| 1. |
- Becares, V., et al.
(författare)
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Evaluation of the criticality constant from Pulsed Neutron Source measurements in the Yalina-Booster subcritical assembly
- 2013
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Ingår i: Annals of Nuclear Energy. - : Elsevier BV. - 0306-4549 .- 1873-2100. ; 53, s. 40-49
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Tidskriftsartikel (refereegranskat)abstract
- The prompt decay constant method and the area-ratio (Sjostrand) method constitute the reference techniques for measuring the reactivity of a subcritical system using Pulsed Neutron Source experiments (PNS). However, different experiments have shown that in many cases it is necessary to apply corrections to the experimental results in order to take into account spectral and spatial effects. In these cases, the approach usually followed is to develop different specific correction procedures for each method. In this work we discuss the validity of prompt decay constant method and the area-ratio method in the Yalina-Booster subcritical assembly and propose a general correction procedure based on Monte Carlo simulations.
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| 2. |
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| 3. |
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| 4. |
- Becares, V., et al.
(författare)
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Validation of ADS reactivity monitoring techniques in the Yalina-Booster subcritical assembly
- 2013
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Ingår i: Annals of Nuclear Energy. - : Elsevier BV. - 0306-4549 .- 1873-2100. ; 53, s. 331-341
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Tidskriftsartikel (refereegranskat)abstract
- The development of a reactivity monitoring system for subcritical reactors is a major task prior to industrial scale accelerator driven system (ADS) construction. Within the 6th European Framework Program, the IP-EUROTRANS project has performed a series of experiments at the Yalina-Booster subcritical assembly located at the Joint Institute for Power and Nuclear Research (JIPNR) of the National Academy of Sciences of Belarus, using a continuous (D, T) (fusion) neutron source in pulsed and continuous mode with short interruptions (beam trips). In this paper, the implementation and results of three different monitoring techniques intended to operate with continuous neutron sources will be presented, namely the source-jerk technique, the prompt decay constant technique and the current-to-flux technique. The results will be compared with the values of the reactivity obtained using the pulsed source in PNS experiments, discussed in detail in another paper.
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| 5. |
- Berglöf, Carl, et al.
(författare)
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Neutron noise measurements in the YALINA-Booster experiments
- 2009
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Ingår i: Proceedings of International Topical Meeting on Nuclear Research Applications and Utilization of Accelerators. - : International Atomic Energy Agency. - 9789201504104
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Konferensbidrag (refereegranskat)abstract
- In addition to the pulsed neutron source measurements and the continuous source beam-trip and current-to-flux measurements performed in the YALINA-Booster facility, also presented in this conference, a set of neutron noise measurements has been performed to achieve a complete characterization of the core. The neutron noise measurements have been performed in three different configurations covering a subcriticality range from 0.85 to 0.977. The Rossi-α neutron noise technique has been applied to detector counts from two channels in the thermal part of the core. The Rossi-α results are compared to the experimental prompt neutron decay constants obtained from the pulsed neutron source measurements. A first approach fitting procedure reveals a need of three exponentials to describe the Rossi-α histograms. It has been found that at deep subcriticality, the fundamental mode decay may coincide with or be close to a higher eigenmode, thus making it difficult to determine the prompt neutron decay constant correctly.
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| 6. |
- Berglöf, Carl, et al.
(författare)
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Pulsed neutron source reference measurements in the subcritical experiment YALINA-Booster
- 2009
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Ingår i: Proceedings of International Topical Meeting on Nuclear Research Applications and Utilization of Accelerators. - : International Atomic Energy Agency. - 9789201504104
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Konferensbidrag (refereegranskat)abstract
- In support of an online reactivity monitoring experiment, also presented in this conference, this work presents the reactivity calibration measurements performed with a pulsed neutron source in the coupled fast-thermal subcritical facility YALINA-Booster. These experiments reveal the complexity of experimentally obtaining a global reactivity from a highly heterogeneous core. Moreover, the effect of varying the source multiplication at constant reactivity on the area ratio technique is explored. It is found that the reactivity obtained with the area ratio technique carry strong spatial dependence, but it can be handled by calculated correction factors. On the other hand the method is showed not to be sensitive to changes in the source multiplication. It is also shown that the prompt neutron decay constant does not vary strongly over the core except at deep subcritical states.
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| 7. |
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| 8. |
- Bryukhovetskiy, Andrey S., et al.
(författare)
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Human mind has microwave electromagnetic nature and can be recorded and processed
- 2020
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Ingår i: Neuropharmacology of Neuroprotection. - : ELSEVIER. - 9780128208137 ; , s. 439-463
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Bokkapitel (refereegranskat)abstract
- Introduction: In 2014 and 2015 Professor of neurology Andrey Bryukhovetskiy published a novel theory of the information-commutation organization of the human brain in Russia, China and the USA. The theory posits the hypothesis that the higher nervous activity (cognitive, intellectual, mnestic) of the humans and their mind are material and have microwave electromagnetic nature. The theory perceives the human mind as a result of dynamic extracortical information-commutation relations of the super-positions of the electromagnetic waves of ultra high frequency emitted by different areas of the human brain in the inter-membrane cerebrospinal fluid space of the human head at a certain period of time. The inter-membrane cerebrospinal fluid space of the human head (the space between the dura, arachnoid and pia mater filled with the cerebrospinal fluid) of about 10mm size, has all morphological attributes to realize the holography. It is a universal natural bioprocessor for processing, analysis and synthesis of the input data and their record or reproduction on the pia as on the biological holographic membrane. The theory suggested that the processes of the mind can be recorded and digitalized with the last generation contemporary microwave receptors of the UHF band. Goal: The goal is to experimentally test the theory of the information-commutation organization of the human brain, particularly, the postulate that the human mind has material, and, namely, electromagnetic nature represented by the microwave bioelectric activity; it must be detected, recorded and statistically processed, i.e. its existence must be confirmed. Methods: On their own initiative, the team of mathematicians, radioengineers and neurologists performed the non-invasive research of the electromagnetic radiation of human brain in the broad frequency range varying from 850MHz to 26.5GHz with the last generation specialized measuring equipment with high sensitivity and recording speed, specialized measuring antennas and low noise amplifying equipment in the anechoic chamber of the 1st class of protection according to the Russian system of certification GOST R 50414-92. Results: The previously unknown microwave electromagnetic radiation of the EHF/UHF range (from 1.5GHz to 4.5GHz) with signal strength of -130dBm .. -100dBm (1e(-15) .. 1e(-13) W) are discovered. The detected electromagnetic waves have zonal variations in the different areas of the human head and are absent in other areas of the human body. The method of recording of the microwave electromagnetic activity of the human brain is patented in the Russian Federation. The microwave electromagnetic activity of the brain is billion-fold different from the bioelectric activity recorded by the encephalography. Conclusion: Discovery of the phenomenon of the microwave radiation of the human brain provides evidence to the idea that thinking and mind are material. This phenomenon has the potential to become a new informational channel of the diagnostics of the functional and pathological state of the higher nervous activity of the human brain. It can provide the basis for the development of the equipment for real-time analysis of the microwave bioelectric activity of the brain in norm and pathology, for objective early diagnostics of the functional and emotional conditions as well as of the psychiatric disorders at the preclinical stage, for the biocontrol of the human brain and the artificial simulators of the human brain. It also can provide the foundation for new systems of the artificial intellect, brain-computer interface and systems of the closed-loop biomanagement of the damaged brain.
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| 9. |
- Persson, C. -M, et al.
(författare)
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Comparison of neutron kinetic parameters of the subcritical ads experiments Yalina and Yalina Booster
- 2005
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Konferensbidrag (refereegranskat)abstract
- Subcritical experiments, devoted to investigation of characteristics of accelerator-driven systems, have been constructed at the Joint Institute for Power and Nuclear Research - Sosny in Minsk, Belarus. Different methods for reactivity determination have previously been investigated in the thermal ADS experiment "Yalina", and recently, a coupled fast-thermal facility "Yalina Booster" was launched. This study presents the neutron kinetic characteristics of the Yalina and the new Yalina Booster setups, and points out some important differences. For the Yalina setup, neutron kinetic parameters, such as keff, α, βeff and Λ have been determined by Monte Carlo simulations and they have previously been verified experimentally. For Yalina Booster, these parameters have been estimated by Monte Carlo simulations in a preliminary study, and they will be verified in upcoming experiments.
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| 10. |
- Persson, Carl-Magnus, et al.
(författare)
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Results from pulsed neutron source measurements in the YALINA-Booster ads experiment
- 2007
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Ingår i: 8th International Topical Meeting on Nuclear Applications and Utilization of Accelerators, ACCAPP'07. - 0894480545 - 9780894480546 ; , s. 924-929
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Konferensbidrag (refereegranskat)abstract
- Two subcritical configurations of the zero-power coupled subcritical core YALINA-Booster have been identified through pulsed neutron source measurements. The area ratio and the slope fitting reactivity estimation methods have been utilized as well as the pulsed Rossi-a noise method. The measurements showed that despite the inhomogeneous two-zone core composition a clear single exponential prompt neutron decay was obtained. Spatial spread of the results and converegence issues related to the area ratio method are addressed.
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| 11. |
- Serafimovich, Natalia I., 1974-, et al.
(författare)
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Optical observations of the young supernova remnant SNR 0540-69.3 and its pulsar
- 2005
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Ingår i: Advances in Space Research. - : Elsevier BV. - 0273-1177 .- 1879-1948. ; 35:6, s. 1106-1111
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Tidskriftsartikel (refereegranskat)abstract
- We have used the ESO NTT/EMMI and VLT/FORS1 instruments to examine the LMC supernova remnant 0540-69.3 as well as its pulsar (PSR B0540-69) and pulsar-powered nebula in the optical range. Spectroscopic observations of the remnant covering the range of 3600 7350 Å centered on the pulsar produced results consistent with those of [Kirshner, R.P., Morse, J.A., Winkler, P.F., et al. The penultimate supernova in the Large Magellanic Cloud - SNR 0540-69.3. Astrophys.J. 342, 260 271, 1989.] but also revealed many new emission lines. The most important are [Ne III] λλ3869, 3967 and Balmer lines of hydrogen. In both the central part of the remnant, as well as in nearby H II regions, the [O III] temperature is higher than ˜2 × 104 K, but lower than previously estimated. For PSR B0540-69, previous optical data are mutually inconsistent: HST/FOS spectra indicate a significantly higher absolute flux and steeper spectral index than suggested by early time-resolved groundbased UBVRI photometry. We show that the HST and VLT spectroscopic data for the pulsar have ≳50% nebular contamination, and that this is the reason for the previous difference. Using HST/WFPC2 archival images obtained in various bands from the red part of the optical to the NUV range we have performed an accurate photometric study of the pulsar, and find that the spectral energy distribution of the pulsar emission has a negative slope with α=1.07-0.19+0.20. This is steeper than derived from previous UBVRI photometry, and also different from the almost flat spectrum of the Crab pulsar. We also estimate that the proper motion of the pulsar is 4.9 ± 2.3 mas year‑1, corresponding to a transverse velocity of 1190 ± 560 km s‑1, projected along the southern jet of the pulsar nebula.
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| 12. |
- Serafimovich, Natalia I., 1974-, et al.
(författare)
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The young pulsar PSR B0540-69.3 and its synchrotron nebula in the optical and X-rays
- 2004
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 425:3, s. 1041-1060
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Tidskriftsartikel (refereegranskat)abstract
- The young PSR B0540-69.3 in the LMC is the only pulsar (except the Crab pulsar) for which a near-UV spectrum has been obtained. However, the absolute flux and spectral index of the HST/FOS spectrum are significantly higher than suggested by previous broad-band time-resolved groundbased UBVRI photometry. To investigate this difference, observations with ESO/VLT/FORS1 and analysis of HST/WFPC2 archival data were done. We show that the HST and VLT spectral data for the pulsar have ⪆50% nebular contamination and that this is the reason for the above-mentioned difference. The broadband HST spectrum for the range 3300-8000 Å is clearly nonthermal and has a negative spectral index, Fν ∝ ν-α with αν = 1.07+0.20-0.19. This is different from the almost flat spectrum of the Crab pulsar, and also steeper than for the previously published broadband photometry of PSR B0540-69.3. We have also studied the spatial variations of the brightness and spectral index of the Pulsar Wind Nebula (PWN) around the pulsar, and find no significant spectral index variation over the PWN. The HST data show a clear asymmetry of the surface brightness distribution along the major axis of the torus-like structure of the PWN with respect to the pulsar position, also seen in Chandra/HRC X-ray images. This is different from the Crab PWN and likely linked to the asymmetry of the surrounding SN ejecta. The HST/WFPC2 archival data have an epoch separation of 4 years, and this allows us to estimate the proper motion of the pulsar. We find a motion of 4.9±2.3 mas yr-1 (corresponding to a transverse velocity of 1190±560 km s-1) along the southern jet of the PWN. If this is confirmed at a higher significance level by future observations, this makes PSR B0540-69.3 the third pulsar with a proper motion aligned with the jet axis of its PWN, which poses constraints on pulsar kick models. To establish the multiwavelength spectrum of the pulsar and its PWN, we have included recent Chandra X-ray data, and discuss the soft pulsar X-ray spectrum based on spectral fits including absorption by interstellar gas in the Milky Way, LMC as well as the supernova ejecta. We have compared the multiwavelength spectra of PSR B0540-69.3 and the Crab pulsar, and find that both PSR B0540-69.3 and the Crab pulsar have a weaker flux in the optical than suggested by a low-energy power-law extension of the X-ray spectrum. This optical depression is more severe for PSR B0540-69.3 than for the Crab pulsar. The same trend is seen for the PWNe of the two pulsars, and continues for low energies also out in the radio band. We discuss possible interpretations of this behavior. Based on observations performed at the European Southern Observatory, Paranal, Chile (ESO Program 67.D-0519).
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