subatomic physics at ifa - aarhus universitet · subatomic physics at ifa from an experimentalist...

Subatomic physics at IFA

From an experimentalist point of view.

Jacob G. JohansenAarhus University

October 31th 2012

The world of a subatomic physicist

Isotopes:

300 stable

7000 bound

3000 discovered

Describing the structure of all nuclei (QCD).

Most theories developed from stable nuclei.

Interesting effects occur with large P-N discrepancy.

J. Johansen (AU) Subatomic physic October 31th 2012 2 / 15

Astrophysics

Hans Fynbo in the search of


Astrophysics

Nuclear chart:

After Big bangZ

N


Astrophysics

Nuclear chart:

After Big bang Today

Z

N

→


The triple α-process

Triple α-process:

τ8Be = 0.12 fs

11B + p → 12C → 3α.

Which states are populated?

What are the decay channels?

γ-decay3α

α+8Be.


The local facilities

400keV accelerator:

5MeV accelerator:

11B + p → 12C → 3α.

Kasper Lind Laursen

Morten Lund

Silicon detectors:


The rp-process

The rp-process:1H or 4He capture

β-decay

Waiting points

Interesting nuclei:31Ar → 30S

Gunvor Koldste20Mg → 20Na

Morten Lund


Producing exotic nuclei requires exotic places

Jyväskylä

Gröningen

Genevé

Vancouver

Darmstadt

Dubna


An example of an experiment at CERN11Be + 2H


Beryllium isotopes

The neutron rich Beryllium isotopes:


Transfer reactions starting with 11Be

p n

11Be(1/2+)



〈12Be; 0+| = α 〈10Be; 0+| 〈2n, 1s21/2

| + β 〈10Be; 0+| 〈2n, 0p21/2

| + γ 〈10Be; 0+| 〈2n, 0d25/2

|

p n

11Be(1/2+)

p n

d(11Be,p)12Be



〈12Be; 0+| = α 〈10Be; 0+| 〈2n, 1s21/2

| + β 〈10Be; 0+| 〈2n, 0p21/2

| + γ 〈10Be; 0+| 〈2n, 0d25/2

|

p n

11Be(1/2+)

p n

d(11Be,p)12Be

p n

d(11Be,t)10Be



〈12Be; 0+| = α 〈10Be; 0+| 〈2n, 1s21/2

| + β 〈10Be; 0+| 〈2n, 0p21/2

| + γ 〈10Be; 0+| 〈2n, 0d25/2

|

p n

d(11Be,d’)11Be

p n

d(11Be,p)12Be

p n

d(11Be,t)10Be


How?

CERN:


How?

CERN: ISOLDE:


How?

CERN: ISOLDE: The setup:


The analysis

12Be:

E*-2 -1 0 1 2 3 4

N

0

200

400

600

800

1000

1200

1400

1600

11Be:

E*-2 -1.5 -1 -0.5 0 0.5 1 1.5

N

0

1000

2000

3000

4000

5000

10Be:

E*-2 -1 0 1 2 3 4 5 6 7

N

0

100

200

300

400

500

600

700

800


The analysis

12Be:

E*-2 -1 0 1 2 3 4

N

0

200

400

600

800

1000

1200

1400

1600

E0 0.5 1 1.5 2 2.5 3

N

0

500

1000

1500

2000

2500

11Be:

E*-2 -1.5 -1 -0.5 0 0.5 1 1.5 2

N0

1000

2000

3000

4000

5000

E0 0.2 0.4 0.6 0.8 1 1.2

N

0

500

1000

1500

2000

2500

3000

3500

10Be:

E*-2 -1 0 1 2 3 4 5 6 7

N

0

100

200

300

400

500

600

700

800

E0 1 2 3 4 5 6 7 8

N

0

100

200

300

400

500

600

700

800

Triton_EGammaEntries 70170Mean 1.409RMS 1.309


Crossing a barrier never ment to be crossed

12Be: 11Be: 10Be:

0 30 60 90 120 150 180t

1

10

x

A

0 30 60 90 120 150 180t

1

10

x

B

0 30 60 90 120 150 180t

0.1

1

10

x

C

0 30 60 90 120 150 180t

1

10

x

D

0 30 60 90 120 150 180t

10

100x

0 30 60 90 120 150 180t

1

10

x

A

0 30 60 90 120 150 180t

1

10

x

B

0 30 60 90 120 150 180t

1

10

x

C

0 30 60 90 120 150 180t

1

10

x

D

0 30 60 90 120 150 180t

1

10

x

E

0 30 60 90 120 150 180t

1

10

x

F


Summary and advert

We are trying to understand the structure of all isotopes

Nuclear physic is applied in medical physic and astrophysics.

We are trying to reproduce the reactions in laboratory

InhouseAt large accelerator facilities around the world

Examples on nuclei we study: 12C, 31Ar, 30S, 20Mg, 20Na and10,11,12Be.

Exotic nuclei are produced by fragmentation.


Summary and advert

We are trying to understand the structure of all isotopes

Nuclear physic is applied in medical physic and astrophysics.

We are trying to reproduce the reactions in laboratory

InhouseAt large accelerator facilities around the world

Examples on nuclei we study: 12C, 31Ar, 30S, 20Mg, 20Na and10,11,12Be.

Exotic nuclei are produced by fragmentation.

Thank you

More info on 10,11,12Be at my PhD-defence, December 7th


subatomic physics at ifa - aarhus universitet · subatomic physics at ifa from an experimentalist...

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