Hi Tjeerd,
Below are some comments on LHCb-PAPER-2014-014 (Z-)
Greetings,
Gerco
47-48: "confidence level (CL) of the fit” -> does this mean p-value? Or perhaps: how is the C.L. of a fit defined?
48: “approximately flat” How is it possible that the p-value distribution from simulated data is not consistent with flat? This suggests some systematic effect which is then apparently NOT simulated? Explain!
62: “the CL is below …”: the CL of the fit? Then p-value. 64, 77, 78, 120, 153, : “the fit CL”: same as above
92-94: "We find that the simulated ∆L distribution follows a χ2 PDF with ndf = 7.50 ± 0.11 (statistical error)” : what distribution is EXPECTED? IS the chi2 distribution chosen more or less phenomenologically? What is the meaning of ndf in this case? Is it just some parameter used to parametrise the ∆L distribution, or is it related to something? In the next sentence the suggestion is made that it is somehow related to the number of free parameters in the Z- fit. Also, in what sense does taking ndf=8 result in a CONSERVATIVE result? Lastly, the distribution in fig. 3 doesn’t look like a chi2 distribution AT ALL!
107: “float all K∗ masses and widths while constraining …” : constraining HOW? By assigning a prior distribution (which??? Gaussian) to them according to the PDF values?
On 28 Mar 2014, at 09:03, Tjeerd Ketel tjeerd@nikhef.nl wrote:
Dear colleagues,
Bfys Meeting Friday 28 March at 9:30 in H331 and Vidyo
9:30 - 9:55 Staff meeting (only permanent staff)
10:00 - 10:50 Introduction and discussion of LHCb-PAPER-2014-012 "Measurement of the resonant and CP components in barB0 to J/psi pi+ pi- decay" by Vasilis Syropoulos Deadline: 01-Apr-2014 Link: http://cds.cern.ch/record/1669578
10:50 - 11:40 Discussion of LHCb-PAPER-2014-014 "The resonant character of the Z(4430)− state" Deadline: 01-Apr-2014 Link: https://cds.cern.ch/record/1670988
The material can be found at http://agenda.nikhef.nl/conferenceDisplay.py?confId=2843 and will be protected by lhcb, etc.
Vidyo link in Nikhef Bfys Meeting (at Institutes->Nikhef of Friday 14 March 2014) https://indico.cern.ch/event/307385/ protected by PIN 1328.
Best regards, Tjeerd_______________________________________________ Bfys-physics mailing list Bfys-physics@nikhef.nl https://mailman.nikhef.nl/mailman/listinfo/bfys-physics
- Gerco
Dr. C.J.G. Onderwater Faculty of Mathematics and Natural Sciences Fundamental Interactions and Symmetries Group Nijenborgh 4 NL 9747 AG Groningen Nederland Tel. +31(0)50-3633557 Tel. +31(0)50-3638774 Fax. +31(0)50-3634003