The electromagnetic CsI(Tl) calorimeter is one of the key systems in the Belle II detector. The calorimeter is aimed primarily at efficiently detecting photons over a wide energy range from several ...tens of MeV units to
GeV. A highly efficient data acquisition system is required for a continuous readout of signal events at a trigger rate corresponding to the maximum collider luminosity. Problems solved by such a system for the calorimeter of the Belle II detector are described.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
2.
Experiments at the Super Charm-Tau factory Achasov, Mikhail N.; Blinov, Vladimir E.; Bobrov, Alexander V. ...
Physics Uspekhi,
01/2024, Volume:
67, Issue:
1
Journal Article
Since 2018, the Belle II experiment has been running at KEK, at the SuperKEKB B-factory, with all detector subsystems taking data. One of the important detector systems is an electromagnetic ...calorimeter (ECL) that includes 8736 counters based on CsI(Tl) scintillation crystals. This report describes the data acquisition (DAQ) system that has been developed for ECL. Front-end electronics of ECL DAQ consist of several hundred highly configurable FPGA-controlled modules that utilize pipeline readout architecture and are able to handle a trigger rate up to 30 kHz. ECL front end electronics are initialized, configured and monitored by ECL DAQ software. The initialization library can work with several transport protocols, internally optimize requests to the electronics and perform caching of the configuration data. Configuration software manages and monitors more than 105 electronics parameters and updates them based on the calibrations. Continuous monitoring of ECL data quality is also implemented.
The electromagnetic calorimeter of the Belle II detector contains CsI(Tl) crystals of 30 cm length which have been used at the Belle experiment. We measure the light output degradation of CsI(Tl) ...crystals exposed to uniformly distributed absorbed dose. Four Belle typical crystals with known scintillation characteristics are irradiated with photons at a total dose of about 35 krad. Results show acceptable radiation hardness for the Belle II experiment conditions where the accumulated dose in crystals could reach 10 krad.
The design and construction work of the Belle II detector subsystems, including its electromagnetic calorimeter, is ongoing. The modification of the calorimeter includes the development of new ...electronics based on specially developed shaper-digitizer-signal-processing (Shaper DSP) modules. A shaper DSP module performs signal shaping, digitization, waveform analysis and provides a fast sum signal for trigger. The calorimeter includes 576 Shaper DSP modules. Recently mass-production stage started and the complete performance test for all modules is now necessary. To test a workability of modules and measure their parameters, a specialized testbench has been developed. The testbench allows one to study the signal shape, fast output, deviations from linearity, noise level and DSP logic. All test results are recorded in the database and some of them have graphical representation.
Data on the incidence of brucellosis and main trends in the development of situation on this infection in countries around the world under current conditions are provided in the review. A detailed ...analysis of epizootiological and epidemiological situation regarding brucellosis in the Russian Federation over the last decade and a forecast for human brucellosis incidence for 2024 are given. It is established that global situation on brucellosis in different regions of the world has undergone changes over the past 15–20 years. One can observe an almost twofold increase in the number of countries affected by brucellosis in the world. A relatively high brucellosis morbidity rates were recorded in some countries in Africa, Central Asia, South and South-East Asia, Central and South America. In countries of the European Union, there is a trend towards an increase in the number of human brucellosis cases associated with travel to enzootic countries. In the Russian Federation, an unstable epidemiological situation has been observed over the past 10 years. 3537 cases were identified. In 2022–2023, an emerging trend towards an increase in incidence of brucellosis among population by 30–50 % as compared to long-term average values was recorded, linked to occurrence of cattle epizooties, including at large livestock enterprises; formation of group epidemic foci in previously relatively brucellosis-free territories of the Central, Volga and Southern Federal Districts; and the deterioration of epizootic situation on brucellosis in the Republic of Dagestan and a number of constituent entities of Siberian Federal District. Situation on brucellosis in the Smolensk and Bryansk Regions requires closer attention. There are signs of rooting (enzooty) and further spread of brucellosis among cattle there in 2023. In 2024, incidence rate can be predicted to be 35–40 % higher than the long-term average values. The number of human brucellosis cases may be approximately 480–530 (0.32–0.36 per 100 000 population).
Electromagnetic calorimeter for Belle II Belle-ECL; Aulchenko, V; Bobrov, A ...
Journal of physics. Conference series,
01/2015, Volume:
587, Issue:
1
Journal Article
Peer reviewed
Open access
The electromagnetic calorimeter of the BELLE II detector for experiments at Super B-factory SuperKEKB is briefly described. The project of the calorimeter upgrade to meet severe background conditions ...expected at the upgraded KEK B factory is presented.
The designed luminosity of the Belle detector after its upgrade (Belle II experiment) is 40 times higher than the maximum reached before its shutdown for an upgrade. This necessitates an upgrade of ...the Belle DAQ system together with the upgrade of many detector's subsystems. In this paper the upgrade of the Belle Electromagnetic calorimeter (ECL) electronics is described.
A
bstract
We present measurements of the branching fractions for the decays
B
→
Kμ
+
μ
−
and
B
→
Ke
+
e
−
, and their ratio (
R
K
), using a data sample of 711 fb
−
1
that contains 772 × 10
6
B
B
¯
...events. The data were collected at the ϒ(4
S
) resonance with the Belle detector at the KEKB asymmetric-energy
e
+
e
−
collider. The ratio
R
K
is measured in five bins of dilepton invariant-mass-squared (
q
2
):
q
2
∈ (0
.
1
,
4
.
0)
,
(4
.
00
,
8
.
12)
,
(1
.
0
,
6
.
0), (10
.
2
,
12
.
8) and (
>
14
.
18) GeV
2
/c
4
, along with the whole
q
2
region. The
R
K
value for
q
2
∈ (1
.
0
,
6
.
0) GeV
2
/c
4
is
1.03
−
0.24
+
0.28
± 0
.
01. The first and second uncertainties listed are statistical and systematic, respectively. All results for
R
K
are consistent with Standard Model predictions. We also measure
CP
-averaged isospin asymmetries in the same
q
2
bins. The results are consistent with a null asymmetry, with the largest difference of 2.6 standard deviations occurring for the
q
2
∈ (1
.
0
,
6
.
0) GeV
2
/c
4
bin in the mode with muon final states. The measured differential branching fractions,
d
ℬ
/dq
2
, are consistent with theoretical predictions for charged
B
decays, while the corresponding values are below the expectations for neutral
B
decays. We have also searched for lepton-flavor-violating
B
→
Kμ
±
e
∓
decays and set 90% confidence-level upper limits on the branching fraction in the range of 10
−
8
for
B
+
→
K
+
μ
±
e
∓
, and
B
0
→
K
0
μ
±
e
∓
modes.
The construction of the SuperKEKB electron-positron collider and upgrade of the Belle II spectrometer are going on at KEK aiming at high precision measurements in bottom, charm and tau flavor ...sectors. We describe a replacement of the electronics for the CsI(Tl) crystal calorimeter with PIN-PD readout to match the luminosity increase up to 8 x 10 super(35) cm super(-2)s super(-1) at maximum. A plan to replace CsI(Tl) crystals with pure CsI in the endcaps is also mentioned.
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