Project

General

Profile

Kaon LT Meetings » mtg_23may11.txt

Garth Huber, 05/12/2023 03:35 PM

 
1
Richard:
2

    
3
Met with Carlos to discuss luminosity scan analysis differences.
4
Found Carlos was looking at ELREAL while Richard was looking at ELCEAN.
5
Results more consistent when both using ELREAL. 
6

    
7
Showed luminosity scan fits with error bars, but something still looks not
8
quite right. Will use root next (using python right now) to see if fit
9
parameters/uncertainties look more reasonable.
10

    
11
Discussed next replay for 2018/2019 data - after offsets determined.
12

    
13
Ali:
14

    
15
Grabbed latest BPM calibration info from wiki:
16
https://hallcweb.jlab.org/wiki/index.php/BPM_calibration_information
17

    
18
Had some impact on peak positions, but not large.
19

    
20
BPM calibrations: will use Feb. 2019 values since data were taken in March.
21
For all Fall 2018 data, will use 8/29/2018 values.
22

    
23
Showed raster-y tests (changing sign) - we had it right to start with.  Small
24
residual dependence on raster-y could be taken out by scaling the value of
25
raster-y.  This could have impact on other resonstructed quantities though
26
(xptar, ztar) so we should be cautious about doing this.
27
DG note: perhaps we could just scale the relevant xtar-delta matrix element?
28

    
29
Vijay:
30

    
31
Question: Will raster-y issue be addressed before next replay? Yes - it should
32
be.
33

    
34
HMS calorimeter efficiency: getting rather low efficiency using production data
35
(0.95). Cherenkov cut is pretty low though (0.65 npe).  Will re-do with
36
higher cut. Also will look at Heep data.
37

    
38
Nathan:
39

    
40
HMS Cherenkov calibration: fixed main issue from last week - was selecting wrong
41
timing peak.  Now calibrations look reasonable - but, more random variation than
42
one would like.  Julie suggests looking at 2 runs that have very different
43
calibration but were taken close together in time. Also, the fit range for
44
the single-photo electron peak might be too big.
45

    
46
Junaid:
47

    
48
HMS DC calibration.  Added multiplicity cut and drift distance spectra look
49
good now (residuals also look good, but I think they were fine before).
50
DC calibrations will be done for each HMS (Q2,W, epsilon) setting.
51

    
52
SHMS is next.
53

    
54
Question at end of meeting from Ali: After determining offsets from Heep data,
55
should they ne included in simc?  Yes - they represent real changes to the
56
spectrometer central angles and momenta which could impact average Q2, W, -t
57
etc.
(226-226/564)