![Page 1: Wave Injection at Low Latitudes Mark Golkowski Remediation of Enhanced Radiation Belts Workshop Lake Arrowhead, CA March 3-6, 2007](https://reader035.vdocuments.mx/reader035/viewer/2022070412/56649d605503460f94a40b9c/html5/thumbnails/1.jpg)
Wave Injection at Low Latitudes
Mark Golkowski
Remediation of Enhanced Radiation Belts Workshop
Lake Arrowhead, CA
March 3-6, 2007
![Page 2: Wave Injection at Low Latitudes Mark Golkowski Remediation of Enhanced Radiation Belts Workshop Lake Arrowhead, CA March 3-6, 2007](https://reader035.vdocuments.mx/reader035/viewer/2022070412/56649d605503460f94a40b9c/html5/thumbnails/2.jpg)
2
Adelaide, Australia
~500 kW ? Navigation transmitter in Komsomolsk na Amur in Russian far east (400 msec pulses) at L = 2
Conjugate point in southern Australia
Stanford University receiver since January 2007
Explore and quantify wave-growth
Stanford Scientists Kangaroos
![Page 3: Wave Injection at Low Latitudes Mark Golkowski Remediation of Enhanced Radiation Belts Workshop Lake Arrowhead, CA March 3-6, 2007](https://reader035.vdocuments.mx/reader035/viewer/2022070412/56649d605503460f94a40b9c/html5/thumbnails/3.jpg)
3
Russian Alpha Transmitters
3.6 second pattern (six 0.6s segments) 400ms pulses, 200ms off between pulses Three sites alternate among 3 frequencies
14.88 kHz
![Page 4: Wave Injection at Low Latitudes Mark Golkowski Remediation of Enhanced Radiation Belts Workshop Lake Arrowhead, CA March 3-6, 2007](https://reader035.vdocuments.mx/reader035/viewer/2022070412/56649d605503460f94a40b9c/html5/thumbnails/4.jpg)
4
Historical Background
Triggered emissions have been observed from other mid-latitude transmitters: NAA (L=2) 14.5 kHz, 200 msec pulses
Whistler-mode Komsomolsk Alpha pulses have been studied by Tanaka et al. 1987 in the context of whistler propagation characteristics
![Page 5: Wave Injection at Low Latitudes Mark Golkowski Remediation of Enhanced Radiation Belts Workshop Lake Arrowhead, CA March 3-6, 2007](https://reader035.vdocuments.mx/reader035/viewer/2022070412/56649d605503460f94a40b9c/html5/thumbnails/5.jpg)
5
Example 1-Hop
2
2
1A
Becc
![Page 6: Wave Injection at Low Latitudes Mark Golkowski Remediation of Enhanced Radiation Belts Workshop Lake Arrowhead, CA March 3-6, 2007](https://reader035.vdocuments.mx/reader035/viewer/2022070412/56649d605503460f94a40b9c/html5/thumbnails/6.jpg)
6
Temporal (non-linear) Growth
![Page 7: Wave Injection at Low Latitudes Mark Golkowski Remediation of Enhanced Radiation Belts Workshop Lake Arrowhead, CA March 3-6, 2007](https://reader035.vdocuments.mx/reader035/viewer/2022070412/56649d605503460f94a40b9c/html5/thumbnails/7.jpg)
7
Example Growth
~7-8 dB total
~70-80 dB/sec
![Page 8: Wave Injection at Low Latitudes Mark Golkowski Remediation of Enhanced Radiation Belts Workshop Lake Arrowhead, CA March 3-6, 2007](https://reader035.vdocuments.mx/reader035/viewer/2022070412/56649d605503460f94a40b9c/html5/thumbnails/8.jpg)
8
Example Growth
![Page 9: Wave Injection at Low Latitudes Mark Golkowski Remediation of Enhanced Radiation Belts Workshop Lake Arrowhead, CA March 3-6, 2007](https://reader035.vdocuments.mx/reader035/viewer/2022070412/56649d605503460f94a40b9c/html5/thumbnails/9.jpg)
9
Example Detection
![Page 10: Wave Injection at Low Latitudes Mark Golkowski Remediation of Enhanced Radiation Belts Workshop Lake Arrowhead, CA March 3-6, 2007](https://reader035.vdocuments.mx/reader035/viewer/2022070412/56649d605503460f94a40b9c/html5/thumbnails/10.jpg)
10
10-Day Statistics (1-10 April)
Count of 1-hop observations in synoptic (1min/5min) recordings
10 days during and after a geomagnetic disturbance
1-Hop observations show qualitative relationship to geomagnetic activity
Need more data to quantify relationship
![Page 11: Wave Injection at Low Latitudes Mark Golkowski Remediation of Enhanced Radiation Belts Workshop Lake Arrowhead, CA March 3-6, 2007](https://reader035.vdocuments.mx/reader035/viewer/2022070412/56649d605503460f94a40b9c/html5/thumbnails/11.jpg)
11
Diurnal patterns
Day DayNight Day DayNight
![Page 12: Wave Injection at Low Latitudes Mark Golkowski Remediation of Enhanced Radiation Belts Workshop Lake Arrowhead, CA March 3-6, 2007](https://reader035.vdocuments.mx/reader035/viewer/2022070412/56649d605503460f94a40b9c/html5/thumbnails/12.jpg)
12
Average Daily Variations
Sunrise
Sunset
Tanaka et al. 1987 Stanford 2008
Diurnal variation shows maxima after sunset and sunrise
Tanaka et al. 1987: diurnal variation is same for whistlers and is a propagation effect (duct formation, coupling in/out of duct)
![Page 13: Wave Injection at Low Latitudes Mark Golkowski Remediation of Enhanced Radiation Belts Workshop Lake Arrowhead, CA March 3-6, 2007](https://reader035.vdocuments.mx/reader035/viewer/2022070412/56649d605503460f94a40b9c/html5/thumbnails/13.jpg)
13
Summary
1-Hop echoes regularly observed from Komsomolsk Alpha transmitter
Echoes exhibit temporal growth of ~70-80 dB/sec Propagation delays of 460 msec – 540msec
equatorial electron concentrations of 4000-5000 cm-3 at L = 2
Triggered of frequency emmisions not observed yet, except perhaps on DEMETER satellite
Diurnal variations likely result from propagation/ducting effects
Future Work: statistically quantify effect of geomagnetic conditions on wave growth