12-16 September 2005
University of Liverpool
Europe/Zurich timezone

The novel multi-collimator using BP-1 glass and an application for X-ray CCDs

Sep 15, 2005, 5:15 PM
University of Liverpool

University of Liverpool

Greenbank Conference Park
Contributed Talk Novel Photon Detection Systems S13 : Applications in Space Science


Dr Junko Hiraga (JAXA/ISIS, Kanagawa, Japan)


Charge-coupled devices (CCDs) are widely used in soft X-ray Astronomy as a focal plane detector which has a capability both of good spatial resolution and good energy resolution up to 10 keV, simultaneously. For the future X-ray space mission, the thick CCDs are developed to improve the quantum e±ciency of high energy X-rays beyond 10 keV. A mesh experiment has been, so far, the only practical technique to study CCD response with subpixel resolution. The mesh technique has revealed the X-ray response within a pixel for various types of CCDs (see e.g., Hiraga et al. 2001[1]). Hiraga et al. [2] developed this technique to directly measure the final charge cloud shape. However the mesh experiment is valid for X-rays only when they can pass through the mesh at a hole. The mesh of the out-of-hole position must be opaque for X-rays. Employing the gold mesh of about 13 µm thickness that is the thickest one in current production, the e®ective energy range was thought to have an upper limit of 7 keV. This fact has prevented us to measure the charge cloud shape for higher energy X-rays. We have proposed the new method to produce the novel multi- collimator using Barium Phosphate (BP-1) glass which has originally developed as a solid state track detectors (Wang et al. 1988[3]). The BP-1 collimator enables us to determine the interaction position of each X-ray photon much precisely than the CCD pixel size ( 10µm in general) up to 20 keV Xrays. We performed the first experiment of this project in which 80- 100MeV/nucleon of Xe beam was irradiated to the 1.3mm-thick-BP-1 glass. After the etching process, we obtained the first prototype of BP-1 collimator. It has lots of tapered pinholes which are randomly distributed, » 104 holes cm−2 with high aspect ratio. In this conference, we will report the novel collimator and the results of an application to the X-ray CCDs.

Primary author

Dr Junko Hiraga (JAXA/ISIS, Kanagawa, Japan)

Presentation materials