The neck cut uses the neck tubes (ID 9901 and 9902) to look for neck events. It has three different selection methods. The first is to see if both neck tubes are present in an event. The second technique requires that one of the neck tubes is present in the event and that it has a high charge and is early. Early is defined by the neck tube being more than on offset before the average time of the PMT's in the lower hemisphere of the detector. The charge must be less than qmin or greater than qmax, for any of QHS, QHL or QLX. This cut has two modes for time and charge. The first uses raw ADC values, the second uses ECA times and pedestal subtracted charges. If using ECA times and they are not available, for instance PCA is in use, the neck cut will calculate ECA times for tubes if required. The final mode looks for pickup on the neck paddle card.
The constants for this cut are contained in FLTH 17.
*DO FLTH 17 -i(31I 6F 3I) #. FLTH: Neck Tube Cut
#.
19750101 0 20380517 03331900 6*0 #. Standard Database Header
19750101 0 20380517 03331900 16*0
#.
22 #. Mode =10*i+j
#. i: Time Mode =1 ADC values, =2 Full ECA times
#. j: Charge Mode =1 ADC values, =2 Pedestal subtracted charge
650. #. TAC diff, mode i=1
400. #. Charge min, mode j=1
1000. #. Charge max, mode j=1
68. #. Time diff, mode i=2
-100. #. min charge, mode j=2
600. #. Max charge, mode j=2
4 #. Number of tubes to fire on paddle card to id as pickup.
15 #. Minimum nhit
5000 #. Maximum nhit