Concept of the LORD experiment

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Concept of the LORD experiment

• V.Chechin
• for the LORD Collaboration

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Layout of LORD
LORD Lunar Orbital Radio Detector
Moon
CR, neutrino
Multibeam inflatable parabolic antenna (D525
m)
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RF inflatable antennas
10 m
5 m
Biconical feed antennas
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satellite
Moon
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Trigger system

thresholds
Square Law Detectors
Dscr
BPF
1th Beam
Dscr
BPF
LNA

Dscr
BPF
Dscr
BPF
2th Beam
Trigger
Trigger Logic of 2th Beam
LNA
OR
3th Beam
LNA
Trigger Logic of 3th Beam
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Basic parameters
Number of beams M 3 Satellite altitude
h ? 500?1000 km Antennas diameter D ?
10?20 m System temperature T ? 300 K Beamwidth
?? ? 0.10.1 Frequency range
f ? 300?700 MHz 4 channels with ?f ?
40?50 MHz Time gate ? ? 20
ns Signal-to-noise ratio SNR ? 3?5
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Calculation scheme
Antenna f Emin(SNR, kT, Seff, ?f) Geometry h,
RM
Radiation field parameterization RE(W,f,cos?)
Transmission through rough interface
Directional pattern ??
Apertures (km2 ster) ACR, A? (W, Emin, f, h)
Fluxes JCR, J?
Differential event rates JCRACR, J?A?
(1/eV/s) Integral event rates ?JCRACRdW,
?J?A?dW (1/s)
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Angular apertures (ster)
Total apertures (km2 ster)
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Radiation field parametrization

• The basic problem of finding the apertures is the
  calculation of the radiation field with allowance
  for its absorption and refraction on the rough
  interface as well as near-field effects. Instead
  of performing Monte Carlo simulations we used the
  known parametrization

f0?2500 MHz. The function ?(f,W) for hadronic
showers was found by fitting Monte Carlo
results for ice in the form ? ?AB log(W) and
scaling from ice to lunar regolith
For neutrino-produced showers, W?ltygtW?
Transmission coefficient with allowance for wave
divergence and lunar surface roughness (Dq from
2 to 5 degree)
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Differential aperture dA/d(nadir)
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CR and NU apertures SNR4
Over whole visible surface
LORD
cosmic rays
LORD10
neutrinos
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COSMIC RAYS
h1000 km
h1000 km
Diameter of parabolic antennas
d10 m
Satellite altitude
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COSMIC RAYS
h1000 km d10 m
h1000 km d10 m
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Neutrino
h1000 km
h1000 km
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LORD10
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LORD and LORD10 limits on ? flux 1
year LORD azimuth2p Eth0.01?V/m MHz LORD10
Eth0.07?V/m MHz azimuth0.3
LORD10
Models TD topological defects MPR Mannheim,
Proteroe, Rachen WB Waxman, Bahcal GZK ? min
Np?Ep2, max Np?Ep1
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Torus parabolic multibeam antenna
Frequency 3.7-4.2 GHz Gain
46 dBi Reflector
size 7 m x 12.8m Beamwidth
1 x 2 degrees
Arc Coverage 75
degrees Number of feeds 37
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CR and NU apertures SNR3
Over whole visible area
cosmic rays
LORD
neutrinos
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CR and NU apertures SNR5
Over whole visible surface
cosmic rays
LORD
neutrinos