Cosmic ray flux and lockdown due to COVID-19 in Kolkata – Any correlation?

Cosmic ray muon flux is measured by the coincidence technique using plastic scintillation detectors in High Energy Physics detector laboratory at Bose Institute, Kolkata. Due to COVID19 outbreak and nationwide complete lockdown, was closed from end of March 2020 till May 2020. After although city not its normal state, we still were able take data on some days. The lockdown imposed a strict restriction transport service other than emergency ones also most industries shut down around city. This has significant effect atmospheric conditions terms change concentration air pollutants. We have cosmic before after observe apparent if any due conditions. In this article, report Kolkata (22.58$^{\circ}$N 88.42$^{\circ}$E 11~m Above Sea Level) along with major pollutants present atmosphere lockdown.