June 3-4, 2013 HIGS2 WS 1

Photodisintegration of the Triton:

A Probe of the Neutron-Neutron Interaction Triangle Universities Nuclear Laboratory (TUNL)

NC Central University

M.W. AhmedB.J. Crowe IIID.M. Markoff

Jagellonian University

H. Witala

C.R. Howell

A.S. Crowell

L.C. Cumberbatch

B. Fallin

F. Friesen

W. Tornow

June 3-4, 2013 HIGS2 WS 2

Measurement of 1S0 nn-Scattering Length

2

2

222

4

0

)21(

4

nnnn

nns

nnnns

a

a

k

krka

nn¼s¾ t

=0

= ¼ s

055.018

5.022

2

1

a

aa

a

NN¼s¾ t

June 3-4, 2013 HIGS2 WS 3

1. Highly sensitive to the nn potential strength

The neutron-neutron 1S0 Scattering Length

10.0005.0

nn

nn

nn

nn

a

a

V

V

2. Limits CSBNpp

NnnCSB aaa

fma

MeVmmIHI

CSB

duem

4.02.1

401

- mixing

G. A. Miller, B. M. K. Nefkens, and I. Slaus, Phys. Rep. 194, 1 (1990)

H. Witala and W. Glockle, PRC 83, 034004 (2011).

CD Bonn (=1.0)ann = -18.8 fmreff = 2.82 fm

June 3-4, 2013 HIGS2 WS 4

Determinations of the 1S0 ann Using - + d n + n +

- + d n + n + ann = -18.5 ± 0.4 ± 0.3 fm C.R. Howell et al., Phys. Lett. B 444, 252 (1998)

ann = -18.6 ± 0.4 ± 0.3 fm Q. Chen et al., Phys. Rev. C 77, 054002 (2008)

ann = -18.6 ± 0.4 ± 0.3 fm B. Gabioud et al., Phys. Lett. B 103, 9 (1981)

ann = -18.7 ± 0.6 ± 0.3 fm O. Schori et al., Phys. Rev. C 35, 2252 (1987)

Average: ann = -18.6 ± 0.3 ± 0.3 fm fmaN

nn 3.03.09.18 (corrected for MMI)

fmfmfmaaa Npp

NnnCSB 5.06.13.179.18

Investigation of reducing theoretical errorA. Gardestig and D.R. Phillips, Phys. Rev. C 73, 014002 (2006)

Constrains value of ann with EFT:J. Kirscher and D.R. Phillips, arXiv;nucl-th, 1106.3171v1

June 3-4, 2013 HIGS2 WS 5

Results from Kinematically Complete nd Breakup Measurements

ann| = 2.5 ± 0.8 fm3 SD difference

nd breakup: nn QFSfrom: H. Witała and W. Glöckle, Phys. Rev. C 83, 034004 (2011)

June 3-4, 2013 HIGS2 WS 6

nn QFS cross section at En=26 MeV Data: measured at Univ. BonnA. Siepe et al., Phys. Rev. C 65, 034010 (2002). Calculations: CD-Bonn NN potential

nn QFS cross section at En=25 MeV Data: measured at CIAEX.C. Ruan et al., Phys. Rev. C 75, 057001 (2007). Calculations: CD-Bonn NN potential

June 3-4, 2013 HIGS2 WS 7

nn interaction strength and dineutron bindingfrom: H. Witała and W. Glöckle, Phys. Rev. C 83, 034004 (2011)

June 3-4, 2013 HIGS2 WS 8

The total cross section for three-body photodisintegration of 3H. This figure is taken from the thesis of R. Skibinski. The data are from Faul et al, Phys. Rev. C 24, 849 (1981). . The calculations are by R. Skibinski The MECs are treated using the Siegert theorem.

3H 3-body photodisintegration3H + p + n + n

June 3-4, 2013 HIGS2 WS 9

Photodisintegration of 3H

June 3-4, 2013 HIGS2 WS 10

3H gas targets

-ray beam

silicon detectors

wire chambers

80 cm

Experiment setup for 3H photodisintegration