Study on the large position sensitive detector

A large position sensitive detector, in which the charge division technique is used, with a single wire anode proportional counter is developed. The sensitive area of the detector is 1200 x 60 mm2. The anode of the detector is NiCr wire with 10 μm in diameter and 12 Ω/mm of its resistance. The cathodes of the detector are single side aluminized Mylar films and the thickness 12.5 μm. The detector works under the condition of flushing the mixed gas of 70% Ar + 30% CH4 with one atmosphere. In order to test the detector a 241Am alpha source (about 5 MeV) is put on the collimator. The collimator can freely and accurately move along the detector window. Along the direction of anode wire, measurement is performed in the distance of every 6 cm. The total is 19 measuring points. The average intrinsic position resolution (FWHM) is about 0.6 mm, and the integral nonlinearity is better than 0.2%. This detector has been installed on the detector system of Q3D magnetic spectrometer and will be tested on the tandem accelerator with ion beam