Setup of Gain Monitoring Systemwith Mr. Uozumi

Kobe Univ.

Hiroko Ikeda

18,May 2007

STATUS・ Mr.Uozumi brought 3flat cables (with MPPC

s),

a circuit for readout, a LED driver, and LEDs

(high-functional, and UV).

・ The LED driver, and one of the flat cables had

been broken.

STATUS・ Signal from flat cable is integrated by ADC,

and number of photons enter each strip is

calculated.

MPPCs(1600 pixels)

Acryl Frame

Scintillator strip(1 x 4.5 x 0.3 cm)

To trigger reflection, put reflective material on strips.

Then, set the acrylic plate covered by the same material on it.

And, shade all from light with black sheet.

ADC

AMP

PC

EFFORTⅠ　 At first, there was only one hole on the

reflective

material.

Signal was very small, so, in order to observe

larger one, cut holes on the center of each strip.

Small change observed.

Signal was still small.

To see much larger signal, make one of holes

bigger roughly, and other 2 holes a single one.

EFFORTⅡ

Obvious change observed.

Measurement is ongoing in this circumstance now.

RESULTSSize and position of hole

Distance from LED

At least 5 photons reach each strip now.

effect on amount of light

OUTLOOK・ Make much more stable structure to get recreativity.

・ Use multi channel amp .

・ Study and compare about material and characteristic of

acrylic plate.

・ Examine which effects more on amount of light size or

distance of holes

ー if size, need to consider effect of cross-talk

・ Reduce LED noise.