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Luminosity Monitoring and Asymmetries from 500 GeV running

Updated on Fri, 2010-02-05 17:12. Originally created by aliceb on 2009-05-27 15:31.

Introduction

We are interested in the agreement between the various scalers and local polarimeters when calculating luminosity asymmetries.  For example, we compare "square root asymmetries" calculated with the ZDC SMD to asymmetries from the BBC scalers. 

Our goal is to see if corrections to the luminosity as calculated from BBC coincidences are needed.  We apply CDF-style corrections for accidentals and multiple interactions, described here.  We find that applying these corrections gives generally better agreement between the ZDC SMD and the BBC scalers. 

Certain square root asymmetries contain terms that are proportinal to ANN or ALL.  We see some evidence for small ANN and ALL in both the transverse and longitudinal running, with stronger evidence for the longitudinal runs.

Results

A document describing the analysis is attached.

Update 22 July 2009

We discovered an error in Equation 19, we are working on analyzing again with this corrected.  Also we found on closer examination that, especially for transverse data, BBC scaler counts for some runs were strange.  We are studying this again as well.  A presentation with some updated results for one transverse and one longitudinal fill is attached.

 

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