J/ApJ/896/133 2001-2019 ICME associated Forbush decrease events (Light+, 2020)
Interplanetary coronal mass ejection associated Forbush decreases in neutron
monitors.
Light C., Bindi V., Consolandi C., Corti C., Freeman C., Kuhlman A.,
Palermo M., Wang S.
<Astrophys. J., 896, 133 (2020)>
=2020ApJ...896..133L 2020ApJ...896..133L
ADC_Keywords: Sun
Keywords: Galactic cosmic rays ; Heliosphere ; Solar activity ;
Solar coronal mass ejections ; Solar-terrestrial interactions
Abstract:
Interplanetary coronal mass ejections (ICMEs) are eruptions of plasma
that propagate outward through the heliosphere. ICMEs, and the shocks
they drive, cause a sudden decrease in the cosmic-ray flux in their
local area of the heliosphere, called a Forbush decrease (FD). A
method of defining FDs is established, and an automated process for
identifying FDs in neutron monitor (NM) data is created. The
correlation between ICME properties and FD magnitude in 12 different
NMs is examined for 91 ICME-associated FD events occurring from 2001
through 2019 August. A number of ICME properties show positive
correlation with FD magnitude, with decreasing correlation strength as
NM cutoff rigidity increases.
Description:
This work studies correlations between solar wind measurements and
Forbush decrease (FD) magnitude, using neutron monitor (NM) data from
12 NMs between 2001 January and 2019 August.
The 12 neutron monitors used in this study:
--------------------------------------------------------
Neutron Monitor Cutoff FD events
name rigidity (GV) identified
--------------------------------------------------------
Inuvik (INK) 0.30 333
Nain (NAN) 0.30 318
Thule (THL) 0.30 386
Apatity (ATY) 0.65 335
Oulu (OLU) 0.81 329
Kerguelen (KGN) 1.14 337
Moscow (MCW) 2.43 267
Jungfraujoch (IGY; JGY) 4.49 343
Jungfraujoch (NM64; J64) 4.49 392
Hermanus (HMN) 4.58 348
AlmaAtaB (AAB) 6.69 318
Athens (ATH) 8.53 314
--------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 144 319 Forbush decrease (FD) events marked in at least
4 neutron monitors
table3.dat 175 91 Dip size for Interplanetary coronal mass ejection
(ICME) associated FD events
--------------------------------------------------------------------------------
See also:
J/A+A/422/337 : Solar EUV Post-Eruptive Arcades (Tripathi+, 2004)
J/A+A/440/373 : Earthbound interplanetary shocks (Howard+, 2005)
J/ApJ/709/1238 : Solar Coronal Mass Ejection (Yeates+, 2010)
J/ApJ/737/L35 : Pulsed Alfven waves in the solar wind (Gosling+, 2011)
J/ApJ/759/69 : Solar electron events 1995-2005 with WIND/3DP (Wang+, 2012)
J/MNRAS/456/1542 : Predicting CMEs transit times (Sudar+, 2016)
J/ApJ/831/105 : Global energetics of solar flares. IV. CME (Aschwanden, 2016)
J/ApJS/230/21 : Solar wind 3D magnetohydrodynamic simulation (Chhiber+, 2017)
J/ApJS/239/12 : Small-scale magnetic flux ropes in the solar wind (Hu+, 2018)
J/ApJ/868/124 : ICMEs events from 1998 to 2011 with ACE and WIND (Feng+, 2018)
J/ApJ/871/93 : Solar wind speed from 5yr data with ACE (Wang+, 2019)
J/ApJ/891/54 : Solar X-ray flares & associated CME widths (Ling+, 2020)
J/ApJ/891/79 : Single storms and the related ICMEs from 1998-2011 (Li+, 2020)
J/A+A/635/A79 : Pitch-angle distributions of solar wind (Carcaboso+, 2020)
http://www.nmdb.eu/nest/ : NMDB Event Search Tool home page
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 yr Obs.Y Year of the Forbush Decrease (1)
6- 7 I2 "month" Obs.M Month of the Forbush Decrease (1)
9- 10 I2 d Obs.D Day of the Forbush Decrease (1)
12- 21 F10.8 --- INK [0/0.235] Dip size from Inuvik neutron monitor (2)
23- 32 F10.8 --- NAN [0/0.231] Dip size from Nain neutron monitor (2)
34- 43 F10.8 --- THL [0/0.232] Dip size from Thule neutron monitor (2)
45- 54 F10.8 --- ATY [0/0.227] Dip size from Apatity neutron monitor (2)
56- 65 F10.8 --- OLU [0/0.234] Dip size from Oulu neutron monitor (2)
67- 75 F9.7 --- KGN [0/0.234] Dip size from Kerguelen
neutron monitor (2)
77- 86 F10.8 --- MCW [0/0.223] Dip size from Moscow neutron monitor (2)
88- 96 F9.7 --- JGY [0/0.221] Dip size from JungfraujochIGY
neutron monitor (2)
98-107 F10.8 --- J64 [0/0.224] Dip size from JungfraujochNM64
neutron monitor (2)
109-118 F10.8 --- HMN [0/0.184] Dip size from Hermanus
neutron monitor (2)
120-129 F10.8 --- AAB [0/0.214] Dip size from AlmaAtaB
neutron monitor (2)
131-141 F11.9 --- ATH [0/0.168] Dip size from Athens neutron monitor (2)
143-144 I2 --- Nev [4/12] Number of neutron monitors event found in
--------------------------------------------------------------------------------
Note (1): The date is included for event identification.
Note (2): The Dip Size is calculated using the 24 hour period before the
FD time for the maximum, and the 36 hour period after the FD time
for the minimum. A zero indicates that the FD was not identified
in that neutron monitor.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 yr Obs.Y Year of the Forbush Decrease (1)
6- 7 I2 "month" Obs.M Month of the Forbush Decrease (1)
9- 10 I2 d Obs.D Day of the Forbush Decrease (1)
12- 21 F10.8 --- INK [0/0.126] Dip size from Inuvik neutron monitor (2)
23- 31 F9.7 --- NAN [0/0.129] Dip size from Nain neutron monitor (2)
33- 41 F9.7 --- THL [0/0.126] Dip size from Thule neutron monitor (2)
43- 52 F10.8 --- ATY [0/0.120] Dip size from Apatity neutron monitor (2)
54- 63 F10.8 --- OLU [0/0.127] Dip size from Oulu neutron monitor (2)
65- 73 F9.7 --- KGN [0/0.123] Dip size from Kerguelen
neutron monitor (2)
75- 84 F10.8 --- MCW [0/0.118] Dip size from Moscow neutron monitor (2)
86- 94 F9.7 --- JGY [0/0.135] Dip size from JungfraujochIGY
neutron monitor (2)
96-105 F10.8 --- J64 [0/0.134] Dip size from JungfraujochNM64
neutron monitor (2)
107-116 F10.8 --- HMN [0/0.103] Dip size from Hermanus
neutron monitor (2)
118-127 F10.8 --- AAB [0/0.098] Dip size from AlmaAtaB
neutron monitor (2)
129-139 F11.9 --- ATH [0/0.084] Dip size from Athens neutron monitor (2)
141-142 I2 --- Nev [5/12] Number of neutron monitors event found in
144-153 I10 --- Shock [0/1557788400] Shock arrival time (3)
155-164 I10 --- Start [0/1557820800] ICME cloud start time (3)
166-175 I10 --- End [0/1557968400] ICME cloud end time (3)
--------------------------------------------------------------------------------
Note (1): The date is included for event identification.
Note (2): The dip size is calculated using the time period before the shock
(or before the magnetic cloud, if no shock is visible) to calculate
the maximum; and the time period during the magnetic cloud (or after
the shock, if no magnetic cloud is visible) to calculate the minimum.
A zero indicates that the FD was not identified in that neutron
monitor.
Note (3): In unix time format, i.e. number of ms elapsed since January 1, 1970
00:00:00 (UTC).
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 02-Nov-2021