The important message(s) from Lectures 1 & 2. [Periodic table]

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1 The important message(s) from Lectures 1 & 2 [Periodic table]

2 The important message(s) from Lectures 1 & Mn58 3 +, s Mn58 2 +, s (0 + ) Mn s 65 s b 3.8,.. g 810.8, , 459.2, E (0) + Mn s 65 s b 6.1,.. g 1447-, 2227 b 3.8,.. g 810.8, , 459.2, (4) + 65 s b 3.8,.. g 810.8, , 459.2, IT Mn s b 6.1,.. g , , (4) + 65 s b 3.8,.. g 810.8, , 459.2, IT Mn58 (1) s b 6.1,.. g , , E 6.25 E 6.25 E 6.25

3 Lecture III 3.1 Selective Radioactive Ion Beam production 3.2 In-source resonance ionization spectroscopy - ISOL (hot cavity approach) - IGISOL (gas cell approach) 3.3 In-gas jet spectroscopy & CRIS 3.4 Towards the superheavy elements Th (a nuclear clock), muonic systems, EDM... Outlook

4 Development of the nuclear chart 284 isotopes with T 1/2 > 10 9 year

5 + the discovery of radioactivity 80 years ago < : Nobel Prize in Chemistry

+ the advent of nuclear reactors (1942) Reactors: n on U <1940 495 1941 1948 822 -

6 + the advent of nuclear reactors (1942) Reactors: n on U < The Italian navigator has landed in the New World - How were the natives? - Very friendly

7 + early Isotope Separator On-Line (ISOL) isotopes < First Isotope Separator On-Line (ISOL) experiment Niels Bohr Institute 1951 fast n on U: Kr and Rb isotopes

8 + sensitive detection methods Selective detection method: decay <

9 + energy increases and driver beam upgrades Light-ion induced spallation Heavy-ion induced fusion <

10 + thin target and projectile fragmentation shorter lifetimes Projectile and target fragmentation + In-flight separation Currently >3500 nuclei experimentally observed; ~7000 bound nuclei Courtesy: Mark Huyse < J. Erler et al., Nature 486 (2012) 509

11 In summary radioactive isotope production Primary nuclear reaction: Fragmentation: high energy protons/heavy ions Fission: proton, neutron, photoninduced Spallation: high energy protons Fusion: light- and heavy ion induced

12 The Isotope Separation On-Line method extractor High-energy primary beam target ion source mass separation Radioactive atoms kv to experiments projectiles target material neutrals ions Low-energy ion beam Mass selection At 205 At Pb, Bi, Po, Rn, Fr etc

13 Production rate (a.u.) Why is selectivity required? Isotope production for a 1 GeV p beam on a La target. What if we desired a beam of 132 Sn? 132 Cs Sn Z=50 Sn J. Lettry, V. Fedoseev (CERN) Mass separation alone

state e - Thorium Z=90 0 ev http://chemistry.bd.psu.edu/jircitano/periodic4.

14 Energy Element selectivity - the atomic fingerprint IP ~6 ev (5-9 ev) e - Hydrogen Z=1 second excited state λ 3 s I ~10-17 cm 2 Carbon Z=6 first excited state λ 2 Argon Z=18 λ 1 s R ~10-12 cm 2 Tantalum Z=73 ground state e - Thorium Z=90 0 ev The ionization potential (IP) for most elements is ~6-9 ev. We need at least 2, usually 3, optical excitations in UV to visible to ionize.

15 Pulsed tunable solidstate laser system

From the optical table to the ion source ISOL 8000 e - Count rate (ions/s) 6000 4000 2000 Step 3: non-resonant 511 nm P sat = 3.

16 From the optical table to the ion source ISOL 8000 e - Count rate (ions/s) Step 3: non-resonant 511 nm P sat = 3.3(W) kv Towards mass separator λ Power (W) Exit hole SPIG Target (~mg/cm 2 ) λ 2 Count rate (ions/s) Step 2: nm P sat = 10(6) mw Cyclotron beam Power (mw) Filament IGISOL Ar/He from gas purifier Laser beams λ 1 e - Ag Count rate (ions/s) Step 1: nm P sat = 1.7(4) mw Power (mw)

17 Projection: Van der Grinten A worldwide endeavour towards pure RIBs TRILIS ISTF2 GISELE ALIS FURIOS IRIS GALS ISAC/TRIUMF HRIB/ORNL GANIL ALTO - Orsay IGISOL/JYFL PNPI JINR LISOL RILIS SPES RISIKO TRIGA-LIS PALIS KISS CRC LLN ISOLDE/CERN INFN IfP/UMz KCh/UMz RIKEN KISS/KEK Laser type Operation Source type Ti:Sa Dye ON-line OFF-line Hot cavity Gas cell planned Courtesy of S. Rothe (ISOLDE)

18 Resonance ionization spectroscopy (RIS) In a variant to laser ionization for RIB production, the pulsed lasers can be applied for Resonance Ionization Spectroscopy (RIS). The lasers are sent into the ion source and the wavelength of an atomic excitation step is scanned. Ions are mass separated and counted. Po (Z=84) 3 mw 20 mw D. Fink et al., PRX 5 (2015)

The mid-shell (N ~104): Pt to Pb nuclei In lecture 1 we saw the relative contributions to the isotope shifts, which, close to lead (Z = 82) are several GHz, with similar sized HFS. (Pb data) H.

19 The mid-shell (N ~104): Pt to Pb nuclei In lecture 1 we saw the relative contributions to the isotope shifts, which, close to lead (Z = 82) are several GHz, with similar sized HFS. (Pb data) H. De Witte et al., PRL 98 (2007) Sensitivity of optical spectroscopy has allowed the probe of nuclei > 20 isotopes from stability. Huge staggering seen in light Hg isotopes (optical pumping in 1970s). Discovery of shape coexistence Pb measured to 182 Pb (T 1/2 55 ms, 1 atoms/s). Ground state wavefunction essentially spherical.

20 In-source laser spectroscopy Hg??

21 Preliminary data taken on Hg/Au (April/May 2015)

IN-SOURCE (RIS) Selective process Short lifetimes, low yields (<1 ion/s) High detection efficiency Poor resolution (100-1000 < CLS) COLLINEAR High resolution Scanning voltage, not frequency Detect

22 IN-SOURCE (RIS) Selective process Short lifetimes, low yields (<1 ion/s) High detection efficiency Poor resolution ( < CLS) COLLINEAR High resolution Scanning voltage, not frequency Detect photons Beams of some 10 3 ions/s Cu b b 1 + (g.s.) Counts Cu I. Stefanescu et al., PRL 98 (2007) P. Vingerhoets Relative et Frequency al., PRC 82 (2010) (MHz)

23 What is the heaviest element measured with collinear laser spectroscopy? Laser ionization of reactorproduced Pu samples (ng) Collinear spectroscopy: 244,242,240,239 Pu A/q

24 Nuclear physics: knowledge of excited levels In-beam and decay spectroscopy of transfermium nuclei Z=105 R.-D.Herzberg and P.T.Greenlees, Prog. Part. Nuc. Phys. 61, 674 (2008)

25 What about our knowledge of spin/parity? :spin/parity known (without brackets!!) even-even nuclei: 0 + source: NNDC 102No 104Rf 100Fm 94Pu 96Cm 98Cf 92U 90Th 88Ra Piet Van Duppen

and for the magnetic moments? M. Sewtz et al., Phys Rev Lett 90 (2003) 163002 N.J.

26 and for the magnetic moments? M. Sewtz et al., Phys Rev Lett 90 (2003) N.J. Stone, Nuclear Data Services, IAEA (2011) 102No 104Rf 100Fm 94Pu 96Cm 98Cf 92U 90Th 88Ra Piet Van Duppen

27 RADRIS technique GSI)

28 First optical spectrum in nobelium Resonant count rate: 271 in 600 seconds 0.45/s

29 A pioneering experiment at LISOL* ( 214,215 Ac) * 1/5/ ϯ 6/12/2014 Alpha counts in 50 s / 100 s 450 Figures of merit: 400 Resolution ~ 5e-7 (FWHM= 400 MHz) 350 Selectivity ~ Efficiency ~ 0.5% Ac (t 1/2 =170 ms) in gas cell - in gas jet Wavenumbers (cm -1 ) Courtesy of R. Ferrer

Decay-assisted laser spectroscopy Perhaps even more exciting is the possibility to perform decay spectroscopy measurements on laser-separated ground- or isomeric states.

30 Decay-assisted laser spectroscopy Perhaps even more exciting is the possibility to perform decay spectroscopy measurements on laser-separated ground- or isomeric states. CRIS hyperfine structure α-particle spectroscopy Isomeric beam deflected to decay station for alphatagging of hyperfine components K. Lynch et al., PRX 4 (2014)

31 Laser spectroscopy of nobelium at GSI 208 Pb( 48 Ca,2n) 254 No M. Laataioui et al., EPJ D 68 (2014) 71 M. Laataioui et al., Hyp. Int. 227 (2014) 69

32 Beyond nuclear shapes...

33 Direct probing of a nucleus with lasers Nuclear clock Europhys. Lett. 61 (2003) 181 PRL 108 (2012) m Th Gamma ray laser Tkalya, PRL 106 (2011) Qubit: quantum computing 3/2 [631] 5/2 [633] ΔE 7.6 ev τ 25 mins? Evolution of fundamental constants Nuclear Excitation by Electron Transition P&T, Europhys. Lett. 61 (2003) 181 PRC 79 (2009) PRC 79 (2009) Izosimov, J. Nucl. Sci. Tech. Supp. 6 (2008) 1

Best optical clocks reach 10-18 precision Goal to utilize

atomic physics - quantum optics - metrology - detector- and

34 Best optical clocks reach precision Goal to utilize nuclear transition Expertise required in: - nuclear physics - atomic physics - quantum optics - metrology - detector- and laser development COLLABORATION Vienna JYFL Munich Heidelberg PTB MPQ Toptica

35 Two main objectives 1. To identify and characterize the isomeric transition - solve riddle of existence - determine the transition energy to allow laser spectroscopy 2. To implement key elements of a nuclear clock - develop trapping and cooling for 229 Th (+ solid-state approaches) - develop CW and pulsed laser sources for interrogation V. Sonnenschein, IM et al., J. Phys B 45 (2012) C.J. Campbell et al., PRL 106 (2011) C.J. Campbell et al., PRL 108 (2012)

36 Physics beyond Standard Model

43 Proton puzzle

44 Proton puzzle

45 Proton puzzle

46 Back to structure...

REGLIS 3 @ SPIRAL2 DAY 1 PHYSICS 94 Ag: high-spin

coexistence and single-particle behaviour 107-101 Sn:

properties, atomic properties Gas cell MR ToF (m/dm ~

station in-gas-cell ionization l 1,2 l 2 l 1 in-gas-jet

Ferrer NUSTAR Annual Meeting 2015 towards DESIR HELIOS

47 REGLIS SPIRAL2 DAY 1 PHYSICS 94 Ag: high-spin isomerism (J π =21 + ), exotic decay modes 80 Zr: shape coexistence and single-particle behaviour Sn: test shell model predictions VHE (Z~89-102): nuclear properties, atomic properties Gas cell MR ToF (m/dm ~ 10 5 ) MCP from S 3 EVRs Neutralized EVRs Photoions S-shape RFQ diff. pumping RFQ QMF (m/dm ~ 100) buncher bender detector station in-gas-cell ionization l 1,2 l 2 l 1 in-gas-jet ionization R. Ferrer et al., NIMB 317 (2013) 570 R. Ferrer NUSTAR Annual Meeting 2015 towards DESIR KU Leuven gas jet optimization Development of the Low Energy Branch at the MARA vacuum-mode recoil separator, JYFL

48 LaSpec at FAIR Protons to Uranium, 1500 AMeV Today s beam intensities ! Spectrometer experiments Low Energy Branch (LEB) HISPEC DESPEC MATS LASPEC High Energy Branch R3B Production target D. Rodriguez et al., EPJ Special Topics 183 (2010) 1 to the Ring Branch ILIMA EXL ELISE AIC

50 Thank you...

Laser spectroscopy of actinides at the IGISOL facility, JYFL. Iain Moore University of Jyväskylä, Finland

Laser spectroscopy of actinides at the IGISOL facility, JYFL Iain Moore University of Jyväskylä, Finland Outline Motivation for heavy element studies Laser ionization and spectroscopy of plutonium Comparison