1. Addendum to Proposal P-242 to the INTC SEARCH FOR NEW CANDIDATES FOR THE NEUTRINO-ORIENTED PRECISION MASS SPECTROMETRY D. Beck, K. Blaum, M. Block, Ch. Böhm, Ch. Borgmann, M. Breitenfeldt, S. Eliseev, V. Fedoseev, S. George, F. Herfurth, A. Herlert, H.-J. Kluge, M. Kowalska, S. Kreim, D. Lunney, V. Manea, S. Naimi, D. Neidherr, Yu. N. Novikov, M. Rosenbusch, S. Schwarz, L. Schweikhard, M. Seliverstov, A. Sokolov, J. Stanja, F. Wienholtz, R. N. Wolf, K. Zuber Spokesperson : Sergey Eliseev Max-Planck Institut für Kernphysik, Heidelberg, Germany MPIK-GSI-Mainz-Leuven-CERN-MSU-FAIR-Orsay-RIKEN-PNPI-Greifswald-Dresden

2. m =0 m =2 eV Q m status on antineutrino mass the smaller the Q-value the higher the sensitivity 3 H (Q=18.6 keV) 187 Re (Q=2.57 keV) Recent limit of m(ν e ) ≈ 2 eV is obtained from the analysis of the end point of  - -decay There are only two suitable candidates Limited number of suitable nuclides is a substantial restriction for future experiments! Lobashev V M et al 1999 Phys. Lett. B 460 227 Kraus Ch et al 2005 Eur. Phys. J. C 40 447

3. Q EC m status on neutrino mass the smaller the Q EC -B the higher the sensitivity The most recent limit of m(ν e ) ≈ 200 eV is obtained from the analysis of de-excitation spectrum of electron capture (EC) in 163 Ho There are a lot of potentially suitable candidates !!! but the choice of the suitable ones is hampered by poor knowledge of their Q-values B-binding energy of captured electron De Rujula A et al 1982 Phys. Lett. B 118 429 Springer P T et al 1987 Phys. Rev. A 35 679

4. status on neutrino mass 163 Ho is by far the best candidate Q EC -B ≈ 0.5 keV Q EC -B ≈ 0.5 keV potential candidates 194 Hg and 202 Pb also are very promising nuclides !!! PROPOSAL P-242 (2008) “A determination of the Q-values of EC in 194 Hg & 202 Pb by direct Penning trap mass measurements of 194 Hg/Au and 202 Pb/Tl “

5. status of proposal ISOLTRAP beam times scheduled for IS473 Beam timeDedicated forTarget/ion sourceRemark May 2008 202 Pb, 202 TlUC x /Hot plasmacanceled due to power failure July 2008 194 Au UC x /RILIS successful August 2008 194 Hg UC x /Hot plasmaby-product of experiment IS461; successful October 2008 202 Pb UC x /Hot plasmaby-product of IS463; successful April 2009 194 HgUC x /Hot plasmaunsuccessful; no 194 Hg was seen June 2011 202 Pb 202 Tl UC x /RILIS UC x /Surface ionization direct measurement of the Q EC -value. The Q EC -value is measured with insufficient accuracy Masses of three out of four nuclides have been measured !!! 194 Hg/Au and 202 Pb 194 Hg/Au and 202 Pb The Q-value of EC in 194 Hg has been determined !!!

6. status of proposal AME2003 Q-value of EC in 194 Hg is (69±14) keV New Q-value of EC in 194 Hg is (29±4) keV old scheme of EC in 194 Hg new scheme of EC in 194 Hg ? Q EC – B L1 = (15 ± 4) keV Q EC – B L1 = (15 ± 4) keV → It is possible to improve the upper limit on neutrino mass from 200 eV to 20 eV with this nuclide Eliseev S et al 2010 Phys. Lett. B 693 426

7. addendum to proposal In order to determine the Q-value of EC in 202 Pb, it remains to only measure the mass of 202 Tl Addendum to Proposal P-242 “Determination of the mass of 202 Tl at ISOLTRAP with an accuracy of 2 keV“

8. Beam time request NuclideIon SourceTarget Expected yield, ions/  C Reference masses№ of Shifts 202 TlRILISUC x 1·10 5 (RILIS) 133 Cs5*5* * The number of shifts requested is based on the experience acquired during the previous runs