser LD Sr cooling/trap system Laser transport Laser room : non-radiation controlled area Laser for Rb Laser for Fr Laser for Sr Fr cooling/MOT/ Laser Trap Sr cooling/MOT Optical fiber (~150m) TOF tunnel Neutral Fr atom MOT Laser cooling Laser Trap “Science trap” Next generation EDM search: … Fr-Sr Ultraslow polar molecule at Feshbach resonance