wavelengths by using UTR-2 radio telescope Ukraine: A.Konovalenko , V.Zakharenko , V.Kolyadin , O.Ulyanov, I.Falkovich , V.Melnik , G.Litvinenko, M.Sidorchuk, S.Stepkin, I.Bubnov et al. France: Ph. Zarka, L. Denis, A. Coffre, J.-M. Griessmeir, J.Girard, I.Cognard, M.T agger, A. Lecacheux , C. Rosolen, J.-L.Bougeret et al. Austria: H.Rucker , G.Fisher et al. Germany: G. Mann, K. Breitling et al . Sweden: B. Thide, R.Karlsson Transients KSP LOFAR Meeting Meudon, 14 December, 2011 (For now it is in the frame of PICS Project CNRS – NSAU “Development of the low frequency radio astronomy with ultrahigh sensitivity and resolution”)
MHz) in the stellar and planetary science Solar system + 1. The Sun (sporadic radio emission) + 2. The Sun (quiet) + 3. Solar wind (IPS, scattering) + 4. Earth ionosphere ⇓ ~ 5. Space weather + 6. Jupiter (DAM) + 7. Planetary lightnings (Saturn, etc.) - 8. The Moon (cosmic rays) Galaxy - 9. Exoplanets (hot jupiters) + 10. Active stars ⇓ - 11. “Galactic” weather + 12. Other stars (i.e. C II regions near B - stars → RRL’s) + 13. Pulsars - 14. Transients
astronomy (from the astrophysical point of view as well as in the frame of ionospheric and interference effects mitigation) • Frequency range ~ 10 – 100 MHz • Instant band > 20 MHz • Max ;me resolu;on 1µs …1ms • Frequency resolu;on ~ 1 kHz • Dynamic range > 90 dB (16-‐bit ADC) (front-‐end, back-‐end) • Sensi;vity up to 1 mJy (with corresponding resolu;on, band, everaging) • Eﬀec;ve area 104 …106 sq. m • Angular resolu;on ~10 ang.min…~ 1ang.sec. (large eﬀec;ve area is more important when the sensi;vity is not limited by the confusion eﬀect) • Large ﬁeld of view, mul;-‐beam capabili;es (ON-‐OFF), all sky coveraging or full hemisphere steering • So[ware antenna structure (digital imaging) or op;mal combina;on of analog and digital phase systems • Distant antennas implementa;ons (100…1000 km) in VLBI and / or synchronized modes
FPGA technology) 7 sets are on the Ukrainian radio telescopes (UTR-‐2, URAN-‐2, URAN-‐3, GURT): • 2 sets were developed in the frame of ANR Project, France (Ph.Zarka); • 5 sets were developed in the frame of NASU Special Program, Ukraine (A. Konovalenko) Instant frequency band 32 MHz Number of eq.channals 8192 Frequency resolu;on 4 kHz Max ;me resolu;on 0,5 ms Dynamic range 90 dB(16-‐bit ADC) Input channels 2 Auto-‐ and cross-‐spectra yes Wave-‐form yes R.Kozhin, V.Vinogradov ,D.Vavriv. Low-noise, high dynamic range digital receiver/ spectrometer for radio astronomy applications. MSMW 07 Symp. Proceedings, Kharkov, Ukraine, June 29-30, 2007, p. 736-738. V.Ryabov, D. Vavriv, Ph.Zarka, B.Ryabov, R.Kozhin, V.Vinogradov, L.Denis. A low-noise, high-dynamic-range, digital receiver for radio astronomy applications: an efficient solution for observing radio-bursts from Jupiter, the Sun, pulsars, and other astrophysical plasmas below 30 MHz. Astronomy and Astrophysics, 2010, v.510.
astronomy There is Special Programme of NaAonal Academy of Sciences of Ukraine(2006…2009 and future): 1. Upgrade of world largest exis3ng Ukrainian decameter wave-‐ length radio telescope UTR-‐2, URAN-‐1 … URAN-‐4 ( f= 8…32 MHz; Aeﬀ max = 200 000 sq. m, Nel ~ 4 000) 2. Crea3on of new genera3on Ukrainian low frequency radio telescope GURT – Giant Ukrainian Radio Telescope (f= 10…70 MHz; Aeﬀ max > 100 000 sq. m, Nel ≥ 1 000, step -‐by – step) ( output data format should be compa3ble to LOFAR)
goal is high sensi3ve, broad-‐band, high 3me and frequency resolu3on, high interference immune studies of the Universe at extremely low frequencies when the sensi3vity is non –l imited prac3cally by the confusion eﬀect ( ∆S min.ﬂ. ≤ ∆S min.conf. ): frequency range (up to ionosphere limit) 10 – 70 MHz instant frequency band 60 MHz eﬀec3ve area ( step -‐ by – step ) 104 → 106 sq.m exceeding of antenna temperature ≥ 10 dB exceeding of dynamic range ≥ 20 dB two polariza3on, mul3-‐beam capabili3es ﬂexibility
and stellar LF radio astronomy. The implementation of largest existing radio telescopes, new generation high performance back-ends and methods gave many interesting astrophysical results. The creation and using of new generation low frequency radio telescopes (LOFAR, LWA, E-LOFAR, LSS, GURT, etc.) have good perspectives. It is valied also for the experiments with the distant antennas (up to ~ 1000 km ) in VLBI and/or synchronized modes