"Dead-time" reduction of the "Dead-time" reduction of the detection system of the Dubna detection system of the Dubna

Gas-filled Recoil SeparatorGas-filled Recoil Separator

V.G.Subbotin, Yu.S.Tsyganov, V.G.Subbotin, Yu.S.Tsyganov, A.A.VoinovA.A.Voinov, A.M.Sukhov, A.N.Polyakov, S.N.Iliev, A.M.Sukhov, A.N.Polyakov, S.N.Iliev

Joint Institute for Nuclear Research, 141980 Dubna, RussiaJoint Institute for Nuclear Research, 141980 Dubna, Russia

XXI International Symposium on Nuclear Electronics and Computing. Bulgaria, Varna, 10-17 September, 2007.

XXI International Symposium on Nuclear Electronics and Computing. Bulgaria, Varna, 10-17 September, 2007.

Layout of the Dubna gas-filled recoil separator (DQQ configuration)Layout of the Dubna gas-filled recoil separator (DQQ configuration)

XXI International Symposium on Nuclear Electronics and Computing. Bulgaria, Varna, 10-17 September, 2007.

XXI International Symposium on Nuclear Electronics and Computing. Bulgaria, Varna, 10-17 September, 2007.

Layout of the Dubna gas-filled recoil separator (DQQ configuration)Layout of the Dubna gas-filled recoil separator (DQQ configuration)

XXI International Symposium on Nuclear Electronics and Computing. Bulgaria, Varna, 10-17 September, 2007.

Si focal plane box of PIPS detectorsSi focal plane box of PIPS detectors

Particals’ signals: EVRs, alpha-, FFEfficiency• 87% of 4p for a-particles• 100% of 4p for FFResolution• 60 keV for focal plane detectors• 100 keV for side detectors• Dy = 0.9-1.9 mm for EVR-α

correlations and 0.5-0.9 mm for EVR-SF

12 strips 40mm*10mm each in focal plane surrounded by 8 side detectors 40mm*40mm without position sensitivity and 3 additional detectors in “veto” mode

XXI International Symposium on Nuclear Electronics and Computing. Bulgaria, Varna, 10-17 September, 2007.

Block diagram of the measuring electronics (only one detector circuit is shown Block diagram of the measuring electronics (only one detector circuit is shown completely).completely).

5 6 7

98

1

1B1

1T14

6 7

6 7

4 76

3

3

2

2

Eff position

Ea и Eff energy

Eff energy

Ea и Erecoil position

Logic of registration1 E

1 - position-sensitive strips of Si detector.2 - charge-sensitive preamplifier micro Catsa.3 - sum-invert-amplifier SU-206K.4 - amplifier SU-4K.5 - amplifier ORTEC575.6 - analog multiplexer AM-206K.7 - ADC PA-24K.

Measuring CAMAC Crate

8 - analog discriminator of energies DF-202.9 - logical block KL-203 (to control all ADCs).10 - charge-sensitive preamplifier PA-201.11 - timing filter amplifier Polon 1501.12 - nanosecond delay Polon 1506.13 - constant fraction discriminator.14 - T/A converter Polon 1701A.

71413

131211

1110

10

TOF

"stop""start"

XXI International Symposium on Nuclear Electronics and Computing. Bulgaria, Varna, 10-17 September, 2007.

Diagram of the logic of the registration of nuclear reactions products at DGFRSDiagram of the logic of the registration of nuclear reactions products at DGFRS

TOF-chamber

"stop"

"start"

blocking ofTOFselect

DF-201

Еrecoil >Еthreshold

TOF

1 chip

2 chip

3 chip

side

coincidencen > 2

1

&

ALL SIGNALS

TOFselect

anticoin-cidence

1

&

(TOFselect)Х(DECAY)Х(DEAD-TIMEmain)Х(DEAD-TIMEadd)

TOFDECAY

MAJORITYCOINCIDENCES

to КР-005

deblocking of ADCmain

beginning of measurementin КС-011add

KL-203block

KL-033КК-202

Selected TOF

debloking of ADCadd

"+1" in КС-002main

Еrecoil >8 MeV

XXI International Symposium on Nuclear Electronics and Computing. Bulgaria, Varna, 10-17 September, 2007.

The new logical block KL-203 to control the work of ADCsThe new logical block KL-203 to control the work of ADCs

XXI International Symposium on Nuclear Electronics and Computing. Bulgaria, Varna, 10-17 September, 2007.

SummarySummary

• The new logical block was designed and tested in the test reaction natYb+ 48Ca (for example,

220Th with T10 μs). “Dead-time” of the modern registration system is 8 s.

• In the experiment 249Cf+ 48Ca three decay chains originating from the parent isotope 294118

were detected (the half-lives of all the nuclei are longer than about 1 ms).

• Further investigation of the region of superheavy nuclei, e.g, nuclides with Z=120 in the

reaction 244Pu+ 58Fe definitely requires applying of this system because of the short half-lives

(~10-50 s) expected for the isotopes 298,299120.

XXI International Symposium on Nuclear Electronics and Computing. Bulgaria, Varna, 10-17 September, 2007.

Thank youThank you

XXI International Symposium on Nuclear Electronics and Computing. Bulgaria, Varna, 10-17 September, 2007.

ReferencesReferences• Yu.A. Lazarev et al., JINR Report E7-93-57, Dubna (1993) p.203.• Yu.A. Lazarev et al., JINR Report P13-97-238, Dubna, 1997.• Yu.S. Tsyganov et al., Nucl. Instrum. Methods Phys. Res. A 392, 197 (1997).• I. Muntian, Z. Patyk and A. Sobiczewski, Acta Phys. Pol. B 32, 691 (2001); R Smolańczuk, Phys. Rev. C 56,

812 (1997); R. Smolańczuk and A. Sobiczewski, in Proceedings of XV Nuclear Physics Divisional Conference “Low Energy Nuclear Dynamics”, St. Petersburg, Russia, 1995, World Scientific, Singapore, p. 313.

• Yu.A. Lazarev et al., in Proceedings of the International School-Seminar on Heavy Ion Physics, Dubna, Russia, 1993, Report E7-93-274 (JINR, Dubna, 1993) Vol. 2, p. 497.

• Yu.Ts. Oganessian et al., in Proceedings of the 4th International Conference on Dynamical Aspects of Nuclear Fission, Častá-Papiernička, Slovak Republic, 1998, World Scientific, Singapore, 2000, p. 334.

• K. Subotic et al., Nucl. Instrum. Methods Phys. Res. A 481, 71 (2002).• V.G. Subbotin, A.N. Kuznetsov, JINR Report 13-83-67, Dubna, 1983.• V.A. Antukhov et al., JINR Report P10-90-589, Dubna (1990) p.20.• V.G. Subbotin, A.N. Kuznetsov, JINR Report 13-12953, Dubna, 1979.• A.N. Kuznetsov, JINR Report P13-87-188, Dubna, 1987.• N.I. Zhuravlev et al., JINR Report 10-8754, Dubna (1975) p.18.• A.M.Sukhov et al., JINR Report P13-96-371, Dubna, 1996.• N.I. Zhuravlev et al., JINR Report P10-88-937, Dubna, 1988.• N.I. Zhuravlev et al., JINR Report 10-8114, Dubna (1988) p.14.• Yu.S. Tsyganov, A.N. Polyakov, Nucl. Instr. and Meth. in Phys. Res. A 558, (2006) 329-332; A 573 (2007)

161; A 513 (2003) 413; Appl. Radiat. And Isotopes, v.47, no.4, (1996) 451.• V.G. Subbotin, S.N. Iliev, A.A. Voinov, JINR Report P13-2004-97, Dubna, 2004.• Yu.Ts. Oganessian et al., Phys. Rev. C 74, 044602 (2006).• Yu.Ts. Oganessian et al., in Proceedings of the International Symposium on Physics of Unstable Nuclei

“ISPUN07, Hoi An, Vietnam, 2007, World Scientific, Singapore, to be published.

XXI International Symposium on Nuclear Electronics and Computing. Bulgaria, Varna, 10-17 September, 2007.