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Nuclear Structure Information for Fundamental Physics a legacy of T.F. using the Q3D with the Tandem.

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Presentation on theme: "Nuclear Structure Information for Fundamental Physics a legacy of T.F. using the Q3D with the Tandem."— Presentation transcript:

1 Nuclear Structure Information for Fundamental Physics a legacy of T.F. using the Q3D with the Tandem

2 Nuclear Structure Information for Fundamental Physics Instruments: Tandem + Q3D Nuclear Astrophysics Nuclear Structure for 0  -decay Atomic Electric Dipole Moment Unitarity of the CKM matrix Neutron mean life

3 Q3D the Tandem Lab and 14MV Tandem polarized ion source the Q3D large solid angle, superb resolution:  E/E ≈ 2 ·10 -4

4 Performance of the Q3D courtesy: Andreas Heusler

5 Nuclear structure for astrophysics for modelling explosive H-burning we need level properties near the proton separation energy S p Parikh et al: Phys. Rev. C (2009) Wrede et al: Phys. Rev. C (2010) Parikh et al: Phys. Rev. C (2010) Parikh et al: Phys. Rev. C (2011) Laird et al: Phys. Rev. Lett. (2013) Parikh et al.: Phys. Lett. B (2014) Fry et al: Phys. Rev. C (2015) Parikh et al: Phys. Rev. C (2015) Q3D

6 States in 19 Ne at the p - threshold Abundance of 18 F in Novae? one unknown is the cross section for: 18 F + p  → 19 Ne* → 15 O +  Assumption: 3/2 + states just above the p-threshold have strong influence But, none of the 3 states is compatible with 3/2 + !!! p – threshold 6410 keV 15° 20° 30° 19 F( 3 He,t) 19 Ne  E = 14keV (FWHM) Angular distributions Q3D Laird et al: Phys. Rev. Lett. (2013)

7 neutron sources for the s-process 17 O 22 Ne ( ,n) 25 Mg and 13 C ( ,n) 16 O n-production 6359 13 C+  n-poison 4143 16 O+n ? ? ? neutron production and destruction depend critically on the resonance energy and width of the states; there exist quite discrepant values! thresholds T. Faestermann, P. Mohr, R. Hertenberger, H.F. Wirth; Phys. Rev. C 92 (2015)

8 neutron sources for the s-process excite states in 17 O with the reaction 19 F(d,  ) 17 O analyze  -particles with the Q3D spectrograph, resolution 15 – 20 keV, 2 spectra, 12 hours total, fit lines with Gauss or Lorentz shape.  threshold state

9 neutron sources for the s-process 17 O poison 4143 16 O+n ? ? ? production 6359 13 C+  stateenergy (keV)width (keV) 1/2 + 6363.4 (3.1)136 (5) 3/2 + 5084.8 (0.9) 88 (3) 3/2 - 4551.4 (0.7) 38 (3) Results: much more precise than previously, allows reanalysis of indirect cross section determinations

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11 Fission barriers in actinide nuclei (r-process) e.g. 231 Pa(d,p) 232 Pa => fission Coincidence fission  Q3D Rotational bands with huge moment of inertia allow to deduce energies of the potential barriers and depths of the wells Csige et al., PR C 85 (2012) Csige et al., Acta Phys. Pol. (2015) Q3D

12 Nuclear structure for 0  decay We studied pairing properties by (p,t) on 100,98 Mo and 102,100 Ru Thomas et al.: Phys. Rev. C (2012) Similarly by (p,d) and (d,p) on 150 Nd and 150 Sm Sharp et al: ongoing Spectroscopy of 150 Pm Bucurescu et al: Phys. Rev. C (2012) 100 Tc 136 Cs 150 Pm 100 Mo 136 Xe 150 Nd 100 Ru 136 Ba 150 Sm Q3D Nuclear structure for 0  decay

13 PRC84(2011) 136 Xe - 136 Baintermediate nucleus 136 Cs previously known: 01000 2000E*[keV] 138 Ba(d,  ) 136 Cs measured october 2014  E=13keV Q3D

14 A Senior Scientist and the MLL Tandem John P. Schiffer: (Argonne Nat. Lab and Univ. of Chicago) Mail of May 20, 2015 I guess it seemed irrational some 40-50 years ago that there were suddenly so many tandems and cyclotrons built for nuclear structure around the world. But it is even more irrational now to see the world heading for literally NO capability in this field. he initiated the programme to investigate spectroscopic factors for 2  -decay

15 Nuclear structure for new physics The lowest exp. limit of an EDM is d( 199 Hg) < 3.1 x 10 -29 e cm to convert this to CP-odd couplings one has to understand the structure of nuclei in the neighbourhood. At the Q3D we study 199 Hg via 198 Hg(d,p) and 200 Hg(d,t) 197 Hg via 198 Hg(d,t) 198 Hg via 198 Hg(d,d‘) 200 Hg via 200 Hg(d,d‘) 201 Hg via 200 Hg(d,p) Q3D

16 Nuclear structure for flavour physics Experiment: (0 + -0 + Fermi decays)  Q  5 T  =0 ≈2  -strength in nuclear decays: weak coupling constant (corrections ≈2%) with precision Nuclear Physics input presently reached best test of Unitarity: The CKM-matrix relates weak eigenstates to mass eigenstates

17 Nuclear Structure for Flavour Physics for the CKM mixing matrix element V ud from Superallowed  -decay (|V ud | = 0.97417 (21)) we need  -decay Q-values and spectroscopic information Masses: Faestermann et al: EPJA 42 (2009) Wrede et al: Phys. Rev. C81 (2010) Nuclear structure for 62 Ga- 62 Ge Leach et al: Phys. Rev. C87 (2013) Leach et al: Phys. Rev. C88 (2013 ) Q3D

18 From Particle Data Group 2014 neutron lifetime (s)

19 Beta-decay of nuclei Experiment:  Q  5 T  = 3 = 1  -strength in nuclear decays: ≈ 3 ≈ 1 for neutron for triton ≈ 10/3 = 0 for 6 He from theory

20 PDG - from Particle Data Group 2014 with g A /g V from neutron

21 g A from nuclei? 6 He has a pure GT-decay: 0 + to 1 + M F = 0M GT 2 = 10/3 · (1-  ) decay energy and half life are well measured, but the matrix element? relies on the tritium  -decay for 3-body force.

22 g A from nuclei? but the tritium half-life (12.4 a) is not so well known because of bound state  -decay  measure tritium  -decay half-life   N = dN  /dt produce a source with N tritium atoms and measure the  -decay rate dN  /dt

23 N the number of tritons with the reaction 13 C(d,t) 12 C we can produce >10 4 tritons per second and collect them in a 10x10 mm 2 spot. We need a detector which can count the number N of implanted tritons and afterwards, well shielded and with good resolution, measures the  -spectrum to deduce dN  /dt.

24 The Q3D spectrograph at the MLL Tandem Q3D worldwide unique and sought for by: Universität Köln Universität Heidelberg HMI Berlin Technische Universität Darmstadt Univ. Birmingham, UK Univ. Manchester, UK Univ. York, UK Univ. Edinburgh, UK Univ. Catalunya, Barcelona, Spain IPN Orsay, France NIPNE, Bukarest, Romania Univ. Milano, Italy ATOMKI, Debrecen, Hungary Univ. Guelph, Canada McMaster Univ., Hamilton, Canada Triumf, Vancouver, Canada Univ. Washington, Seattle, USA ANL, Argonne, USA MSU, East Lansing, USA Yale Univ., New Haven, USA Univ. Western Cape, South Africa > 40 years old now an endangered species the local group: H.-F. Wirth R. Hertenberger T. Faestermann large solid angle, superb resolution:  E/E ≈ 2 ·10 -4

25 and what do we need? moderate funds for maintenance a scientist, who coordinates the projects a technician, who keeps things running T.F. * 1946 Elise * 16.12.2013 too old! too young!


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