Dear Michael,
Many thanks for your extensive and useful comments to the paper.
I reply in random order below.
1) we don't have y=2 K-ratios from Brahms. The PID was just too lousy and
the pt range too narrow. (Or ...?).
We include the y=0 results.
I agree that if we don't put them in here, they will never appear.
2) We'll add the kratio=pratio**1/3 curve on the plot. I like your point
that this is the mu_s = 0 limit. Also we'll add sentences
explaining that exponent 1/4 leads to mu_s = 1/4 mu_q.
3) The mu_q axis on the plot is calculated for constant T=170 MeV. This is
listed on the plot.
4) Becattini, does not supply any more points. This is his fig. 4. it
assumes zero strange fugacity. We have written to him. He may - or may not
supply a better curve.I assume that he cannot make a brodaer range simply,
since he elewhere argues for a non zero fugacity at lower energies.
5) we'll try to cut text. Unfortunately we are inventing new sentences at a
rate superior to the rejection rate!
again, many thanks for your efforts
best regards
JJ and Claus
____________________________________________________________
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: Sunday, June 30, 2002 1:10 AM
Subject: Comments on Ratios2.04
Dear Claus and Jens Jorgen,
attached is a MS word file with my comments on
the ratios paper. My apologies for the format but it was all I had. I have
converted it to plain text below.
Since reading my mail on Saturday night I have 2 more comments. The
(pbar/p)**1/3 curve is the line for zero chemical potential. It is
significant
that this doesn't fit at the AGS but is close to the data at RHIC. Second
the fact that AMPT does not fit is probably due to asymetries in the
treatment
of strange baryons and antibaryons, for (k-/k+) and trouble with stopping
for pbar/p. We learn something when models fail.
My main comments are listed below.
thanks for all your work.
Michael
Dear Jens Jorgen and Claus,
greetings from Virginia! I picked up
version
2.04 of the ratios paper just before I left Texas and read it in Arkansas.
The
centrality dependence looks nicer now. I think that we are getting there but
I
have comments on the language, Figs 2 and 4,
sensitivity to weak decay, the discussion and references.
I feel that Fig 4 is would be much better with the ISR pp data and the y~2
130GeV AuAu result. These have the advangtage of emphasizing that there is a
UNIVERSAL curve linking k-/k+ and pbar/p.
The NA49 data is extensive but not yet final. The errors shown are far too
large given the scatter of the points. Claus said that they were just an
estimate, if so we should show the real statistical and point to point
systematic errors as bars. Common systematic errors should be shown as a
band
since all points could move together. At y=0.3 the pbar/p ratio seems to
disagree with NA44 by about 80%. The NA44 data are final and submitted for
publication. I think we should remember Peter Seyboth's comment that he
expects
the pbars yields to go down from the values shown at QM99.
Of course I should take my own medicine and get better errors for the ISR
data.
The 130 y=2 ratios are interesting they are lower than the 200GeV ratios at
y=2 but still lies on the curve. Even if the errors are not as small as one
would like I think we should try to publish this point. Otherwise it will
never
see the light of day.
The legend takes up too much space. I see no need to have the names of the
collaborations on the plot. They can be put in the caption. The 17GeV data
should be shown with one symbol; open for NA49 and closed for NA44. With a
little latex effort you can then put the symbols in the caption and refer to
the different experiments there.
There are two candidates for lines, (pbar/p)**1/4 and (pbar/p)**1/3. The
first
has the advantage that it goes through the data the second that it has a
natural interpretation in terms of mu_s=0. As pbar/p goes to one the k-/k+
data
approach this line, implying that mu_s goes to zero as mu_q goes to zero.
This
of course is the situation at LEP. At the
AGS where pbar/p about 10**-4 the E866 data are about a factor of three
above
the showing that there is a significant mu_s there. Thus if we put the
(pbar/p)
**1/3 line on the plot we can discuss how mu_s is falling with mu_q.
(It is sometimes said that the parameters of the thermal model are mu_q and
T.
This is not quite true. There are three parameters mu_s, mu_q and T which
are
linked by constraints on strangeness neutrality and charge conservation.
This
means that we end up with only 2 free parameters that we can vary to fit the
particle ratios.)
The mu_q scale should not extend to 255MeV since that is not the mu_q
observed
there.
Rather we should show it only for our data at some of our data points. That
would have the advantage of reiterating that we see mu_q increase from 25MeV
to
120MeV as y goes from 0 to 2.9. The axis says mu_b but sometimes that is
taken
to be 3*mu_q.
Becattini's prediction is not a straight line but has a slight upward
curvature. Perhaps he will give us the points or we should read a few more
off
the curve.
The text is too long and Figure 2 provides an easy place to save space.
Making
it a 2*2 plot would save 9 column lines by eliminating one set of X scales.
(You can count this yourself). Currently we are not using the extra width
afforded by 2 columns so there is no loss in going to 2*2 format. Secondly
the
caption is too long. We should just call the high rapidity point y~2.3 in
the
legend. The caption should then say
"Pt and centrality dependence of the particle ratios." Also there is no need
for the "X"
error bars in Figure 2.
All the figures have ugly fonts. I would prefer a font that matches PRL.
Figure
1 should have panel d in mass**2 with only one x scale for panels d and c.
The references are out of order and should either be put into BIBTEX or
ordered
correctly. We could save space by combining some of our references, eg 11
and
12 both refer to multiplicity analysis and eliminating the
word "Collaboration".
The correct order is 1,2,6,7,8,9,4,5,3,10,11,12,17,13,19,16,15,14, and 20. I
don't see 18 at all. We should italize "et al" through out and always put
the
year in the right place which
I believe is at the end. Ref 20 is incomplete.
For the text and language we need to cut what is unnecessary.
Abstract:
The emphasis should be on moving from mid-rapidity where everyone else works
into the unexplored forward region. Also we say nothing about Fig 4.
After the third sentence I would add "The ratio k-/k+ = (pbar/p)**1/4 , for
AuAu and pp collisions over a range of sqrt(S) and rapidity when both are
evaluated in small rapidity regions,. Interpreted within a thermal model
this
implies local conservation of strangeness and an increase of mu_q from 25MeV
to
120MeV as y increases from 0 to 3."
Page 1: Paragraph 1, delete "Brookhaven Nat. Lab.", replace with BNL.
Para 2, delete "RHIC maximium energy"
Para 3, sentence 1delete "We find that," and "at the CERN-SPS"
Merge paragraphs 2 and 3
Page 2, second paragraph, sentence 1, say
"The BRAHMS detector consists of 2 magnetic spectrometers
that rotate in . (IP) [1]."
Make a new sentence:
"They cover the rapidity range .. "
Delete "Details of . [1]."
Sentence 4 should start
"This assembly .."
Sentence 5 " the FFS CONSISTS ."
For the last sentence we don't need "p \approx" since it is implicit.
Para 3
Split up the first sentence: "The TMA is . region. We determine the
centrality
from the number of charged particles that hit the detector [4,11,12]
Para 4 sentence 1, "40, 60 and 90 degrees"
Sentence 3: "Therefore most systematic errors associated with acceptance and
detector efficiency cancel in the particle ratios.
Para 5
"Figure 1 shows the particle identification capability of the two
spectrometers."
For Figure 1 we need only one "1/beta" and it should be rotated to read
horizontally.
Page 3
Para 2 last sentence
"Therefore we integrate our particle yields over P_T and the centrality
range 0-
20% before making the ratios."
The last sentence is very unclear. Given STAR's results and out pbar/p ratio
one gets
Lambdabar/pbar = 0.5. We should use that as a base to calculate the
correction
and quote how much this correction changes when we change lambdabar/pbar by
50%.
Figure 3 caption: delete "Measured" to save a line
Page 4 colum 2 first paragraph, delete "that we have measured"
In sentence 3 we need to note that the SPS and AGS ratios are measured over
small rapidity regions.
Para 2 delete "experiment" or change it to "collaboration"
"Fig" should be capatalised and "Figure" should be used at the beginning of
a
sentence. There should be one terminology for ratios, "antiparticle to
particle
ratios" is most explicit with "particle ratios" for short.
Please submit all the data to EPAPS and add a sentence "these data are
available at
[\cite Epaps]. This is the best way to preserve the data for posterity.
(Remember that we are comparing to 27 year old ISR data)
Thanks for all your work,
Michael
Michael Murray, Cyclotron TAMU, 979 845 1411 x 273, Fax 1899
----------------------------------------------------------------------------
----
Dear Jens Jorgen and Claus,
greetings from Virginia! I picked up
version 2.04 of the ratios paper just before I left Texas and read it in
Arkansas. The centrality dependence looks nicer now. I think that we are
getting there but I have comments on the language, Figs 2 and 4,
sensitivity to weak decay, the discussion and references.
I feel that Fig 4 is would be much better with the ISR pp data and the y~2
130GeV AuAu result. These have the advangtage of emphasizing that there is a
UNIVERSAL curve linking k-/k+ and pbar/p.
The NA49 data is extensive but not yet final. The errors shown are far too
large given the scatter of the points. Claus said that they were just an
estimate, if so we should show the real statistical and point to point
systematic errors as bars. Common systematic errors should be shown as a
band since all points could move together. At y=0.3 the pbar/p ratio seems
to disagree with NA44 by about 80%. The NA44 data are final and submitted
for publication. I think we should remember Peter Seyboth's comment that he
expects the pbars yields to go down from the values shown at QM99.
Of course I should take my own medicine and get better errors for the ISR
data.
The 130 y=2 ratios are interesting they are lower than the 200GeV ratios at
y=2 but still lies on the curve. Even if the errors are not as small as one
would like I think we should try to publish this point. Otherwise it will
never see the light of day.
The legend takes up too much space. I see no need to have the names of the
collaborations on the plot. They can be put in the caption. The 17GeV data
should be shown with one symbol; open for NA49 and closed for NA44. With a
little latex effort you can then put the symbols in the caption and refer to
the different experiments there.
There are two candidates for lines, (pbar/p)**1/4 and (pbar/p)**1/3. The
first has the advantage that it goes through the data the second that it has
a natural interpretation in terms of mu_s=0. As pbar/p goes to one the k-/k+
data approach this line, implying that mu_s goes to zero as mu_q goes to
zero. This of course is the situation at LEP. At the
AGS where pbar/p about 10**-4 the E866 data are about a factor of three
above the showing that there is a significant mu_s there. Thus if we put the
(pbar/p)**1/3 line on the plot we can discuss how mu_s is falling with mu_q.
(It is sometimes said that the parameters of the thermal model are mu_q and
T. This is not quite true. There are three parameters mu_s, mu_q and T which
are linked by constraints on strangeness neutrality and charge conservation.
This means that we end up with only 2 free parameters that we can vary to
fit the particle ratios.)
The mu_q scale should not extend to 255MeV since that is not the mu_q
observed there.
Rather we should show it only for our data at some of our data points. That
would have the advantage of reiterating that we see mu_q increase from 25MeV
to 120MeV as y goes from 0 to 2.9. The axis says mu_b but sometimes that is
taken to be 3*mu_q.
Becattini's prediction is not a straight line but has a slight upward
curvature. Perhaps he will give us the points or we should read a few more
off the curve.
The text is too long and Figure 2 provides an easy place to save space.
Making it a 2*2 plot would save 9 column lines by eliminating one set of X
scales. (You can count this yourself). Currently we are not using the extra
width afforded by 2 columns so there is no loss in going to 2*2 format.
Secondly the caption is too long. We should just call the high rapidity
point y~2.3 in the legend. The caption should then say
"Pt and centrality dependence of the particle ratios." Also there is no need
for the "X"
error bars in Figure 2.
All the figures have ugly fonts. I would prefer a font that matches PRL.
Figure 1 should have panel d in mass**2 with only one x scale for panels d
and c.
The references are out of order and should either be put into BIBTEX or
ordered correctly. We could save space by combining some of our references,
eg 11 and 12 both refer to multiplicity analysis and eliminating the word
"Collaboration".
The correct order is 1,2,6,7,8,9,4,5,3,10,11,12,17,13,19,16,15,14, and 20. I
don't see 18 at all. We should italize "et al" through out and always put
the year in the right place which
I believe is at the end. Ref 20 is incomplete.
For the text and language we need to cut what is unnecessary.
Abstract:
The emphasis should be on moving from mid-rapidity where everyone else works
into the unexplored forward region. Also we say nothing about Fig 4.
After the third sentence I would add "The ratio k-/k+ = (pbar/p)**1/4 , for
AuAu and pp collisions over a range of sqrt(S) and rapidity when both are
evaluated in small rapidity regions,. Interpreted within a thermal model
this implies local conservation of strangeness and an increase of mu_q from
25MeV to 120MeV as y increases from 0 to 3."
Page 1: Paragraph 1, delete "Brookhaven Nat. Lab.", replace with BNL.
Para 2, delete "RHIC maximium energy"
Para 3, sentence 1delete "We find that," and "at the CERN-SPS"
Merge paragraphs 2 and 3
Page 2, second paragraph, sentence 1, say
"The BRAHMS detector consists of 2 magnetic spectrometers
that rotate in . (IP) [1]."
Make a new sentence:
"They cover the rapidity range .. "
Delete "Details of . [1]."
Sentence 4 should start
"This assembly .."
Sentence 5 " the FFS CONSISTS ."
For the last sentence we don't need "p \approx" since it is implicit.
Para 3
Split up the first sentence: "The TMA is . region. We determine the
centrality from the number of charged particles that hit the detector
[4,11,12]
Para 4 sentence 1, "40, 60 and 90 degrees"
Sentence 3: "Therefore most systematic errors associated with acceptance and
detector efficiency cancel in the particle ratios.
Para 5
"Figure 1 shows the particle identification capability of the two
spectrometers."
For Figure 1 we need only one "1/beta" and it should be rotated to read
horizontally.
Page 3
Para 2 last sentence
"Therefore we integrate our particle yields over P_T and the centrality
range 0-20% before making the ratios."
The last sentence is very unclear. Given STAR's results and out pbar/p ratio
one gets
Lambdabar/pbar = 0.5. We should use that as a base to calculate the
correction and quote how much this correction changes when we change
lambdabar/pbar by 50%.
Figure 3 caption: delete "Measured" to save a line
Page 4 colum 2 first paragraph, delete "that we have measured"
In sentence 3 we need to note that the SPS and AGS ratios are measured over
small rapidity regions.
Para 2 delete "experiment" or change it to "collaboration"
"Fig" should be capatalised and "Figure" should be used at the beginning of
a
sentence. There should be one terminology for ratios, "antiparticle to
particle ratios" is most explicit with "particle ratios" for short.
Please submit all the data to EPAPS and add a sentence "these data are
available at
[\cite Epaps]. This is the best way to preserve the data for posterity.
(Remember that we are comparing to 27 year old ISR data)
Thanks for all your work,
Michael
This archive was generated by hypermail 2b30 : Sun Jun 30 2002 - 06:31:05 EDT