Micha Dear Jens Jorgen,
thanks very much for sending out the two
drafts. Here are some remarks on
the ratios paper.
My first question is does the mechanism of stoppiing change from pp to AuAu?
At the ISR the R-807 collaboration measured pi+-, k+-,p and pbar from pp and
pbarp coolisions.
They find that 16% of the pbars observered at y=0 come from the fragmentation of
the beam.
Note each beam had an energy of 26GeV so sqrt(s)=52GeV. They found pbar/p=.6 for
pp collisions.
This seems very close to our situation.
I could not find anything about pbar/p from alpha alpha collisions at the ISR.
There may be
something in CERN-EP/84-112 by M.A. Faessler but I could not find the report on
the Web. Hans should be an
expert.
If you are going to report K+/K- and pbar/p why not try to connect them. It
would be simple to
do a chemical analysis at y=0. At QM01 people were even saying that you should
only use the
central rapidity ratios at sqrt{s}=130GeV. Another nice way of doing this would
be to plot
pbar/p versus k+/k- versus sqrt{s}. This should show a clear trend. One could
put pp results on
the same plot.
Do we still have strong pbar absorbtion at RHIC?
does pbar/n_part (or pbar/pi) increase with centrality? At the SPS it was flat.
I think it would be very useful to try to get a k+/k- ratio in the FRS.
One idea would be to devide the mass**2 spectra directly. Presumably the pion
contamination in the decreases with mass**2 and so the ratio should approch the
true
value for mass**2=.3 or so.
I think it would be very good to convert the tex to latex and to include the
plots as .eps files.
I have included some references that may be useful. I will find the model ones
too.
Yours Michael
\bibitem{ZDCNim} % The RHIC Zero Degree Calorimeter
C. Adler, et al., submitted to Nuclear Instruments and Methods,
xxx.lanl.gov/abs/nucl-ex/0008005
\bibitem{NA44PbPbK} % Strange Meson Enhancement in PbPb Collisions at 158 GeV/c
Bearden, I.G. et al.; Phys. Lett. B 471, 6-12 (1999)
xxx.lanl.gov/abs/nucl-ex/9907013
\bibitem{ NA44Spbar} %Proton and Antiproton Distributions at Midrapidity in
Proton-Nucleus and Sulphur-Nucleus Collisions
Bearden, I.G. et al.; Phys. Rev. C57 837-846 (1998)
\bibitem{NA44SAK} % Charged Kaon and Pion Production at Midrapidity in
Proton-Nucleus and Sulphur-Nucleus Collisions} \\
Boggild, H. et al.; Phys. Rev. C59 328-359 (1999)
xxx.lanl.gov/abs/nucl-ex/9808002
% K-/K+ at y_cm falls from pBe to SPb while pbar/p increases.
\bibitem{ NA49pbar} % Antiproton production in nuclear collisions at 158 A
GeV/c
G.I. Veres et al., Nucl. Phys. A 661 383c-386c.
\bibitem{NA49stop} %Stopping: from peripheral to Central Nuclear Collisions at
the SPS
G.E. Cooper et al., Nucl. Phys. A 661 362c-365c
% Beautiful proton distributions versus rapidity and centrality.
\bibitem{NA49kaon} % Strangeness production in nuclear collisions-recent
results from NA49.
C Hohne et al., Nucl. Phys. A 661 485c-488c
% Shows k+/pi and k-/pi vs sqrt{s} for AA and pp
\bibitem{NA49QM99} F. Sikler et al., % Hadron Production from NA49 at 158GeV/c/A
% K+ and K- increase with n_part whereas pbar does not
\bibitem{NA52QM99} %Impact parameter dependence of pi+-,K+- ,pbar,d & dbar for
PbPb
S. Kabana et al., Nucl. Phys. A 661 370c-373c
% At low Pt pbar/n_part FALLS as n_part increases while K+/n_part and K-/n_part
increase.
el Murray, Cyclotron TAMU, 979 845 1411 x 273, Fax 1899
This archive was generated by hypermail 2b29 : Wed Jan 24 2001 - 17:02:03 EST