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Delve into the mysterious transient universe utilizing LWA, operating at wavelengths longer than 3 meters, uncovering radio afterglows, CGRT J1745-3009, and potential discoveries like extra-solar planets. An impressive project by the Southwest Consortium involving 50 stations spread across NM, the LWA aims to bring about groundbreaking insights by detecting and monitoring transient sources, cosmic evolution, particle acceleration, and ionospheric physics with its extensive reach and power. This innovative venture promises to shed light on uncharted territories below 100 MHz, presenting a realm ripe for remarkable new findings.
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Exploring the Transient Universe with the Long Wavelength Array(LWA:http://lwa.nrl.navy.mil) Greg Taylor (KIPAC / NRAO / UNM) for the Southwest Consortium (UNM, NRL, UT, LANL) Wavelengths longer than 3 meters “Long Wavelengths” (LW) Frequencies below 90 MHz
The 2004 Dec. 27 Giant Flare • was ~5ofrom the sun • It’s distance ≈ 15 kpc • Eiso ~ (2-9)1046 erg • Eiso,spike/Eiso,tail ~ 300 • Expanding radio afterglow Swift (Palmer et al. 2005)
Radio Afterglow has a Steep Spectrum ~ -0.6 at t+7 days down to at least 220 MHz Flux > 1 Jy at early times and low frequencies. Visible out to ~ 1 Mpc From Cameron et al. 2005
Image Evolution VLA 8.5 GHz Taylor et al. 2005, astro-ph/0504363
Growth of the Radio Afterglow VLA 8.5 GHz Velocity to t + 30 days ~ 0.8 c Size at t+7 days 1016 cm Decrease in vexp
VLA Y LWA Overview:Far Larger than the VLA Full LWA: 50 stations spread across NM 1 “LWA Station” = 256 antennas State of New Mexico 400 km 100 m
Another recently discovered type of transient radio source: • CGRT J1745-3009 (Hyman et al. 2005) • A periodic flaring to ~1 Jy at 76 min intervals during several months in 2002 • No obvious IR or X-ray counterpart • Tb ~ 1016 K, most likely a coherent emitter • New type of radio source?
Detecting Extra solar Planets • LWA may detect emission from extra-solar “Jupiters” in outburst. • Jupiter exhibits bursts of ~105 Jy at ~ 40 MHz. . Interaction of Jupiter’s magnetosphere with the Solar Wind LWA Range (deca-meter wave) 107 106 105 104 103 102 10 ~40 MHz Brightness Millimeter waves Centimeter waves 1 10 102 103 104 105 106 Frequency (MHz)
Low Frequency Transient Sources • Radio afterglows (GRBs, SNe, magnetars, …) • Extra-Solar planets • Ultra-High Energy Cosmic-ray showers • Prompt GRB and/or SNe emission • Giant pulses from pulsars • Microquasars • AGN flares • Microlensing events • LIGO events? • Evaporating black holes? • … Falcke et al. 2005
SUMMARY • Opportunity • A pathfinder Long Wavelength (LW) system demonstrates we can finally “see” through the ionosphere at high sensitivity below 100 MHz. • The Long Wavelength Array (LWA) project • A Long Wavelength system more than 10X size and 100X the power of a recently developed LW VLA pathfinder system. • A 400 km, completely electronic radio-telescope to be built in NM by the Southwest Consortium, providing arcsecond resolution below 100 MHz. • Goals: • Detection and Monitoring of Transient Sources, Cosmic Evolution, Particle Acceleration, and Ionospheric Physics The Long Wavelength Array will open the last poorly explored region of the spectrum - the potential for new discoveries will be high!