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Addendum to Proposal P-242 to the INTC. SEARCH FOR NEW CANDIDATES FOR THE NEUTRINO-ORIENTED PRECISION MASS SPECTROMETRY. Spokesperson : Sergey Eliseev Max-Planck Institut für Kernphysik, Heidelberg, Germany. D. Beck, K. Blaum , M. Block, Ch . Böhm, Ch . Borgmann, M. Breitenfeldt ,
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Addendum to Proposal P-242 to the INTC SEARCH FOR NEW CANDIDATES FOR THE NEUTRINO-ORIENTED PRECISION MASS SPECTROMETRY Spokesperson: Sergey Eliseev Max-Planck Institut für Kernphysik, Heidelberg, Germany 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 MPIK-GSI-Mainz-Leuven-CERN-MSU-FAIR-Orsay-RIKEN-PNPI-Greifswald-Dresden
Recentlimitofm(νe) ≈2 eVisobtainedfromthe analysisofthe end pointofb--decay status on antineutrino mass mn=0 mn=2 eV Q mn the smaller the Q-value the higher the sensitivity 3H (Q=18.6 keV) 187Re (Q=2.57 keV) 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 Chet al 2005 Eur. Phys. J. C 40 447
status on neutrino mass The mostrecentlimitofm(νe) ≈200 eVisobtainedfromtheanalysisof de-excitationspectrumofelectroncapture(EC) in 163Ho B-binding energy of captured electron mn QEC the smaller the QEC-B the higher the sensitivity There are a lot ofpotentially suitable candidates !!! but the choice of the suitable ones is hampered by poor knowledge of their Q-values De Rujula A et al 1982 Phys. Lett. B 118429 Springer P T et al 1987 Phys. Rev. A 35 679
194Hg and 202Pb also are very promising nuclides !!! 163Ho is by far the best candidate QEC-B≈ 0.5 keV PROPOSAL P-242 (2008) “A determination of the Q-values of EC in 194Hg &202Pb by direct Penning trap mass measurements of 194Hg/Au and 202Pb/Tl “ status on neutrino mass potential candidates
status of proposal ISOLTRAP beam times scheduled for IS473 Masses of three out of four nuclides have been measured !!! 194Hg/Au and 202Pb The Q-value of EC in 194Hg has been determined !!!
QEC – BL1 = (15 ± 4) keV → It is possible to improve the upper limit on neutrino mass from 200 eV to 20 eV with this nuclide status of proposal AME2003 Q-value of EC in 194Hg is (69±14) keV New Q-value of EC in 194Hg is (29±4) keV old scheme of EC in 194Hg new scheme of EC in 194Hg ? Eliseev S et al 2010 Phys. Lett. B 693 426
addendum to proposal In order to determine the Q-value of EC in 202Pb, it remains to only measure the mass of 202Tl Addendum to Proposal P-242 “Determination ofthemassof202Tl at ISOLTRAP with an accuracyof 2 keV“
Beam time request * The number of shifts requested is based on the experience acquired during the previous runs