Search

Your search keyword '"Mitrofanov, I. G."' showing total 520 results
Start Over Author "Mitrofanov, I. G."
520 results on '"Mitrofanov, I. G."'

51. The Direct Test of Cosmological Model for Cosmic Gamma-Ray Bursts Based on the Peak Alignment Averaging

Author

Mitrofanov, I. G., Litvak, M. L., and Ushakov, D. A.

Subjects
Astrophysics
Abstract

The cosmological origin of cosmic gamma-ray bursts is tested using the method of peak alignment for the averaging of time profiles. The test is applied to the basic cosmological model with standard sources, which postulates that difference between bright and dim bursts results from different cosmological red-shifts of their sources. The average emissivity curve (ACEbright) of the group of bright BATSE bursts is approximated by a simple analytical function, which takes into account the effect of squeezing of the time pulses with increasing energy of photons. This function is used to build the model light curve for ACEdim of dim BATSE bursts, which takes into account both the cosmological time- stretching of bursts light curves and the red-shifting of photons energies. Direct comparison between the model light curve and the ACEdim of dim bursts is performed, which is based on the estimated probabilities of differences between ACEs of randomly selected groups of bursts. It shows no evidence for the predicted cosmological effects. The 3 sigma upper limit of the average red- shift Zdim of emitters of dim bursts is estimated to be as small, as 0.1-0.5, which is not consistent with values 1 predicted by the known cosmological models of gamma-ray bursts., Comment: 25 pages, Latex, 7 Postscript figures, uses aasms4.sty accepted to ApJ 19.06.97

Published
1997
Full Text
View/download PDF

65. Estimation of the Neutron Component of the Radiation Background in the Gale Crater on Mars.

Author

Mitrofanov, I. G., Litvak, M. L., Sanin, A. B., Semkova, I. V., and Dachev, Ts. P.

Subjects
*GALE Crater (Mars), *BACKGROUND radiation, *GALACTIC cosmic rays, *NEUTRONS, *MARS rovers, *RADIATION protection, *COSMIC rays
Abstract

The paper presents the results of the analysis of the neutron component of the radiation background on Mars in the Gale crater, where the NASA Curiosity rover conducts its research. Numerical estimates have shown that the effective dose rate for neutrons at the maximum flux of galactic cosmic rays varies along the rover path by 20% in the range of 92–108 μSv/day. This variation is mainly driven by the variable content of subsurface water, which ranges from 0.5 to 5% mass fraction along the rover path. The estimates obtained are comparable with the measurements of the RAD radiation dosimeter. The comparison with doses from charged particles shows that the contribution of the neutron component on the surface of Mars to the total dose with no radiation protection is 10%, which should be taken into account when planning manned missions to Mars. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

70. Test facility for nuclear planetology instruments

Author

Vostrukhin, A. A., Golovin, D. V., Dubasov, P. V., Zontikov, A. O., Kozyrev, A. S., Krylov, A. R., Krylov, V. A., Litvak, M. L., Malakhov, A. V., Mitrofanov, I. G., Mokrousov, M. I., Ponomarev, I. D., Repkin, A. N., Sanin, A. B., Timoshenko, G. N., Udovichenko, K. V., and Shvetsov, V. N.

Published
2016
Full Text
View/download PDF

72. 2001 Mars Odyssey Mission Summary

Author

Saunders, R. S., Arvidson, R. E., Badhwar, G. D., Boynton, W. V., Christensen, P. R., Cucinotta, F. A., Feldman, W. C., Gibbs, R. G., Kloss, C., Jr., Landano, M. R., Mase, R. A., Mcsmith, G. W., Meyer, M. A., Mitrofanov, I. G., Pace, G. D., Plaut, J. J., Sidney, W. P., Spencer, D. A., Thompson, T. W., Zeitlin, C. J., and Russell, Christopher T., editor

Published
2004
Full Text
View/download PDF

73. The Mars Odyssey Gamma-Ray Spectrometer Instrument Suite

Author

Boynton, W. V., Feldman, W. C., Mitrofanov, I. G., Evans, L. G., Reedy, R. C., Squyres, S. W., Starr, R., Trombka, J. I., D’uston, C., Arnold, J. R., Englert, P. A. J., Metzger, A. E., Wänke, H., Brückner, J., Drake, D. M., Shinohara, C., Fellows, C., Hamara, D. K., Harshman, K., Kerry, K., Turner, C., Ward, M., Barthe, H., Fuller, K. R., Storms, S. A., Thornton, G. W., Longmire, J. L., Litvak, M. L., Ton’chev, A. K., and Russell, Christopher T., editor

Published
2004
Full Text
View/download PDF

76. Hydrogen Mapping of the Lunar South Pole Using the LRO Neutron Detector Experiment LEND

Author

Mitrofanov, I. G., Sanin, A. B., Boynton, W. V., Chin, G., Garvin, J. B., Golovin, D., Evans, L. G., Harshman, K., Kozyrev, A. S., Litvak, M. L., Malakhov, A., Mazarico, E., McClanahan, T., Milikh, G., Mokrousov, M., Nandikotkur, G., Neumann, G. A., Nuzhdin, I., Sagdeev, R., Shevchenko, V., Shvetsov, V., Smith, D. E., Starr, R., Tretyakov, V. I., Trombka, J., Usikov, D., Varenikov, A., Vostrukhin, A., and Zuber, M. T.

Published
2010

77. The Interplanetary Network Response to LIGO GW150914

Author

Hurley, K, Svinkin, D. S, Aptekar, R.L, Golenetskii, S. V, Frederiks, D. D, Boynton, W, Mitrofanov, I. G, Golovin, D. V, Kozyrev, A. S, Litvak, M. L, Sanin, A. B, Rau, A, Kienlin, A. Von, Zhang, X, Connaughton, V, Meegan, C, Cline, Thomas L, and Gehrels, Cornelis

Subjects
Astrophysics
Abstract

We have performed a blind search for a gamma-ray transient of arbitrary duration and energy spectrum around the time of the LIGO gravitational-wave event GW150914 with the six-spacecraft interplanetary network (IPN). Four gamma-ray bursts were detected between 30 hr prior to the event and 6.1 hr after it, but none could convincingly be associated with GW150914. No other transients were detected down to limiting 15-150 keV fluences of roughly 5 x 10(exp -8) -5 x 10(exp -7) erg cm(exp -2). We discuss the search strategies and temporal coverage of the IPN on the day of the event and compare the spatial coverage to the region where GW150914 originated. We also report the negative result of a targeted search for the Fermi-GBM event reported in conjunction with GW150914.

Published
2016
Full Text
View/download PDF

78. Hydrogen Distribution in the Lunar Polar Regions

Author

Sanin, A. B, Mitrofanov, I. G, Litvak, M. L, Bakhtin, B. N, Bodnarik, J. G, Boynton, W. V, Chin, G, Evans, L. G, Harshmann, K, Fedosov, F, and McClanaham, T. P

Subjects
Lunar And Planetary Science And Exploration
Abstract

We present a method of conversion of the lunar neutron counting rate measured by the Lunar Reconnaissance Orbiter (LRO) Lunar Exploration Neutron Detector (LEND) instrument collimated neutron detectors, to water equivalent hydrogen (WEH) in the top approximately 1 m layer of lunar regolith. Polar maps of the Moon’s inferred hydrogen abundance are presented and discussed.

Published
2016
Full Text
View/download PDF

79. The Variations of Neutron Component of Lunar Radiation Background from LEND LRO Observations

Author

Litvak, M. L, Mitrofanov, I. G, Sanin, A. B, Bakhtin, B. N, Bodnarik, J. G, Bodnarik, W. V, Chin, G, Evans, L.G, Harshman, K, Livengood, T. A, Malakhov, A, Mokrousov, M. I, McClanahan, T. P, Sagdeev, R, and Starr, R

Subjects
Astrophysics
Abstract

Lunar neutron flux data measured by the Lunar Exploration Neutron Detector (LEND) on board NASA's Lunar Reconnaissance Orbiter (LRO) were analyzed for the period 2009-2014.We have re-evaluated the instrument's collimation capability and re-estimated the neutron counting rate measured in the Field of View (FOV) of the LEND collimated detectors, and found it to be 1.070.1counts per second. We derived the spectral density of the neutron flux for various lunar regions using our comprehensive numerical model of orbital measurements. This model takes into account the location of the LEND instrument onboard LRO to calculate the surface leakage neutron flux and its propagation to the instrument detectors. Based on this we have determined the lunar neutron flux at the surface to be approx. 2 neutrons/ [sq cm/ sec] in the epithermal energy range, 0.4e V to 1keV. We have also found variations of the lunar neutron leakage flux with amplitude as large as a factor of two, by using multi-year observations to explore variations in the Galactic Cosmic Ray (GCR) flux during the 23rd-24th solar cycles.

Published
2016
Full Text
View/download PDF

80. Evidence for the Sequestration of Hydrogen-Bearing Volatiles Towards the Moons Southern Pole-Facing Slopes

Author

McClanahan, T. P, Mitrofanov, I. G, Boynton, W. V, Chin, G, Bodnarik, J, Droege, G, Evans, L. G, Golovin, D, Hamara, D, Harshman, K, Litvak, M, Livengood, T. A, Malakhov, A, Mazarico, E, Milikh, G, Nandikotkur, G, Parsons, A, Sagdeev, R, Sanin, A, Starr, R. D, Su, J. J, and Murray, J

Subjects
Lunar And Planetary Science And Exploration
Abstract

The Lunar Exploration Neutron Detector (LEND) onboard the Lunar Reconnaissance Orbiter (LRO) detects a widespread suppression of the epithermal neutron leakage flux that is coincident with the pole-facing slopes (PFS) of the Moon's southern hemisphere. Suppression of the epithermal neutron flux is consistent with an interpretation of enhanced concentrations of hydrogen-bearing volatiles within the upper meter of the regolith. Localized flux suppression in PFS suggests that the reduced solar irradiation and lowered temperature on PFS constrains volatility to a greater extent than in surrounding regions. Epithermal neutron flux mapped with LEND's Collimated Sensor for Epithermal Neutrons (CSETN) was analyzed as a function of slope geomorphology derived from the Lunar Orbiting Laser Altimeter (LOLA) and the results compared to co-registered maps of diurnally averaged temperature from the Diviner Lunar Radiometer Experiment and an averaged illumination map derived from LOLA. The suppression in the average south polar epithermal neutron flux on equator-facing slopes (EFS) and PFS (85-90 deg S) is 3.3 +/- 0.04% and 4.3 +/- 0.05% respectively (one-sigma-uncertainties), relative to the average count-rate in the latitude band 45-90 deg S. The discrepancy of 1.0 +/- 0.06% between EFS and PFS neutron flux corresponds to an average of approximately 23 parts-per-million-by-weight (ppmw) more hydrogen on PFS than on EFS. Results show that the detection of hydrogen concentrations on PFS is dependent on their spatial scale. Epithermal flux suppression on large scale PFS was found to be enhanced to 5.2 +/- 0.13%, a discrepancy of approximately 45 ppmw hydrogen relative to equivalent EFS. Enhanced poleward hydration of PFS begins between 50 deg S and 60 deg S latitude. Polar regolith temperature contrasts do not explain the suppression of epithermal neutrons on pole-facing slopes. The Supplemental on-line materials include supporting results derived from the uncollimated Lunar Prospector Neutron Spectrometer and the LEND Sensor for Epithermal Neutrons.

Published
2015

81. Epithermal Neutron Evidence for a Diurnal Surface Hydration Process in the Moon's High Latitudes

Author

McClanahan, T. P, Mitrofanov, I. G, Boynton, W. V, Chin, G, Parsons, A, Starr, R. D, Evans, L. G, Sanin, A, Litvak, M, and Livengood, T

Subjects
Physics Of Elementary Particles And Fields, Lunar And Planetary Science And Exploration
Abstract

We report evidence from epithermal neutron flux observations that show that the Moon's high latitude surfaces are being actively hydrated, dehydrated and rehydrated in a diurnal cycle. The near-surface hydration is indicated by an enhanced suppression of the lunar epithermal neutron leakage flux on the dayside of the dawn terminator on poleward-facing slopes (PFS). At 0600 to 0800 local-time, hydrogen concentrations within the upper 1 meter of PFS are observed to be maximized relative to equivalent equator-facing slopes (EFS). During the lunar day surface hydrogen concentrations diminish towards dusk and then rebuild overnight. Surface hydration is determined by differential comparison of the averaged EFS to PFS epithermal neutron count rates above +/- 75 deg latitude. At dawn the contrast bias towards PFS is consistent with at least 15 to 25 parts-per-million (ppm) hydrogen that dissipates by dusk. We review several lines of evidence derived from temperature and epithermal neutron data by a correlated analysis of observations from the Lunar Reconnaissance Orbiter's (LRO) Lunar Exploration Neutron Detector (LEND) that were mapped as a function of lunar local-time, Lunar Observing Laser Altimeter (LOLA) topography and Diviner (DLRE) surface temperature.

Published
2015

83. Dynamic Albedo of Neutrons (DAN) Experiment Onboard NASA’s Mars Science Laboratory

Author

Mitrofanov, I. G., Litvak, M. L., Varenikov, A. B., Barmakov, Y. N., Behar, A., Bobrovnitsky, Y. I., Bogolubov, E. P., Boynton, W. V., Harshman, K., Kan, E., Kozyrev, A. S., Kuzmin, R. O., Malakhov, A. V., Mokrousov, M. I., Ponomareva, S. N., Ryzhkov, V. I., Sanin, A. B., Smirnov, G. A., Shvetsov, V. N., Timoshenko, G. N., Tomilina, T. M., Tret’yakov, V. I., and Vostrukhin, A. A.

Published
2012
Full Text
View/download PDF

87. The first stage of the “BTN-Neutron” space experiment onboard the Russian segment of the International Space Station

Author

Tret’yakov, V. I., Mitrofanov, I. G., Bobronitskii, Yu. I., Vostrukhin, A. V., Gunko, N. A., Kozyrev, A. S., Krylov, A. V., Litvak, M. L., Lopez-Alegria, M., Lyagushin, V. I., Konovalov, A. A., Korotkov, M. P., Mazurov, P. V., Mokrousov, M. I., Malakhov, A. V., Nuzhdin, I. O., Ponomareva, S. N., Pronin, M. A., Sanin, A. B., Timoshenko, G. N., Tomilina, T. M., Tyurin, M. V., Tsygan, A. I., and Shvetsov, V. N.

Published
2010
Full Text
View/download PDF

88. Lunar Exploration Neutron Detector for the NASA Lunar Reconnaissance Orbiter

Author

Mitrofanov, I. G., Bartels, A., Bobrovnitsky, Y. I., Boynton, W., Chin, G., Enos, H., Evans, L., Floyd, S., Garvin, J., Golovin, D. V., Grebennikov, A. S., Harshman, K., Kazakov, L. L., Keller, J., Konovalov, A. A., Kozyrev, A. S., Krylov, A. R., Litvak, M. L., Malakhov, A. V., McClanahan, T., Milikh, G. M., Mokrousov, M. I., Ponomareva, S., Sagdeev, R. Z., Sanin, A. B., Shevchenko, V. V., Shvetsov, V. N., Starr, R., Timoshenko, G. N., Tomilina, T. M., Tretyakov, V. I., Trombka, J., Troshin, V. S., Uvarov, V. N., Varennikov, A. B., and Vostrukhin, A. A.

Published
2010
Full Text
View/download PDF

95. Solar and Heliospheric Phenomena in October–November 2003: Causes and Effects

Author

Veselovsky, I. S., Panasyuk, M. I., Avdyushin, S. I., Bazilevskaya, G. A., Belov, A. V., Bogachev, S. A., Bogod, V. M., Bogomolov, A. V., Bothmer, V., Boyarchuk, K. A., Vashenyuk, E. V., Vlasov, V. I., Gnezdilov, A. A., Gorgutsa, R. V., Grechnev, V. V., Denisov, Yu. I., Dmitriev, A. V., Dryer, M., Yermolaev, Yu. I., Eroshenko, E. A., Zherebtsov, G. A., Zhitnik, I. A., Zhukov, A. N., Zastenker, G. N., Zelenyi, L. M., Zeldovich, M. A., Ivanov-Kholodnyi, G. S., Ignat'ev, A. P., Ishkov, V. N., Kolomiytsev, O. P., Krasheninnikov, I. A., Kudela, K., Kuzhevsky, B. M., Kuzin, S. V., Kuznetsov, V. D., Kuznetsov, S. N., Kurt, V. G., Lazutin, L. L., Leshchenko, L. N., Litvak, M. L., Logachev, Yu. I., Lawrence, G., Markeev, A. K., Makhmutov, V. S., Mitrofanov, A. V., Mitrofanov, I. G., Morozov, O. V., Myagkova, I. N., Nusinov, A. A., Oparin, S. N., Panasenco, O. A., Pertsov, A. A., Petrukovich, A. A., Podorol'sky, A. N., Romashets, E. P., Svertilov, S. I., Svidsky, P. M., Svirzhevskaya, A. K., Svirzhevsky, N. S., Slemzin, V. A., Smith, Z., Sobel'man, I. I., Sobolev, D. E., Stozhkov, Yu. I., Suvorova, A. V., Sukhodrev, N. K., Tindo, I. P., Tokhchukova, S. Kh., Fomichev, V. V., Chashey, I. V., Chertok, I. M., Shishov, V. I., Yushkov, B. Yu., Yakovchouk, O. S., and Yanke, V. G.

Published
2004
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results