The NEVOD-EAS array is now being installed at MEPhI to determine the sizes, directions of arrival, and positions of the axes of extensive air showers (EAS), different components of which are recorded by the detectors of the NEVOD experimental complex. The central part of the NEVOD-EAS array, which contains four clusters of scintillation detector stations designed to record a shower’s electron–photon component, was created and put into operation in 2015. A description of the shower array measuring system and the results from reconstructing extensive air showers recorded in the first 49-day series of experiments are presented.

In 2014, the creation of a new cluster type shower array NEVOD-EAS was started around the Cherenkov Water Detector NEVOD and coordinate detector DECOR. The shower array will allow to determine the size, axis position and arrival direction of EAS registered by these detectors. In 2015–2016, the NEVOD-EAS central part, including 4 clusters of scintillation detector stations located on an area of about 104 m2, was deployed and started operation. This article presents the description of the NEVOD-EAS arrangement, detecting elements and data acquisition system, as well as the first results on EAS detection.

A cluster type NEVOD-EAS setup is being constructed by the National Research Nuclear University MEPhI on the basis of the Unique Scientific Facility “Experimental Complex NEVOD”. The NEVODEAS setup is intended for the detection of extensive air showers (EASs) with energies in the region of the knee in the energy spectrum of primary cosmic rays (10 15 –10 17 eV). The key elements of the setup are 192 particle detectors for EAS electron–photon and muon components. These detectors are composed of NE102A organic scintillators and Philips XP3462 photomultiplier tubes enclosed in pyramidal steel cases. The techniques used to investigate the characteristics of scintillator plates, photomultiplier tubes, and NEVOD-EAS detectors, as well as the results of this investigation, are discussed. All measurements have been taken using special testing facilities and the precision URAGAN muon hodoscope, with which it is possible to comprehensively investigate the nonuniformity of light collection in the detector (the dependence of the detector response on the location of the passage of a charged particle through its operating volume).

A new cluster type shower array NEVOD-EAS is designed for estimating the size, axis position and arrival direction of extensive air showers registered by the Cherenkov water detector NEVOD and coordinate detector DECOR (Moscow, Russia). In 2015-2016, the central part of the array was deployed and started its operation. It includes 4 independent clusters of scintillation detector stations located around the NEVOD-DECOR experimental complex on the area of about $10^{4} m^{2}$. This article presents the results of studying amplitude and timing characteristics of the array clusters which are critical for EAS parameters reconstruction, as well as the examples of registered events.

A new setup for registration of the electromagnetic component of the EAS at the "knee" region of the energy spectrum of primary cosmic rays (PCR) is now under construction on the basis of the experimental complex NEVOD-DECOR (Moscow, Russia). The EAS array detecting system has a cluster organization. Clusters are located in the MEPhI campus. The specific features of the array registering system that provides particle detection, data acquisition, cluster synchronization and events selection are discussed. The results of counter characteristics study are also presented.

The NEVOD-EAS setup is designed for independent estimation of the EAS parameters recorded in the NEVOD-DECOR experiment in the region of the energy spectrum knee. The setup’s recording system is based on the clusters of scintillation detectors for the EAS electron-photon component, located on the territory of MEPhI. Characteristics of the shower array recording system that ensure detection, data acquisition and primary processing, and the time synchronization of clusters are discussed, along with results of studying the nonuniformity of NEVOD-EAS scintillation detector responses.