EAS thermal neutron lateral and temporal distributions

Abstract: A noveltypeofEASarray(ProtoPRISMA-32)hasbeenconstructedonthebaseofNEVOD-DECORexperiment(MEPhI,Moscow)andisnowtakingdata.Itconsistsof32speciallydesignedscintillatoren-detectorsable to measure two main EAS components: hadrons (n) and electrons (e). First results on thermal neutronlateral as well as temporal distributions are presented. Obtained exponential neutron lateral distributions areconsistent with that expected for normal hadronproductionwith exponentialtransverse momentumdistribution.As there are no other experimental data on thermal neutron distributions and so, to compare results with othermeasurements, we additionally obtained electron lateral distribution function (using the same detectors) andcompared it with NKG - function. Recorded neutron temporal distributions are very close to that obtained withdata of our previousprototypes. Keywords: EAS, neutrons,en-detector,distributions 1 Introduction An idea of a noveltypeof EAS arrayproposedforthe firsttime in 2001 [1] was developed later [2, 3] to the PRIS-MA(PRImarySpectrumMeasurementArray)project.Themain feature of the array is the ability to measure themainEAScomponent-hadrons,throughthemeasurementof secondary thermal neutrons produced by these hadron-s. Special inorganic scintillator detector (en-detector) hasbeen developed for this purpose. The main feature of thedetector is sensitivity to two EAS components: hadrons -the main one and electrons - the most numerous one. Aprototypeof such arrayconsisting of 32 en-detectors(Pro-toPRISMA) is running now in Moscow on a the base ofthe NEVOD-DECOR experiment (MEPhI). It started inFebruary2012.Detailsoftheen-detectordesignandoftheProtoPRISMA array can be foundelsewhere [4, 5].