Dear Jens Jorgen,
thanks for the quick reply. It seems to me that
your plot is wrong. Look at Fig 4 of PRC63 024901. For pbar/p=1
k-/k+ =1 of course. For pbar/p=0.4 k+/k-=1.17 implying k-/k+=0.85
not 0.74 as you show in your plot. I think it is important to
show our 130GeV data too and so that should be mentioned in the
text. While the errors on NA49's pbar/p are large they are
consistently larger than our results. By the way the AGS data in
my plot are for y=0.
Yours Michael
PS I will send you my ratios in tabul form. However I think that
my plot looks nicer than yours.
Quoting Jens Jørgen Gaardhøje <gardhoje@nbi.dk>:
> Hi Michael,
>
> Thanks for the plot. Claus and I brain stormed a bit his afternoon,
> prior to
> ypour message. ¨
>
> We fit the Brahms data at 200 and 130, the Na49 and the AGS
> data nicely with a functional: k-/k+= A (pbar/p)** B +C. This suggest a
> universal scaling of Kaon rations (hence mu_s) with P ratios (hence
> mu_B).
>
> I don't understand your comment about Beccatini being wrong. He has
> used
> full rapidity integrated info. Is Becattini wrong or is our plot wrong?
> Is
> the issue that in becattini's table different strange fugacities are
> used
> (gamma_s)? Our curve uses his values but with gamma_s =1 (i.e. no
> strangeness loss from the volume).
>
> We'll add a mu_b scale on the plot (fig.4) based on
> pbar/p=exp(-2mu_B/T).
>
> Could you send us the numbers and the best ref. for (our) NA44 data at
> SPS?
>
> We would appreciate if you could supply us with the absolute latest
> AMPT
> ratios, in a form ready to plug into a root macro.
>
> We should really announce this paper at the end of the week. There was
> significant interest for our data at the Gordon conf.
>
> cheers
> JJ
>
>
> ____________________________________________________________
> Jens Jørgen Gaardhøje, Assoc. Prof., Dr. Sc.
> Niels Bohr Institute, Blegdamsvej 17, 2100 Copenhagen, Denmark.
> Tlf: (+45) 35 32 53 09, secr. (+45) 35 32 52 09, Fax: (+45) 35 32 50
> 16.
> UNESCO Natl. Comm., secr. (+45) 33 92 52 16.
> Email: gardhoje@nbi.dk.
> ____________________________________________________________
>
>
> ----- Original Message -----
> From: "Michael Murray" <murray@cyclotronmail.tamu.edu>
> To: <brahms-l@bnl.gov>
> Sent: Tuesday, June 25, 2002 8:57 PM
> Subject: Re: Ratios Paper - Draft 2.2
>
>
> > Dear Claus and Jens Jorgen,
> > thanks for the new ratios draft. I think
> > that it is a great improvement. However I have some concerns
> > about Fig 4, I have attached my version.
> > The first is that the thermal curve for Becattini is wrong.
> > >From PRC64 024901 one gets k+/k-=1.17 for pbar/p =0.4.
> > That gives k-/k+=0.85 at pbar/p=0.4 in good aggreement with our
> > data. This is the dashed line in my plot.
> >
> > Secondly I think it is crucial that we address the question of
> > weather we have local
> > strangeness neutrallity at different rapidities. If this were
> > so as long as the temperature does vary mu_s (and hence k-/k+)
> > is fixed for a given mu_b (ie pbar/p). Therefore we should
> > see a universal curve of k-/k+ versus pbar/p. In my plots I have
> > shown our 130GeV data and pp data from (Alper et al). They
> > are both in good agggreement with our 200GeV data.
> >
> > Third all k-/k+ data lie above (pbar/p)**1/3. Thus we have
> > a positive mu_s which approches 0 as pbar/p goes to 1.
> >
> > Finally I would prefer to use the published NA44 pbar/p ratios
> > rather than the QM99 pbar/p values from NA49. The spokesman of
> > NA49 told me that he thought the pbar yields should go down.
> > This would bring there pbar/p closer to ours. Both experiments
> > aggree on k-/k+.
> >
> > AMPT does not reproduce the data, both k-/k+ and pbar/p are
> > too high. In my plots the yellow band shows AMPT for the same
> > rapidity region as our data. Also the Pt slopes are not quite
> > the same were as for us our ratios have no Pt dependence.
> >
> > Masashi has found that feed-down from weak decays does not
> > effect the k-/k+ or pbar/p ratios very much. This strengens
> > our case for using them in a thermal analysis.
> >
> > For my plot I guess errors of 10% for the pp data. Tess is typing
> > in the spectra for me so that I can get the proper errors.
> > The k-/k+ ratio E866 is at y=0 and would be somewhat lower if
> > averaged over the same region as the pbars, ie 1.0<y<2.2.
> >
> >
> > In summary it seems that a thermal description of our data
> > with T~160-170MeV and local strangeness neutrallity gives
> > a good description of our data. K-/k+ vs pbar/p looks like
> > a universal curve.
> >
> > Michael Murray, Cyclotron TAMU, 979 845 1411 x 273, Fax 1899
>
>
> ----------------------------------------------------------------------------
> ----
>
>
>
>
>
Michael Murray, Cyclotron TAMU, 979 845 1411 x 273, Fax 1899
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