Tritium digital autoradiography with a Medipix2 hybrid silicon pixel detector

Dipartimento di Scienze Fisiche, Università di Napoli Federico II and INFN, Sezione di Napoli, Via Cinthia, I-80126 Napoli, Italy
Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment (Impact Factor: 1.14). 01/2004; DOI: 10.1016/j.nima.2003.09.027

ABSTRACT We report on the first measurements of 3H beta autoradiography obtained using a room temperature hybrid pixel detector, consisting of the Medipix2 single particle counting read-out chip bump-bonded to a 300 μm thick silicon pixel detector. This system has 256×256 square pixels of 55 μm pitch for a total sensitive area of 14×14 mm2. Each pixel contains a double threshold discriminator and a 13-bit counter. Using a detection threshold equivalent to less than 6 keV and a background count rate of 5×10−3 counts mm−2 s−1, with exposures up to several hours, real-time images have been obtained of tritium-labeled solution drops spotted on a thin mylar foil placed in contact with the continuous top electrode of the silicon detector, in open air condition.

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