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Here is a copy of my e-mail correspondence with one of the authorsof a paper entitledExperimental evidence for G.U.T. Proton Decay,hep-ex/0008074, that was dated 30 August 2000 and appeared on theLos Alamos e-print arXiv on 31 August2000, which paper says: :

"... in Kolar ... an experiment to detect proton decay hasbeen carried out since the end of 1980. Analysis of data yielded...

the life time of the proton is about 1 x 10^31 years...".

and which paper I describe on myweb page about SU(5) GUT physics.


Here is the e-mail message that I received,

which includes a quotation of my original message of inquiry:

Delivered-To: tsmith@innerx.netFrom: "Kawakami" <kawakami@sci.osaka-cu.ac.jp>To: "Tony Smith" <tsmith@innerx.net>Subject: RE: Kolar proton decay paperDate: Tue, 17 Oct 2000 17:56:07 +0900MIME-Version: 1.0X-Priority: 3 (Normal)X-MSMail-Priority: NormalX-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700Importance: NormalDear Dr. T.Smith,Thank you very much for your e-mail. I have not received any comments from other groups until now. There were some personal comments and Q and A are as follows:Q1. There must be strict selection criteria for the data.A1. Because of the great depth, number of event is so small as about 10/day.Therefore, we analyzed all events observed.Q2. Why do not compare with M.C. simulation.A2. We have used accelerator neutrino experiment by Frejuis group, which shows more background than M.C. simulation. Even if all neutrino events have isotropic distribution, background is less than 0.06 per events. Many of events have Kaons and background will be still smaller for such events.Q3. K.G.F. results seem to contradict to Super Kamiokande Report.A3. ?There are some differences in detecting K+ decay. However I think cause of the difference must be solved in Super Kamiokande experiment, because as mentioned in the K.G.F. paper, other experiment also finding K+ decay in similarrate of K.G.F.? In muon spectrum, new results by S.K. seems to be different from Kamiokande results. This is to be made clear by themselves. The main reason must be error estimation for S.K.the same reason may be applied for their e+, pi0 results. The point is that their error 2.5% in energy estimation is unbelievable for me. It should be more and a function of energy.Q4. How is the report by Sudan 2 compared with KGF results?A4. Their result for e+, K0: one event in 4.4 kty with the detection efficiency 16 % agrees well to the K.G.F. results 3 events in 1.7 kty with almost full efficiency.Q5. Is there any difference compared with these experiments?A5. KGF group learns from candidate events that Fermi momentum of protons in Fe nuclei is less than about 200 MeV/c which can be seen from back to back configuration of the events and also the width of neutrino, pi+ energy distribution.I hope to discuss with all above experimental groups to finalize the results, but no chance until now.With best wishes,Sincerely yours,S.MiyakeProfessor Emeritus of Osaka City UniversityC/O Professor Saburo KawakamiSaburo KawakamiFaculty of ScienceOsaka City UniversityTEL 81-6-6605-2645FAX 81-6-6605-2522kawakami@sci.osaka-cu.ac.jp-----Original Message-----From: Tony Smith [mailto:tsmith@innerx.net]Sent: Wednesday, October 11, 2000 8:31 AMTo: kawakami@sci.osaka-cu.ac.jpCc: tsmith@innerx.netSubject: Kolar proton decay paperI have been reading with interest your paperExperimental evidence for G.U.T. Proton DecayAuthors: H.Adarkar, S.R.Dugad, M.R.Krishnaswamy, M.G.K.Menon,B .V.Sreekantan, Y.Hayashi, N.Ito, S.Kawakami), S.Miyake, Y.Uchihoriwhich paper I found on the Los Alamos e-print archives athttp://xxx.lanl.gov/abs/hep-ex/0008074which paper says"...  in Kolar Gold Fields ... an experiment to detect proton decay... yielded the following results;(l) the life time of proton is about 1 x 10^31 years ...... This value ... is well within the range of predictionsbased upon minimal SU(5)  ...... there are a number of reports from other experiments... which have reached a general consensus among themselvesthat they have not found any conclusive evidence for proton decay ...... and that the life time must be as long as 10^33 years ...This conclusion is indeed in direct conflict with our results ...".Your paper then discusses results of other groups,such as Mont Blanc, Frejus, Kamiokande, and IMB,andyou say that, for example in the case of some events at IMB,"... if these features are ascribed to fluctuations in cascade showers,...their observed rate of candidate event becomes close to our results. ...".Since your results, if true, could support the SU(5) model,andsince the validity of the SU(5) model is important to me,I have been trying to find comments of other groups on your paper.However,I have not been able to find any such comments,andI would like to know:Have you received any comments from other groups on your paper ?If you have received any such comments, what are they ?Tony Smith     10 October 2000

 


 

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