LABORATORY FOR RADIOCHEMISTRY AND ENVIRONMENTAL CHEMISTRY OF THE UNIVERSITY OF

BERN AND THE PAUL SCHERRER INSITUTE

S. Soverna, March 2002

1 Department for Chemistry and Biochemistry, University of Bern, Switzerland2 Paul Scherrer Institute, Villigen, Switzerland

S. Soverna1,2, R. Dressler2, Ch.E. Düllmann1,2, B. Eichler2,

R. Eichler1,2, H.W. Gäggeler1,2, D. Piguet2, A. Türler1,2

LABORATORY FOR RADIOCHEMISTRY AND ENVIRONMENTAL CHEMISTRY OF THE UNIVERSITY OF

BERN AND THE PAUL SCHERRER INSITUTE

S. Soverna, March 2002

112 behaves like a noble gas:

• Very volatile

• Only Van der Waal interactions with metallic surfaces

Literature: K.S. Pitzer, J. Chem. Phys. 63, 1032 (1975)

112 behaves like a noble metal:

• Very volatile

• Interacts like a metal

Literature: B. Eichler, Kernenergie 10, 307, 1976

LABORATORY FOR RADIOCHEMISTRY AND ENVIRONMENTAL CHEMISTRY OF THE UNIVERSITY OF

BERN AND THE PAUL SCHERRER INSITUTE

S. Soverna, March 2002

COLD temperature gradient: +25 °C to -180 °C

48Ca-beam

238U-target

Recoil chamber

He HeThermostats

ryo n- ine etectorryo n- ine etector

2 x 32 PIN diodes

PIN diodes withAuAu surfaces

Oven(850 °C)

SiO2- column with Pt-foil

N2 (liq.)(-196 °C)

PIN diodes withSiO2SiO2 surfaces

(+25 °C)(+25 °C)

LABORATORY FOR RADIOCHEMISTRY AND ENVIRONMENTAL CHEMISTRY OF THE UNIVERSITY OF

BERN AND THE PAUL SCHERRER INSITUTE

S. Soverna, March 2002

LABORATORY FOR RADIOCHEMISTRY AND ENVIRONMENTAL CHEMISTRY OF THE UNIVERSITY OF

BERN AND THE PAUL SCHERRER INSITUTE

S. Soverna, March 2002

LABORATORY FOR RADIOCHEMISTRY AND ENVIRONMENTAL CHEMISTRY OF THE UNIVERSITY OF

BERN AND THE PAUL SCHERRER INSITUTE

S. Soverna, March 2002

COLD temperature gradient: +25 °C to -180 °C

48Ca-beam

238U-target

Recoil chamber

He HeThermostats

ryo n- ine etectorryo n- ine etector

2 x 32 PIN diodes

PIN diodes withAuAu surfaces

Oven(850 °C)

SiO2- column with Pt-foil

N2 (liq.)(-196 °C)

PIN diodes withSiO2SiO2 surfaces

(+25 °C)(+25 °C)

LABORATORY FOR RADIOCHEMISTRY AND ENVIRONMENTAL CHEMISTRY OF THE UNIVERSITY OF

BERN AND THE PAUL SCHERRER INSITUTE

S. Soverna, March 2002

20Ne-beam

168Yb-target

Recoil chamber

He HeThermostat

(0 °C)Oven(850 °C)

SiO2- column with Pt-foil

N2 (liq.)(-196 °C)

PIN diodes withSiO2SiO2 surfaces AuAu( -plates opposite

PIN diodes)

2π-detection

SiO2SiO2

0 cm

-165 °C

Temperature gradient

180-182Hg (αααα)0 °C

LABORATORY FOR RADIOCHEMISTRY AND ENVIRONMENTAL CHEMISTRY OF THE UNIVERSITY OF

BERN AND THE PAUL SCHERRER INSITUTE

S. Soverna, March 2002

Nuclear reaction: 238U(48Ca,3n)283112*

sf (T1/2 ≈ 3 min)

Over all efficiency of IVO: 50 %

Average beam intensity: 1 pµA

Target thickness: 1 mg/cm2

Expected production cross section 1 pb

4 detected 283112 fission events per week4 detected 283112 fission events per week

LABORATORY FOR RADIOCHEMISTRY AND ENVIRONMENTAL CHEMISTRY OF THE UNIVERSITY OF

BERN AND THE PAUL SCHERRER INSITUTE

S. Soverna, March 2002

48Ca-beam

238U-target

Recoil chamber

He He

PIN diodes with PIN diodes withSiO2SiO2 AuAu surfacessurfaces

Oven(850 °C)

SiO2- column with Pt-foil

N2 (l)(-196 °C)(+25 °C)(+25 °C)

COLD temperature gradient: +25 °C to -180 °C

Thermostats

0 cm 36 cm

+25 °C

-180 °C

180-182Hg (αααα) Rn (αααα)Rn (αααα)283112 (sf)

283112 (sf)

?? ??

LABORATORY FOR RADIOCHEMISTRY AND ENVIRONMENTAL CHEMISTRY OF THE UNIVERSITY OF

BERN AND THE PAUL SCHERRER INSITUTE

S. Soverna, March 2002

H.U. Aebersold , R. Dressler, Ch.E. Düllmann, B. Eichler, R. Eichler, H.W. Gäggeler, D. Piguet, L. Tobler, A. Türler

A.B. Yakushev

Z. Qin