AARHUS UNIVERSITY 1 HANS FYNBO Aarhus University Denmark 12 C and 3  studied with small accelerators 496 th WE-Heraeus-Seminar Bad Honnef February Introduction to the 3  reaction 3  breakup of the Hoyle state Search for “missing” states in 12 C

AARHUS UNIVERSITY 2 4 He +4 He g.s Be 12 C g.s.0 +

AARHUS UNIVERSITY 3 4 He +4 He g.s Be g.s C 7.27   3

AARHUS UNIVERSITY 4 Q 1 = -92 keV    Q 2 = -287 keV   + 8 Be Hoyle state QuantityValueError(%) Q3Q3 379.4(2)keV1.2  rad /  4.12(11) ×  e+e- /  6.7(6) ×  e+e- 52.0(1.4)  eV 2.7 Crannell 2005  e+e- 59.6(1.5)  eV 2.5 Chernykh 2010  ( 8 Be)/  tot >0.964 Freer 1994  ( 8 Be)/  tot 0.83(5)6 Raduta 2011

AARHUS UNIVERSITY 12 C+ 40 Ca 25MeV/u 5

AARHUS UNIVERSITY 6 arXiv: v1 [nucl-th] 3  -rate at low temperatures 8 Be resonance

AARHUS UNIVERSITY 12 C ≈10.3 (0 + ) g.s  7.27 Haruhiko Morinaga (TUM) J  =2 + E≈9.7 MeV 2 + ? 3  -rate at high temperatures

AARHUS UNIVERSITY Phys. Lett. B Phys. Rev. C36 (1987) 54.. The et al. APJ 1998 Tur et al. APJ 2010 Magkotsios et al. APJs 2010 Magkotsios et al. APJ 2011

AARHUS UNIVERSITY 9 3  breakup of the Hoyle state Search for “missing” states in 12 C

AARHUS UNIVERSITY CMAM, Madrid 3 He+ 11 B d+ 12 C* d MeV 3 He Oliver Kirsebom (now at Triumf)

AARHUS UNIVERSITY events 12 C ≈10 0, g.s

AARHUS UNIVERSITY 12 Limits: Raduta et al. DDE = 7.5±4 % DDE = 9.5±4 % SD = 83±5 % (O. Kirsebom et al. to be submitted)

AARHUS UNIVERSITY 13 3  breakup of the Hoyle state Search for “missing” states in 12 C

AARHUS UNIVERSITY 14 2+?2+? Stellenbosch: Freer et al. (2009): 12 C(p,p´) 12 C Yale : Zimmerman et al. (2011): 12 C(p,p´) 12 C Osaka: Itoh et al. (2011): 12 C( ,  ´) 12 C

AARHUS UNIVERSITY 15 Journal of Physics: Conference Series 202 (2010) Journal of Physics: Conference Series 267 (2011)

AARHUS UNIVERSITY Idea 1 : Remove 3 - state using  -decay Only 0 +, 1 +, and 2 + states

AARHUS UNIVERSITY  12 N/ 12 B Magnetp/d 12 N/ 12 B+X 12 C/ 11 B Direct Kinematics+ISOL 12 N/ 12 B+X 12 N/ 12 B  p/d 12 C/ 11 B Magnets Inverse Kinematics+Separator

AARHUS UNIVERSITY 18 R.Raabe 12 N/ 12 B K. Jungmann H. Wilschut TRI  P separator Solveig Hyldegaard

AARHUS UNIVERSITY C ≈ g.s N Q beta =16.32

AARHUS UNIVERSITY 12 C ≈ g.s B Q beta =13.37

AARHUS UNIVERSITY C. Diget (York) Solveig Hyldegaard 12 N/ 12 B IGISOL Experiment

AARHUS UNIVERSITY C ≈ g.s N Q beta =16.32 Natural parity states

AARHUS UNIVERSITY 12 C ≈ g.s B Q beta =13.37

AARHUS UNIVERSITY PL B678, 459 (2009) PR C80, (2009) PR C80, (2009) PR C81, (2010) S. Hyldegaard, C. Diget

AARHUS UNIVERSITY How to get selectivity between 0 + and 2 + ? × × 2+2+ Only 0 +, 1 +, and 2 + statesOnly 1 +, 2 +, and 3 + states

AARHUS UNIVERSITY “  -delayed”  breakup    C Oliver Kirsebom (Triumf) Martin Alcorta (Argonne)

AARHUS UNIVERSITY 3 He+ 10 B p+ 12 C* p MeV M. Alcorta et al., NIM A 605, 318–325 (2009) CMAM, Madrid 3 He+ 11 B d+ 12 C* d MeV 3 He

AARHUS UNIVERSITY O. S. Kirsebom et al., Phys. Lett. B680, (2009) 1 st case :  -decay of 1 + states (proof-of-principle) 3 He+ 10 B p+ 12 C* p+3  3 He

AARHUS UNIVERSITY 1 st case :  -decay of 1 + states (proof-of-principle) M1  -decay ≈ GT  -decay

AARHUS UNIVERSITY 2 nd case :  -decay of 2 + T=1 state + M1 >> E2  1 +,2 +, 3 + no 0 + ! − E1 decay populate negative parity  1 -,2 -, 3 -

AARHUS UNIVERSITY B(p,  )  400keV van de Graaf in Aarhus.

AARHUS UNIVERSITY 12 C ≈10 0, g.s (2 - )

AARHUS UNIVERSITY C ≈10 0, g.s (2 - ) h 165keV

AARHUS UNIVERSITY C ≈10 0, g.s (2 - ) rd case :  -decay of 2 - T=1 state 40h 350keV

AARHUS UNIVERSITY 35 C. Zemach, Phys Rev. 133 (1964) 1201 : Decay to 3  Fynbo et al. Phys Rev C79 (2009) : Decay to 3 

AARHUS UNIVERSITY MeV MeV 11 B(p,  ) 

AARHUS UNIVERSITY Outlook 5 MV van de Graaf in Aarhus (HV 1965) Upgrade of detector setup Other case where the method can be used? 8 Be 16 O …..

AARHUS UNIVERSITY 38 QuantityValueError(%) Q3Q3 (20)keV1.2  rad /  4.12(11) ×  e+e- /  6.74(62) ×  e+e- 52.0(1.4)  eV 2.7 Crannell 2005  e+e- 59.6(1.5)  eV 2.5 Chernykh  ( 8 Be)/  tot >0.964 Freer 1994  ( 8 Be)/  tot 0.83(5)6 Raduta 2011

AARHUS UNIVERSITY THANK YOU FOR YOUR ATTENTION !

AARHUS UNIVERSITY BONUS MATERIAL…

AARHUS UNIVERSITY Decay channels 4 He +4 He+ 4 He g.s Be+ 4 He 12 C ≈ /2 +  The 1 + states cannot decay via the 8 Be ground state because it would require L=1 and therefore a change in parity Natural parity states

AARHUS UNIVERSITY B(GT) B(M1) 1 +,T=1 B(M1) 2 +,T=1 Data FMD

AARHUS UNIVERSITY 12 C ≈10.3 (0 + ) g.s (2 - )  7.27 p+ 11 B 15.96

AARHUS UNIVERSITY 12 C ≈10.3 (0 + ) g.s (2 - )  7.27 p+ 11 B Experimental Dalitz plots

AARHUS UNIVERSITY 12 C ≈10.3 (0 + ) g.s (2 - )  7.27 p+ 11 B The MeV state 2–2– 4–4– √ X

AARHUS UNIVERSITY 12 C ≈10.3 (0 + ) g.s (2 - )  7.27 p+ 11 B The MeV state 2–2– 2–2– 1) A.A.Korsheninnikov, Sov. J. Nucl. Phys. 52 (1990) 2) H.Fynbo et al., PRL 91 (2003) 3) R.Alvarez-Rodriguez et al., PRL 99 (2007) 1)2) 3)

AARHUS UNIVERSITY 4 He +4 He g.s Be ≈10 0 +,2 +  8 Be s g.s C C*   47

AARHUS UNIVERSITY 12 C *  Be  1 +  2 +  3 E 1 = m 23 /(m 1 +m 23 ) x Q I = 2/3 xQ I 12 C 8 Be  2 +  3 QIQI Q II E1E1 E2E2 E 3 ii 2/3Q I R.H. Dalitz, Philos. Mag. 44, 1068 (1953). Energy conservation Momentum conservation Dalitz plot