offsets

dth_hs correction 03/08/06

The offset dth_hs had a sign error and is corrected in the table below. Previous results were put in with the wrong sign into the analyzer. The problem was because my kumac (h.kumac) applied the offset to hsyptar while the analyzer applied the offset to hpcentral. These changes, while equal in magnitude are opposite in sign.

Offset look-up table 03/08/06 (rev. 03/15/06)

The results in the Hee'p analysis:

Ebeam(GeV)	P hms(GeV)	TH hms(deg)	P sos(GeV)	TH sos(deg)	dE	dth_ss	dp_ss	dth_hs	dp_hs	dssxptar
2.038	-1.692	25.005	0.874	54.90	0.0	0.8	0.5	1.0	1.5	0.0036
5.012	4.116	18.70	-1.7227	50.00	0.0	-0.3	10.2	0.2	2.4	0.008
5.766	4.867	16.19	-1.6868	51.61	0.0	0.05	7.65	-0.05	0.8	0.0062
4.021	3.232	22.15	-1.588	50.00	0.0	0.0	1.9	0.8	2.15	0.0052

NB- dp_ss and dssxptar were parameterized, and so the actual offsets used in the replay are slightly different to this table. This parameterization can be found here, and the parameterized offsets are:

Ebeam(GeV)	P hms(GeV)	TH hms(deg)	P sos(GeV)	TH sos(deg)	dp_ss	dssxptar
2.038	-1.692	25.005	0.874	54.90	0.42	0.00368
5.012	4.116	18.70	-1.7227	50.00	10.51	0.00753
5.766	4.867	16.19	-1.6868	51.61	6.92	0.00674
4.021	3.232	22.15	-1.588	50.00	2.57	0.00533

The following offsets were used:

th_sos   dth_ss
>56.55 0.5
>53.26   0.8
>50.81   0.05
>49.20   -0.15
else        0.0

th_hms dth_hms
>26.43     0.5
>23.58     1.0
>20.43     0.8
>17.45     0.2
>14.94     -0.05
else           0.0

|P_hms| dp_hs
>5.25        1.1
>4.49        0.8
>3.67        2.4
>2.46        2.15
>0.92        1.5
else            1.1

The offsets are to be included as follows
         p_e = ssp*(1-dp_ss/1000.0)
         th_e = mysstheta-dth_ss/1000.0   [rad]
         p_p = hsp*(1-dp_hs/1000.0)
         th_p = myhstheta-dth_hs/1000.0   [rad]
         newE=e_beam*(1+dE/1000.0)
     newssxptar= ssxptar- dssxptar

Results 03/08/06

After inserting the offsets into replay, the heep runs were analyzed again and here are the positions of the peaks.
(link)
The peaks are very close to zero, with one setting having a 5 MeV difference from zero in the histogram of (W-Mprot). This difference is due to the parameterization of dp_ss, which was
-0.3844-0.01778*exp(x**3.3971) and plot here

However, this difference in dp_ss is not very important because the yields do not have a large dp_ss dependence.