jump to navigation

Proofread my PASCOS 2007 proceedings September 5, 2007

Posted by dorigo in books, language, personal, physics.
trackback

After polling my twentyfive readers (a wink to A.Manzoni’s “I promessi sposi”, cap.I, par.31) on whether I should play the game of cyclostyling proceeding papers or not, I decided that politeness comes first – I had been asked to produce a writeup of my talk, and I did it.

So, as usual, before submitting the manuscript to my editor and to the ArXiV, I ask here for your benevolent help. If you have time to read my five pages summarizing the status of precision measurements of electroweak observables at the Tevatron, please download my paper (in postscript[1.2Mb], or in pdf format[0.4Mb]) and provide any feedback you see fit. If you provide helpful comments, I will acknowledge your input in the paper, as I did already three times in the recent past.

Comments

1. Jon Lester - September 5, 2007

Hi Tommaso,

Very nice presentation. I have only find a clerical on pag. 5. Check the sentence “could strain it the to the breaking point”.

Best,

Jon

2. Jon Lester - September 5, 2007

Should be “I have only found…”. Sorry.

3. Tony Smith - September 5, 2007

Tommaso, thanks for putting up the draft of your PASCOS 2007 talk.
I do have a comment, but I think that it is not the sort of comment that you should “… acknowledge … in the paper …”.

On page 3 in the right plot of figure 2 there seems to be a bump in the W to e nu data for M_T around 170 GeV, which is the CDF accepted Tquark mass and the mass of the middle state in my 3-state Tquark model.
It also seems to me that there is a smaller bump around 130 GeV, which is the Tquark mass for the low state in my 3-state Tquark model.
Note that the right plot of figure 2 does not go above 200 GeV,
but
in figure 1 (both for 1-tagged and 2-tagged) it seems to me that there is a small peak around 220 GeV, which is the Tquark mass for the high state in my 3-state Tquark model.

Tony Smith

4. Louise - September 6, 2007

By the way, thanks for the link August 30. I think you appreciate how much criticism yours truly can take.

5. riqie arneberg - September 6, 2007

It is with extreme dissappointment that I must report finding no grammatical errors. (Of course, there is a sexist tone to the entire presentation)

6. dorigo - September 6, 2007

Hi Tony,

I honestly do not see the bumps you mention – I think they are quite reasonable fluctuations up and down in the spectra, especially in the top mass plot where stats are poor.

In any case, the W sample is really devoid of contaminations from top decays, because of the selection cuts applied to clean up the sample – among them, a jet veto.

Cheers,
T.

7. dorigo - September 6, 2007

Hi Lester,

thank you, corrected.

Hi Louise,

you’re welcome, and of course I do know it is tough for you, but keep doing what you do, you have people silently appreciating your work out there.

Hi Riqie,
🙂 of course, there are several sentences I inserted in the text that aroused my sexual appetite. I can’t help doing that, I am sick, sick, sick.

Cheers all,
T.

8. Tony Smith - September 6, 2007

Tommaso, maybe the bumps I see might be reasonable fluctuations, especially in light of your statement that “… the W sample is really devoid of contaminations from top decays, because of the selection cuts applied to clean up the sample – among them, a jet veto …”.

Here is a question that comes to mind, that might not be so important with respect to this situation,
but which frames an issue that might potentially be important with respect to how LHC might handle access to its data in the near future:

What if I wanted to see whether such Tquark bumps might exist, and so wanted to look at the sample without the Tquark suppressing selection cuts ?

How much trouble would it be for CDF to do such an analysis ?

Would CDF provide access to the sample data without such cuts to an outside analyst ?

Tony Smith

9. dorigo - September 7, 2007

Hi Tony,

a search for a top quark of 140 GeV or elsewhere was done – when the top had not been found yet. However, I admit that, once it was found conclusively at 174 GeV, people stopped looking elsewhere. In any case, the background modeling has now reached a precision which leaves little margin for other resonances, but admittedly one never knows, at least until a limit is extracted directly. One could say that the xs limits obtained until 1993 still apply though. If your t quark at 140 and its other instantiations at higher masses are predicted to have lower cross sections, they might as well be still allowed, considering some of the backgrounds are tuned using the data (and if some unknown signal is buried therein, it may therefore get washed away).

Doing such a search is tough because no grad student would be willing to waste his time on setting a limit (few would truly believe the top at 140 or 190 is there) and then being unable to publish it – the theoretical motivation for the search is wanting, given the lack of any publication in support. Yes, this is the trouble with mainstream physics.

There is no way you can get your hands on CDF or D0 run II data other than associating to somebody willing to do the analysis. When I did a search for associated VY production in 2001-2003, there was a chinese physicist from Berkeley who participated, and eventually he was accepted as co-author of the paper I wrote, although he always claimed he had seen a signal (I set a limit on the process).

D0 data from Run I is, however, public, or so I am told. However, it is tough to make anything of it without a detailed understanding of the detector, the data acquisition, and suitable monte carlo simulations.

Cheers,
T.

10. Count Iblis - September 9, 2007

Abstract:

Third line:

“The large datasets”—> “Large datasets”

Sixth line:

“The precise knowledge…are providing” —> “The precise knowledge…is providing”

Figure 1: GeV/c^2 is perhaps politically correct but measuring mass in energy units is also perfectly defensible. Units are human constructs anyway, c only appears in equations because we have declared time and space to be incompatible a long time ago before we knew about special relativity.

Page two, third line:

“…and are divided in a inner…” —-> “…and are divided in an inner…”

Page five, line 8: “…could strain it the to the breaking point” —>

“…could strain it to the breaking point”

11. Tony Smith - September 10, 2007

Tommaso, for the past few days I have been reconsidering what
I have been doing in physics.

You are an honest person and when you said earlier in comments here:
that you “… honestly do not see the bumps …”
and
that you “… think they are quite reasonable fluctuations …”
and
“… when the top … was found conclusively at 174 GeV, people stopped looking elsewhere …”
and
“… t quark at 140 … might as well be still allowed, considering some of the backgrounds are tuned using the data (and if some unknown signal is buried therein, it may therefore get washed away) …”
and
“… There is no way you can get your hands on CDF or D0 run II data other than associating to somebody willing to do the analysis …”
and
“… the theoretical motivation for the search is wanting, given the lack of any publication in support …”.

From those quotes, it is clear to me that I will not in my lifetime see any analyses of collider data that might confirm my model in which there is a low-energy Tquark state around 140 GeV,
especially
since there will never be a “publication in support” of my model because of blacklisting,
even though it is a model in which the Higgs as a TTbar condensate leads naturally to the Tquark, through variants of NJL models (work of Yamawaki et al), being not a simple single-state system like lighter quarks, but with mass states including around 140 GeV and 174 GeV.
so
I will quit wasting my time blogging and web site updating about such physics stuff,
but
I will leave you with one last set of questions, about old CDF and D0 semileptonic histograms:

With respect to the CDF figure shown (colored by me with blue for the peak around 174 GeV) at
http://www.valdostamuseum.org/hamsmith/CDF94.gif
do you agree with CDF that the green peak around 140 GeV is “a statistical fluctuation” ?

With respect to the D0 figure shown (colored by me with blue for the peak around 174 GeV) at
http://www.valdostamuseum.org/hamsmith/D097Mar.gif
do you think that its green peak around 140 GeV is also a statistical fluctuation ?

If they are both statistical fluctuations,
then
what are the odds of such large fluctuations showing up at the same energy level in two totally independent sets of data ?

It was fun doing such physics while there was some hope of seeing relevant analyses of collider results, but that is over now.

Tony Smith

12. dorigo - September 11, 2007

Hi Count,

thank you for your corrections… But they arrived too late! Well, I am happy the things you spotted were not too serious. Thank you anyway!

Cheers,
T.

13. dorigo - September 11, 2007

Dear Tony,

I think it would be sad if your model were not tested, now that we have a large dataset of top quark decays in CDF and D0 data, and the matter could be settled conclusively and satisfactorily for all.

I am unable to help you, but there might be others willing to go that extra mile and actually perform a search. However, I think there is another way. D0 made their Run I data public, and there is thus nothing preventing you from trying to spot a signal at 140 GeV in their samples. I think Gordon Watts might be able to help you with that. I have heard it claimed several times that D0 Run I data is public, but then never saw where they are…

Also, in a not too distant future the Run II data might become available as well.

As for the two plots you mention, they show single bin fluctuations at 140 GeV. I read 8 events in the CDF one, in the face of a background plus signal totalling probably 2.5, and 5 in the D0 one, with about 2 from bgr+”standard” ttbar. You ask what is the probability of such a fluctuation, and that I can answer. It is of the order of 4-sigma. However, one would be entitled to claim a 4-sigma effect only if one observed the data after predicting the location of the excess beforehand. In other words, a 13-over-4.5 event excess is less significant if it is allowed to sit anywhere in a plot. But maybe you had predicted the top at 140 before the CDF plot of 1994 came out, so that is not a concern.

My own concern as an experimentalist is that such a spike is not physical, given the mass resolution of CDF and D0 on a top quark decay. The top has a resolution of about 25 GeV, so in any one 10 GeV bin there cannot be more than 20% or so of the total. That spike may be very unlikely as a fluctuation, but it is even more so as a signal.

To be clear, there can be no effect that makes a signal significantly narrower than what it is expected. One would have to hypothesize that all jets in those events fluctuated to neutral pions (measured better), and still the resolution would be far, far larger than the 5-10 GeV necessary to at least hope that a significant portion of the signal falls in a single bin.

We can discuss more later…

Cheers,
T.

14. Tony Smith - September 12, 2007

Tommaso, you say “… the mass resolution of CDF and D0 on a top quark decay …[is].. about 25 GeV …”
and
Claudio Campagnari and Melissa Franklin said in hep-ex/9608003 “The Discovery of the Top Quark”:
“… The energy of a jet … resolution … is typically only of the order … 1.0 / sqrt(ET) (ET in GeV) …
This poor resolution is due to
(i) the intrinsic large fluctuations in the response of calorimeters to hadronic showers,
(ii) differences in the calorimeter response between charged hadrons and electrons or photons,
(iii) energy loss in uninstrumented calorimeter regions …
(iv) energy loss due to the use of a finite cone-size in jet reconstruction, and
(v) overlaps between the jet and hadrons from the underlying event …”.

Their figure 32 shows, for D0, “… jet energy resolution as a function of jet transverse energy (ET) …”,
and
it shows resolution ranging from about 0.25 for ET around 30 GeV to about 0.1 for ET around 70 GeV or above, which is pretty much what you said.

However, it seems to me that the consistency of the two plots I mentioned in that they both show narrow 10-GeV peaks around 140 GeV might indicate that the CDF and D0 detectors might really in fact have had somewhat better resolution.

Is it possible that, in an effort to be very conservative and absolutely certain that the Tquark discovery claim be ironclad,
the resolution could in fact have been better than they stated ?

Since, as I said, I have abandoned hope of ever seeing any analysis of recent data relevant to my model, I am not advocating that anyone spend any effort studying whether or not the resolution might have been underestimated, but I am just asking if it might have been possible, so maybe this comment is really pointless.

Tony Smith

15. Siul Segrob - October 1, 2007

This is a post for Tony Smith.

Sorry that I am using your webpage but I am trying to contact
Tony to discuss some ideas. His old address does not look to
be working right now.

Tony, please, could you send me your e-mail address ?

I am Siul.


Sorry comments are closed for this entry

%d bloggers like this: