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REVIEW 4 major objections 5 minor 16 references

GECAM Discovery of Peculiar Oscillating Particle Precipitation Events

T0 review · 4 major / 5 minor · reviewed 2026-08-15 · deepseek-v4-flash

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Pith's one-line read Two charged-particle precipitation events detected by GECAM-B on 21 March 2024 oscillated at about 5 and 6 hertz with no lightning association, a combination that challenges the standard electron-bounce explanation.

desk verdict Real and new GECAM observations of sub-second oscillating particle precipitation, but the periodicity significance is asserted rather than demonstrated; the paper deserves a referee. read the letter →

arxiv 2505.06192 v1 pith:EOLOCFYR submitted 2025-05-09 astro-ph.HE astro-ph.EPphysics.ao-phphysics.space-ph

Chenwei Wang , Shaolin Xiong , Yi Zhao , Wei Xu , Gaopeng Lu , Xuzhi Zhou , Xiaocheng Guo , Wenya Li
show 47 more authors
Xiaochao Yang Qinghe Zhang Xinqiao Li Zhenxia Zhang Zhenghua An Ce Cai Peiyi Feng Yue Huang Min Gao Ke Gong Dongya Guo Haoxuan Guo Bing Li Xiaobo Li Yaqing Liu Jiacong Liu Xiaojing Liu Xiang Ma Wenxi Peng Rui Qiao Yangzhao Ren Liming Song Wenjun Tan Jin Wang Jinzhou Wang Ping Wang Yue Wang Xiangyang Wen Shuo Xiao Shenlun Xie Yanbing Xu Wangchen Xue Sheng Yang Qibin Yi Zhenghang Yu Dali Zhang Fan Zhang Jinpeng Zhang Peng Zhang Wenlong Zhang Yanqiu Zhang Shuangnan Zhang Zhen Zhang Haisheng Zhao Xiaoyun Zhao Chao Zheng Shijie Zheng
This is my paper · ORCID
classification astro-ph.HEastro-ph.EPphysics.ao-phphysics.space-ph PACS 07.85.-m29.40.-n95.55.Ka95.85.Pw07.87.+v
keywords oscillatingparticleprecipitationGECAM-Bchargedsub-secondperiodicityspectrallaggeomagneticstormlightning-inducedelectronlowEarthorbitdetectors
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

Charged-particle precipitation in Earth's magnetosphere usually appears as a slow swell in flux, but on 21 March 2024 the GECAM-B satellite caught three events near Madagascar in which the flux rose in under a second; two of them pulsed about five and six times per second for several seconds. The paper argues that these pulses are real physical oscillations rather than detector artifacts, because the engineering and science data agree and the count rates stay far below saturation, and that the two periodic events are not linked to lightning. It also reports that in one event the arrival-time lag between low- and high-energy particles flips from low-energy-first to high-energy-first across successive pulses, while the pulse spectrum is harder at each pulse peak than at its trough. If the interpretation holds, these events represent a rare or new class of low-latitude oscillating particle precipitation whose origin remains unexplained.

What carries the argument

The load-bearing instrument is GECAM-B's dual-detector suite: 25 gamma-ray detectors (GRDs) and 8 charged-particle detectors (CPDs), together with a data-acquisition system that timestamps events to 0.1 microseconds and records both scientific and engineering counts so that transmission saturation can be checked. The GRD/CPD combination allows the team to show the signal is dominated by charged particles rather than photons, and the timestamping plus multi-channel readout is what makes a 5-6 Hz modulation with millisecond-scale pulse rises visible at all. On the analysis side, frequency analysis of 1-ms light curves, wavelet time-frequency analysis, hardness ratios, and energy-time maps of individual mini-pulses carry the argument that the periodicity is physical, frequency-stable, and accompanied by an evolving spectral lag.

What would settle it

Shuffle the arrival times of the detected particles within a single OPP burst while preserving the overall count-rate envelope and recompute the power spectrum; if the 5 or 6 Hz peak survives at comparable significance, the periodicity is an artifact of the burst shape rather than a true oscillation. A positive control would be a future overflight of the same region by GECAM-B or another low-Earth-orbit detector showing the same frequency and spectral-lag pattern.

Watch

Extended reading notes

Core claim

GECAM-B detected three charged-particle precipitation events, tn240321a, tn240321b, and tn240321c, on consecutive orbits during the geomagnetic storm of 21 March 2024, and the two bright ones show clear quasi-periodic modulation at fundamental frequencies of roughly 5 and 6 Hz, with harmonic and subharmonic peaks in the frequency analysis of the count-rate series. The oscillation appears in both the gamma-ray detectors and the charged-particle detectors, spans a wide energy range (from below 100 keV to above 500 keV for tn240321b), shows no significant frequency evolution over time, and is also visible in the hardness ratio, meaning the spectrum hardens at each pulse peak and softens at each dip. One event displays a spectral-lag transition across mini-pulses: early pulses are low-energy-first, later pulses are high-energy-first, while the overall modulation frequency stays constant. The paper concludes that these are genuine local charged-particle events with intrinsic oscillations, not instrumental artifacts, and finds no lightning within 1200 kilometers of the relevant magnetic footpoints, leaving the physical origin as an enigma and suggesting either a new type of particle precipitation or a peculiar lightning-induced electron precipitation.

Load-bearing premise

The load-bearing premise is that the three detections, made at nearly the same place on three consecutive 90-minute orbits, are three views of the same structure rather than three independent episodes; only under that assumption do they combine into one 3.5-hour-lived precipitation event, and the paper explicitly marks the association as conditional.

Editorial extensions

If this is right

  • The two periodic events would establish sub-second oscillating particle precipitation at low latitude, a regime previously considered rare and usually attributed to lightning-induced electron bounce motion.
  • The stable 5 and 6 Hz fundamentals with harmonics and subharmonics imply a periodic spatial or temporal structure with characteristic scale of roughly 1400 km and 1100 km along the orbit, and any candidate mechanism must reproduce that scale.
  • The spectral-lag flip in tn240321b would constrain energy-dependent precipitation timing: early pulses are low-energy-first, later pulses are high-energy-first, with no frequency drift, a pattern that bounce-motion models struggle to produce with equal pulse spacings.
  • If the three events are physically associated, the precipitation structure persisted at least 3.5 hours, which would require a long-lived magnetospheric or atmospheric source; the paper explicitly presents this lifetime as conditional on that association.
  • The non-association with lightning within 1200 km would differentiate these OPPs from canonical terrestrial electron beams and lightning-induced electron precipitation, making them either a new type of event or a peculiar variant of the latter.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • A testable extension: if the oscillation is spatial rather than temporal, the ~1400 km and ~1130 km pulse spacings should recur at the same geographic location on a later overflight, whereas a temporal source would drift with the spacecraft; reanalysis of GECAM-B orbits over the same region on other storm days could distinguish the two.
  • A testable extension: correlate the spectral-lag flip with energy-dependent drift-shell splitting at the measured L-shell; if the flip scales with energy as gradient-curvature drift predicts, a bounce- or drift-based mechanism would be revived despite the equal pulse spacings.
  • An untested scenario: the lightning-location network data mainly detect cloud-to-ground strokes, so an absence of strokes within 1200 km does not fully exclude a whistler launched by an undetected intra-cloud discharge; ground-based VLF receiver data at the conjugate footpoint could test this.
  • A statistical prediction: if these OPPs form a class tied to the Madagascar and South Atlantic region, a systematic catalog of GECAM-B particle events should show recurrence near this longitude during magnetic storms at similar 5-6 Hz frequencies.
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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

4 major / 5 minor

Summary. The paper reports three charged particle precipitation events detected by GECAM-B on 2024 March 21 during a geomagnetic storm, located south of Madagascar on three consecutive orbits. Two events (tn240321b and tn240321c) show apparent quasi-periodic modulation at fundamental frequencies near 5 Hz and 6 Hz, respectively, visible in both GRD and CPD count rates and in multiple energy bands. The authors argue from engineering-data consistency and sub-saturation count rates that the signals are not instrumental, and from CPD detections and the absence of corresponding astrophysical transients that they are dominated by charged particles. They further report energy-dependent oscillation amplitude, a hardness-ratio modulation, and a transition in the spectral lag of individual mini-pulses from 'softer-earlier' to 'softer-later', and they find no association with lightning in WWLLN data. The paper discusses several possible origins and concludes that the events may represent a new type of particle precipitation or a peculiar lightning-induced electron precipitation event.

Significance. If the periodicity and charged-particle origin are firmly established, this would be a notable discovery: sub-second oscillating particle precipitation at low latitude with stable frequencies and an energy-dependent spectral-lag evolution that challenges simple electron-bounce interpretations. The paper makes good use of GECAM's high time resolution and provides a careful instrumental cross-check, including simultaneous GRD and CPD signals, engineering-data consistency checks, and sub-saturation peak rates. The authors are appropriately cautious in presenting the physical-origin scenarios as speculative. However, the core claim of significant periodicity is currently supported only by visual inspection of PSDs, and the absence of a quantitative false-alarm analysis leaves the central assertion insufficiently supported. The reported 3.5-hour lifetime and the 'twin OPP' framing rest on an explicitly conditional association that is not independently verified.

major comments (4)
  1. [Section 3.1, Fig. 3a,b] The central claim of 'significant periodicity' is not quantified. The paper states 'A series of harmonic and subharmonic frequencies can be clearly observed' but gives no significance threshold, false-alarm probability, or confidence interval for the PSD peaks. The null hypothesis is not trivial: the light curves have a strong FRED-like envelope (red noise at low frequencies), the 1 ms binning and any dead-time effects modify the white-noise level, and the search over frequency, harmonics, two energy channels, and two events adds a trials factor. Without a proper false-alarm estimate, e.g., by fitting the red-noise continuum and simulating surrogate light curves or by using a bootstrap, the classification of these events as genuinely periodic OPP is not established. Please report p-values or significance levels for the fundamental and harmonic peaks and the associated frequency uncertainties.
  2. [Section 3.1, spatial intervals] The inference of spatial intervals of ~1409 km (tn240321b) and ~1134 km (tn240321c) is presented as a direct consequence of the oscillation frequency and the satellite velocity, but this assumes that the oscillation is spatial structure rather than temporal modulation. The paper itself notes the long-standing temporal-versus-spatial debate; the wavelet result of a constant frequency over time is equally consistent with a temporal oscillator. The spatial-interval interpretation should be explicitly labeled as model-dependent, or additional evidence (e.g., inter-detector arrival patterns or phase coherence across the two events) should be provided. In addition, the quoted frequencies of ~5 Hz and ~6 Hz need uncertainty estimates and a statement of the frequency resolution of the PSD.
  3. [Section 3.1 and Table 1; Abstract] The abstract states a 'life time of more than 3.5 hours' as an outcome, but the only support is the explicitly conditional sentence in Section 3.1: 'if these three events are considered to be physically associated, then we can obtain a constraint on the duration of the particle precipitation, which lasted for at least 3.5 hours.' The physical association of tn240321a/b/c is not independently established. Moreover, the three events in Table 1 show longitudes of 46.66°, 41.09°, and 39.10°, which is a systematic westward drift, while the text describes the positions as exhibiting 'a trend of west to east'; this inconsistency needs clarification. Please either provide quantitative evidence for the association (e.g., magnetic conjugacy, drift-path compatibility, or similarity of spectral/temporal properties) or move the 3.5-hour lifetime into the discussion as a clearly labeled hypothesis.
  4. [Section 3.1 and Fig. 3e,f] The reported spectral-lag transition from 'softer-earlier' to 'softer-later' is a headline new feature, but it is described only qualitatively from energy-time images and scaled light curves. No quantitative lag measurements (e.g., cross-correlation lags or pulse-fit arrival times with uncertainties) are given for individual mini-pulses, making it impossible to assess the significance of the transition or its evolution over the event. Please provide numerical lags and errors, or explicitly reframe the claim as a qualitative visual impression rather than a measured result.
minor comments (5)
  1. [Fig. 3 caption] The caption contains multiple naming errors: it refers to 'tn240321c and tn240321d' (should be 'tn240321b and tn240321c'), and later to 'the fundamental frequency of tn240321a' and 'tn240321b' where the events discussed are tn240321b and tn240321c. Section 3.1 also cites 'Fig.3 e and d' where 'e and f' is intended. These inconsistencies make the figure difficult to interpret.
  2. [Section 3.2.4] The text says 'there are no signs of lightning activity within 1200 km from the GECAM-B nadir and southern magnetic footpoint of tn40321a and tn40321b'; the event names 'tn40321' should be 'tn240321', and the intended events are presumably tn240321b and tn240321c. Please correct the typography and ensure consistent event naming throughout.
  3. [Fig. 3] The abbreviation for the power spectrum is inconsistent: the text uses 'PSD' while the figure caption uses 'PDS'. Please standardize.
  4. [Section 2] The phrase 'The continuity of time and consistency of location suggests their association' is imprecise because the events are separated by approximately 100 minutes (nearly one orbital period). 'Continuity of time' should be replaced by a more accurate description, such as 'occurrence on consecutive orbits over a ~3.5-hour interval'.
  5. [Section 3.2.4] The lightning null result is reported without stating the WWLLN detection efficiency, the exact time window searched around each event, or the threshold for 'no signs of lightning activity'. Quantitative bounds on the expected number of lightning strikes within the search region and time window would make the null result interpretable.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: the paper reports observational measurements and direct unit conversions, with no fitted parameter renamed as a prediction and no load-bearing self-citation chain.

full rationale

This is an observational report rather than a derivation from a model. The central claim, that GECAM-B detected genuine periodic charged-particle precipitation, rests on measured count-rate light curves, a Leahy-normalized PSD computed with Stingray, and wavelet analysis, from which the fundamental frequencies of roughly 5 Hz and 6 Hz are read off directly. The spatial intervals of about 1409 km and 1134 km are obtained by multiplying the measured frequency by the satellite velocity, which is a direct unit conversion, not a prediction from a fitted model. The instrumental-origin checks compare engineering data with scientific data and peak count rates with saturation conditions; these are external consistency checks rather than circular arguments. The 3.5-hour lifetime inference is explicitly conditional in the text, and the association of the three events is framed as an assumption, not as a consequence of the periodicity analysis. While the paper cites several prior GECAM papers by overlapping authors, those citations support instrument design, calibration, and a previously reported TEB-like event; none of them is invoked as a uniqueness theorem or as the sole justification for the periodic signal. The comparison with the multi-peak TEB-like event is a data comparison, not an argument that reduces to the authors' prior conclusion. The absence of a quoted false-alarm probability or significance level for the PSD peaks is a legitimate statistical-support concern, but it is not circularity: the frequencies are measured from the data, and the claim of significance is under-quantified rather than defined into existence. No self-definitional, fitted-input-called-prediction, self-citation-load-bearing, imported-uniqueness, or ansatz-smuggling pattern is present. The paper's derivation chain is self-contained with respect to its observational inputs, so the circularity score is 0.

Assumptions & free parameters 0 free parameters · 6 assumptions · 0 invented entities

Six domain assumptions are listed; the most fragile is the physical association of the three events. No free parameters are fitted: the 5-6 Hz frequencies are measured PSD peaks and the spatial intervals are derived from orbital velocity. No new physical entities are invented; the 'new type of particle precipitation' is a classification suggestion, not a postulated mechanism.

assumptions (6)
  • domain assumption The GECAM-B GRD and CPD count rates during these events are dominated by charged particles rather than photons.
    Argued from simultaneous strong CPD (charged-particle-only) signals and the absence of astrophysical or solar transients in other monitors; cited in Section 2.
  • domain assumption The consistency between engineering and scientific data rules out transmission saturation as the source of the periodic signal.
    Section 2 states engineering and scientific data show good consistency and peak count rate below 20 kcps; this is an instrument-behavior assumption.
  • domain assumption The observed periodic modulation is a physical flux variation or static spatial structure rather than a detector readout cycle.
    Sections 2 and 3 argue against saturation but do not model possible periodic detector effects; the spatial interval interpretation assumes a static structure along the orbit.
  • domain assumption WWLLN detection is sufficient to conclude no lightning association within 1200 km.
    Section 3.2.4 uses the absence of WWLLN lightning as evidence against TEB and LEP; WWLLN has limited detection efficiency, so absence is weak evidence.
  • domain assumption The three events are physically associated with the same precipitation structure.
    Section 3.1: 'if these three events are considered to be physically associated, then we can obtain a constraint on the duration... at least 3.5 hours.' This underpins the twin-OPP and lifetime claims.
  • domain assumption Magnetic footpoint tracing and L-shell mapping are accurate enough for the spatial comparisons.
    Used in Sections 2 and 3 for footpoint locations and comparison with VLF transmitters; model accuracy is not quantified.

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Cite this review

Pith. "Pith review of GECAM Discovery of Peculiar Oscillating Particle Precipitation Events." pith.science (2026). https://pith.science/paper/EOLOCFYR

@misc{pith2026250506192,
  author       = {Pith},
  title        = {Pith review of: GECAM Discovery of Peculiar Oscillating Particle Precipitation Events},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/EOLOCFYR}},
  note         = {Machine review of arXiv:2505.06192}
}
read the original abstract

Charged particle precipitation typically manifests as a gradual increase and decrease of flux observed by space detectors. Cases with rapidly flux variation are very rare. Periodic events are even more extraordinary. These oscillating particle precipitation (OPP) events are usually attributed to the bounce motion of electrons, which are induced by lightning. Owing to the observation limitations, there has been debate regarding whether these oscillations originate from temporal flux evolution or spatial structure evolution. Here we report three peculiar charged particle precipitation events detected by GECAM during a geomagnetic storm on March 21, 2024, with two exhibiting significant periodicity. These events were observed around the same region during three consecutive orbits. Through comprehensive temporal and spectral analyses, we revealed that one of the OPP events exhibited a transition in spectral lag of mini-pulses, shifting from "softer-earlier" to "softer-later" while showing no significant time evolution in overall frequency characteristics. And there is no association found between these two OPP events and lightning activity. Several possible scenarios are discussed to explain these charged particles with a life time of more than 3.5 hours, but the nature of these three events remains an enigma. We suggest that these GECAM-detected OPP events may represent a new type of particle precipitation event or a peculiar Lightning-induced Electron Precipitations (LEPs).

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

16 extracted references · 14 canonical work pages

  1. [1]

    GECAM Discovery of Peculiar Oscillating Particle Precipitation Events

    Chenwei Wang, et al. Sci. China-Phys. Mech. Astron. * (*) V ol. * No. * 000000-1SCIENCE CHINA Physics, Mechanics & Astronomy * * V ol. * No. *: 000000 https://doi.org/?? © Science China Press and Springer-Verlag GmbH Germany , part of Springer Nature 2020 phys.scichina.com link.springer.com . Article . SPECIAL TOPIC: GECAM Discovery of Peculiar Oscillatin...

    work page Pith review arXiv 2020

  2. [2]

    softer- earlier

    generally larger than tn240321b and tn240321c. However, TEB samples are very rare, and their durations are generally very short (on the order of tens of milliseconds), typically allowing for the detection of only a bounced pulse. Only one case of a suspected multiperiodic TEB event has been reported until now, but its origin is still under debate. As for ...

    work page 2021

  3. [3]

    Journal of Geophysical Research (1896-1977), 69(21):4457–4479,

    high time resolution studies. Journal of Geophysical Research (1896-1977), 69(21):4457–4479,

    work page 1977

  4. [7]

    softer-earlier

    a, the orbit of GECAM-B from 2024-03-21T19:00:00 to 2024-03-22T00:00:00 are depicted as white lines, and the white right triangle indicate the direction of movement of GECAM-B, with the time interval of 600 s. The black triangle mark- ers represent lightning from 2024-03-21T19:40:26 (trigger time of tn240321a) to 2024-03-21T21:21:20 (trigger time of tn240...

    work page 2024

  5. [10]

    22 Y . Q. Liu, K. Gong, X. Q. Li, X. Y . Wen, Z. H. An, C. Cai, Z. Chang, G. Chen, C. Chen, Y . Y . Du, et al. The sipm array data acquisi- tion algorithm applied to the gecam satellite payload. arXiv preprint arXiv:2112.04786,

    work page Pith review arXiv

  6. [13]

    GECAM-B was launched in December 2020 and is operating in low earth orbit (LEO) with an altitude of∼600 km and 29◦ inclination angle [15]

    and GECAM-D [14]. GECAM-B was launched in December 2020 and is operating in low earth orbit (LEO) with an altitude of∼600 km and 29◦ inclination angle [15]. Two kinds of scientific payloads are equipped on GECAM-B, the gamma-ray detectors (GRDs)

    work page 2020

  7. [14]

    Journal of Geophysical Research (1896-1977), 71(3):803–823,

    diurnal and type e ffects. Journal of Geophysical Research (1896-1977), 71(3):803–823,

    work page 1977

  8. [15]

    Journal of Geophysical Research (1896-1977), 73(7):2355–2362,

    an asso- ciation between microbursts and vlf chorus. Journal of Geophysical Research (1896-1977), 73(7):2355–2362,

    work page 1977

Show all 16 references
  1. [16]

    and charged-particle detectors (CPDs) [17]. GRDs are highly sensitive to both photons and charged particles, while CPDs are designed to be only sensitive to charged particles and much less sensitive to photons, which makes GECAM able to distinguish whether a group of events is...

    2024

  2. [32]

    softer-earlier

    by three interesting events at about 2024-03-21T19:40:26 (UTC), 2024-03-21T21:21:20 (UTC) and 2024-03-21T23:03:13 (UTC) when the satellite passed the south of Madagascar, which can be seen in Fig.2, and these three events are denoted as tn240321a, tn240321b and tn240321c respe...

    2024

  3. [2020]

    SVOM gamma ray monitor

    55 Yongwei Dong, Bobing Wu, Yanguo Li, Yongjie Zhang, and Shuang- nan Zhang. SVOM gamma ray monitor. Science China Physics, Mechanics, and Astronomy, 53(1):40–42, January 2010

    2010

  4. [2021]

    23 Z. H. An, S. Antier, X. Z. Bi, Q. C. Bu, C Cai, X. L. Cao, Anna-Elisa Camisasca, Z. Chang, G. Chen, L. Chen, T. X. Chen, W. Chen, Yi- Bao Chen, Yong Chen, Yu-Peng Chen, Michael W. Coughlin, Wei-Wei Cui, Zi-Gao Dai, T. Hussenot-Desenonges, Yan-Qi Du, Yuan-Yuan Du, Yun-Fei Du...

  5. [2022]

    8 Z. Y . Liu, Q. G. Zong, R. Rankin, H. Zhang, Y . X. Hao, J. S. He, S. Y . Fu, H. H. Wu, C. Yue, C. J. Pollock, and G. Le. Particle-sounding of the spatial structure of kinetic Alfv´en waves. Nature Communications, 14:2088, April

  6. [2023]

    20 Y Zhao, Wangchen Xue, Shaolin Xiong, Qi Luo, Yuanhao Wang, Ji- acong Liu, Heng Yu, Xiaoyun Zhao, Yue Huang, Jinyuan Liao, Jian- chao Sun, Xiaobo Li, Qibin Yi, Ce Cai, Shuo Xiao, Shenglun Xie, Chao Zheng, Yanqiu Zhang, Chenwei Wang, Wenjun Tan, Zhiwei Guo, Chaoyang Li, Zheng...

    arXiv

  7. [2024]

    b, the count rate curve of GECAM-B of continuous 3 orbits with time resolution of 10 s, the hatched time intervals corresponds to SAA, where GECAM-B is not operating

    a, the SYM/ASY index for Earth magnetic field, which is accessed from World Data Center for Geomagnetism, Kyoto. b, the count rate curve of GECAM-B of continuous 3 orbits with time resolution of 10 s, the hatched time intervals corresponds to SAA, where GECAM-B is not operatin...

    2024

  8. [2025]

    26 S. X. Yi, C. W. Wang, X. Y . Shao, R. Moradi, H. Gao, B. Zhang, S. L. Xiong, S. N. Zhang, W. J. Tan, J. C. Liu, W. C. Xue, Y . Q. Zhang, C. Zheng, Y . Wang, P. Zhang, Z. H. An, C. Cai, P. Y . Feng, K. Gong, D. Y . Guo, Y . Huang, B. Li, X. B. Li, X. Q. Li, X. J. Liu, Y . Q....

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