Cf252 NaI detector test. 12 Apr 2012

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041212

• NaI detector,
• 300 mV threshold on gate channel
• signal ADC4
• -1030V at the beginning
• -1055V at the end of run

Run #	source	shielding	cnts	rate	Comments
2775	Co-60 away from NaI	2" Pb around, no front shielding	133,884
2776	bkgd	2" Pb around, no front shielding	7,289
2777	Co-60 infront of NaI	2" Pb around, no front shielding	313,427		1.2 and 1.4 MeV peaks, small peak around 4.3 MeV Calibration 1.4 MeV/575 cnls = 0.00243 MeV/cnl
2778	bkgd	2" Pb around, no front	15,822	41.75 Hz
2779	bkgd	all around 2" Pb around	8,566	15.74 Hz	good area around 2000-3800 channels
2780	Cf252	all around 2" Pb around		12 kHz	Cf252 just in front of NaI
2781	Cf252	all around 2" Pb around		5.4 kHz	Cf252 about 15 cm away from NaI
2782	Cf252	all around 2" Pb around	607,790	1.1 kHz	Cf252 17" away from NaI
2784	Cf252	all around 2" Pb around	1,372,745	1,142 Hz	20 min run. No shielding in front
2785	Cf252	all around 2" Pb around	153,508	129.5 Hz	20 min run. 2" Pb just after Cf252
2787	Cf252	all around 2" Pb around	1,231,537	1,024 Hz	20 min run. 2" Borated Poly just after Cf252
2788	Cf252	all around 2" Pb around	1,225,232	1,020 Hz	20 min run. 2" Unborated Poly just after Cf252
2790	Cf252	all around 2" Pb around	132,067	111.6 Hz	20 min run. 2" Pb, 2" Borated Poly just after Cf252
2791	Cf252	all around 2" Pb around	108,603	89.6 Hz	20 min run. 4" Pb just after Cf252
2792	bkgd	all around 2" Pb around	45,904	25.04 Hz	20 min run. background checking

• rise time of NaI 50 ns
• decay time of NaI 3 us

• run 2784: Cf252 no shielding infront. 1,372,745 events

• run 2787: Cf252 2" Borated Poly infront. 1,231,537 events

• run 2788: Cf252 2" Unborated Poly infront. 1,225,232 events

• run 2792: background checking. 45,904 events

• run 2785: Cf252 2" Pb infront. 153,508 events

• run 2790: Cf252 2" Pb + 2" Borated Poly infront. 132,067 events

• run 2791: Cf252 4" Pb infront. 108,603 events

041312

• NaI detector,
• 300 mV threshold on gate channel
• signal ADC4
• -1036V switched to modern power supply

Run #	source	cnts	rate	Comments
2793	bkg			shielding: detector -> 2" Pb around -> 2" Poly around V = -1014 V
2794	Cf252		1.24 Hz	new power supply N471 CAEN, -1035V Cf252 17 inch away from detector, DAQ crashed shielding: Al around the NaI -> borated shielding (not infront)
2795	Cf252	55,458	88.23 Hz	4" Pb infront of Cf252 + Al around and inside the shilding 10 min
2796	Cf252	130,122	79.23 Hz	27 min, looking for (n,gamma) capture effect, 10B: 4.44 MeV (100%) geometry: Cf252 -> 5" Pb -> bored Poly (small brick) -> 2" Al ----> NaI
2797	Cf252	80,763	81.79 Hz	geometry: Cf252 -> 5" Pb -> bored Poly (whole) -> 2" Al ----> NaI
2798	Cf252	134,725	95.38 Hz	geometry: no Boron but Al is still in 23 min
2799	bkg	21,6941	37.86 Hz	background long 108 min run detector + 2" Pb around (except on the top of detector was 2" Al) + 2" Poly around
2800	bkg			background long run detector + 2" Pb around + 4" Poly borated and unborated around, no Al inside

• run 2799

• run 2800