II-9. Instrumentation

RIKEN Accel. Prog. Rep. 54 (2021)

RIKEN Accel. Prog. Rep. 54 (2021)

Upgrade of the Si-CsI array TiNA for transfer reactions at OEDO
B. Mauss,∗1 J. W. Hwang,∗2,∗3 D. Suzuki,∗1 N. Ma,∗2 N. Imai,∗2 M. Dozono,∗2 S. Michimasa,∗2 T. Sumikama,∗1S. Ota,∗2 C. Iwamoto,∗1 N. Iwasa,∗3 and F. Endo∗3TiNA is an array of silicon strip detectors (SSDs)
and CsI(Tl) crystals for measuring recoiling particles
from transfer reactions.1) Initially, TiNA had six telescopes in a lamp-shade conﬁguration. Each telescope
had a YY1-type single-sided SSD of Micron and twoCsI crystals behind the SSD, the total active area of
which is 6 × 5 cm2 . The telescopes were placed 8 to
10 cm away from the reaction point and surrounded
the beam axis. They covered a laboratory angle rangeof 100◦ to 150◦ . TiNA has been used in several transfer
experiments at RIBF.2,3)
Upcoming experiments using transfer reactions,however, require a larger solid angle and better resolutions in angle and energy. For instance, for the50Ca(d, p) experiment at the OEDO beamline, an excitation energy resolution better than 200 keV in σshould be achieved. The upgrade project of TiNA has
been launched to fulﬁll these requirements. In this report, we present the details of the improvements ofTiNA and the results of the oﬄine test.
Figure 1 shows the upgraded structure of TiNA.
Four more telescopes are introduced to cover a larger
solid angle, and they are located between the target
and the YY1 telescopes. Each has a 0.3 mm-thick
TTT2-type double-sided SSD (DSSD) of Micron andfour 25 mm-thick CsI(Tl) crystals. The DSSD covers 97 × 97 mm2 . The CsI crystals placed behind canmeasure relatively high-energy charged particles (e.g.,protons with E < 80 MeV). The angular resolution is
improved to be less than 0.5◦ . Three new trapezoidal
CsI crystals are brought in to fully cover the active
area of the original YY1 SSD.
A new electronic system for the TTT2 has been established. Since the additional detectors have morethan a thousand channels, we employ the General
Electronics for TPCs (GET), an integrated system forsignal processing including analog to digital converters (ADCs), trigger logic, and ampliﬁers for detectors
with many channels.4) For the connection between theDSSDs and GET, ﬂexible-printed-circuit (FPC) connectors and circuits for the separation of signals froma DC bias are used. A new scattering chamber housing
was prepared as well.
The performance of the GET system to readout thesignal from the TTT2 was tested at RIKEN. The test
bench consisted of one TTT2 and a standard 241 Am
α-source installed inside the new TiNA chamber. The∗1∗2∗3∗4CsI(Tl)

YY1 x 6 (SSSD)

Beam
TTT2 x 4 (DSSD)
TargetHolder

RIKEN Nishina Center
Center for Nuclear Study, the University of Tokyo
Center for Exotic Nuclear Studies, Institute for Basic Science
Department of Physics, Tohoku University- 114 -Fig. 1. Schematic drawing of TiNA after upgrade. The
YY1-type SSDs and CsI(Tl) crystals of original TiNA
are colored with blue and red, respectively. The new
TTT2-type DSSDs and CsI(Tl) crystals are coloredwith green and purple, respectively.

detector was fully depleted at −55 V. The GET system
consisted of an application-speciﬁc integrated circuit(ASIC) and ADC (AsAd) board connected to a totalof 256 strips and a reduced version of the Concentration Board (rCoBo). The system was triggered by aninternal multiplicity signal of rCoBo. A pulse-shapeanalysis is performed on the GET digitized signal toextract the energy of particle hits. The resolution obtained on the 241 Am α-spectrum is 28 keV (FWHM)
for the 5.485 MeV peak. More tests have been performed with the full system using 4 AsAd boards connected to a normal CoBo. It yielded similar results.
In conclusion, the TiNA array was upgraded by integrating new DSSDs, CsI detectors, and the GET system. The performance was tested using a standard
α-source. The results demonstrate the high resolution capabilities allowed by the new design and electronic circuit. This resolution was used to simulate
the 50 Ca(d, p) reaction. The overall excitation energy
resolution is less than 150 keV in σ, which is within
the experiment speciﬁcation. The full system of TiNA
will be tested in-beam at the Tandem accelerator of
the University of Kyushu in January 2021.
References

1) P. Schrock et al., CNS Annu. Rep. 2016, CNS-REP-96,7 (2017).
2) K. Wimmer et al., CNS Annu. Rep. 2017, CNS-REP97, 7 (2019).
3) N. Imai et al., CNS Annu. Rep. 2018, CNS-REP-98, 1(2020).
4) E. C. Pollacco et al., Nucl. Instrum. Methods Phys. Res.
A 887, 81 (2018).

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