New the Design and Measurements of the Portable Cosmic Ray Muons Detector (CRMD) for an Observatory

Polatoğlu A., Yeşilyaprak C., Kaya M., Shameoni Niaei M., Er H.

Universal Journal of Physics and Application , cilt.17, sa.4, ss.33-42, 2023 (Hakemli Dergi)

Özet

Cosmic Rays (CR), which provide crucial insights into the structure and evolution of the universe and astronomical phenomena such as supernovae, hold significant importance in the realms of physics and astrophysics. Simultaneously, CRs pose a challenge in astronomical observations due to their generation of hot pixels, necessitating the need for their fluxes to be accurately determined and eliminated from charge-coupled device (CCD) images. To address this, it is essential to measure the cosmic ray background at large observatories. In response, we developed a cosmic-ray muon detector utilizing scintillation technology, employing a plastic scintillator and a photomultiplier tube. We utilized the DRS4 Evaluation Board ver. 5.1 read-out system for signal reception and processing. Our measurements were conducted at the ATA50 Telescope on the Atatürk University campus and at the site of Turkey’s largest telescope, the Eastern Anatolia Observatory (DAG), using our custom-designed cosmic ray muon detector (CRMD). For the calculation of cosmic ray flux, we applied the Time of Flight (TOF) method, which calculates the flight time of cosmic rays passing through scintillators positioned vertically on a shelf. Data analysis was conducted using our Python code and ROOT programs. Cosmic ray-muon measurements involved placing the detector at various zenith angles. At the DAG site (elevation 3170 m), we observed a cosmic ray flux of 0.0450 cm-2s-1sr-1. Conversely, at the lower altitude ATA50 Telescope site (elevation 1855 m), the flux was measured at 0.0235 cm-2s-1sr-1. Notably, a 1-meter thick concrete structure was found to reduce cosmic muon measurements by 56%. Furthermore, the flux values obtained at 30°, 45°, 60°, 75° angles showed compatibility with theoretical predictions and were compared with existing literature values. These findings demonstrate the reliability, stability, and cost effectiveness of our custom-designed detector.