Comments on An efficient method for mapping the 12C+ 12C molecular
resonances at low energies
Xiangqing Yu1,*
1Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
The goal of this reply is to draw attention of the readers that the major problems rose in the paper authored by X. Tang et al. [1], this is a brief analysis of the paper [1], there is some inconsistency in the paper [1], there are some errors in the paper [1], and there are some groundless exaggerated boasts in the paper [1].
The paper of 'An efficient method for mapping the 12C+ 12C molecular resonances at low energies' was published in NUCL SCI TECH [1], but there are some problems and shortcomings in the paper.
The author [1] wrote that nuclear structural research, but as far as I know, Nuclear structural research is usually written as nuclear structure research or nuclear structure study, Nuclear structural research may be a kind of innovation in nuclear structure research, is not it?
The author wrote that molecular resonance in the Keywords, but there are no exact study results that address the molecular concept resonance and there are no the right experimental methods to detect the molecular resonance in the whole paper. The 12C+ 12C molecular resonances represent true cluster states in the 24Mg compound system, or whether they simply reflect scattering states in the ion-ion potential [2], and the cluster physics in the Wikipedia is described as small, multiatom particles. As a rule of thumb, any particle of somewhere between 3 and 3×107 atoms is considered a cluster [3], the cluster is no less than 3 nucleons in the Wikipedia [3], while in the paper [1] the authors just measure the proton which contains 1 nucleon. If all the residual nuclei which contain no less than 3 nucleons in the nuclear reactions could be treated as molecular, then all the resonances of the residual nuclei which contain no less than 3 nucleons in nuclear physics can be treated as molecular resonances, isn't it ridiculous?
In the reference [4]E. Almqvistet et al. wrote that the results strongly suggest spins 2 and 4 for the 'quasimolecular' states at 19.5- and 19.9-MeV excitation in Mg24 , The partial widths of these states reduced to units of📷appropriate to each channel are given; in these units the C12 width is more than ten times the average width for α-particle emission and one hundred times the average nucleon width. In the reference [5]The nucleus 8Be has been conjectured to resemble a molecule of two interacting α-particles. A crucial test of this conjecture is the electromagnetic transition between the molecular resonances. This paper discusses the earlier indirect bremsstrahlung measurements and describes a recent experiment on the direct measurement of γ-transition between the 4+ and 2+ resonances, while the author [1] wrote that Each detector was covered with a 12.7-📷m-thick Al foil in the front to completely stop the α particles emitted from the 12C(12C,α)20Ne reaction, if the α particles was completely stopped, then all then ejectiles whose mass are heavier than α particle could also be completely stopped for the stop power of the ejectiles, there are only particles whose mass number are less than α particle mass number in the energy spectrum of Fig. 5 [1], in this experimental method [1] how to determine the C12 width as molecular resonances without gamma ray detection? The correct experimental method to detect the molecular-like resonance is detect the 12C molecular as a integral cluster
or the correct experimental method to detect the gamma or other signal of the excited states of the 12C, so the red mark of 'Resonance' of molecular resonances in the energy spectrum of Fig. 5 [1] could not be proved by compared with previous references or other methods, while red mark of 'No resonance' in the energy spectrum of Fig. 5 [1] is a real resonance, otherwise why the highest energy of proton is less than 2.5 MeV? If the true p1 events were distributed in the range from 7 to 8.2 MeV in the energy spectrum of Fig. 6 [1] is correct, then why is the highest energy of proton is about 5 MeV or more than 5 MeV in Fig. 3 [1], why is that? These are phenomena of logical contradiction, so there are no exact study results that address the molecular resonance in the whole paper, the author just use the the expression of molecular resonances to catch our eyes even he does not know what is the exact physical meaning or even he does not know what is the exact detecting method of the molecular resonances.
In the reference [6]T. Spillane et al. wrote that the data exhibit a pronounced resonance structure down to our low-energy limit, where a strong resonance is found at ER = 2138 ± 6 keV (width 📷< 12 keV) , if we could not trust T. Spillane's experimental result and others, then what will be trusted by us? and if we could trust T. Spillane's experimental result and others, then the results of the paper [1] are not correct because the experimental method of the paper [1] is to detect the proton while the experimental method of T. Spillane's paper is to detect gamma ray. There is no any resonance phenomenon at ER = 2138 ± 6 keV with so called thick target method in the result of the paper [1], but there is a strong resonance phenomenon is found at ER = 2138 ± 6 keV in T. Spillane's result, the author [1] wrote that the 12C(12C, p)23Na reactions were measured by experiments in the center of mass energy range of 3-5.3 MeV using thick targets. The author also wrote an infinitely thick target (i.e., thickness much greater than the beam range inside the target material) is used in this method, but the author wrote two contradictory descriptions, one description is the center of mass energy range of 3-5.3 MeV, and the other description is the center of mass energy range of 0-5.3 MeV for an infinitely thick target, It is now clear that the efficient thick target method outlined in the present work [1] will not be useful in searching for potentially existing molecular-like resonances of 12C+ 12C or resonances of 12C(12C, p)23Na in the energy range 1 MeV<Ecm<3 MeV, because there are not any proton resonance peaks or other useful signals beween the energy range 1 MeV<Ecm<3 MeV in the energy spectrum [1].
The author [1] wrote that to precisely map the resonant structures, fine energy steps (e.g., 📷<100 keV in the laboratory frame) are required. The yield difference between two adjacent energy points Y(E) and Y(E-📷) is calculated to determine the dY/dE. The author also wrote therefore, a range of reaction energies [Ebeam-📷E, Ebeam] is scanned with a single, constant beam energy. The effective width of the scan, 📷E, usually spans from 500 to 800 keV, but the author wrote two contradictory descriptions, although there is some difference between the 📷 energy in the center-of-mass frame and the 📷E in the laboratory frame, the 📷E =500 keV is the same as 📷=250 keV, is 250 keV smaller than 100 keV? isn't this ridiculous?
The author [1] wrote that the reaction Q-value spectrum is computed from Eq. 2 [1] with a constant incident energy of Ea =8.2 MeV, I think the Q-value can be calculated with the already known nuclear data, and that the reaction Q-value spectrum is computed from Eq. 2 [1] with a constant incident energy of Ea =8.2 MeV is a repetitive work of no great significance in the 12C(12C, p)23Na reaction, is it exaggerated boast or does the author shuffle up a paper with little self-confidence? The author [1] wrote that the Q-value spectrum, and the Q-value spectrum concept is not suit to be utilized here [1] because the Q-value of the reaction channel 12C(12C, p)23Na is a fixed value, a fixed value is not much wider spectrum or simple sharp Gaussian shape spectrum [1]. The author [1] wrote that the Q-value spectrum obtained with a thin target is expected to be narrowly 1.80 MeV, it is not narrowly or narrow 1.80 MeV, it is a fixed value of 1.80 MeV which can be calculated with the already known nuclear data.
The author [1] wrote that the p1 channel events obtained with the thick target form a wide Q-value spectrum when we compute the Q-value using a fixed beam energy, Ea =8.2 MeV, is it funny?
The author [1] wrote that the Q-value of the p0 channel also has a low-energy tail, similar to the p1 channel. These low-energy events from the p0 channel interfere with the high-energy events from the p1 channel. As shown in Fig. 5 [1]. As we know there are some necessary conditions of wave interfere phenomena, the wave length of matter-wave [7] is too short for heavy matter, if the wave length of matter-wave [7] was shorter than the matter size, then it is usually difficult to observe the wave-like characteristics, and the author [1] can not say that the matter-wave of earth interfere with the matter-wave of moon, the author [1] must prudently say that the matter-wave of superheavy nucleus interfere with the matter-wave of another superheavy nucleus, and the author [1] must prudently say that the matter-wave of proton interfere with the matter-wave of another proton if they could not have the same frequency or very similar frequency, obviously there is dominant superposition of p1 energy spectrum and p0 energy spectrum, which is not dominant interfere phenomena, the reason is that the wave length of 5 MeV proton is about 1.28📷10-14m, the wave length of 2.2 MeV proton is about 1.93📷10-14m, the wave length of 1.6 MeV proton is about 2.27📷10-14m, while as we know the size of proton is about 8.4-8.7📷10-14m, the length of matter-wave of proton is smaller than the size of proton in the paper [1], so it is usually difficult to observe the wave-like characteristics, then author [1] wrote that 'the Q-value of the p0 channel also has a low-energy tail, similar to the p1 channel. These low-energy events from the p0 channel interfere with the high-energy events from the p1 channel.' is wrong.
I do have my doubts about only the first author Xiao-Dong Tang and the corresponding author Xiao Fang know the process of posting a paper [1], but whether do other authors really know that send an article to a the magazine NUCL SCI TECH [1] or post a paper in the journal NUCL SCI TECH [1], it is really to be queried, and it can be proved by the expression of the correspondence author: akram@comp.tamu.ed, the correct expression is author for correspondence or the correct expression are other expressions.
In the reference [8] although the first authour is A. M. Mukhamedzhanov, as far as I know X. Tang who act as an organizer and pusher of posting a new comments paper, and as far as I know X. Tang had found D. Y. Pang for a help to write the comments [8], and then A. Tumino et al. come on Reply to the Comments on the 12C+12C fusion S*-factor, but it is strange that I can not search the author [1] Xiao-Dong Tang i.e. the author of the reference [8] the organizer X. Tang's Reply to Reply to the Comments on the 12C+12C fusion S*-factor, why?
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[1] Xiao-Dong Tang et al.,An efficient method for mapping the 12C+ 12C molecular resonances at low energies. NUCL SCI TECH 30, 126 (2019).
[4] E. Almqvistet et al., Spins and Partial Widths of Quasimolecular Resonances in C12+C12 Interactions. Phys. Rev. 130, 1140(1963).
[5] D R Chakrabarty, Electromagnetic transition between molecular resonances in 8Be. Pramana 83(5), 635-642(2014).
[6] T. Spillane et al., Study of the 12C+12C fusion reactions near the Gamow energy. Phys.Rev.Lett. 98, 122501(2007).
[7] Uwe Becker, Matter-wave interference made clear. Nature 474, 586-587(2011).
