J/ApJ/710/1111 Observations of interplanetary shocks (Gopalswamy+, 2010)
Interplanetary shocks lacking type II radio bursts.
Gopalswamy N., Xie H., Makela P., Akiyama S., Yashiro S., Kaiser M.L.,
Howard R.A., Bougeret J.-L.
<Astrophys. J., 710, 1111-1126 (2010)>
=2010ApJ...710.1111G 2010ApJ...710.1111G
ADC_Keywords: Sun
Keywords: shock waves - solar wind - Sun: coronal mass ejections (CMEs) -
Sun: flares - Sun: particle emission - Sun: radio radiation
Abstract:
We report on the radio-emission characteristics of 222 interplanetary
(IP) shocks detected by spacecraft at Sun-Earth L1 during solar cycle
23 (1996 to 2006, inclusive). A surprisingly large fraction of the IP
shocks (∼34%) was radio quiet (RQ; i.e., the shocks lacked type II
radio bursts). We examined the properties of coronal mass ejections
(CMEs) and soft X-ray flares associated with such RQ shocks and
compared them with those of the radio-loud (RL) shocks. The CMEs
associated with the RQ shocks were generally slow (average speed
∼535km/s) and only ∼40% of the CMEs were halos. The corresponding
numbers for CMEs associated with RL shocks were 1237km/s and 72%,
respectively. Thus, the CME kinetic energy seems to be the deciding
factor in the radio-emission properties of shocks.
Description:
The starting point of this paper is the set of interplanetary (IP)
shocks detected near Earth by one or more of the following spacecraft:
the Solar and Heliospheric Observatory (SOHO), the Advanced
Composition Explorer (ACE), and Wind. Table 1 contains information on
the shocks, the associated ejecta (EJ), the solar source (coronal mass
ejection (CME), flare), and type II radio emission (metric and IP).
For shocks and EJ, the starting time and speed at 1AU are given along
with the shock observing spacecraft (A = ACE, W = Wind, S = SOHO).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 142 230 List of IP shocks observed during solar cycle 23
and their source information
notes.dat 75 67 Notes
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See also:
J/ApJ/709/1238 : Comparison of global model with CMEs (Yeates+, 2010)
J/A+AS/119/489 : Solar Type II Radio Bursts, 1990.09 - 1993.12 (Mann+ 1996)
J/A+A/304/563 : Cool X-ray flares of Sun with GOES (Phillips+, 1995)
J/A+AS/110/99 : White-light flares models (Fang+, 1995)
http://wind.nasa.gov/mfi/ : WIND spacecraft Magnetic Field Investigation
(MFI) home page
http://www.cfa.harvard.edu/shocks/ : CfA interplanetary shock database
http://cdaw.gsfc.nasa.gov/CME_list/ : SOHO LASCO CME catalog online
http://cdaw.gsfc.nasa.gov/CME_list/radio/waves_type2.html : Wind/WAVES type
II burst catalog online
ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SOLAR_RADIO/SPECTRAL/
TypeII/TypeII_1994-2009 : type II burst data available on line at the
National Geophysical Data Center (NGDC)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 "YYYY/MM/DD" IP.date Interplanetary shock arrival date
12- 16 A5 "h:m" IP.time Interplanetary shock arrival time
18- 22 A5 --- Inst [WAS, ] shock observing spacecrafts
(Wind, ACE or SOHO)
24- 30 F7.2 km/s IP-Vel Interplanetary shock speed
32- 36 F5.2 --- Ma Interplanetary shock Alfvenic Mach number
(MA; Eq. 1 and section 3.1)
38 I1 --- r_Ma Source of Mach number computation (2)
40- 41 A2 --- CMEt Coronal Mass Ejection (CME) type (3)
43- 46 F4.1 h Tstd ? IP CME shock standoff distance
expressed as arrival time difference
48 A1 --- f_CMEtime [*] Flag indicating CMEtime was the next day
49- 53 A5 "h:m" CMEtime IP CME arrival time
55- 58 I4 km/s CME-Vel ? IP CME shock speed
60- 69 A10 "YYYY/MM/DD" CME.date Coronal Mass Ejection white-light date
71- 75 A5 "h:m" CME.time Coronal Mass Ejection white-light time
77- 79 I3 deg PA ? Coronal Mass Ejection white-light
central position angle
80 A1 --- f_PA [H/D]? H: Halo ; D: DG (4)
82 A1 --- l_CME-W Limit flag on CME-W
83- 85 I3 deg CME-W ? Coronal Mass Ejection white-light width
87- 90 I4 km/s CME-V ? Coronal Mass Ejection white-light speed
92- 97 F6.1 m/s2 CME-a ? Coronal Mass Ejection white-light
acceleration
99-104 A6 --- SF-Loc Solar Flare location
106-114 A9 --- SF-Dur Solar Flare duration (hhmm-hhmm)
116-120 A5 --- SF-Size Solar Flare size in soft X-rays (5)
122 I1 --- MC [0/1]? Type II Burst metric type II code
(1: metric emission or 0: no metric)
124-128 A5 "h:m" IIBtime Type II Burst metric onset time
130 I1 --- DH [0,3]? Type II Burst
decameter-hectometric type II code (6)
132-136 A5 "h:m" DHtime Type II Burst decameter-hectometric onset
time
138-142 A5 --- Note Comment number(s) (see notes.dat file)
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Note (2): The Mach numbers were obtained from one of the following three
methods:
1 = J. C. Kasper compilation of shocks: http://www.cfa.harvard.edu/shocks;
2 = Vinas & Scudder, 1986JGR....91...39V 1986JGR....91...39V, analysis method based on the
Rankine-Hugoniot conservation equations;
3 = Approximation - see section 3.1 (Eq 1).
Note (3): Interplanetary CME type as follows:
S = Sheath only;
EJ = Ejecta;
MC = magnetic cloud.
Note (4): DG indicates CME data gap. CME-W=360 degrees if Halo.
Note (5): Abbreviations as follows:
EP = eruptive prominence;
DIM = dimming;
Wave = EIT wave.
Note (6): code as follows:
0 = no radio emission;
1 = radio emission in RAD2 (1-14MHz);
2 = radio emission in RAD1 (30kHz-1MHz);
3 = radio emission in RAD1+RAD2.
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Byte-by-byte Description of file: notes.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Note Code of note
4- 75 A72 --- Text Text of note
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 15-Mar-2012