Precision mass measurements for fundamental studies Tommi Eronen Max-Planck-Institut für Kernphysik Heidelberg, Germany

Outline Penning trap mass spectrometry – Q = m parent – m daughter Masses for CKM unitarity tests... – Superallowed beta decay – Mirror beta decay Masses for neutrino studies.. – Double beta decay – Double electron capture – Tritium Q-value

Penning Trap Mass Spectrometry Cyclotron frequency Penning trap eigenfrequencies INVARIANCE THEOREM SIDEBAND FREQUENCY

TOF-ICR method For nuclei having T 1/2 > 10 ms

A/q doublets! Q-value measurements – Special – mass doublets, e.g. 76 Ge vs 76 Se – cancellation of systematic errors – 10x better accuracy achieved – Typical: q=1e, B=7T, m=100u with precision ->  m = 100 eV Absolute mass measurements –

Q EC values of superallowed beta emitters

Superallowed beta emitters NEED Q-values at 100-eV level Decays of nuclear 0 + → 0 + states, T=1 Pure Fermi decays Simple decay matrix element Characterized with an ft value – f stat. rate function; (f  Q EC 5 ) – t partial half-life t 1/2 /b

Testing the Standard Model Corrected value: Corrections about 1% [Towner and Hardy, Phys. Rev. C 77, (2008)] Cabibbo-Kobayashi-Maskawa quark mixing matrix Quark-mass eigenstates to weak eigenstates Currently 13 transitions contribute

Superallowed beta emitters - Q EC Bold: Contributes to world average value (13) Why so many JYFL points? -Simultaneous production -No chemical selection

Most recent Q EC from JYFLTRAP 10 C, 34 Ar, 38 Ca, (revisited 46 V) T. Eronen et al., Phys. Rev. C 83, (2011)

Ft values The influence of JYFLTRAP Q EC value measurements.

Ft-value error budget Most precise From J.C. Hardy, I.S. Towner, Phys. Rev. C 79, (2009)

Different  C Towner & Hardy, PRC 77, (2008). Satula et al., PRL 106, (2011). Liang et al., PRC 79, (2009).

Standard Model is still ok? Top-row unitarity requirement: Courtesy of J.C. Hardy With H&T corrections

Superallowed outlook Q EC values: 14 O, heavier A > 62 Branching ratios of T=-1 nuclei Half-lives Theoretical corrections (  C ) A > 62

Q EC values of mirror decays

T=1/2 decays Fermi + Gamow- Teller – Need mixing ratio Currently 5 well known decays O. Naviliat-Cuncic and N. Severijns, PRL 102, (2009) Mirror decays

Error contributions

V ud from different sources

Mirror decays – TODO F/GT ratios; LPC-trap, MOTs, WITCH-trap...  R V  theoretical calculations  NS -  C  measurements of heavy isotopes + theory Measurements of t 1/2, BR and Q EC

Precision mass measurements for neutrino physics Double   decay Double electron capture Tritium Q-value for KATRIN spectrometer

Double beta decays Double   decay (  ) and double-electron capture (2EC) – two-neutrino mode (2  ) and (2 2EC) – neutrinoless mode (0  ) and (0 2EC) Observation would prove that is a Majorana particle Conservation of total lepton number breaks Effective Majorana neutrino mass from half-life

double-electron-capture nuclides double-beta-decay nuclides

Penning trap Q-value harvest... SMILETRAP JYFLTRAP SHIPTRAP LEBIT TRIGATRAP Canadian PT ISOLTRAP FSU

Detection of 0  2  is (huge) background 76 Ge – Heidelberg-Moscow claim – GERDA, MAJORANA experiments T 1/2 ≈10 19 y T 1/2 >10 25 y Penning trap mass spectrometry: Energy of the endpoint! Energy of the endpoint!

Heidelberg-Moscow 76 Ge GERDA has some news soon...

Neutrinoless double-electron capture Predicted half-lives very long, > y, not seen yet Resonant enhancement! From Penning trap mass spectrometry! KK, KL, LL,..

0 + to 0 + transitions between nuclear ground states

|M| =3 for 0 + → 0 + T 1/2 (0 + →0 + ) ~ 3  y for |m 2EC |=1 eV multiple-resonance phenomena in 156 Dy S. Eliseev et al., PRC 84, R (2011)

Tritium beta decay: Neutrino with mass: – Endpoint shifted – Spectrum shape changed Current knowledge: Tritium ( 3 H) Q-value

KATRIN experiment

Endpoint of tritium beta spectrum Electron neutrino mass with KATRIN: 10x better - sensitivity 0.2 eV Goal with Penning traps: Improve 1.2 eV → 0.03 eV

T -3 H Q-value measurements THe-trap 2014 (?)

New technique for Penning trap mass spectrometry Phase-Imaging motion detection Measure motion revolutions in the trap – For + and - – Recipe: Excite the motion (dipolar RF E-field) Project to magnetron motion Count revolutions + phase of the last round – Some x10 faster or more precise than TOF-ICR Developed at SHIPTRAP by S. Eliseev et al. (2012->)

position-sensitive detector Penning trap Phase imaging B 2D delay-line MCP

PI-ICR method 36 Eliseev et al., PRL 110, (2013)

37 On the Way to Mass Measurements

Summary Q-values from mass spectrometry for – Testing the Standard Model Superallowed beta decays (some cases left to measure) Mirror decays (plenty of cases still to measure) – Neutrino studies Neutrinoless double beta- decay Neutrinoless double electron capture New mass measurement techniques

Thank you for your attention!