1. Young Researchers Session in IFIN-HH 2016
Horia Hulubei National Institute of Physics and Nuclear Engineering - IFIN HH
Complete angular distribution measurements for the study of 156Gd nucleus
Alina-Nicoleta IONESCU
Young Researchers Session in IFIN-HH 2016

2. Outline 1. The motivation of the 156Gd nucleus study
2. The experimental device
- Q3D magnetic spectrometer
- Focal plane detector
3. Experimental conditions and results
4. Conclusions

3. 1. The motivation of the 156Gd nucleus study
-represents an ideal part for the study of collective motion
- the purpose- to study the 0+ excited states which are poorly understood
- the motivation – the transfer strength to excited 0+ states in even-even Gd nuclei should increase linearly with the boson number
-we used the (p,t) transfer reaction – it helps us to observe the 0+ excited states

4. 2. The experimental device
Q3D magnetic spectrometer
- installed in the Maier-Leibnitz-Laboratory for Nuclear and Particle Physics of LMU Munich and TU Munich
consists of a quadrupole magnet (Q) and three dipole magnets (3D)
- allows the separation of the reaction products
- has an energy resolution of dE/E=2x 10-4
can be rotate to measure
angular distributions

5. 2. The experimental device
Focal plane detector
consists of a chamber filled with 500 mbar isobutane, two proportional detectors and a scintillator
- provides information about the position of the particles
- the scintillator is used to measure the residual energy of the particles

6. 3. Experimental conditions and results
E=23 MeV
The beam current intensity was about 2 mA
The thickness of the target= 50 mg/cm2 - deposited on a carbon foil with a thickness of 4.1 mg/cm2
We performed measurements at three magnetic settings at 8 angles: 5o, 10o, 14o, 17o, 23o, 30o, 35o, 40o
Tritons spectra for the second magnetic
settings

7. 3. Experimental conditions and results
The calibration reaction used
Qvalue= keV
Qvalue= keV
Qvalue= keV
Qvaluedifference= keV
Qvaluedifference= keV

8. 3. Experimental conditions and results
The calibration reaction used
Etrit=f1(Channel)
Fascicul de protoni
Tritoni
156Gd
158Gd

9. 3. Experimental conditions and results
The calibration reaction used
Etrit=f1(Channel)
Eexcit=f2(Etrit)

10. DWBA calculations
- Distorted Wave Born Approximation is the most useful one in direct nuclear reaction theory
- Is used to extract the value of transferred angular momentum
- DWBA calculations were performed using CHUCK3 code
- CHUCK3 is a code which uses optical model parameters

11. 3.Experimental conditions and results
Angular distributions- old data
q (deg.)
ds/dW (mb/sr)
0+ states

12. 3.Experimental conditions and results
Angular distributions- new data

13. 3. Experimental conditions and results
0+ states

14. 4. Conclusions
1. We studied the 156Gd nucleus at an incident energy of 23 MeV
2. The resulted tritons were recorded using a high-resolution detector and Q3D magnetic spectrometer
3. Calibration reaction 154Gd(p,t)152Gd in order to calculate the excitation energies for our reaction
4. States with transferred angular momentum with values between 0 and 4
5. We confirmed the prediction of the model

15. Thank you for your attention!