Jan20-21, 2015


R49_* are a set of files corresponding to an overnight background measurement, with goal of detecting alphas
from uranium decay chain contaminants.

The settings of ASICs are attached as a screenshot. The low comparator thresholds are (see previous entry):
 nnaida#11= 0x16
 nnaida#12= 0x40 
 nnaida#13= 0x20
 nnaida#14= 0x16

For a significant fraction of the measurement, NNAIDA12 and NNAIDA13 were not generating good data. We 
didn't
invest much time in solving the issue, as it's recurrent problem with NNAIDA12, but it seems some ASICS went
back to normal behavior overnight.

Due to limited storage space, data in external drive (/media/data/TapeData/Test100/), and backued up 
temporarly
in Edinburhg (/Disk/ds-sopa-personal/aestrade/data/AIDA/).

A pulser walkthrough for this setting is available in runs R61-R65 (see next elog entry).



++ DATA ANALYSIS ++

A fraction of the runs (R49_1, R40_10-14) were analysed with the 'beta' version of the Root sort code for 
event
reconstruction (/homes/npg/AIDAsort/). The code creates events from data bits that fall within a window of
50usec, and included the additional requirement that the calibrated energy of each ADC hit should be E>1500 
keV.

Output from Root sort code saved here:

aestrade: AIDA $ pwd
/Disk/ds-sopa-personal/aestrade/rootfiles/AIDA
aestrade: AIDA $ ls R49_alpha_bckgr*
R49_alpha_bckgr_10_calib_log.txt  R49_alpha_bckgr_13_calib.root
R49_alpha_bckgr_10_calib.root     R49_alpha_bckgr_13_event_log.txt
R49_alpha_bckgr_10_event_log.txt  R49_alpha_bckgr_13_event.root
R49_alpha_bckgr_10_event.root     R49_alpha_bckgr_14_calib_log.txt
R49_alpha_bckgr_11_calib_log.txt  R49_alpha_bckgr_14_calib.root
R49_alpha_bckgr_11_calib.root     R49_alpha_bckgr_14_event_log.txt
R49_alpha_bckgr_11_event_log.txt  R49_alpha_bckgr_14_event.root
R49_alpha_bckgr_11_event.root     R49_alpha_bckgr1_calib_log.txt
R49_alpha_bckgr_12_calib_log.txt  R49_alpha_bckgr1_calib.root
R49_alpha_bckgr_12_calib.root     R49_alpha_bckgr1_event_log.txt
R49_alpha_bckgr_12_event_log.txt  R49_alpha_bckgr1_event.root
R49_alpha_bckgr_12_event.root     R49_alpha_bckgr1_sort_log.txt
R49_alpha_bckgr_13_calib_log.txt  R49_alpha_bckgr1_sort.root

A few plots from these data:

R49few_a_bckgrnd_multiplicity.png: Shows the multiplicity of reconstructed events. Peaks corresponding to
multiples of 64 are clear from pulser (64 ch/asic, although one FEE has some channels off so peaks shifted).
There is also peak at low multiplicity where gate to search for events can be placed. The events with very 
high
multiplicity indicate the time window used is too large, so we get random coincidences or high count from 
noisy
channels. The lower plots show how the energy sum increases linearly with the multiplicity of the event

R49few_a_bckgrnd_xy.png: Plots for the calculated mean strip for hits on each side (<x>: nnaida#11 and #12, 
<y>:
nnaida#13 and #14). The different plots have different condition applied. Top left only requires 
multiplicity on
x and y greater than zero (i.e., a hit for each side). The others require low multiplicity, or low spread of 
the
timestamp of the hits included (spread dts<10usec), and also mask out hits with x value of 18 or 101 (very 
high
count channels)

R49few_a_bckgrnd_dt_event.png: The difference of the time-stamp for hits with lowest and highest time-stamp
within each event. 50 usec is the event window considered (so highest possible value). Note that events with
multiplicity 2 (1 hit in x, and 1 hit in y) have almost exclusively a spread of very few clock cycles.

R49few_a_bckgrnd_EfEb.png: Energy front vs energy back spectra, with some of the conditions described above
(e.g. low multiplicity, or multi=2, low spread in time-stamp). All have hits with x=78 and 102 excluded. The
most clean spectra is top-right (one hit in x, one hit in y), but shows only a couple of hits with good 
energy
in both sides.