Ⅱ-9. Instrumentation

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RIKEN Accel. Prog. Rep. 49 (2016)

Upgrade of trigger circuits and DAQ modules for SAMURAI

Y. Togano,∗1,∗2 T. Isobe,∗2 H. Baba,∗2 J. Tsubota,∗1,∗2 S. Araki,∗3 S. Kawase,∗3 Y. Kondo,∗1,∗2

S. Takeuchi,∗1,∗2 and H. Otsu∗2

Many kinds and a large number of detectors are em-ployed in experiments with SAMURAI. Users oftenneed many complex triggers by using many kinds ofdetectors to select a certain reaction channel. In ad-dition, the trigger rate is often as high as 2 kHz. Tocope with such increased number of triggers and highertrigger rate, the circuits and modules for the data ac-quisition system (DAQ)1) were upgraded, which con-sisted of two parts, introduction of a trigger selectionmodule and installation of new modules to shorten thedead time of the DAQ system. This paper reports onthese two upgrades.

For experiments at SAMURAI, the four trigger in-puts of the normal GTO module2) is often not enough.Therefore the trigger selector GTO3) was newly intro-duced. Figure 1 shows the diagram of the new trig-ger circuits for SAMURAI. The trigger selector GTOnamed as sdgto02 can input 16 triggers and can out-put downscaled individual triggers and “or” of them.The output from sdgto02 coincides with the “Beam”trigger generated from F13 plastics, and then vetoedby the busy signal and SSM (bit signal to synchronizecircuits with DAQ start/stop) from the normal GTOmodule named as sdgto01. The accepted trigger is dis-tributed to all DAQ branches of the SAMURAI DAQsystem. This circuit configuration was used for theSAMURAI21 experiment4).The SAMURAI DAQ system consists of many DAQ

branches such as B3F, BDC, FDC1, FDC2-1, FDC2-2,NEBULA, and HODF. The details of the SAMURAIDAQ system can be found in Ref. 1. The B3F branchaccumulates information from beam-line plastics andtriggers. The BDC branch is used to accumulate datafrom BDC1, BDC2, and ICB. The FDC1, FDC2-1,and FDC2-2 branches are for drift chambers. The datafrom FDC2 are processed by using two DAQ branches,FDC2-1 and FDC2-2, to cope with the large number

Fig. 1. Diagram of new trigger circuits of SAMURAI.

∗1 Department of Physics, Tokyo Institute of Technology∗2 RIKEN Nishina Center∗3 Faculty of Engineering Sciences, Kyusyu University

Table 1. Summary of typical dead time of the DAQ

branches in SAMURAI21 and DAY-ONE experiments.

SAMURAI21 [µs] DAY-ONE [µs]

B3F 145 360FDC1 180 170FDC2-1 210 270FDC2-2 180 220

of channel of FDC2. The NEBULA branch is for theneutron detector NEBULA. The HODF branch is usedto accumulate data from HODF (+ICF and TED, de-pending on experiments).

To shorten the dead time of the DAQ system1),we upgraded the system for the B3F branch andchanged the VME controller for the FDC1, FDC2-1,and FDC2-2 branches. The B3F branch is replaced bya VME-based system from a CAMAC-based system.The new VME-based system contains TDC (MTDC32from Mesytec GmbH), QDC (MQDC32 from MesytecGmbH), two scalers (SIS3820 from SIS GmbH), anda interrupt register (RPV-130 from Repic Co.). TheVME controllers for the FDC1, FDC2-1, and FDC2-2branches are replaced from SBS-620 (SBS Technolo-gies) to V7768 (Abaco systems).

Table 1 summarizes the typical dead time of DAQbranches in SAMURAI21 experiment and SAMURAIDAY-ONE experiment. For the B3F branch, the deadtime was 145 µs, much shorter than that of the previ-ous system (360 µs) in the SAMURAI DAY-ONE ex-periment5). For FDC2-1 and FDC2-2, the dead timein SAMURAI21 was ∼20% shorter than those in theDAY-ONE experiment. The time resolution of the F13plastics with the new VME system was obtained to beabout 46 ps for the SAMURAI21 experiment, showingthat the performance of the VME crate is enough forSAMURAI.

With these upgraded DAQ branches, the live time inthe SAMURAI21 experiment was 75% for 1.1 kHz trig-gers. The bottleneck of the dead time is BDC, whichhad 240 µs dead time in the SAMURAI21 experiment,which can be improved by replacing the VME con-troller to V7768.

References1) H. Otsu et al.: RIKEN Accel. Prog. Rep. 46, 146 (2013).2) H. Baba et al.: RIKEN Accel. Prog. Rep. 47, 235

(2014).3) H. Baba et al.: In this report.4) Y. Kondo et al.: In this report.5) T. Kobayashi et al.: Nucl. Instrum. Meth. B 317, 294

(2013).

Tests of the Advanced Implantation Detector Array (AIDA) at RIBF

C.J. Griffin,*1 T. Davinson,*1 A. Estrade,*1 D. Braga,*2 I. Burrows,*3 P. Coleman-Smith,*3 T. Grahn,*4 A. Grant,*3

L.J. Harkness-Brennan,*4 G. Kiss,*5 M. Kogimtzis,*3 I. Lazarus,*3 S. Letts,*3 Z. Liu,*1 G. Lorusso,*5 K. Matsui,*5,*6

S, Nishimura,*5 R.D. Page,*4 V. Phong,*5 M. Prydderch,*2 V. Pucknell,*3 S. Rinta-Antila,*4 O. Roberts,*7 D. Seddon,*4

J. Simpson,*3 J. Strachan,*3 S.L. Thomas*2 and P.J. Woods*1

Fig. 1: A photograph of the fully constructed AIDA assembly.

The Advanced Implantation Detector Array (AIDA)1)

represents the latest generation of silicon implantation detectors for use in decay spectroscopy measurements of exotic nuclei at fragmentation beam facilities. Designed to improve upon current generation, AIDA features high detector pixilation and fast overload recovery (~1 s), required at modern RI facilities with increasingly high secondary beam intensity and access to isotopes with very short half-lives. Application specific integrated circuits (ASICs)2) were specifically designed to meet the above requirements. One ASIC can process 16 data channels, each with two dedicated preamplifiers: one, with selectable gain to cover the low and medium energy ranges of up to 1 GeV, and the other, a low-gain amplifier covering the full dynamic range of 20 GeV. Detector signals are carried via flexible Kapton PCBs to the front end electronics (FEE) cards, which support 64 channels of instrumentation. The FEE cards contain: multiple analogue-to-digital converters (ADCs) for use in signal processing; a field-programmable gate array (FPGA) for control, signal processing and data management; and additional supporting electronics. As each FEE card runs a separate data acquisition system

School of Physics and Astronomy, University of Edinburgh STFC Rutherford Appleton Laboratory STFC Daresbury Laboratory School of Physical Sciences, University of Liverpool RIKEN Nishina Centre Department of Physics, University of Tokyo School of Engineering and Mathematics, University of Brighton

(DAQ), reading data from just 64 channels, dead-time is vastly reduced compared to current generation detectors dealing with high pixelation. Fig. 1 shows the full AIDA assembly. To study the response of AIDA to implantation of heavy ions, in-beam tests have been conducted at the Radioactive Ion Beam Factory (RIBF) at RIKEN. The tests were conducted parasitically to experiments part of the SEASTAR campaign, placing AIDA at the F11 focal plane.In the most recent test configuration, AIDA comprised three MSL BB18-1000 type DSSSDs, each with a thickness of 1mm and featuring 128 strips with a 0.625 mm pitch in both the x and y directions.These tests have demonstrated both the capability of AIDA to detect position and energy of fast fragment beams and their decay products, as well as our ability to integrate multiple DAQs – AIDA, and the BigRIPS in-beam detectors for particle identification – into one data stream.DAQ integration is achieved through the timestamping of all data items in each data stream, which are then time-ordered in the analysis software. This forms one continuous stream of data containing information on the implant positions, decay positions and energies, and particle identification data from BigRIPS. A method has also been developed by which the BRIKEN/AIDA DAQs can be synchronised, which will be tested with the full-scale BRIKEN array once it has been assembled. In addition to this, an online monitor has been developed to check the status of the DAQ synchronisation and to provide some basic analysis in real-time. Preliminary analysis of the data collected during these tests is underway, from which we hope to see some early results in the near future. Further steps must still be taken to better understand the efficiency of the analysis software in correlating implants and decays, and in characterising the background to reduce the likelihood of random correlations. With promising progress being made on all fronts, AIDA is planned for use at RIBF throughout 2016-2017 with two main focuses: -decay half-life and decay spectroscopy measurements with the EURICA -ray detector, and measurements of -delayed neutron emission probabilities as part of the BRIKEN collaboration.

References1) C.J. Griffin, T. Davinson, A Estrade et al., POS(NIC XIII) 097 20142) D. Braga, P. J. Coleman-Smith, T. Davinson, I. H. Lazarus, R. Page, and S. Thomas in ANIMMA 2nd International Conference, IEEE, 2011.

Tests of the Advanced Implantation Detector Array (AIDA) at RIBF