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H.-S. Yu 1, B.V. Jackson 1, P.P. Hick 1, A. Buffington 1, M. M. Bisi 2, D. Odstrcil 3,4, M. Tokumaru 5 1 CASS, UCSD, USA ; 2 STFC RALab, Harwell Oxford, UK 3 George Mason University & NASA/GSFC, United States 4 STELab, Nagoya, Japan A Global Solar Wind Boundary from Remotely-Sensed IPS Data for Driving ENLIL
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2 Introduction Data Sets - Interplanetary scintillation (IPS) IPS data are mainly from STELab, Japan Analysis - 3D Heliospheric Tomography fitting a kinematic model to the IPS data (a time-dependent heliospheric view from a single observer location) Speeds and densities from the IPS, vector fields from solar surface magnetograms Current Applications: A global solar wind boundary for driving 3D-MHD models (UAH/MS-FLUKSS; NRL/H3D-MHD; ENLIL in real time)
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3 STELab IPS array near Mt. Fuji (Same type of array located at Kiso) STELab IPS array systems (Kiso, Mt. Fuji, and Toyokawa) Interplanetary Scintillation (IPS) data - STELab
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4 New STELab IPS array in Toyokawa (3,432 m 2 array now operates well – year-round operation began in 2011) Interplanetary Scintillation (IPS) data - STELab Berine is here
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5 Interplanetary Scintillation (IPS) data - STELab IPS is caused by the presence of density inhomogeneities in the solar wind that disturb the signal from point-like radio sources. These produce intensity variations that, when projected onto Earth’s surface, make a pattern that travels away from the Sun with the solar wind speed. The correlation of this pattern between different radio sites allows a determination of the solar wind outflow speed. The “normalized scintillation level” (g-level) of an IPS radio source signal relative to a nominal average value allows a determination of the solar wind density.
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6 The Pushchino Radio Observatory 70,000 m 2 110 MHz array, Russia (summer 2006) Now named the “Big Scanning Array of the Lebedev Physical Institute” (BSA LPI). The Ootacamund (Ooty), India off- axis parabolic cylinder 530 m long and 30 m wide (15,900 m 2 ) operating at a nominal frequency of 326.5 MHz. Other Current Operating IPS Radio Systems
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7 MWA (Western Australia) (32 tiles are now operating. The full array 128 tiles can obtain some IPS data.) LOFAR (Western Europe) (Some parts of the system are now operating - Richard Fallows, Mario Bisi are involved. IPS/FR tests are ongoing.) MEXART (Mexico)KSWC (South Korea) Dedicated IPS 700 m 2 327 MHz IPS radio 32 tile array, Jeju Island Dedicated IPS IPS 9,600 m 2 140 MHz IPS radio array near Michoacan, Mexico Other and Potential Future IPS Radio Systems IPS Workshop in Morelia, Mexico October 19-23, 2015
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8 3D Heliospheric Tomography The 3D tomographic reconstruction basically proceeds by least- squares fitting a purely kinematic heliospheric solar wind model to the IPS LOS signal assuming radial outflow and enforcing conservation of mass and mass flux (Jackson et al., 1998). The UCSD 3D-reconstructed heliospheric density, velocity, and vector magnetic fields are available, as standard, from 15 Rs out to 3.0 AU and can be extracted at any distance in between to provide inner boundary inputs to drive 3D-MHD forward modeling.
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9 A Global Solar Wind Boundary for 3D-MHD models – H3D-MHD
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10 3D Heliospheric Tomography- 2011/09/24 CME Sequence A pair of closely-spaced CMEs erupted from NOAA AR1302 in conjunction with an M7 strength solar flare.
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11 3D Heliospheric Tomography- 2011/09/24 CME Sequence
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12 9/26 th Geomagnetic Storm B z became sharply south at times solar wind increase from 350km/s to over 700 km/s
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13 UCSD IPS Analysis (Yu et al., 2015)
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14 UCSD IPS Analysis (1-day average) date UT 0.93 shock CME1 CME2 shock CME1 CME2
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15 (Yu et al., 2015) IPS driven 3D-MHD: H3D-MHD (40 Rs, 5 o x5 o )
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16 IPS driven 3D-MHD: H3D-MHD (1-day average) date UT 0.58 0.73 shock CME1 CME2 shock CME1 CME2
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17 A Global Solar Wind Boundary for 3D-MHD models – ENLIL
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18 (Yu et al., 2015) IPS driven 3D-MHD: ENLIL (0.1 AU, 4 o x4 o )
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19 IPS driven 3D-MHD: ENLIL (1-day average) date UT 0.45 0.90 shock CME1 CME2 shock CME1 CME2
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20 CMEs in HI-1 images
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21 CMEs in HI-1 images
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22 IPS driven 3D-MHD: H3D-MHD & ENLIL (6-hr average) H3D-MHD ENLIL Good fit in magnitude Good fit in timing WIND Model Density Model Velocity
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23 IPS driven ENLIL: Space Weather at Rosetta Spacecraft
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24 2014-09-19 Rosetta plasma energy (IES data) IPS driven ENLIL: Space Weather at Rosetta Spacecraft
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25 IPS driven ENLIL: Space Weather at Rosetta Spacecraft SOHO/LASCO HALO CME Sep.09, 2014 C2 Start Time: 00:06 UT C3 Start Time: 00:31-06:28 UT Type of CME: Asymmetric HALO CME — FRONTSIDE pa1: 064 pa2: 063 Total Width: 360 degrees Velocity Measurements: C2: 5 points 0896.5 km/sec @ PA 064 C3: 12 points 1004.7 km/sec @ PA 064 Average through both fields: 0972.6 km/sec @ PA 064 Acceleration: 18.30 m/sec^2 GOES reports a LDE M4.5 class X-ray flare at 23:12/00:29/01:31 UT from AR 12158
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26 SOHO/LASCO HALO CME Sep.10, 2014 C2 Start Time: 18:00 UT C3 Start Time: 18:06-22:30 UT Type of CME: Asymmetric HALO CME — FRONTSIDE pa1: 335 pa2: 334 Total Width: 360 degrees Velocity Measurements: C2 2 points 1416.5 km/sec @ PA 335 C3 12 points 1193.5 km/sec @ PA 335 Average through both fields: 1209.0 km/sec @ PA 0335 Acceleration: -29.13 m/sec^2 GOES reports a LDE X1.6 class X-ray flare at 17:21/17:45/18:20 UT from AR 12158 IPS driven ENLIL: Space Weather at Rosetta Spacecraft
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27 IPS driven ENLIL: Space Weather at Rosetta Spacecraft
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28 IPS driven ENLIL: Space Weather at Rosetta Spacecraft
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29 IPS driven ENLIL: Space Weather at Rosetta Spacecraft
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30 IPS driven ENLIL: Space Weather at Rosetta Spacecraft
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31 (Yu, H-S., et al., 2015, Solar Phys.; Jackson, B.V., et al.,., 2015, Space Weather) Updated every 6 hours at: ftp://cass185.ucsd.edu/data/IPSBD_Real_Time/ENLIL/ascii_data Real-time IPS-Derived Boundaries for 3D-MHD Model
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32 IPS driven ENLIL in Real-Time ENLIL run daily on a GMU test site by Dusan Odstrcil. See: http://spaceweather.gmu.edu/projects/enlil/models/ipsbd/den1r2e4b/index.htm
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33 IPS driven ENLIL in KSWC ENLIL run with a six hour cadence (planned) on the KSWC Website See: http://www.spaceweather.go.kr/models/ipsdenlil
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34 Summary The analysis of IPS data provides low-resolution global measurements of density and velocity with a time cadence of about one day for both density and velocity, and slightly longer cadences for some magnetic field components. Evaluating the 3D reconstruction at a given spherical radius provides a “global solar wind lower boundary” which can then be extrapolated outward by 3D-MHD models. The 3D-MHD simulation results using IPS boundaries as input compare fairly well with in situ measurements. Real-time IPS boundary data for driving MHD model (ENLIL) are now available.
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