- Количество слайдов: 56
t l e Yu. D. Kotov and CORONAS-PHOTON team Scientific objectives and observational capabilities of "Coronas-Photon" project Federal Space Agency Russian Academy of Science Principal Organization: Moscow Engineering Physics Institute (Technical University)
Russian program CORONAS КОРОНАС Комплексные ОРбитальные Околоземные Наблюдения Активности Солнца CORONAS Complex ORbital Observatio. N of Activity of Sun CORONAS-I с 03. 1994 по 12. 2000 CORONAS-F с 07. 2001 по 12. 2005 (IZMIRAN, CB“Yuznoe”) ----||---- CORONAS-PHOTON 2008 (Astrophysics Institute of MEPh. I, NIIEM, VNIIEM)
CORONAS-PHOTON mission is the third satellite of the Russian CORONAS program on the Solar activity observations. The main goal of the CORONASPHOTON mission is the study of the Solar flare hard electromagnetic radiation in the wide energy range from Extreme UV up to high energy gamma - radiation (~2000 Me. V)
Magnetic structure as it is seen in UV Magnetic field dominates plasma creates intricate structure/ heats TRACE
Generation of gamma-rays in the solar atmosphere be accelerated particles
Electromagnetic radiation spectrum from intense solar flare
Cycle 24 Maximum • The panel is split down the middle on whether it will be bigger than average or smaller than average, namely: • Will peak at a sunspot number of 140(± 20) in October, 2011 Or • Will peak at a sunspot number of 90(± 10) in August, 2012 – An average solar cycle peaks at 114 – The next cycle will be neither extreme, nor average
CONSENSUS STATEMENT OF THE SOLAR CYCLE 24 PREDICTION PANEL March 20, 2007 • The Solar Cycle 24 Prediction Panel anticipates the solar minimum marking the onset of Cycle 24 will occur in March, 2008 (± 6 months). The panel reached this conclusion due to the absence of expected signatures of minimum-like conditions on the Sun at the time of the panel meeting in March, 2007: there have been no high-latitude sunspots observed with the expected Cycle 24 polarity; the configuration of the large scale whitelight corona has not yet relaxed to a simple dipole; the heliospheric current sheet has not yet flattened; and activity measures, such as cosmic ray flux, radio flux, and sunspot number, have not yet reached typical solar minimum values. • In light of the expected long interval until the onset of Cycle 24, the Prediction Panel has been unable to resolve a sufficient number of questions to reach a single, consensus prediction for the amplitude of the cycle. The deliberations of the panel supported two possible peak amplitudes for the smoothed International Sunspot Number (Ri): Ri = 140 ± 20 and Ri = 90 ± 10. Important questions to be resolved in the year following solar minimum will lead to a consensus decision by the panel. • The panel agrees solar maximum will occur near October, 2011 for the large cycle (Ri=140) case and August, 2012 for the small cycle (Ri=90) prediction.
New model Mausumi Dikpati and colleagues (Geophys. Research Letters, March 3, 2007) A National Solar Observatory map of observed magnetic fields correlates closely with the NCAR model of the fields. Both images show the longitudinal averages of the fields. (Courtesy Mausumi Dikpati, Giuliana de Toma, Peter Gilman, Oran White, and Charles Arge). Scientists for years have known about the current of plasma, or the meridional flow, which moves at about 20 meters (66 feet) per second near the surface. But they had not previously connected it to sunspot activity.
Latitude distribution of the flares
As the plasma current approaches the poles, it sinks about 200, 000 kilometers down into the Sun’s interior and starts its return journey back to the equator The Great Conveyor Belt is a massive circulating current of fire (hot plasma) within the Sun. It has two branches, north and south, each taking about 40 years to perform one complete circuit. Researchers believe the turning of the belt controls the sunspot cycle, and that's why the slowdown is important. "Normally, the conveyor belt moves about 1 meter per second-walking pace, " says Hathaway. "That's how it has been since the late 19 th century. " In recent years, however, the belt has decelerated to 0. 75 m/sec in the north and 0. 35 m/sec in the south. "We've never seen speeds so low. " According to theory and observation, the speed of the belt foretells the intensity of sunspot activity about 20 years in the future. A slow belt means lower solar activity; a fast belt means stronger activity. "The slowdown we see now means that Solar Cycle 25, peaking around the year 2022, could be one of the weakest in centuries, " says Hathaway
Предсказания: Активность на 50% больше, чем в 23 цикле. Начало цикла в конце 2007 или начале 2008. Максимум в 2012 BUT! Phys. Rev. Lett. 98 131101 Arnab Rai Choudhuri and colleagues from the Indian Institute of Science in Bangalore and the Chinese Academy of Sciences in Beijing calculate that the next cycle (known as cycle 24) will be about 35% weaker than cycle 23 (11 April 2007)
W. Dean Persell, April 2007
Orbit and Launcher Satellite CORONAS – PHOTON (METEOR type) Weight <2250 kg Launcher: Cyclon-3 M Cosmodrome: Plesetsk Orbit: Circular 550± 10 km. Inclination 82. 5 deg Nominal mission lifetime extended 3 years 5 years Telemetry 8. 2 GHz; Onboard memory 1. 0 Gbyte Launching date at the summer season of the 2008
CORONAS-PHOTON Spacecraft Orientation of longitudinal axis to the Sun direction (day part of orbit) Destabilization of the longitudinal axis during the shadow part of the orbit * Signals from instrument TESIS will be used to get: transverse axes stabilization longitudinal axis stabilization Accuracy of time registration Pointing accuracy 10' (nominal)* 0. 3'/sec ≤ 0. 5 deg ≤ 3′ 1 msec Posteriori pointing accuracy 1. 5' Angular disturbance is less than 0. 005 deg/s
Scientific payload Instruments for charge particle measurements Instruments for registration of gammaradiation and neutrons Seven Full Solar disk UV & soft X-ray monitors Simi-imaging RT-2 X-ray monitor + Magnetometer TESIS assembly of instruments for XUV imaging spectroscopy of the Sun
Российские участники проекта «КОРОНАС-ФОТОН» (создание научной аппаратуры) ШМосковский инженерно-физический институт (МИФИ), Москва - головной ШНаучно-исследовательский институт ядерной физики МГУ (НИИЯФ МГУ), Москва ШФизико-технический институт РАН (ФТИ РАН), Санкт-Петербург Ш Физический институт РАН (ФИ РАН), Москва ШИнститут земного магнетизма, ионосферы и распространения радиоволн РАН (ИЗМИРАН), Троицк ШИнститут космических исследований РАН (ИКИ РАН), Москва
Зарубежные участники проекта «КОРОНАС-ФОТОН» (создание научной аппаратуры) Ш Харьковский национальный университет (ХНУ), Харьков, Украина Ш Taтa институт фундаментальных исследований (ТИФР), Мумбай, Индия Ш Сцинтилляционные детекторы США Ш Полупроводниковые детекторы CZT Израиль Ш Многоканальная электроника Норвегия Ш Центр космических исследований Польской академии наук (ЦКИ ПАН), Вроцлав, Польша Ш Полупроводниковый детектор США
Full Solar disk UV & soft X-ray monitors Instrument Radiation bands Temporal resolution Detector type Sphin. X Space Res. Center, Poland PI J. Sylwester P. N. Lebedev PI, Russia MEPh. I, Russia Soft X-rays 0. 5 ke. V– 15 ke. V Solar disk radiation monitoring up to 10 msec Pure Si PIN-diode 500μm thick, aperture 19. 96, 0. 397 and 0. 0785 mm 2 (Amptek, USA) PHOKA Russia MEPh. I, PI A. Kochemasov 4 channels (nm) Visible, FUV & XUV <1100; 116125; 27 -37 & <11 Solar disk radiation monitoring 2 sec Occultation mode 0. 1 sec AXUV-100 G 10 mmx 10 mm (International Radiation Detectors, CA, USA) SOKOL Russia, IZMIRAN, PI V. D. Kuznetsov 7 Visible & NUV channels (nm) 1500, 1100, 850, 650, 500, 350, 280 (bandwidth <10%) Solar disk radiation monitoring 30 sec Photodiodes with filter (effect. square
TESIS assembly of instruments for XUV imaging spectroscopy of the Sun It is advanced version of the SPIRIT instrument Kuzin S. et al; Cospar meeting 2006 talk E 2. 1 009 - 06
Instruments for charge particle measurements 3 -axis magnetometer Magnetometer SM-8 M three components of FGU NPP “Geologorazvedka”, magnetic field in the range St-Petersburg, Russia; of – 55 T … +55 T MEPh. I, Russia PI V. N. Yurov
TESIS STEP-F KONUS-RF-anti pressure vessel PHOKA RT-2/GA RT-2/S KONUS-RF N-2 M RT-2/G PINGUIN Magnetometer
Ground segment CORONAS-PHOTON project
Energy channels of Natalya-2 M instrument (defined by trigger mode) Channel Energy region, Me. V Effective area, cm 2 Energy resolution ΔE /E Timing X-ray and gamma-rays R 0, 3 – 2 920 10% (662 ke. V) measured L 2 – 10 900 5% (2, 5 Me. V) measured 1 ms 1 sec M 7 – 200 800 6% (10 Me. V) calculated 1 sec H 50 – 2000 750 32% (500 Me. V) calculated 1 sec Neutrons N (neutrons) 20 – 300 37 – 120 – 32 sec
Data readout from the high-energy radiation spectrometer NATALYA-2 M
Data readout from spectrometer KONUS-RF Two detectors based on Na. I(Tl) scintillator Ø 127 x 76. 2 mm
Gamma-line response NATALYA-2 M L-mode 1. 0 -10. 0 Me. V
neutron/gamma pulse shape discrimination 3 D diagram of energy output verses pulse shape parameter in Cs. I(Tl) detector 14 Me. V neutron beam calibration
Pinguin-M (disassembled) Anticoincidence counter Na. I(Tl) detector of scattering X-rays PTF counter to scatter X-rays Proportional counters Anticoincidence counter
Three RT-2 detectors Two phoswich detectors One CZT detector n. The Tantalum Coded Mask is coded by open and close pattern of squares of size 2. 5 mm. Its dimensions are 180 x 0. 5 mm. Four CDZ modules Mechanical slat collimator made up of Tantalum surrounded by a graded shield with viewing angles of 4º x 4º and 6º x 6º respectively.
Coded Mask Imaging Concept Multiple pin-hole MASK Mask casts shadow on detector plane Shift of shadow pattern encodes source location Cross correlation of mask pattern with shadow recovers shift and locates sources
Design characteristics of RT-2. Type Thickness (mm) Phoswich Na. I(Tl)+Cs. I(Na) 3+25 CZT 5 40 X 40 (4 numbers) Size (mm) 117. 6 dia Readout PMT 1024 pixels (ASIC) Effective area (cm 2) (@60 ke. V) 100 64 Energy resolution (@60 ke. V) 18% 8% 15 – 150 ke. V (extended 2 Me. V) 10 – 100 ke. V 10 10 Energy range Time Resolution (ms)
Specifications of CZT detector Area Pixels 64 cm 2 1024 Pixel size 2. 5 mm X 2. 5 mm (5 mm thick) Read-out ASIC based (8 chips of 128 channels) Imaging method Coded Aperture Mask (CAM)/ FZP Field of View 6 o X 6 o CAM 3 o X 1. 5 o. FZP Angular resolution 30 arcmin/ 30 arcsec Energy resolution 5% @ 100 ke. V (< 8%) Energy range 10 – 100 ke. V Up to 1 Me. V (Photometric)
CZT: Hard X-ray detector of the future …. . Good energy resolution Good efficiency Pixelated : Moderate imaging Background estimation Avoids source confusion Background reduction Good spectroscopic detector Note: Used up to now only as a gamma-ray imager
Fresnel’s Zone Plate • It is made up of Tantalum of 1 mm thickness and alternate solid and hollow regions with 4 flanges to support the overall structure. It is fabricated using MEMS. • The deconvolution of source is done from the interference fringes formed by two zone plates. The radii of the annulus are governed by: rn = (n)1/2 x r 1 where, r 1 = radius of innermost disc It has following advantages over contemporary decoding methods: (i) Very high order of precision of source location. (ii) Highly economical in terms of volume.
FXM YАl. O 3(Ce) YAP(Ce): Yttrium Aluminum Perovskite doped with Cerium (chemical formula YAl. O 3: Ce) is a non-hygroscopic, glasslike, inorganic scintillator with a high density, but a relatively low effective atomic number (36). The wavelength of maximum emission is 35 nm, the decay time is short, 27 ns, the light output is typically 40% of that of Na. I(Tl) and the material is relatively stable over a wide temperature range. dimensions of 13 mm in height and 68 mm in diameter In intense flare temporal resolution up to 1 ms
Multi-channel solar photometer SOKOL Continuous observations of the solar radiation intensity variations in range 280 - 1500 nm, relative intensity resolution 2 х10 -6 of total solar intensity, observation angle - 2°. Technical parameters: • radiation intensity is measured simultaneously in 7 optical spectrum bands by 8 photosensors: 280, 350, 500, 650, 850, 1100 and 1500 nanometers with the measuring bandwidth below 10% of the value of central wavelength. • relative intensity resolution is 2 х10 -6 of the total solar radiation intensity. • temporal resolution of intensity measurements - 30 sec. • spacial resolution is not available. • photometer observation angle - 2°. • precision of the photometer orientation towards the center of the solar disk is 5 arc. min. • the photometer consists of the photosensors unit PU and electronics unit EU. Dimensions: PU - 130 х510 mm. Weight: 5. 2 kg. View of instrument
STEP-F instrument is able to register fluxes of: electrons 0. 4 – 14. 3 Me. V; protons of 9. 8 – 61. 0 Me. V; alpha-particles of 37. 0 – 246. 0 Me. V. The detector block includes two identical silicon position-sensitive detectors and two scintillation detectors. Each silicon detector has the size of 45× 45 mm and 350 μm thickness. Scintillation detectors are based on Cs. I(Tl) crystals and viewed by large area photodiodes. The average telescope field of view is 97× 97°. The size of each of 36 matrix square elements of semiconductor detector is 7. 3× 7. 3 mm, which allows to receive the average angular resolution in telescope total field of view about 8°. The effective area of each semiconductor detector is 20 сm 2, scintillation detectors is 36 and 49 сm 2. Geometric factor of STEP-F instrument is 20 сm 2·str.
STEP-F D 1: Si, h = 0. 03 cm 45× 45 mm D 2: Si, h = 0. 03 cm 45× 45 mm D 3: Cs. I(Tl), h = 1. 3 cm 60× 60 mm D 4: Cs. I(Tl), h = 1. 0 cm 70× 70 mm D 1, D 2 – silicon position-sensitive totally depleted pin-detectors; D 3, D 4 – scintillation detectors.