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National Research Nuclear Univercsty MEPhI (NRNU MEPhI) Moscow, Russia. Radiation Laboratory. Measuring complex for detection of radioactive waste in the near-Earth space. ¹S.E. Ulin, ¹ K.F. Vlasik, ¹ V.M.Grachev, ¹V.V. Dmitrenko, ¹ A.S. Novikov,
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National Research Nuclear Univercsty MEPhI (NRNU MEPhI) Moscow, Russia Radiation Laboratory Measuring complex for detection of radioactive waste in the near-Earth space ¹S.E. Ulin, ¹ K.F. Vlasik, ¹ V.M.Grachev, ¹V.V. Dmitrenko, ¹ A.S. Novikov, ¹ Z.M. Uteshev, ¹A.E. Shustov, ¹D.V.,I.V.Chernishova, ² N.S.Bakhtigaraev, ²L.V.Rykhlova , 3 S.G.Kazatsev 1 - Moscow Engineering Physics Institute, seulin@gmail.com, 2 - Institute of Astronomy of RAS (INASAN), nail@inasan.ru 3 - JSC "NIIEM",sg.kazantsev@niiem.ru Moscow 2016
INTRODUCTION • Space objects, that represent a potential threat of radioactive contamination of near-Earth space, should remain on the "burial" orbits for hundreds of years. • However, this is true only if their physical characteristics are stability. • The probability of collisions of the spacecraft with nuclear units on board with space debris elements on the "burial" orbits dramatically increased.
Waste in near-Earth space Density of waste, km3 Height, km The distribution of space waste at altitudes from 100 to 2000 km 3
Radioisotope power sources The energy of the natural radioactive decay is used in radioisotope sources. 3 4 1 2 5 Schematic diagram of the radioisotope power source. 1 – radiation shield, 2- radioactive nuclide, 3 – cooling circuit, 4 – thermoelectric converter, 5 - electric battery. 4
Radioisotope power sources Radioisotope Generator SNAP-19 (USA) Power: 25 W It was designed for the satellite "Transit-5." Usedin it radioisotope plutonium Pu-238 provided reliable operation in space during 6 years. SNAP-19 was installed on a space probe "Pioneer" and worked on it for more than 5 years. Radioisotope Generator SNAP-19, "Pioneer" probe. 5
Radioisotope power sources It is interesting also isotopes of heavy transuranic elements, especially plutonium Pu-238, curium Cm-242, Cm-244, Cm-245, californium Cf-248, Cf-249, Cf-250, Einstein Es-254, fermium Fm-257 and a number of lighter isotopes. 7
Radioactive waste of the isotope energy sources • Short-lived isotopes 242Cmand its decay products. • Among the radioactive isotope waste, the long-lived isotopes of • α - emitters 232U, 238Pu, 241Am, 244Sm produce the greatest risk. • The isotope energy sources and isotope heaters used on spacecraft, • currently mainly long-lived isotope 238238Pu is used. It together • with fission products have high toxicity and danger for human health. • 4. The long-lived isotopes 60Co and 137Cs provide risk because the • β - decay is always accompanied by the emission of high energy • gamma-rays.
The radioactive fissile materials in the near-Earth space Nuclear reactor SNAP-10A (OPS 4682) was launched in the United States on April 3, 1965. Its inclination and height orbit are 90.17 degrees and 1283 x 1312 km. The reactor was successfully operated 43 days before the May 16, 1965 Thehorizon sensor was destroyed as a result of numerous high-breakdown.Details of the reflector have been destroyed under the influence of false commands from the voltage regulator. Many different debris - fragments was formed.
Cosmos 1818 Launched February 2, 1987 from the Baikonur Cosmodrome, rocket "Cyclone-2”. Satellite length - 10 m, diameter - 1.3 m, weight - 3800 kg, including a reactor - 980 kg. Perigee - 790 km Apogee - 810 km The period of revolution around the Earth - 100.6 minutes The angle of inclination of the orbital plane to the plane of Earth's equator - 65 °.
Spent fuel of nuclear reactors Nuclear power units on the spacecraft is used mainly nuclear reactors to thermal neutrons with a weakly or strongly enriched 235U as fuel, as well as nuclear reactors on fast neutrons, running on a mixture of uranium and plutonium, and using potassium-sodium melt as a heat carrier. The main types of nuclear fuel used in nuclear reactors, are the following: - natural uranium (99,274% 238U, 0,721% 235U, 0,006% 234U); - weakly enriched uranium (~3% 235U); - highly enriched uranium (more 90% 235U); -a mixture of uranium and plutonium;. 11
Spent fuel of nuclear reactors In a nuclear reactor after a combustion of fuel, consisting of 3.3% 235U and 96,7% 238 U, in the end of years of its operation in fuel remains: 0,8% 235U и 94,4% 238U. 0,5% 236U, 0,5% 239Pu, 0,2% 240Pu, 0,1% 241Pu 3.5% of the fission products of which 0,3% 137Cs, 0,09% 129I, 0,03% 90Sr. The dependence of the amount of the resulting radionuclide(moles per ton of fuel) from the time operation of the nuclear reactor (in days). The dotted line shows the radionuclide concentration, multiplied by 10. 12
Spent fuel of nuclear reactors The largest contribution to the activity of the spent fuel from the three-year holding time is made: 137Cs+137mBa (24%), 144Ce+144Pr (21%), 90Sr+90Y (18%), 106Ru+106Rh (16%), 147Pm (10%), 134Cs (7%), The relative contribution of 85Kr, 154Eu, 155Euequal approximately 1% of each isotope. In the first few decades: 137Cs+137mBa, 90Sr+90Y, 241Pu, n the next century: 99Tc, 237Np, 239Pu, 240Pu и 241Am Among the α - radioactive isotopes of spent nuclear fuelе the first most dangerous provide: short-lived isotope 242Cm, 134Cs и 147Pm, after one year isotopes 241Am, 238Pu и 244Cm,90Sr, 241Pu и 237U, after ten thousand years 237Np и 243Am, 239Np и 242Am,99Tc и 129I. n a million years 237Np, 236U и 238U. Among the gamma - radioactive isotopes of spent nuclear fuelе the first most dangerous provide: the first of short-lived isotopes 106Ru и 144Ce, following decades isotope137Cs. 14
The components of the radioactive waste in near-Earth space Radioactive space debris may consist of various components, whose characteristics, can be divided into three groups: 1. Fragments of nuclear power reactors; 2. Muted reactors; 3. Operational satellites with nuclear reactors, which may be faced with space debris or meteoroids. Radioactive elements of these three groups have specific characteristics of neutron and gamma- radiation.
Methods of radioactive elements monitoring in near-Earth space Various methods are used for detecting and identifying of radioactive waste.They can be divided into several groups. 1. Gamma-ray spectrometric methods. Gamma spectrometer with high sensitivity and high energy resolution allows measuring the energy spectrum emitted by objects and determine their isotopic composition and mass. 2. Neutron methods. Neutron techniques allow to measure the neutron flux. 3. Registration of infrared radiation. The images in the infrared range of the satellite can determine its temperature. 4. Optical methods. Registration of objects that are associated with radioactive waste can be provide determination of their trajectory.
Sputnik "Coronas-F” The orbit of the satellite "Coronas-F“: height 500.9 x 548.5 km; Inclination 82.49 °; circulation period of 94,859 minutes. It provides recurring periods of continuous observations of the sun for about 20 days duration, which is especially important for patrol solar phenomena and flares, registering global solar oscillations.
Gamma-ray detector SONG-D Detector SONG-D Scintillator The photomultiplier Electronic bloc Sizes of crystal CsI (Tl) Ø200x100 mm3. Mass 11 кг. Energy resolution 10-12 %
Radioactive space debris 1100 1000 900 800 700 Counts, 1/s Counts, 1/s Time 18.10.2001 21:01:24.197 UT, s Time 18.10.2001 21:01:24.197 UT, s а б Passage of satellite OPS DEB 4682 at a distance about ~186 km from the CORONAS-F in the area of the equator. (а) the part of the orbit CORONAS-F, (б) the same event without background. 19
Observatory (INASAN) Terskolskaya Observatory The telescope Zeiss-2000 (D=2 m, F=16 m), equipped with a CCD camera FLI PL 4301 (2084 x 2084 cells , sight 12ch12 arcminutes. Observed objects have22th magnitude (less than 10 cm) in geostationary orbit. 20
Spacecraft with nuclear installations NumberName InclinationHeight apogee Heightperigee (degree) (km) (km) 01574 COSMOS 84 56.06 1568 1471 01588 COSMOS 90 56.06 1661 1399 04564 COSMOS 367 65.28 1020 920 11788 COSMOS 1176 64.83 964 873 11971 COSMOS 1176 FUEL CORE 64.84 940 870 27568 COSMOS 1176 COOLANT 64.82 919 839 29019 COSMOS 1176 COOLANT 64.84 921 873 17369 COSMOS 1818 65.01 800 775 34174 COSMOS 1818 DEB 65.01 800 774 34175 COSMOS 1818 DEB 65.01 800 775 34176 COSMOS 1818 DEB 65.01 799 776 34177 COSMOS 1818 DEB 65.01 801 775 35518 COSMOS 1818 DEB 65.01 799 775 36132 COSMOS 1818 DEB 65.01 800 775 18187 COSMOS 1867 65.01 801 777 18957 COSMOS 1932 65.04 987 944 19162 COSMOS 1932 FUEL CORE 65.04 958 943 28275 COSMOS 1932 COOLANT 65.04 982 940
SC Convergence In the period from July 2001 to December 2002 Coronas-F spacecraft was closer to three of the 75 potential radiation hazardous objects. Average elements of their orbits have been identified on September 2001.
Schematic diagram of xenon gamma spectrometer «Nuclide" 1 2 3 4 5 6 7 8 9 1. The cylindrical pulsed ionization chamber 2. The mesh 3. Hermetic package 4. Anode 5. Ceramic faith through 6. Charge sensitive amplifier 7. High-voltage power supply 8. Electronics 9. Scintillation anticoincidence screen 23
Basic physical and technical characteristics of HPT XeGD 1.Mass, kg 5.0 2.The mass of the working substance, kg 2.0 3. Working volume, сm3 4000 4. Dimensions, mm (diameter) 120 (length) 500 5. Wall thickness, mm 0.5 6. Temperature range, °С 0 ÷ 100 7. The level of acoustic loads, dB 0 ÷ 100 24
Comparison of the measured spectra of gamma-ray source of 241 Am by detectors with different walls of the ionization chamber 25
"Canopus-B-IR" under the conditions of orbital flight НFlight direction Nuclide Prototypes of equipment "nuclide" created and studied in MEPhI. Total weight can be from 10 to 100 kg. Installation is possible on the "Meteor-M", "Meteor-MP" and "Resource-MP".
"Canopus-B-IR" under the conditions of orbital flight Field of viewNuklide Nuklide Nuklide Direction of flite
The results of calculations for selected objects Cosmos series satellites, for that is known about the presence on board of radioactive isotopes, were chosen for calculations Calculations show that if equipment “Nuclide“ will be install on board "Meteor", itsclosing in with known potentially dangerous radioactive objects will be about 1-2 times per month.
Investigation of radioactive cosmic waste Sun light Study object 30
The aims of the experiment “Nuclide" • Testing methods of detection and identification of radioactive objects of cosmic waste together withground-based observations in the optical range. • Registration of gamma-rays from the upper layers of the atmosphere (environmental monitoring). 3. Investigation of solar gamma-ray bursts and predicting space weather. • Investigation of gamma-ray bursts from the space objects. 5.The study of charged particle fluxes in the Earth's radiation belts and their influence on the radiation environment in near-Earth space