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Employees Dubna joint Institute for nuclear research, Moscow state technical University of radio engineering, electronics and automation Institute of applied physics of the Academy of Sciences of Moldova experimentally found traces of decay easy boson, not included in the Standard model.
The particle with the mass of which is estimated at approximately 38 MeV, while denoted simply as E(38). Her observation was reported by scientists at the recently concluded in Dubna Baldin international seminar on high energy physics problems, even before the speech published a Preprint of an article about his discovery.
It is worth saying that the Higgs E(38) mentioned in the literature in the past year: researchers from Portugal EEF van Beveren (Eef van Beveren) and George Rupp (George Rupp) found "the first signs" of his existence by looking at the data collected by the BABAR collaboration in collisions of electrons and positrons in the Collider PEP-II in the American National accelerator laboratory SLAC. In February 2012 physics has updated an article in which now was discussed not only information BABAR, but the results of the experiments conducted by the CDF collaboration (it will be recalled, was working on a proton-antiproton Collider "Tevatron" in National accelerator laboratory them. Fermi), CMD (electron-positron Collider VEPP-2M, Institute of nuclear physics. G. I. of nuclear physics, SB RAS), CB-ELSA (electron accelerator ELSA, University of Bonn) and COMPASS (Superproton synchrotron, the European organization for nuclear research). Representatives of the COMPASS, interestingly, has decided to actively protect the canonical interpretation of their data and published a short comment to the work of van Beveren and Group. Its essence is reduced to that found "peak" at approximately 38 MeV is an artifact specific spectrometer and specific measurement schemes and repeatable standard simulation Monte Carlo.
Many experts agreed with COMPASS and reviewed study van Beveren and the Group as a meaningless looking for signals in complex distributions (and not originally defined) form, with no serious physical basis. Now the attitude may change: the Russians were analyzed already not some combination of published data, and the results of experiments performed by them personally well known to them installed.
Scheme of Dubna of the experiment. S1 and S2 - scintillation counters. (Illustration of the authors.)
For conducting experiments in Dubna was used accelerator complex of the Nuclotron beam which fell on carbon or copper target. The deuteron (contains one proton and one neutron in the nucleus of deuterium, stable heavy isotope of hydrogen) on "the Nuclotron were dispersed to two or three GeV in terms of one nucleon, and the proton - to 4.6 GeV. Pilot scheme shown in the figure above, had two identical arms, practically located symmetrically with respect to the beam axis, and the results of collisions of particles with the targets were fixed deleted three meters Cherenkov gamma spectrometers.
These gamma-spectrometers and recorded evidence decays E(38) on pairs of photons (such decays, by the way, clearly indicate that E(38) refers to the bosons). Physicists have built a distribution of the number of photon pairs, registered in the right shoulder of the scheme, in their invariant mass (the amount for calculation of which need to know the energy of two photons and the angle between the directions of their movement), compared the obtained graph with background predictions of the Standard model and found projected van Beveren and RUPE peak in the area, 38 MeV. The signal was manifested in three different variants of the experiment: during insertion of protons and 2-gigaelectronvolts deuterons on a carbon target, and when getting more energy deuterons on the copper target.
Such information, it seems, was to convince the skeptics, but this shows how critical feedback Tommaso Dorigo (Tommaso Dorigo) on the work of Russian physicists did not happen. To understand Mr. Dorigo, the employee of the CMS collaboration, which performs experiments at the Large hadron Collider and recently reported about the discovery of the Higgs boson, you can: article dubnentsev written in a very, shall we say, unusual style. Traditionally in such research provides a brief description of the facility and some of its key characteristics like energy resolution, selection criteria of events, information about how to model the background, and the results of statistical analysis with familiar to readers of "CL" assessing the value of the signal - but nothing of this in the new Preprint no. He, in fact, is a set of homogeneous graphs, built for the aforementioned three variants of the experiment and different criteria (limits on the energy of the photons, the total energy of two photons and their scattering angle), which are produced without any comments.
Of course, the answers to many questions can be found in the previously published report about the experiments on the Nuclotron and the same Cherenkov gamma spectrometers (or in this post theorist Chris Austin (Chris Austin), which explains the increasingly available), but the design of critical articles about the observation of particles that do not fit into the Standard model, really surprised. To record the results of the authors also treated carelessly; approximating peaks of the Gaussian function, they are everywhere point of Central importance with incredible accuracy in five (!) decimal places, and in one case (38,4935 ± 1,02639) and does make a mistake, which is not always forgive students at the technical University - are of value and its uncertainty with a different number of digits after the decimal point.
Anyway, the situation should be clarified soon. According to Mr. van Beveren, a group of Dubna promised in the near future to make a detailed description of the measuring circuit and methods of analysis.
Based on the arXiv and blog entries Tommaso Dorigo and Chris Austin.