Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

1

Beam Properties

• Beam energy. (Terminal voltage, TOF, Wien filter, calibration )

• Energy spread. • Energy stability.• Purity. Example contaminated with

= ?

• Charge state. Important for interpreting integrated charge measurement.

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

2

Beam Properties

•B is measured using Hall or NMR probes.• Fringe effects.• Magnetic constant

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

3

Beam Properties

Resonant Capture

(selected energies with large X-section)

Q + ER = Er

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

4

Beam Properties

Compare SRIM

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

5

Beam Properties

Infinite thickness…???

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

6

Beam Properties

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

7

Beam Properties

Compare SRIM

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

8

Beam Properties

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

9

Beam Properties

Non-resonant Capture

(all energies)

E = E + Q - Eex

• Low Q-value low E • HPGe detector calibrated using standard sources.

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

10

Nuclear Reaction Energetics

Conservation Laws• Charge, Baryon number, total energy, linear momentum, angular momentum, parity, (isospin??) …….

apa X

pY

pb

Y

bQTTcmcm iffi 22

+ve Q-value exoergic reaction. -ve Q-value endoergic reaction.

aYb TQTT +ve Q-value reaction possible if Ta 0. -ve Q-value reaction not possible if Ta 0. (Is Ta > |Q| sufficient?).

Conservation of momentum ……

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

11

• Conservation of momentum.• We usually do not detect Y.Show that:

• The threshold energy (for Ta): (the condition occurs for = 0º).

• +ve Q-value reaction possible if Ta 0.• -ve Q-value reaction possible if Ta > TTh.• Coulomb and other barriers…….!!!• Neutrons vs. charged particles.

bY

aaYYbYabaabab mm

TmmQmmmTmmTmmT

])()[(coscos 2

HW 23HW 23

abY

bYTh mmm

mmQT

Nuclear Reaction Energetics

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

12

Nuclear Reaction Energetics

• The double valued situation occurs between TTh and the upper limit Ta

\.

• Double-valued in a forward cone.

aY

Ya mm

mQT

\

aba

aaYYbY

Tmm

TmmQmmm ])()[(cos max

2

HW 23HW 23 (continued)(continued)

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

13

• Discuss thoroughly the 7Li(p,n) reaction.• During the discussion emphasize on the case when the incident proton beam is 30 keV above the threshold.• Use your computing skills.

Nuclear Reaction Energetics

HW 23HW 23 (continued)(continued)

• Discuss the elasticelastic and inelastic inelastic

scatteringscattering of neutronsneutrons using these relations.

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

14

Nuclear Reaction Energetics

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

15

Nuclear Reaction Energetics

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

16

Nuclear Reaction Energetics

Accelerator Physics, JU, First Semester, 2010-2011 (Saed Dababneh).

17

Nuclear Reaction Energetics