VI/151 Search for radio emission from giant exoplanets (Griessmeier, 2016)
The search for radio emission from giant exoplanets.
Griessmeier J.-M.
<8th International Workshop on Planetary, Solar and Heliospheric Radio
Emissions, Seggauberg near Leibnits/Graz, Astria, October 25-27, 2016>
=2017yCat.6151....0G 2017yCat.6151....0G
ADC_Keywords: Stars, double and multiple ; Planets ; Radio sources
Description:
The intensity of Jupiter's auroral radio emission quickly gave rise to
the question whether a comparable coherent emission from the
magnetosphere of an exoplanet could be detectable. An exoplanetary
radio emission would have to be at least 1000 times more intense than
Jupiter's emission to be detectable with current radio telescopes.
Theoretical models suggest that, at least in certain cases, the radio
emission of giant exoplanets may indeed reach the required intensity.
At the same time, in order to generate such an emission, an exoplanet
would have to have a sufficiently strong intrinsic planetary magnetic
field. Extrasolar planets are indeed expected to have a planetary
magnetic field, but to date, their magnetic field has never been
detected. We will show that the most promising technique to observe
exoplanetary magnetic fields is indeed to search for the planetary
auroral radio emission. The detection of such an emission would thus
constitute the first unambiguous detection of an exoplanetary magnetic
field. We will review recent theoretical studies and discuss their
results for the two main parameters, namely the maximum emission
frequency and the intensity of the radio emission. The predicted
values should allow the detection using modern low-frequency radio
telescopes. We will present an ongoing observation program with the
Low Frequency Array (LOFAR), which has the potential to detect
exoplanetary radio emission.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 77 1076 Expected exoplanetary radio emission frequencies
and flux densities
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See also:
J/ApJ/612/511 : Exoplanet radio emission (Lazio+, 2004)
J/A+A/562/A108 : 150MHz emission from exoplanets (Sirothia+, 2014)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 23 A23 --- Planet Planet name
25- 32 F8.3 AU rmin Periastron distance
35- 39 F5.1 MHz fc1 Expected maximum emission frequency (case 1) (1)
42- 47 F6.1 mJy Phi1 Expected maximum radio flux density at Earth
(case 1) (1)
51- 55 F5.1 MHz fc2 ?=- Expected maximum emission frequency
(case 2) (1)
58- 60 F3.1 mJy Phi2 ?=- Expected maximum radio flux density at Earth
(case 2) (1)
65- 69 F5.1 MHz fc3 ?=- Expected maximum emission frequency
(case 3) (1)
72- 77 F6.1 mJy Phi3 ?=- Expected radio flux density (case 3) (1)
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Note (1): Cases as follows:
case 1 = assuming rotation has no influence on the planetary magnetic field
case 2 = assuming rotation has a strong influence on the planetary magnetic
field, but the planet is not tidally locked
case 3 = assuming rotation has a strong influence on the planetary magnetic
field, and the planet is tidally locked
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History:
* 13-Sep-2017: Original version
Acknowledgements:
Jean-Mathias Griessmeier, jean-mathias.griessmeier(at)cnrs-orleans.fr
(End) Patricia Vannier [CDS] 13-Sep-2017