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Abstract: Photoinduced electron transfer between octadecylrhodamine B (a hole donor) and N, N-dimethyl-1-napthylamine (hole acceptor), located in the head group region of sodium dodecylsulfonate micelles, has been examined for different acceptor concentrations using time resolved fluorescence. The experimental results were analyzed using the Marcus distance-dependent transfer rate modified to take into account the heterogeneous nature of the micelles. Diffusion of the donor/acceptors is included in the theoretical analysis. The results are compared with earlier experiments involving the same donor–acceptor combination but in a different type of micelle. [Copyright &y& Elsevier]

Abstract: Cationic dyes, like alkyl styryl pyridinium dyes, are found to interact with anionic surfactant systems differently according to their structural differences. The absorption and emission spectral data of the dyes in various organic solvents and in a wide range of surfactant concentration reveal a variation in the solubilization pattern of the dyes with varying alkyl chain at the pyridinium end. The existence of monomer and H/J-stacked dimers in aqueous medium as well as in surfactant media gets evidence from the spectral data. The difference in binding constant of the dyes with the surfactant aggregates is rationalized through the change in hydrophobicity of the dye due to change in alkyl chain. [Copyright &y& Elsevier]

Cotarnine is an important organic molecule having tetrahydroisoquinoline core. Cotarnine core exhibits very important biological property. Its biological property changes by correct functionalization of core structure to form new molecules. Herein we describe the developments of chemistry of cotarnine and its derivatives in terms of property, synthesis, reactivity and biological application from scratch to complex core. This review will update the information about cotarnine chemistry and its application for synthesis of different bioactive product. Image 1 • Cotarnine skeleton in tetrahydroisoquinoline alkaloids. • Synthesis, reactivity and biological activity of cotarnine and its analog. • Chemistry of cotarnine skeleton in noscapine and noscapinoids. • Expansion and functionalization of cotarnine ring in noscapine. • Functionalization of cotarnine and chiral semi-cotarnine. [ABSTRACT FROM AUTHOR]

Ofloxacin (OFX) which is poorly soluble fluroquinolone drug exists as cationic form in acidic pH and zwitterionic form in neutral pH. The behaviour of host-guest interaction of Ofloxacin (OFX) with β-Cyclodextrin (β-CD) has been investigated by fluorescence quenching method in acidic and neutral medium using copper as quencher at various temperatures. Using the Benesi−Hildebrand relationship, the stochiometry of the host-guest complexation has been estimated. The incorporation of OFX inside the cavity of β-CD was revealed from fluorescence anisotropy measurement. Effect of temperature on the Stern-Volmer quenching constant (K SV ) and binding constant (K) has been analyzed and a suitable mechanism has been proposed on the nature of quenching. Using Vant-Hoff equation and Gibbs-Helmholtz equation, thermodynamic parameter change of enthalpy (ΔH), entropy (ΔS) and Free Energy (ΔG) has been determined, negative value of ΔH and positive value of ΔS validate that hydrophobic interaction between drug and quencher and negative value of ΔG suggest the complex is spontaneous in nature. [ABSTRACT FROM AUTHOR]

The longwall mining is considered to be the best coal mining practices due to vast recovery of coal over other forms of underground as well as opencast mining methods. But the actual scenario is quite opposite in India where productivity form of the longwall mines lags far behind than the desired level. Irregular caving and sudden rock bursts, which are very hazardous for mine workers and equipment. Usually these are major problem faced by bulk of Indian longwall faces and which are due to the presence of thick sandstone beds as overlying strata. Thus to keep an eye on the rock bursts, it is very necessary to monitor the stressed zones in the hanging overlying strata above and behind the panel. Earlier Correlation Integral ‘ C ’ and Correlation Fractal Dimension ‘ Dc ’ has been very helpful in monitoring the stressed zones for several great earthquakes in past. Following the same way, in the present study we have used the mine-induced microseismic data obtained from the retreating longwall panel using various monitoring instruments to calculate the Correlation Fractal Dimension ‘ Dc ’ for monitoring the stress levels and fractures in the overlying strata and also for spatio-temporal forecasting of roof-falls. The variation of blast charge size with Fractal Dimension is also studied. The use of Fractal Dimension has been very effective in obtaining the precursory signatures for roof-fall, thus ensuring safety in the mines. [ABSTRACT FROM AUTHOR]

The silicon vertex detector (SVD) is a four-layer double-sided strip detector installed at the heart of the Belle II experiment, taking data at the high-luminosity B -Factory SuperKEKB since 2019. SVD has been operating smoothly and reliably, showing a stable and above-99% hit efficiency, and a large signal-to-noise ratio in all sensors. In June 2022 the data-taking of the Belle II experiment was stopped for the Long Shutdown 1, primarily required to complete the vertex detector (VXD) with the inner two-layer DEPFET detector and to upgrade several components of the accelerator. This article reports on the excellent performance of SVD in terms of the signal-to-noise ratio, the hit position resolution, as well as the hit-time resolution. We briefly describe the challenges and delicate phases of the VXD re-installation and the SVD status for operation starting in early 2024. In SVD layer 3, which is closest to the interaction point, the average occupancy has been less 0.5%, well below the estimated limit for acceptable tracking performance. However, higher machine backgrounds are expected at increased luminosity, and so also increased hit occupancy. To enhance the robustness of offline software in a high-background environment, new algorithms of background suppression using the excellent SVD hit-time information have been developed, which allows a significant reduction of the fake rate, while preserving the tracking efficiency. With the increasing luminosity also the radiation levels are expected to increase, with possible deterioration of the sensor performance. The SVD integrated dose is estimated by the correlation of the SVD occupancy with the dose rate measured by the diamonds of the radiation monitor and beam-abort system. The effects of radiation damage are starting and in good agreement with our expectations. So far, no harmful impact due to the radiation damage on the detector performance has been observed. [ABSTRACT FROM AUTHOR]

The Belle II experiment located at KEK, Japan takes data from asymmetric e + e − collision provided by the SuperKEKB accelerator. The Silicon Vertex Detector (SVD), which is part of the Belle II Vertex Detector (VXD), has been operating smoothly and reliably since the start of data taking in March 2019. In this article, we report on the performance of the SVD in terms of the large signal-to-noise ratio, the good hit position resolution as well as the good hit-time resolution. New algorithms based on hit-time information are under development to improve robustness of tracking performance within the anticipated high background environment. The Background situation of the SVD has been constantly monitored and no degradation in performance is observed so far. To investigate the SVD performance at high luminosity runs in the future, simulation as well as an irradiation campaign are launched and their results are summarized. During the first long shutdown of the Belle II experiment, which starts from June 2022, the VXD has been refurbished with a new two-layer DEPFET pixel detector located inside the SVD. All the delicate phases of the disassembly, re-assembly and installation of the new VXD have been successfully completed. The new VXD commissioning phase began in Sept 2023 to get ready for beam operation starting in early 2024. [ABSTRACT FROM AUTHOR]

Abstract: The fluorescence quenching behaviour of naphthols by copper ion has been studied in different concentration of anionic sodium lauryl sulphate micelle. Various quenching processes have been analyzed to explain the quenching efficiency. The quenching behaviour of naphthols and naphtholates explained by a biphasic model consisting of two phases i.e.(a) quenching spheres containing the excited fluorophores and the quenchers resulting in transient component (for ROH*) and (b) the bulk phase where quenching is dynamic or diffusional (for RO¯*). The probable number of quenchers present in the quenching sphere of action has been calculated. [ABSTRACT FROM AUTHOR]

This paper describes the muon identification method and its performance in the Belle experiment at KEKB. Muon and hadron likelihood are calculated for each track using its range and transverse scattering in the KL-and-muon detector (KLM). We apply a cut on the normalized muon likelihood Lμ to identify the track as a muon. Above the detection threshold of 0.6 GeV/c, the measured muon detection efficiency and pion fake rate are approximately constant for momenta greater than 1.0 and 1.5 GeV/c, respectively. Between 1.0 and 3.0 GeV/c, the averaged muon detection efficiency is 89% and the pion fake rate per track is 1.4% over the KLM acceptance, using the standard selection criterion Lμ>0.9. [Copyright &y& Elsevier]

The "chip-on-sensor" concept of this detector minimizes the distance of the signal propagation from the double-sided silicon detector strips to the readout chips and thus reduces noise from strip capacitance. One half of the detector is built, the second half is being assembled at the time of writing. Prototypes have been tested in several test beams as well as in the so-called Phase 2 setup inside the detector structure. First results from a commissioning run of the Belle-II prototype SVD detector are presented. The measured signal-to-noise and timing performance are found to be according to design specifications. • The Belle-II Silicon Vertex Detector is based on a "chip-on-sensor" concept. • One half of the detector is built, the second half is being assembled. • Prototypes have been tested in a commissioning run inside the detector structure. • The measured SNR and hit time are found to be according to design specifications. [ABSTRACT FROM AUTHOR]

The Belle II experiment at the asymmetric SuperKEKB collider in Japan will operate at an instantaneous luminosity approximately 50 times greater than its predecessor (Belle). The central feature of the experiment is a vertex detector comprising two layers of pixelated silicon detectors (PXD) and four layers of double-sided silicon microstrip detectors (SVD). One of the key measurements for Belle II is CP violation asymmetry in the decays of beauty and charm hadrons, which hinges on a precise charged-track vertex determination and low-momentum track measurement. Towards this goal, a proper assembly of the SVD components with precise alignment ought to be performed and the geometrical tolerances should be checked to fall within the design limits. We present an overview of the assembly procedure that is being followed, which includes the precision gluing of the SVD module components, wire-bonding of the various electrical components, and precision 3D coordinate measurements of the final SVD modules. Finally, some results from the latest test-beam are reported. [ABSTRACT FROM AUTHOR]

The Belle II Experiment at the High Energy Accelerator Research Organization (KEK) in Tsukuba, Japan, will explore the asymmetry between matter and antimatter and search for new physics beyond the standard model. 172 double-sided silicon strip detectors are arranged cylindrically in four layers around the collision point to be part of a system which measures the tracks of the collision products of electrons and positrons. A total of 1748 radiation-hard APV25 chips read out 128 silicon strips each and send the analog signals by time-division multiplexing out of the radiation zone to 48 Flash Analog Digital Converter Modules (FADC). Each of them applies processing to the data; for example, it uses a digital finite impulse response filter to compensate line signal distortions, and it extracts the peak timing and amplitude from a set of several data points for each hit, using a neural network. We present an overview of the SVD data readout system, along with front-end electronics, cabling, power supplies and data processing. [ABSTRACT FROM AUTHOR]

The Belle II experiment is taking data at the asymmetric SuperKEKB collider (KEK, Japan), which operates at the Υ (4 S) resonance. The vertex detector is composed of an inner two-layer pixel detector (PXD) and the silicon vertex detector (SVD), made of four layers of double-sided silicon strip detectors. A deep knowledge of the system has been gained since the start of operations in 2019 by assessing the high-quality and stable reconstruction performance of the detector. The very high hit efficiency and large signal-to-noise ratio are monitored via online data-quality plots. The good cluster-position resolution is estimated using the unbiased residual with respect to the track, and it is in reasonable agreement with the expectations. The SVD dose is estimated by the correlation of the SVD occupancy with the dose measured by the diamond sensors of the radiation-monitoring and beam-abort system. First radiation damage effects are measured on the sensor current and strip noise are shown not to affect the performance. Six samples of the shaped particle signal are recorded utilizing the multi-peak mode of the APV25 front-end chip and used to determine the hit timing with a precision of 2 to 3 ns. Recently a method to compute the time of collision from SVD hit time information has been implemented and verified with simulations and on data. [ABSTRACT FROM AUTHOR]

A silicon vertex detector (SVD) for the Belle-II experiment comprises four layers of double-sided silicon strip detectors (DSSDs), assembled in a ladder-like structure. Each ladder module of the outermost SVD layer has four rectangular and one trapezoidal DSSDs supported by two carbon-fiber ribs. In order to achieve a good signal-to-noise ratio and minimize material budget, a novel chip-on-sensor “Origami” method has been employed for the three rectangular sensors that are sandwiched between the backward rectangular and forward (slanted) trapezoidal sensors. This paper describes the bonding procedures developed for making electrical connections between sensors and signal fan-out flex circuits (i.e., pitch adapters), and between pitch adapters and readout chips as well as the results in terms of the achieved bonding quality and pull force. [ABSTRACT FROM AUTHOR]

The Belle II experiment at the SuperKEKB collider in Japan is designed to indirectly probe new physics using approximately 50 times the data recorded by its predecessor. An accurate determination of the decay-point position of subatomic particles such as beauty and charm hadrons as well as a precise measurement of low-momentum charged particles will play a key role in this pursuit. These will be accomplished by an inner tracking device comprising two layers of pixelated silicon detector and four layers of silicon vertex detector based on double-sided microstrip sensors. We describe herein the design, prototyping and construction efforts of the Belle-II silicon vertex detector. [ABSTRACT FROM AUTHOR]

Since the start of data taking in spring 2019 at the SuperKEKB collider (KEK, Japan) the Belle II Silicon Vertex Detector (SVD) has been operating reliably and with high efficiency, while providing high quality data: high signal-to-noise ratio, greater than 99% hit efficiency, and precise spatial resolution. These attributes, combined with stability over time, result in good tracking efficiency. Currently the occupancy, dominated by beam-background hits, is quite low (about 0.5 % in the innermost layer), causing no problems to the SVD data reconstruction. In view of the operation at higher luminosity foreseen in the next years, specific strategies aiming to preserve the tracking performance have been developed and tested on data. The time stability of the trigger allows reducing sampling of the strip-amplifier waveform. The good hit-time resolution can be exploited to further improve the robustness against the higher level of beam background. First effects of radiation damage on strip noise, sensor currents and depletion voltage have been measured: they do not have any detrimental effect on the performance of the detector. Furthermore, no damage to the SVD is observed after sudden and intense bursts of radiation due to beam losses. [ABSTRACT FROM AUTHOR]

The silicon vertex detector of the Belle II experiment, structured in a lantern shape, consists of four layers of ladders, fabricated from two to five silicon sensors. The APV25 readout ASIC chips are mounted on one side of the ladder to minimize the signal path for reducing the capacitive noise; signals from the sensor backside are transmitted to the chip by bent flexible fan-out circuits. The ladder is assembled using several dedicated jigs. Sensor motion on the jig is minimized by vacuum chucking. The gluing procedure provides such a rigid foundation that later leads to the desired wire bonding performance. The full ladder with electrically functional sensors is consistently completed with a fully developed assembly procedure, and its sensor offsets from the design values are found to be less than 200 μm. The potential functionality of the ladder is also demonstrated by the radioactive source test. [ABSTRACT FROM AUTHOR]

The Silicon Vertex Detector (SVD), with its four double-sided silicon strip sensor layers, is one of the two vertex sub-detectors of Belle II operating at SuperKEKB collider (KEK, Japan). Since 2019 and the start of the data taking, the SVD has demonstrated a reliable and highly efficient operation, even running in an environment with harsh beam backgrounds that are induced by the world's highest instantaneous luminosity. In order to provide the best quality track reconstruction with an efficient pattern recognition and track fit, and to correctly propagate the uncertainty on the hit's position to the track parameters, it is crucial to precisely estimate the resolution of the cluster position measurement. Several methods for estimating the position resolution directly from the data will be discussed. [ABSTRACT FROM AUTHOR]

The Silicon Vertex Detector (SVD) is a part of the vertex detector in the Belle II experiment at the SuperKEKB collider (KEK, Japan). Since the start of data taking in spring 2019, the SVD has been operating stably and reliably with a high signal-to-noise ratio and hit efficiency, achieving good spatial resolution and high track reconstruction efficiency. The hit occupancy, which mostly comes from the beam-related background, is currently about 0.5% in the innermost layer, causing no impact on the SVD performance. In anticipation of the operation at higher luminosity in the following years, two strategies to sustain the tracking performance in future high beam background conditions have been developed and tested on data. One is to reduce the number of signal waveform samples to decrease dead time, data size, and occupancy. The other is to utilize the good hit-time resolution to reject the beam background hits. We also measured the radiation effects on the full depletion voltage, sensor current, and strip noise caused during the first two and a half years of operation. The results show no detrimental effect on the SVD performance. [ABSTRACT FROM AUTHOR]

Belle II is the next generation B Factory experiment operating at the SuperKEKB accelerator complex at KEK in Tsukuba, Japan. It is expected to collect 50 ab − 1 of data, with a target instantaneous luminosity of 6.5 × 10 35 cm − 2 s − 1 , which is about 30 times larger than its predecessor, Belle. In view of the ever increasing Belle II data sample, accurate simulation of the detector is growing in importance. This poses a challenging task of compromising between the realistic modeling of the response of individual detector components and reasonable performance in terms of CPU time of the simulation. In this paper we describe the simulation of the silicon vertex detector, its performance against collision data and optimization. [ABSTRACT FROM AUTHOR]

The safe disposal and utilisation of coal fly ash (CFA) for value addition are still major problems worldwide. Al 2 O 3 is a major valued material associated with it. Till date no methods are available to treat CFA for recovering its valued materials. Leaching of alumina from CFA in an economical way is very difficult, which either requires higher chemical consumption or application of stringent reaction conditions such as high temperature and pressure. In this paper a simple alternative method has been attempted to dissolve alumina from CFA. Addition of fluoride ion as HF improved the acid leaching performance of fly ash to a large extent. XRD data showed mullite, the alumina bearing phase, as the major phase which gets dissolved during leaching operation. A standard procedure for the precipitation of alumina can be employed after the leached solution is obtained. [ABSTRACT FROM AUTHOR]

The Belle II experiment at the SuperKEKB asymmetric e + e − collider in Japan will operate at a luminosity approximately 50 times larger than its predecessor (Belle). At its heart lies a six-layer vertex detector comprising two layers of pixelated silicon detectors (PXD) and four layers of double-sided silicon microstrip detectors (SVD). One of the key measurements for Belle II is time-dependent CP violation asymmetry, which hinges on a precise charged-track vertex determination. Towards this goal, a proper assembly of the SVD components with precise alignment ought to be performed and the geometrical tolerances should be checked to fall within the design limits. We present an overview of the assembly procedure that is being followed, which includes the precision gluing of the SVD module components, wire-bonding of the various electrical components, and precision three dimensional coordinate measurements of the jigs used in assembly as well as of the final SVD modules. [ABSTRACT FROM AUTHOR]

The Belle-II VerteX Detector (VXD) has been designed to improve the performances with respect to Belle and to cope with an unprecedented luminosity of 8 × 10 35 cm − 2 s − 1 achievable by the SuperKEKB. Special care is needed to monitor both the radiation dose accumulated throughout the life of the experiment and the instantaneous radiation rate, in order to be able to promptly react to sudden spikes for the purpose of protecting the detectors. A radiation monitoring and beam abort system based on single-crystal diamond sensors is now under an active development for the VXD. The sensors will be placed in several key positions in the vicinity of the interaction region. The severe space limitations require a challenging remote readout of the sensors. [ABSTRACT FROM AUTHOR]

Abstract: The influence of solvent polarity on the electronic transition of four different N-hexadecyl styrylpyridinium dyes has been investigated in 15 solvents. The E T(30) scale has been used to propose a quantitative approach towards the relative stability of the electronic ground and excited state species. The extents of contribution of dipolar aprotic solvents towards the solvation of the excited species have been determined to be 42–48% for some of the dyes. Instead of a steady solvatochromism, all the dyes suffer a reversal in solvatochromism. The transitions of the solvatochromism, referred to as solvatochromic switches, are found to be at E T(30) values of ∼50 for methyl and N,N-dimethylamino substituted dyes while at 37.6 for hydroxyl substituted dye and ∼45 for 4-(1-methyl-2-phenylethenyl) pyridinium dye. A reversal in the trend of solvent effect in the later dye corresponding to 4-(4-methyl styryl)pyridinium dye has been attributed to an analogy of series and parallel electron flow. [Copyright &y& Elsevier]

The Belle II experiment aims to accumulate 50 ab−1 of e + e − collision data at the SuperKEKB asymmetric energy collider (Tsukuba, Japan). The first physics data using all Belle II detectors were taken in spring 2019. In the vast physics program of the Belle II experiment, the vertex detector plays a crucial role for the determination of the B -meson decay vertices. It consists of two inner layers of pixelated silicon detectors and four outer layers of double-sided silicon strip detectors (SVD). To achieve a design luminosity of 8 × 1 0 35 cm − 2 s − 1 , 40 times higher than the recorded luminosity of its predecessor, the SuperKEKB collider squeezes the beams to a vertical size of 50 nm ("nano-beam scheme") and doubles the beam currents. Therefore, the detectors are required to tolerate intense beam induced background due to the very high luminosity. During the 2019 spring run we measured the occupancy rate in the SVD to estimate the level of the beam induced background. With the low initial luminosity, the observed beam induced background mostly originated from Touschek processes and beam-gas scattering within individual beams. Since these different background contributions depend differently on accelerator conditions, such as the beam current, beam size and pressure, they can be disentangled. We estimate the background rate of each contribution and compare them with simulated ones. The results enable us to predict the background levels at increased beam currents and luminosity in the coming years. They also hint at background mitigation measures for running at higher luminosity. In this proceeding we present the results of our study of the beam induced background in the SVD and the prospects for future operation. [ABSTRACT FROM AUTHOR]

The Belle II experiment at the SuperKEKB collider of KEK (Japan) started recording physics data in spring 2019 with all its subdetectors installed and with the goal of accumulating 50 ab−1 of e + e − collision events at the unprecedented instantaneous luminosity of 8 × 1 0 35 cm − 2 s − 1 , about 40 times larger than its predecessor. The Belle II vertex detector plays a crucial role in the broad Belle II physics program, especially for time-dependent CP measurements. It consists of two layers of DEPFET-based pixels and four layers of double-sided silicon strip detectors (SVD). The experience gained from the first period of SVD operation can be summarized as smooth and reliable running of the detector, with high stability of noise levels and calibration parameters obtained from local calibration runs. No major problem has been experienced. The detector even survived a few serious radiation accidents in which the beam was lost due to failure in the machine focusing quadrupoles without any notable damage. The SVD performance were carefully studied with these first physics data. The SVD showed excellent hit and tracking efficiency. Moreover, cluster energy and signal to noise ratio as well as the hit time and spatial resolutions measured on data showed a fair agreement with the expected performance. • Belle II silicon vertex detector operated during the first year of the experiment. • All sensors worked with stable and excellent hit efficiencies above 99 %. • Signal-to-noise ratios between 15 and 30, cluster time resolution better than 3 ns. • First effects of irradiation visible in leakage currents. [ABSTRACT FROM AUTHOR]

This paper shows the hardware and the procedure utilized to test all components of the readout system (cables, FADC boards, junction boards) of the Belle II Silicon Vertex Detector after the series production. For the FADC board special testing hardware and firmware were designed and created to check all digital and analog inputs and outputs as well as all data interconnections on the board. The main FPGA on the FADC board generates digital signals which are converted to periodic analog differential alternating voltages up to 40 MHz on the FADC board tester, which then are fed into the analog inputs of the FADC board. Histograms and scans of the samples are recorded by using random equivalent-time sampling or sequential equivalent-time sampling, allowing to characterize the behavior of the system with a much higher bandwidth than the ADCs could do with conventional measurements. Small changes of parameters of the assembly (like using a cable of different length) lead to significant changes of the measured values, creating a sensitive testing instrument. The shapes of the distributions are analyzed and compared to references by software which then decides if a test is passed or not. The commissioning setup of the whole readout chain, with all the final components including the final detector, has been tested in three phases. The respective graphs of the signal-to-noise ratios of the strips of a detector module and histograms of the noise development of the whole detector show very high consistency of the SVD readout system. [ABSTRACT FROM AUTHOR]

The Belle II Silicon Vertex Detector (SVD) was installed recently and has been prepared for physics run at SuperKEKB factory, Tsukuba, Japan. For a reliable operation and data taking of the SVD, a sophisticated and robust run and slow control system has been implemented, which utilizes the Experimental Physics and Industrial Control System (EPICS) framework. EPICS uses client/server and publish/subscribe techniques to communicate between the various sub-systems and computers. The information exchange between the different pieces of software and computers is done by process variables (PVs). These PVs are provided by input/output controllers (IOCs), which communicate and interface with the hardware components. The Belle II SVD slow and run control comprises five groups of subsystems, which are SVD DAQ controller, Flash ADC controller, environmental monitors and interlocks, power supplies and EPICS infrastructure services. In this paper we describe the tasks and the implementation of the individual sub-systems, the interaction between them and the global Belle II run and slow control as well as the first experience from commissioning and initial operation of the SuperKEKB accelerator. [ABSTRACT FROM AUTHOR]

The Belle II experiment at the SuperKEKB collider of KEK (Japan) will accumulate 50 ab−1 of e+e- collision data at an unprecedented instantaneous luminosity of 8 ⋅ 1035 cm−2s−1, about 40 times larger than its predecessor. The Belle II vertex detector plays a crucial role in the rich Belle II physics program, especially for time-dependent measurements. It consists of two layers of DEPFET-based pixels and four layers of double sided silicon strip sensors (SVD detector). We report here results of the standalone commissioning of the SVD and highlights from the first cosmic runs acquired in Belle II. We also report on reconstruction performances of a reduced-scale version of the SVD operated during the accelerator commissioning in 2018. [ABSTRACT FROM AUTHOR]