TPC REPORT: 2010-2014
The manufacture of time projection chamber (TPC) vessels were completed. All four vessels are delivered
to JINR – see Fig.1. Cylinders length is L=340 cm and diameters – from D=54 cm and up to D=280 cm.
Fig.1 TPC vessels: C4 (top-left), C3 (top-right), C2 (bottom-left) and C1 (bottom-right).
The basic parameters of the MPD TPC chamber were optimized and fixed (see Table 1)
The geometry of MWPC and “Pad-plane” were designed. Anode wire diameter is D=25 µm and
step – 3.0 mm, cathode wire diameter is D=75 µm and step – 1.5 mm, gate wire diameter is D=75 µm and step – 1.0
1
mm. All gaps are h=3.0 mm (Fig.2, left). Pads have rectangular shape. 27 rows of pads with size of 4x12 mm2 are
on inner part and 26 rows of pads with size of 5x18 mm2 are on outer part (Fig.2, right).
Fig.2 Geometry of MWPC (left) and Pad-plane (right).
The serial Read-Out-Chamber (ROC) was designed and now are under construction. The production of two
prototypes is in progress (Fig.3). The pad-plane printed circuit board of TPC ROC is developed and given into
manufacture. The design of TPC rest parts is in progress too.
Fig.3 ROC Al frame with cooling tube (left) and
ROC isolated plate (right).
TPC prototype was built and tested (Fig.4). MWPC with anode wire pitch S=2.5 mm and anode-cathode
gap h=2 mm. TPC was tested with 2 gas mixtures: Ar/CH4 (90:10) and Ar/CO2 (80:20). For gas mixture Ar/CH4 the
optimal HV=1400 V (gas gain is about G=2x104), gas gain non-uniformity - ± 9 %, counting rate plateau – about
200 V for radioactive source Fe-55 (Eγ=5.6 Kev). For gas mixture Ar/CO2 the optimal HV=1600 V (gas gain is
about G=104). Suppression of ion feedback from MWPC to drift region is about K=104 at gas gain G=104.
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Fig.4 TPC prototype.
The test of 64-channels Front-End-Electronics Card (‘FEC64’) was finished with small ROC chamber
(Fig.5). A significant progress was achieved in preparation of Front-End-Electronics and DAQ system. The FEC’s
Software for Data Acquisition and Slow Control were developed. Example of signal shape from chamber pads is
presented for radioactive source Fe-55 after pedestal subtraction and ADC self-calibration.
Fig.5. Set up for test ‘FEC64’cards (left) and signal shape (right).
The new Front-End Card ’FEC64S’ was designed and assembled. The FEC’s Readout Controller
architecture design was completed. The FEC’s testing system based on the development kit ‘Cyclone-5 SoC’ was
created (Fig.6). Testing of ’FEC64S’ card is in progress.
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Fig.6. Testing system based on the kit ‘Cyclone-5 SoC’.
A schematic view of the TPC gas system is shown in Fig. 7. The technical design report of TPC gas system
is completed. Gas system will be built in collaboration with PNPI, Sankt-Petersburg, and industry. The main gas
system components were ordered.
Fig. 7: Schematic view of the TPC gas system.
TPC cooling system is under design. TPC drift volume temperature must be stable and cooled to reduce the
relative change in drift velocity. The main aim is to provide temperature stability of TPC gas volume with accuracy
better than 0.1°C. Each Front End Electronic Card (FEE) dissipates 8W. One ROC chamber includes 62 cards. The
1488 FEEs are the main heat source – 12 kW. 4 LV bus bars, are integrate into the SSW, will dissipate 2 kW. 24
ROC chambers will dissipate about 8 kW. So, total power dissipation can be estimated as 22 kW.
A schematic view of the TPC cooling units is shown in Fig. 8. Cooling system consists from distinct parts:

2 x 12 loops for the front-end electronic cooling;

2 x 2 loops the bus bar cooling and ROC covers;

2 x 2 loops the ROC cooling;

2 x 2 loops the inner thermal screen;

7 x 2 loops the outer thermal screen;

1 x 1 loops the resistor rods.
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Fig. 8: Schematic view of the TPC cooling system.
Fig. 9 shows the main components of the TPC cooling system. The basic components are the water coolant,
reservoir, water pump, heat exchanger, coolant temperature regulators, temperature sensors.
Fig. 9: Cooling system of the TPC.
In order to decrease thermal effect of the neighboring detectors the outer thermal screen and the inner
thermal screen will be constructed. The TPC thermal screen consists of thin aluminum panels with aluminum tube
through which cooling water will flow. The panel is a sandwich of two foils of aluminum, 0.2 mm thick each, and
adhesive material, 1 mm thick. The water flow rate will be optimized. Schematic views of the inner and outer
thermal screen are shown in Fig. 10.
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Fig. 10: The inner thermal screen (left) and one outer thermal screen panel (right)
The technical design report of TPC cooling system is in preparation.
Layout of TPC laser calibration system presented on Fig.11. Beams from each laser are split to four beams
and then, through 4 tubes placed inside the drift volume of TPC, where micro mirrors (diameter of active reflecting
surface is 1.3 mm) are illuminated to form 112 narrow calibration beams at each side of HV membrane. These 112
beams are distributed into 4 equidistant quasi planes of 28 beams in each, emitted from 4 tubes (see Fig. 1 and 2)
within the half of active volume of the TPC (224 beams in whole TPC). Distance between planes is 300 mm. Each
tube contains four bundles with 7 mirrors.
Fig. 11: Thin (1 mm diameter) beams emitted from the tube forms set of four planes with 28 beams in each of them.
Red plane is HV membrane.
Full set of micro-mirrors is ordered.
References
[1] A. Averyanov et al., “Time-Projection Chamber for MPD NICA project”, JINST 9 (2014) 09, C09036
[2] S. Vereshchagin "TPC MPD/NICA readout system", Poster, 41th meeting of the PAC for Particle Physics, June
25-26, 2014, JINR, Dubna, Russia
[3] A. Bazhazhin “Tracking of the Time Projection Chamber (TPC) for MPD/NICA”, Poster, 41th meeting of the
PAC for Particle Physics, June 25-26, 2014, JINR, Dubna, Russia
[4] A. Averyanov, A. Bajajin, V. Chepurnov, S. Chernenko, G. Cheremukhina, O. Fateev, A. Korotkova, F.
Levchanovskiy, Ju. Lukstins, S. Razin, A. Rybakov, S. Vereschagin, Yu. Zanevsky, S. Zaporozhets and V. Zruyev.
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"Time-Projection Chamber for the MPD NICA project", JINST 9 (2014) (Journal of Instrumentation), Volume 9, p.
1-10
<http://iopscience.iop.org/1748-0221/9/09/C09036/refs>
[5]
S.
Chernenko,
V.
Chepurnov,
D.
Kovalev,
V.
Ponomarev,
S.
Zanevsky, V. Zryuev. “2-dimensional GEM detector with FEE based on the nXYTER ASIC”.
JINST 9 (2014) (Journal of Instrumentation) C09026 (2014-09-24)
Razin,
Yu
[6]
S.
Chernenko,
V.
Chepurnov,
D.
Kovalev,
V.
Ponomarev,
S.
Razin,
Yu
Zanevsky, V. Zryuev. “2-dimensional GEM detector with FEE based on the nXYTER ASIC”.
Poster on the Conference “Instrumentation for Colliding Beam Physics" (INSTR14)”, Budker Institute of Nuclear
Physics (BINP), Siberian Branch of Russian Academy of Science, Novosibirsk, Russia, from 24 February to 01
March, 2014
[7] S.Vereschagin et al., “Time-Projection Chamber for MPD NICA project”, Report on the Conference
“Instrumentation for Colliding Beam Physics" (INSTR14)”, Budker Institute of Nuclear Physics (BINP), Siberian
Branch of Russian Academy of Science, Novosibirsk, Russia, from 24 February to 01 March, 2014
[8] S. Vereshchagin “Readout electronics for TPC MPD/NICA”, Report on the School for young scientists of JINR,
June 2-7, 2014, Alushta, Russia
[9] A. Bajajin "Electric field shape simulation for TPC MPD/NICA by ANSYS Maxwell". Report on the School for
young scientists of JINR, June 2-7, 2014, Alushta, Russia
http://indico-new.jinr.ru/conferenceOtherViews.py?view=standard&confId=30
[10] С.Верещагин "Система регистрации и сбора данных детектора TPC/MPD проекта NICA", МСК СЯФ
ОФН РАН 2014, НИЯУ МИФИ, Москва, Россия, 17 – 21 ноября 2014
[11] Ю.В. Заневский, С.В. Разин, А.Г. Бажажин, Ю. Лукстиньш, О.В. Фатеев, В.Ф. Чепурнов, С.П.
Черненко, А.В. Аверьянов, А.М. Короткова, С.В. Верещагин, В.Н. Зрюев, Г.А. Черемухина.
Труды XVIII Международной научной конференции молодых ученых и специалистов к 105-летию Н.Н.
Боголюбова (ОМУС-2014), 24-28 февр. 2014г., Дубна, Россия, с. 117-120, "Время-проекционная камера
(TPC) детектора MPD для коллайдера NICA", ISBN 978-5-9530-0384-1. УДК-51+53+57+621.039+004(092)
http://omus.jinr.ru/conference2014/conference_proceedings_2014.pdf
[12] Ю.В. Заневский, С.В. Разин, А.Г. Бажажин, Труды XVIII Международной научной конференции
молодых ученых и специалистов к 105-летию Н.Н. Боголюбова (ОМУС-2014), 24-28 февр. 2014г., Дубна,
Россия, с. 252-255, "Результаты моделирования электрического поля в TPC используя программный пакет
ANSYS Maxwell".
ISBN 978-5-9530-0384-1. УДК-51+53+57+621.039+004(092)
http://omus.jinr.ru/conference2014/conference_proceedings_2014.pdf
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