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V. I. Nazaruk - One of the best experts on this subject based on the ideXlab platform.
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Limit on the neutron-antineutron transitions in the alternative models
arXiv: Nuclear Theory, 2013Co-Authors: V. I. NazarukAbstract:We summarize our study of the neutron-antineutron transition in medium and nuclei in the framework of the field-theoretical approach. The models based on the diagram technique for direct reactions, potential description of antineutron-medium interaction are considered as well. The lower limit on the free-space neutron-antineutron Oscillation Time $\tau $ is in the range: $10^{16}\; {\rm yr}>\tau >1.2\cdot 10^{9}\; {\rm s}$.
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ALTERNATIVE MODELS OF NEUTRON–ANTINEUTRON CONVERSION IN NUCLEI
International Journal of Modern Physics E-nuclear Physics, 2012Co-Authors: V. I. NazarukAbstract:The models of the transition in medium and nuclei based on the diagram technique for direct reactions, potential description of -medium interaction and field-theoretical approach are considered. It is shown that for the transition in medium field-theoretical approach should be used. The lower limit on the free-space Oscillation Time τ is in the range: 1016yr>τ>1.2⋅109s.
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ON THE SUPPRESSION OF THE $n\bar{n}$ TRANSITIONS IN MEDIUM
International Journal of Modern Physics E, 2011Co-Authors: V. I. NazarukAbstract:The model of transitions in the medium based on field-theoretical approach is considered. The Time-dependence and corrections to the model are studied. The lower limit on the free-space Oscillation Time τ is in the range 1016yr>τ>1.2×109s.
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$n\bar{n}$ transitions in medium
arXiv: Nuclear Theory, 2009Co-Authors: V. I. NazarukAbstract:The models of $n\bar{n}$ transitions in the medium based on unitary $S$-matrix are considered. The Time-dependence and corrections to the models are studied. The lower limits on the free-space $n\bar{n}$ Oscillation Time are obtained as well.
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Cause of Disparity between the Results for the $n\bar{n}$ Transition Problem
arXiv: High Energy Physics - Phenomenology, 1996Co-Authors: V. I. NazarukAbstract:We show that there is a double counting in the standard model of $n\bar{n}$ mixing in the medium, resulting in full cancellation of leading terms. The direct calculation of $n\bar{n}$ transition, annihilation is performed. For lower limit on the free-space $n\bar{n}$ Oscillation Time we get $\tau_{min} \sim 10^{31}y$.
A. N. Murashkin - One of the best experts on this subject based on the ideXlab platform.
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Search for neutron–mirror neutron Oscillations in a laboratory experiment with ultracold neutrons
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2009Co-Authors: A. P. Serebrov, E. B. Aleksandrov, N. A. Dovator, S. P. Dmitriev, A. K. Fomin, P. Geltenbort, A. G. Kharitonov, I. A. Krasnoschekova, M. S. Lasakov, A. N. MurashkinAbstract:Abstract Mirror matter is considered as a candidate for dark matter. In connection with this an experimental search for neutron–mirror neutron (nn′) transitions has been carried out using storage of ultracold neutrons in a trap with different magnetic fields. As a result, a new limit for the neutron–mirror neutron Oscillation Time τ osc has been obtained, τ osc ≥448 s (90% C.L.), assuming that there is no mirror magnetic field larger than 100 nT. Besides a first attempt to obtain some restriction for mirror magnetic field has been done.
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Search for neutron–mirror neutron Oscillations in a laboratory experiment with ultracold neutrons
Nuclear Instruments and Methods in Physics Research Section A: Accelerators Spectrometers Detectors and Associated Equipment, 2009Co-Authors: A. P. Serebrov, E. B. Aleksandrov, N. A. Dovator, S. P. Dmitriev, A. K. Fomin, P. Geltenbort, A. G. Kharitonov, I. A. Krasnoschekova, M. S. Lasakov, A. N. MurashkinAbstract:Mirror matter is considered as a candidate for dark matter. In connection with this an experimental search for neutron - mirror neutron (nn') transitions has been carried out using storage of ultracold neutrons in a trap with different magnetic fields. As a result, a new limit for the neutron - mirror neutron Oscillation Time has been obtained, tau_osc >= 448 s (90% C.L.), assuming that there is no mirror magnetic field larger than 100 nT. Besides a first attempt to obtain some restriction for mirror magnetic field has been done.Comment: 11 pages, more detailed analysis of dat
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Experimental search for neutron-mirror neutron Oscillations using storage of ultracold neutrons
Physics Letters B, 2008Co-Authors: A. P. Serebrov, E. B. Aleksandrov, N. A. Dovator, S. P. Dmitriev, A. K. Fomin, P. Geltenbort, A. G. Kharitonov, I. A. Krasnoschekova, M. S. Lasakov, A. N. MurashkinAbstract:Abstract The idea of a hidden sector of mirror partners of elementary particles has attracted considerable interest as a possible candidate for dark matter. Recently it was pointed out by Berezhiani and Bento that the present experimental data cannot exclude the possibility of a rapid Oscillation of the neutron n to a mirror neutron n′ with Oscillation Time much smaller than the neutron lifeTime. A dedicated search for vacuum transitions n → n ′ has to be performed at weak magnetic field, where both states are degenerate. We report the result of our experiment, which compares rates of ultracold neutrons after storage at a weak magnetic field well below 20 nT and at a magnetic field strong enough to suppress the seeked transitions. We obtain a new limit for the Oscillation Time of n–n′ transitions, τ osc ( 90 % C.L. ) > 414 s . The corresponding limit for the mixing energy of the normal and mirror neutron states is δ m ( 90 % C.L. ) 1.5 × 10 −18 eV .
Gang Liu - One of the best experts on this subject based on the ideXlab platform.
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A Novel Autonomous Celestial Navigation Method Using Solar Oscillation Time Delay Measurement
IEEE Transactions on Aerospace and Electronic Systems, 2018Co-Authors: Xiaolin Ning, Mingzhen Gui, Jiancheng Fang, Gang Liu, Wu WeirenAbstract:Solar Oscillations cause significant variations in sunlight spectral wavelength and intensity over short Time periods. These Oscillations have been studied in detail over the years, both theoretically and using actual observations. Through detecting the sunlight spectral central wavelengths and intensity and recording the moment when solar Oscillation occurs, the Time delay between the sunlight coming from the Sun directly and the sunlight reflected by a celestial body such as the satellite of a planet or asteroid can be obtained. Because the solar Oscillation Time delay is determined by the relative positions of the spacecraft, the reflective celestial body, and the Sun, it can be adopted as the navigation measurement to provide the spacecraft's position information. In this paper, a novel celestial navigation method using the solar Oscillation Time delay measurement is proposed. The implicit measurement model of Time delay is built, and the implicit unscented Kalman filter is applied. Simulation results indicate that the position error and velocity error of the proposed method for the transfer orbit are about 3.55 km and 0.077 m/s, respectively, and those for the surrounding orbit are about 1.76 km and 1.57 m/s, respectively. The impact of four factors on the navigation performance is also investigated.
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Solar Oscillation Time delay measurement assisted celestial navigation method
Acta Astronautica, 2017Co-Authors: Xiaolin Ning, Mingzhen Gui, Jie Zhang, Jiancheng Fang, Gang LiuAbstract:Abstract Solar Oscillation, which causes the sunlight intensity and spectrum frequency change, has been studied in great detail, both observationally and theoretically. In this paper, owing to the existence of solar Oscillation, the Time delay between the sunlight coming from the Sun directly and the sunlight reflected by the other celestial body such as the satellite of planet or asteroid can be obtained with two optical power meters. Because the solar Oscillation Time delay is determined by the relative positions of the spacecraft, reflective celestial body and the Sun, it can be adopted as the navigation measurement to estimate the spacecraft's position. The navigation accuracy of single solar Oscillation Time delay navigation system depends on the Time delay measurement accuracy, and is influenced by the distance between spacecraft and reflective celestial body. In this paper, we combine it with the star angle measurement and propose a solar Oscillation Time delay measurement assisted celestial navigation method for deep space exploration. Since the measurement model of Time delay is an implicit function, the Implicit Unscented Kalman Filter (IUKF) is applied. Simulations demonstrate the effectiveness and superiority of this method.
Xiaolin Ning - One of the best experts on this subject based on the ideXlab platform.
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A Novel Autonomous Celestial Navigation Method Using Solar Oscillation Time Delay Measurement
IEEE Transactions on Aerospace and Electronic Systems, 2018Co-Authors: Xiaolin Ning, Mingzhen Gui, Jiancheng Fang, Gang Liu, Wu WeirenAbstract:Solar Oscillations cause significant variations in sunlight spectral wavelength and intensity over short Time periods. These Oscillations have been studied in detail over the years, both theoretically and using actual observations. Through detecting the sunlight spectral central wavelengths and intensity and recording the moment when solar Oscillation occurs, the Time delay between the sunlight coming from the Sun directly and the sunlight reflected by a celestial body such as the satellite of a planet or asteroid can be obtained. Because the solar Oscillation Time delay is determined by the relative positions of the spacecraft, the reflective celestial body, and the Sun, it can be adopted as the navigation measurement to provide the spacecraft's position information. In this paper, a novel celestial navigation method using the solar Oscillation Time delay measurement is proposed. The implicit measurement model of Time delay is built, and the implicit unscented Kalman filter is applied. Simulation results indicate that the position error and velocity error of the proposed method for the transfer orbit are about 3.55 km and 0.077 m/s, respectively, and those for the surrounding orbit are about 1.76 km and 1.57 m/s, respectively. The impact of four factors on the navigation performance is also investigated.
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Solar Oscillation Time delay measurement assisted celestial navigation method
Acta Astronautica, 2017Co-Authors: Xiaolin Ning, Mingzhen Gui, Jie Zhang, Jiancheng Fang, Gang LiuAbstract:Abstract Solar Oscillation, which causes the sunlight intensity and spectrum frequency change, has been studied in great detail, both observationally and theoretically. In this paper, owing to the existence of solar Oscillation, the Time delay between the sunlight coming from the Sun directly and the sunlight reflected by the other celestial body such as the satellite of planet or asteroid can be obtained with two optical power meters. Because the solar Oscillation Time delay is determined by the relative positions of the spacecraft, reflective celestial body and the Sun, it can be adopted as the navigation measurement to estimate the spacecraft's position. The navigation accuracy of single solar Oscillation Time delay navigation system depends on the Time delay measurement accuracy, and is influenced by the distance between spacecraft and reflective celestial body. In this paper, we combine it with the star angle measurement and propose a solar Oscillation Time delay measurement assisted celestial navigation method for deep space exploration. Since the measurement model of Time delay is an implicit function, the Implicit Unscented Kalman Filter (IUKF) is applied. Simulations demonstrate the effectiveness and superiority of this method.
P. Geltenbort - One of the best experts on this subject based on the ideXlab platform.
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Search for neutron–mirror neutron Oscillations in a laboratory experiment with ultracold neutrons
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2009Co-Authors: A. P. Serebrov, E. B. Aleksandrov, N. A. Dovator, S. P. Dmitriev, A. K. Fomin, P. Geltenbort, A. G. Kharitonov, I. A. Krasnoschekova, M. S. Lasakov, A. N. MurashkinAbstract:Abstract Mirror matter is considered as a candidate for dark matter. In connection with this an experimental search for neutron–mirror neutron (nn′) transitions has been carried out using storage of ultracold neutrons in a trap with different magnetic fields. As a result, a new limit for the neutron–mirror neutron Oscillation Time τ osc has been obtained, τ osc ≥448 s (90% C.L.), assuming that there is no mirror magnetic field larger than 100 nT. Besides a first attempt to obtain some restriction for mirror magnetic field has been done.
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Search for neutron–mirror neutron Oscillations in a laboratory experiment with ultracold neutrons
Nuclear Instruments and Methods in Physics Research Section A: Accelerators Spectrometers Detectors and Associated Equipment, 2009Co-Authors: A. P. Serebrov, E. B. Aleksandrov, N. A. Dovator, S. P. Dmitriev, A. K. Fomin, P. Geltenbort, A. G. Kharitonov, I. A. Krasnoschekova, M. S. Lasakov, A. N. MurashkinAbstract:Mirror matter is considered as a candidate for dark matter. In connection with this an experimental search for neutron - mirror neutron (nn') transitions has been carried out using storage of ultracold neutrons in a trap with different magnetic fields. As a result, a new limit for the neutron - mirror neutron Oscillation Time has been obtained, tau_osc >= 448 s (90% C.L.), assuming that there is no mirror magnetic field larger than 100 nT. Besides a first attempt to obtain some restriction for mirror magnetic field has been done.Comment: 11 pages, more detailed analysis of dat
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Neutron to mirror-neutron Oscillations in the presence of mirror magnetic fields
Physical Review D, 2009Co-Authors: I. Altarev, P. Geltenbort, K. Green, C.a. Baker, G. Ban, K. Bodek, M. Daum, P. Fierlinger, M. G. D. Van Der Grinten, E. GutsmiedlAbstract:We performed ultracold neutron (UCN) storage measurements to search for additional losses due to neutron (n) to mirror-neutron (n') Oscillations as a function of an applied magnetic field B. In the presence of a mirror magnetic field B', UCN losses would be maximal for B = B'. We did not observe any indication for nn' Oscillations and placed a lower limit on the Oscillation Time of tau_{nn'} > 12.0 s at 95% C.L. for any B' between 0 and 12.5 uT.
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Experimental search for neutron-mirror neutron Oscillations using storage of ultracold neutrons
Physics Letters B, 2008Co-Authors: A. P. Serebrov, E. B. Aleksandrov, N. A. Dovator, S. P. Dmitriev, A. K. Fomin, P. Geltenbort, A. G. Kharitonov, I. A. Krasnoschekova, M. S. Lasakov, A. N. MurashkinAbstract:Abstract The idea of a hidden sector of mirror partners of elementary particles has attracted considerable interest as a possible candidate for dark matter. Recently it was pointed out by Berezhiani and Bento that the present experimental data cannot exclude the possibility of a rapid Oscillation of the neutron n to a mirror neutron n′ with Oscillation Time much smaller than the neutron lifeTime. A dedicated search for vacuum transitions n → n ′ has to be performed at weak magnetic field, where both states are degenerate. We report the result of our experiment, which compares rates of ultracold neutrons after storage at a weak magnetic field well below 20 nT and at a magnetic field strong enough to suppress the seeked transitions. We obtain a new limit for the Oscillation Time of n–n′ transitions, τ osc ( 90 % C.L. ) > 414 s . The corresponding limit for the mixing energy of the normal and mirror neutron states is δ m ( 90 % C.L. ) 1.5 × 10 −18 eV .