Comparison of two data acquisition and processing systems of Moller polarimeter in Hall A of Jefferson Lab
Two data acquisition and processing systems are used simultaneously to measure electron beam polarization by Moller polarimeter in Hall A of Jefferson Lab (Newport News, VA, USA). The old system (since 1997) is fully functional, but is not repairable in case of malfunction (system modules are not...
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Vereshchaka, V.V. Glamazdin, O.V. Pomatsalyuk, R.I. 2015-04-14T06:19:40Z 2015-04-14T06:19:40Z 2014 Comparison of two data acquisition and processing systems of Moller polarimeter in Hall A of Jefferson Lab / V.V. Vereshchaka, O.V. Glamazdin, R.I. Pomatsalyuk // Вопросы атомной науки и техники. — 2014. — № 3. — С. 157-161. — Бібліогр.: 7 назв. — англ. 1562-6016 PACS: 07.05.Hd; 29.85.Ca https://nasplib.isofts.kiev.ua/handle/123456789/80275 Two data acquisition and processing systems are used simultaneously to measure electron beam polarization by Moller polarimeter in Hall A of Jefferson Lab (Newport News, VA, USA). The old system (since 1997) is fully functional, but is not repairable in case of malfunction (system modules are not manufactured anymore). The new system (since 2010) based on flash-ADC is more accurate, but currently requires more detailed adjustment and further improvement. Description and specifications of two data acquisition and processing systems have been given. The results of polarization measurements during experiments conducted in Hall A from 2010 to 2012 are compared. Для измерения поляризации пучка электронов мёллеровским поляриметром зала А лаборатории им. Джефферсона (Ньюпорт-Ньюс, Вирджиния, США) параллельно используются две системы сбора и обработки данных. Старая система (работает с 1997 года) полностью функциональна, но не подлежит ремонту в случае выхода из строя (модули системы сняты с производства). Новая система на базе флэш-АЦП (введена в эксплуатацию с 2010 года) предоставляет больше возможностей для улучшения точности измерений, но на данный момент требует более детальной настройки и дальнейших доработок. Представлены описание и характеристики двух систем сбора и обработки данных. Сравниваются результаты измерений поляризации во время экспериментов, проведенных в зале А с 2010 по 2012 годы. Для вимірювання поляризації пучка електронів мьоллерівським поляриметром залу А лабораторії ім. Джефферсона (Ньюпорт-Ньюс, Вірджинія, США) паралельно використовуються дві системи збору та обробки даних. Стара система (працює з 1997 року) повністю функціональна, але не підлягає ремонту в разі виходу з ладу (модулі системи зняті з виробництва). Нова система на базі флеш-АЦП (введена в експлуатацію з 2010 року) надає більше можливостей для покращення точності вимірювань, але на даний момент потребує більш детального налаштування і подальших доробок. Представлено опис та характеристики двох систем збору і обробки даних. Порівнюються результати вимірювань поляризації під час експериментів, проведених в залі А з 2010 по 2012 роки. This work was supported by the contract DE-AC05- 06OR23177 of the United States Department of Energy, on the basis of which the Jefferson Science Associates manages and operates the Jefferson Lab. en Національний науковий центр «Харківський фізико-технічний інститут» НАН України Вопросы атомной науки и техники Применение ускорителей в радиационных технологиях Comparison of two data acquisition and processing systems of Moller polarimeter in Hall A of Jefferson Lab Сравнение двух систем сбора и обработки данных мёллеровского поляриметра зала А лаборатории им. Джефферсона Порівняння двох систем збору та обробки даних мьоллерівського поляриметру залу А лабораторії ім. Джефферсона Article published earlier |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| collection |
DSpace DC |
| title |
Comparison of two data acquisition and processing systems of Moller polarimeter in Hall A of Jefferson Lab |
| spellingShingle |
Comparison of two data acquisition and processing systems of Moller polarimeter in Hall A of Jefferson Lab Vereshchaka, V.V. Glamazdin, O.V. Pomatsalyuk, R.I. Применение ускорителей в радиационных технологиях |
| title_short |
Comparison of two data acquisition and processing systems of Moller polarimeter in Hall A of Jefferson Lab |
| title_full |
Comparison of two data acquisition and processing systems of Moller polarimeter in Hall A of Jefferson Lab |
| title_fullStr |
Comparison of two data acquisition and processing systems of Moller polarimeter in Hall A of Jefferson Lab |
| title_full_unstemmed |
Comparison of two data acquisition and processing systems of Moller polarimeter in Hall A of Jefferson Lab |
| title_sort |
comparison of two data acquisition and processing systems of moller polarimeter in hall a of jefferson lab |
| author |
Vereshchaka, V.V. Glamazdin, O.V. Pomatsalyuk, R.I. |
| author_facet |
Vereshchaka, V.V. Glamazdin, O.V. Pomatsalyuk, R.I. |
| topic |
Применение ускорителей в радиационных технологиях |
| topic_facet |
Применение ускорителей в радиационных технологиях |
| publishDate |
2014 |
| language |
English |
| container_title |
Вопросы атомной науки и техники |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| format |
Article |
| title_alt |
Сравнение двух систем сбора и обработки данных мёллеровского поляриметра зала А лаборатории им. Джефферсона Порівняння двох систем збору та обробки даних мьоллерівського поляриметру залу А лабораторії ім. Джефферсона |
| description |
Two data acquisition and processing systems are used simultaneously to measure electron beam polarization by
Moller polarimeter in Hall A of Jefferson Lab (Newport News, VA, USA). The old system (since 1997) is fully
functional, but is not repairable in case of malfunction (system modules are not manufactured anymore). The new
system (since 2010) based on flash-ADC is more accurate, but currently requires more detailed adjustment and further
improvement. Description and specifications of two data acquisition and processing systems have been given.
The results of polarization measurements during experiments conducted in Hall A from 2010 to 2012 are compared.
Для измерения поляризации пучка электронов мёллеровским поляриметром зала А лаборатории им. Джефферсона (Ньюпорт-Ньюс, Вирджиния, США) параллельно используются две системы сбора и обработки данных. Старая система (работает с 1997 года) полностью функциональна, но не подлежит ремонту в случае выхода из строя (модули системы сняты с производства). Новая система на базе флэш-АЦП (введена в эксплуатацию с 2010 года) предоставляет больше возможностей для улучшения точности измерений, но на данный момент требует более детальной настройки и дальнейших доработок. Представлены описание и характеристики двух систем сбора и обработки данных. Сравниваются результаты измерений поляризации во время экспериментов, проведенных в зале А с 2010 по 2012 годы.
Для вимірювання поляризації пучка електронів мьоллерівським поляриметром залу А лабораторії ім. Джефферсона (Ньюпорт-Ньюс, Вірджинія, США) паралельно використовуються дві системи збору та обробки даних. Стара система (працює з 1997 року) повністю функціональна, але не підлягає ремонту в разі виходу з ладу (модулі системи зняті з виробництва). Нова система на базі флеш-АЦП (введена в експлуатацію з 2010 року) надає більше можливостей для покращення точності вимірювань, але на даний момент потребує більш детального налаштування і подальших доробок. Представлено опис та характеристики двох систем збору і обробки даних. Порівнюються результати вимірювань поляризації під час експериментів, проведених в залі А з 2010 по 2012 роки.
|
| issn |
1562-6016 |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/80275 |
| citation_txt |
Comparison of two data acquisition and processing systems of Moller polarimeter in Hall A of Jefferson Lab / V.V. Vereshchaka, O.V. Glamazdin, R.I. Pomatsalyuk // Вопросы атомной науки и техники. — 2014. — № 3. — С. 157-161. — Бібліогр.: 7 назв. — англ. |
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| fulltext |
ISSN 1562-6016. ВАНТ. 2014. №3(91) 157
APPLICATION OF ACCELERATORS IN RADIATION TECHNOLOGIES
COMPARISON OF TWO DATA ACQUISITION AND PROCESSING
SYSTEMS OF MOLLER POLARIMETER IN HALL A
OF JEFFERSON LAB
V.V. Vereshchaka, O.V. Glamazdin, R.I. Pomatsalyuk
National Science Center “Kharkov Institute of Physics and Technology”, Kharkov, Ukraine
E-mail: vadik@kipt.kharkov.ua
Two data acquisition and processing systems are used simultaneously to measure electron beam polarization by
Moller polarimeter in Hall A of Jefferson Lab (Newport News, VA, USA). The old system (since 1997) is fully
functional, but is not repairable in case of malfunction (system modules are not manufactured anymore). The new
system (since 2010) based on flash-ADC is more accurate, but currently requires more detailed adjustment and fur-
ther improvement. Description and specifications of two data acquisition and processing systems have been given.
The results of polarization measurements during experiments conducted in Hall A from 2010 to 2012 are compared.
PACS: 07.05.Hd; 29.85.Ca
1. MOLLER POLARIMETER
The Moller polarimeter of Hall A was designed in
NSC KIPT jointly with Jefferson Lab [1, 2]. The polar-
imeter is intended for measuring electron beam polari-
zation in energy range 0.8…11.0 GeV in Hall A of Jef-
ferson Lab.
The polarimeter consists of polarized electrons tar-
get, magnetic spectrometer and detector (Fig. 1). Moller
electrons, emerging due to interaction of electron beam
and target, are analyzed by magnetic spectrometer. The
spectrometer comprises four quadrupole (Q1, Q2, Q3,
Q4) and one dipole magnets. Scattered electrons are
focused by quadrupole magnets in horizontal plane at
the input of dipole magnet. The dipole magnet reflects
these electrons down to detector.
Fig. 1. Diagram of the Moller polarimeter of Hall A:
side view (a), top view (b)
The electrons detector consists of two total absorp-
tion calorimeters, which allow to detect Moller events in
coincidences. Each calorimeter has four channels. Pho-
tomultipliers are fastened at the output ends of calorime-
ter units. Before each calorimeter there is an aperture
detector made of plastic scintillator and divided into
four sections.
Detection of Moller event is carried out by coinci-
dence of signals from left and right detectors; this al-
lows reducing the impact of background events.
Typical load of the detector during measurements is
100…200 kHz in one arm and 50 kHz in coincidences.
The quantity of coincidence events for different signs of
electron beam polarization and known value of target
polarization allow to determine electron beam polariza-
tion.
2. THE OLD DATA ACQUISITION SYSTEM
OF THE POLARIMETER
The Moller polarimeter of Hall A has two data ac-
quisition and processing systems:
1. The old system (Fig. 2) is based on CAMAC,
VME, NIM modules and has operated since 1997.
2. The new system is based on VME module flash-
ADC F-250 designed in Jefferson Lab, and was
introduced in 2009.
Fig. 2. Electronic circuit of the old data acquisition
system: 8LG – signals of 8 blocks of lead glass;
ADC – analog to digital converter; ∑L – total signal
from 4 left blocks; ∑R – total signal from 4 right blocks;
∑LR – total signal from 8 blocks; ApL – signal from left
aperture counter; ApR – signal from right aperture
counter; DCR – discriminator; DL – delay lines;
TDC – time to digital converter; PLU – programmable
logic unit; Н+, Н- – signals of + and - helicity;
SCL – scalers; DPS – data processing system
The old system is fully functional for all polarimeter
targets. It is time-tested and well-studied, but it has low
events recording speed; the system modules occupy
several crates, and its great number of interunit connec-
tions and cables reduces system reliability. Besides,
some system modules went out of production and are
not replaceable in case of malfunction.
a
b
ISSN 1562-6016. ВАНТ. 2014. №3(91) 158
The CODA system remotely controls the data acqui-
sition system and records data from the Moller polar-
imeter [5]. CODA is an online data acquisition system
for physical experiments, designed at Jefferson Lab.
Data analysis and processing is carried out by special
software on the basis of PAW package. PAW is a pack-
age of programs and libraries designed in European Or-
ganization for Nuclear Research (CERN) in FORTRAN
programming language.
The values from scalers are recorded for every “win-
dow” of beam helicity state (electron beam impulse with
polarization value “+” or “-” corresponding to logic sig-
nal value 1 or 0). The trigger for a “window” cessation is
a signal produced by another beam helicity value coming
from polarized electrons injector of accelerator [4].
Fig. 3. Spectrums of energy from detector units
of the old system
Fig. 3 shows energetic spectrums of electrons from
lead glass units of the Moller polarimeter detector. The
left column shows spectrums from four lead glass units
of detector’s left channel. The middle column shows
spectrums from four lead glass units of detector’s right
channel. Two upper spectrums of the right column show
total spectrums from four lead glass units in detector’s
left and right channels. The third spectrum from the top
of the right column shows coincidence spectrum of right
detector’s channel with left channel. The signals of the
right column are used directly for calculation of electron
beam polarization value; other values are used for vari-
ous checks and calibrations.
After normalization of total quantity of coincidence
events with certain helicity state (polarization direction)
to “windows” quantity and beam current value, and af-
ter subtraction of random coincidences the beam asym-
metry value is calculated.
2.1. THE OLD SYSTEM RECONSTRUCTION
The basic electronic modules are replaced by more
contemporary ones with higher bandwidth in order to
reduce dead time, and due to the impossibility of replac-
ing certain modules that gone out of production.
The main objectives of reconstructing the old data
acquisition system (DAQ) are:
• increase bandwidth (up to 200 MHz);
• reduction of readout time from ADC and TDC mod-
ules;
• replacement of programmable logic unit (PLU) gone
out of production;
• getting rid of CAMAC as an outdated and slow
standard.
The list of replaced modules:
• to increase bandwidth:
1. PLM LeCroy-2365 (frequency <75 MHz,
crate CAMAC) was replaced by PLM based on
CAEN V1495 (frequency 200 MHz, crate VME)
(Fig. 4).
2. Discriminator Ortec-TD8000 (frequency
< 150 MHz, crate CAMAC) was replaced by dis-
criminator P/S 708 (frequency < 300 MHz, crate
NIM).
• To reduce readout time:
1. ADC LeCroy 2249A (12 channels, crate
CAMAC) was replaced by ADC CAEN V792
(32 channels, crate VME).
2. TDC LeCroy 2229 (crate CAMAC) was re-
placed by TDC CAEN V1190B (64 channels, 0.1 ns,
crate VME).
The new modules have been tested and the software
is being developed for the reconstructed data acquisition
system.
Fig. 4. Diagram of programmable logic unit based
on module type of CAEN V1495
It is planned to use the old system after reconstruc-
tion at least up to the moment when the new system
based on flash-ADC is fully functional for operation
with two targets of the Moller polarimeter. It should be
noted that the new system was created for operation
with new target (with high magnetic field) and its soft-
ware is not intended for operation with old target (with
low magnetic field). As a result, while operating with
old target, the old system is mandatory whereas the new
one is optional. Moreover, the simultaneous use of two
systems allows to study systematic errors.
3. THE NEW DATA ACQUISITION SYSTEM
OF THE POLARIMETER
The main objective of introducing the new data ac-
quisition system is to reduce systematic errors in polari-
zation measurement. One of the components of meas-
ISSN 1562-6016. ВАНТ. 2014. №3(91) 159
urement systematic error is the impact of dead time of
events rerecord system. While polarization measuring
the dead time of data acquisition system depends upon
detectors loading or upon beam current. One of the
ways to reduce the impact of dead time is to increase
events rate registration and record speed by data acqui-
sition system. While developing the new system, it was
suggested to use module flash-ADC of F250 type, de-
signed in Jefferson Lab, with corresponding pro-
grammed record algorithm and event processing from
the polarimeter [6]. A block diagram of data acquisition
system on the basis of flash-ADC is shown in Fig. 5.
Fig. 5. New data acquisition system of the Moller
polarimeter
Data acquisition system comprises:
• flash-ADC F250;
• interrupt unit IO Flex;
• additional QDC module CAEN V792;
• scalers module CAEN V560;
• VME controller MVME6100;
• NIM crate and modules for ECL/NIM levels conver-
sion (not shown in the figure);
• Gigabit Ethernet network;
• controlling PC.
Electronic modules are in crate VME, which is in
experimental Hall A behind a shielding wall 10 meters
away from the detector. The computer is in experiment
control room 100 meters away from crate VME. The
additional module ADC V792 is used with flash-ADC
for supplementary record of levels of polarization sign
signals and synchronization signals. Scalers module
V560 is used for record of beam current, target location
on beam and signals of 100 kHz reference generator [3].
3.1. MODULE FLASH-ADC
Module flash-ADC is an integration of 16-channel
12-bit ADC of conveyor type with conversion frequency
250 MHz and programmable logic array FPGA in one
VME unit. From detector’s outputs of photomultipliers
analog signals, with amplitude up to +1 volt and dura-
tion 30…35 ns, are sent to module’s input and digitized
in ADC. The use of programmable logic array allows to
construct the whole logic circuit of events record and to
process digitized signals from ADC with clock frequen-
cy 250 MHz directly in the module. Functions of dis-
criminators, delay lines, coincidence circuits, scalers
and events record logics are programmed in FPGA
(Fig. 6).
Fig. 6. Module flash-ADC
After digitizing in ADC, signals from detector are
summarized for each calorimeter arm, and then total
signal is discriminated by level. If the level of total sig-
nal exceeds the preset discriminating threshold, then this
event (digitized signals of all channels) is recorded to
inner data buffer of the module; logic signals are formed
at the inputs of coincidence circuits.
Parameters of ADC operation are programmed and
downloaded to module when starting data acquisition
system on measuring [3].
The software for analyzing and processing measur-
ing data is designed on the basis of ROOT package (a
package of object-oriented programs and libraries de-
signed in European Organization for Nuclear Research
(CERN)) [7].
Data acquisition system based on flash-ADC, gener-
ates 2 types of triggers (events):
1. Helicity trigger, when scalers values are read;
2. Data trigger, when inner buffer is filled with data
from ADC.
At interrupt signals, the data of inner scalers and
ADC buffer are read into overall data flow of CODA
system and are transmitted via network to controlling
computer. The computer operates under Linux Red Hat
Enterprise and contains quad-core processor with fre-
quency 3.2 MHz and 2 TB of disk space. On PC the
data are written into files for further analysis and pro-
cessing. This system allows detecting and recording
data flow at speed up to 50 MB/s when speed of events
record in coincidence of left and right arms of the detec-
tor equals 160 kHz.
The ability of flash ADC to record every signal from
detector (data trigger) allows to study systematic errors.
Analysis of this information will improve the polarime-
ter GEANT model, increase the accuracy of measuring
average analyzing power, take into account such effects
as “pile-up events” (Fig. 7), Levchuk effect, etc. In op-
eration of flash-ADC data trigger certain errors have
been found, which prevent from using this universal
instrument in full measure. The errors are being elimi-
nated and software for data analysis is being developed.
ISSN 1562-6016. ВАНТ. 2014. №3(91) 160
Fig. 7. Example of data trigger (pile-up events)
Program package comprises program of data acqui-
sition online monitoring and programs of offline pro-
cessing. Program of monitoring allows to control the
quality of incoming information by displaying current
values of coincidence scalers, digitized analog signals
from each detector’s unit, amplitude spectrums of sig-
nals from the detector. Fig. 8 shows an example of dis-
played information by program of online monitoring.
The programs of offline processing allow to convert
data files from CODA into ROOT, to process and ana-
lyze data, and to obtain the results of beam polarization
measurement.
Fig. 8. Data from online monitoring program
4. COMPARISON OF MEASUREMENTS
RESULTS OF TWO SYSTEMS
To measure electron beam polarization it is neces-
sary to know the value of reaction analyzing power,
target polarization and beam asymmetry. As the two first
parameters are the same for both systems, the asym-
metry values measured by both systems are compared.
Fig. 9. Results of asymmetry measurement
by two systems
Fig. 9 shows the results of comparison of asymmetry
values measured by both data acquisition systems.
Blue dots are measurement results on the new sys-
tem based on flash-ADC, red dots are measurement
results on the old system. Horizontal straight lines are
averaged values of beam asymmetry. It is seen that the
difference in measurements by two systems is less than
1% and is not beyond the statistical error limits.
CONCLUSIONS
The Moller polarimeter of Hall A has two data ac-
quisition and processing systems operating simultane-
ously. The systems are based on different element bases
with different types of triggers (events).
The old system is fully functional, several modules
have been replaced, for the old ones are not subject to
repair in case of malfunction (gone out of production)
and in order to increase bandwidth frequency of the
system.
At the same time the new system based on high-
speed multichannel flash-ADC has been developed and
tested. This system allows to record events up to
160 kHz in coincidence and data acquisition up to
50 MB/s without significant increase of system dead
time; this allows to increase the accuracy of measuring
electron beam polarization by means of the Moller po-
larimeter [6].
The new system is more accurate but currently re-
quires more detailed adjustment and further improve-
ment.
This work was supported by the contract DE-AC05-
06OR23177 of the United States Department of Energy,
on the basis of which the Jefferson Science Associates
manages and operates the Jefferson Lab.
REFERENCES
1. A.V. Glamazdin, V.G. Gorbenko, L.G. Levchuk, et
al. Electron Beam Møller Polarimeter at Jlab Hall A
// Fizika. 1999, B8, p. 91-95 (in Russian).
2. E.A. Chudakov, A.V. Glamazdin, V.G. Gorbenko,
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ISSN 1562-6016. ВАНТ. 2014. №3(91) 161
СРАВНЕНИЕ ДВУХ СИСТЕМ СБОРА И ОБРАБОТКИ ДАННЫХ МЁЛЛЕРОВСКОГО
ПОЛЯРИМЕТРА ЗАЛА А ЛАБОРАТОРИИ им. ДЖЕФФЕРСОНА
В.В. Верещака, А.В. Гламаздин, Р.И. Помацалюк
Для измерения поляризации пучка электронов мёллеровским поляриметром зала А лаборатории
им. Джефферсона (Ньюпорт-Ньюс, Вирджиния, США) параллельно используются две системы сбора и об-
работки данных. Старая система (работает с 1997 года) полностью функциональна, но не подлежит ремонту
в случае выхода из строя (модули системы сняты с производства). Новая система на базе флэш-АЦП (введе-
на в эксплуатацию с 2010 года) предоставляет больше возможностей для улучшения точности измерений, но
на данный момент требует более детальной настройки и дальнейших доработок. Представлены описание и
характеристики двух систем сбора и обработки данных. Сравниваются результаты измерений поляризации
во время экспериментов, проведенных в зале А с 2010 по 2012 годы.
ПОРІВНЯННЯ ДВОХ СИСТЕМ ЗБОРУ ТА ОБРОБКИ ДАНИХ МЬОЛЛЕРІВСЬКОГО
ПОЛЯРИМЕТРУ ЗАЛУ А ЛАБОРАТОРІЇ ім. ДЖЕФФЕРСОНА
В.В. Верещака, О.В. Гламаздін, Р.І. Помацалюк
Для вимірювання поляризації пучка електронів мьоллерівським поляриметром залу А лабораторії
ім. Джефферсона (Ньюпорт-Ньюс, Вірджинія, США) паралельно використовуються дві системи збору та
обробки даних. Стара система (працює з 1997 року) повністю функціональна, але не підлягає ремонту в разі
виходу з ладу (модулі системи зняті з виробництва). Нова система на базі флеш-АЦП (введена в експлуата-
цію з 2010 року) надає більше можливостей для покращення точності вимірювань, але на даний момент пот-
ребує більш детального налаштування і подальших доробок. Представлено опис та характеристики двох сис-
тем збору і обробки даних. Порівнюються результати вимірювань поляризації під час експериментів, прове-
дених в залі А з 2010 по 2012 роки.
COMPARISON OF TWO DATA ACQUISITION AND PROCESSING SYSTEMS OF MOLLER POLARIMETER IN HALL A OF JEFFERSON LAB
1. MOLLER POLARIMETER
2. THE OLD DATA ACQUISITION SYSTEM OF THE POLARIMETER
2.1. THE OLD SYSTEM RECONSTRUCTION
3. THE NEW DATA ACQUISITION SYSTEM OF THE POLARIMETER
3.1. MODULE FLASH-ADC
4. COMPARISON OF MEASUREMENTS RESULTS OF TWO SYSTEMS
CONCLUSIONS
REFERENCES
СРАВНЕНИЕ ДВУХ СИСТЕМ СБОРА И ОБРАБОТКИ ДАННЫХ МЁЛЛЕРОВСКОГО ПОЛЯРИМЕТРА ЗАЛА А ЛАБОРАТОРИИ им. ДЖЕФФЕРСОНА
ПОРІВНЯННЯ ДВОХ СИСТЕМ ЗБОРУ ТА ОБРОБКИ ДАНИХ МЬОЛЛЕРІВСЬКОГО ПОЛЯРИМЕТРУ ЗАЛУ А ЛАБОРАТОРІЇ ім. ДЖЕФФЕРСОНА
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