Transfer reactions with Transfer reactions with 88LiLi

(a status report)(a status report)

PhD student: Elisabeth TengbornPhD student: Elisabeth TengbornSupervisor: Thomas NilssonSupervisor: Thomas Nilsson

Subatomic physics, Chalmers University of TechnologySubatomic physics, Chalmers University of Technology

Scientific motivationScientific motivation

Structure of neutron-rich lithium isotopes through a set of Structure of neutron-rich lithium isotopes through a set of experimentsexperiments

isotopic chain with the last bound two-neutron halo nucleus isotopic chain with the last bound two-neutron halo nucleus 1111LiLi Transfer reactions in inverse kinematics allows us to Transfer reactions in inverse kinematics allows us to

obtain the angular distribution → obtain the angular distribution → ll value of the populated state value of the populated state How large part of the wave function for the populated state can How large part of the wave function for the populated state can

be described as a single particle state be described as a single particle state Made possible thanks to REX-ISOLDEMade possible thanks to REX-ISOLDE Compare with theoretical models: Compare with theoretical models:

ab-initioab-initio shell modelshell modelthrough the spectroscopic factorsthrough the spectroscopic factors

Scientific motivationScientific motivation

22H(H(99Li,t)Li,t)88Li Li (Jeppesen et al. Phys. Lett. B 635 (2006) 17-22)(Jeppesen et al. Phys. Lett. B 635 (2006) 17-22) Discrepancy in spectroscopic Discrepancy in spectroscopic factors on an absolute scalefactors on an absolute scale

Benchmarking experiment Benchmarking experiment Reaction channels:Reaction channels: 22H(H(88Li,p)Li,p)99LiLi(*)(*) (one neutron pick-up – (d,p)) (one neutron pick-up – (d,p))

22H(H(88Li,d)Li,d)88LiLi(*)(*) ( ((in)(in)elastic scattering – (d,d))elastic scattering – (d,d)) 22H(H(88Li,t)Li,t)77LiLi(*)(*) (well known nucleus – (d,t)) (well known nucleus – (d,t))

REX-ISOLDE@ISOLDE, CERNREX-ISOLDE@ISOLDE, CERN

Experimental set-up Experimental set-up

8Li3+

9Li*

p

REX-ISOLDE

E detector

E detector

ΔE detector –DSSSD1

ΔE detector –DSSSD2

ΔE + E detector = telescope detector

Monitordetector

Intensityreduction

foil

DSSSD1 & 2 have 32 front & 32 backstrips → thus being position sensitive

Energy levels of Energy levels of 99Li:Li: g. s. (3/2-)g. s. (3/2-) 2.691 MeV (1/2-)2.691 MeV (1/2-) 4.296 MeV (5/2-)4.296 MeV (5/2-) 5.38 MeV5.38 MeV

Energy levels of Energy levels of 88Li:Li:g. s. (2+)g. s. (2+)0.9808 MeV (1+)0.9808 MeV (1+)2.255 MeV (3+)2.255 MeV (3+)3.21 MeV (1+)3.21 MeV (1+)

Energy levels of Energy levels of 77Li:Li:g. s. (3/2-) g. s. (3/2-) 0.47761 MeV (1/2-)0.47761 MeV (1/2-)4.652 MeV (7/2-)4.652 MeV (7/2-)6.604 MeV (5/2-)6.604 MeV (5/2-)

Data from TUNL

Energy vs. angle distributionsEnergy vs. angle distributions

8Li + 2H → 9Li* + p8Li + 2H → 9Li* + p

The kinematical curves overlaid represent feeding to the known low-lying states in 9Li. In each The curves correspond to reactions in the beginning and in the end of the target.

ExcitationExcitationenergy energy curvescurves

Eex(9Li) Eex(7Li)

Eex(8Li)

0.47761 MeV0.47761 MeV4.652 MeV4.652 MeV6.604 MeV6.604 MeV7.454 MeV7.454 MeV

2.691 MeV2.691 MeV4.296 MeV4.296 MeV5.38 MeV5.38 MeV

0.9808 MeV0.9808 MeV2.255 MeV2.255 MeV3.21 MeV3.21 MeV

Angular distribution, absolute scaleAngular distribution, absolute scale

Ground state for 9Li

dσ/d

Ω [

mb/

sr]

Θcm [degrees]

To DoTo Do

Compare the different reaction channels Compare the different reaction channels with theoretical calculations (DWBA with theoretical calculations (DWBA calculations).calculations).

And now the oxygen is probably gone… so thank you for your attention!