Re: normalizations to UA1

• Previous message: Joe Natowitz: "normalizations to UA1"
• In reply to: Joe Natowitz: "normalizations to UA1"
• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] [ attachment ]

Hi Joe,
I think that Claus will have to answer the details on this.  I have 
only seen a plot which shows
UA1 and STAR both corrected to our acceptance, and they looked the same.
-Ian
On torsdag, jul 10, 2003, at 23:15 Europe/Copenhagen, Joe Natowitz 
wrote:

>  
> I have been talking to Carl Gagliardi here at TAMU. He is part of 
> STAR. He raised a question about the following statement in the latest 
> PRL regarding normalizations.
>
> "Also shown in the figure is our
> measured spectrum from d+Au collisions. The reference
> is from p + ¯p collisions measured in the range
> || < 2.5 by the UA1 experiment at CERN [13]. To
> compare with our spectra we apply a pT and dependent
> correction estimated using the HIJING (v.
> 1.383) code [14], which reproduces the main features
> of p + p collisions well. We have compared our corrected
> spectrum at = 0 with the ps=200 GeV p+p
> distribution recently measured by the STAR collaboration
> [15] and find excellent agreement.  "
>  
>
> Carl is surprised because in ArXiv / 0305015 - they point out the 
> following.
>
> "The charged hadron invariant cross section
> has been measured in ¯p + p collisions at ps=200 GeV
> [23]. (THIS IS UA1-our reference 15) The p+p cross section reported 
> here is smaller by a
> factor of 0.82 ± 0.18, approximately independent of pT ,
> where the uncertainty includes the two spectrum normalizations
> and the correction for different acceptances [3].
> The difference is due in large part to differing NSD cross
> section, which is 35 ± 1 mb in [23] but is measured here
> to be 30.9 ± 3.5 mb."
>
> He believes that comparison of our results with STAR on a per event 
> basis might show agreement but that the cross section from STAR is 
> different from UA1 and shifts the normalization. This is different 
> from the Kopeliovich question.
>
>  
>
>
> Comments ?
>
>
> Joe
>  
> ---
> Outgoing mail is certified Virus Free.
> Checked by AVG anti-virus system (http://www.grisoft.com).
> Version: 6.0.495 / Virus Database: 294 - Release Date: 6/30/2003

• Next message: Ian Bearden: "High Pt"
• Previous message: Joe Natowitz: "normalizations to UA1"
• In reply to: Joe Natowitz: "normalizations to UA1"
• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] [ attachment ]

This archive was generated by hypermail 2.1.5 : Fri Jul 11 2003 - 04:35:41 EDT