[Olympus] Monday slides

[Axel Schmidt]

Hi Michael,

Let me try to answer your questions re: my slides:

> On Axel's slides:
> is the spread of the pile-up luminosity data points all statistical, or 
> are there drifts within runs or fills (e.g. the red and blue vertical 
> bands on slides 3/4?

The plotted error bars are purely statistical. 

We can clearly see some drifts which are not statistical. At the meeting, it was suggested that this might be caused by a drift in the peak position in the histograms. Barring that, I need to see if these drifts correlate with: 1) beam position, 2) dead-time percentage, 3) target temperature, i.e. any other effect we can think of and monitor.


> Do we have any idea what causes the wiggles in phi, and are the same 
> phi wiggles also responsible for the structures versus polar angle?

We have ideas, but no conclusive evidence, to the best of my knowledge. Errors in geometry could cause this, and these could be as diverse as some deformation of the wire chambers, or even sag in some individual wires. I think that magnetic field is unlikely, since the wiggles have the same direction regardless of lepton species.

Best regards,
Axel