HMI Ring Diagrams
Data Product Descriptions

hmi.rdMAI_fd05

Data Series Class: Local Helioseismology Activity Indices
Creating Module: maicalc
Input Data: hmi.M_45s

Data Processing Status

The series began to be populated as part of the Ring-Diagrams pipeline beginning with CR 2195 (Sep 2017). It was retrospectively populated working backward in time from CR 2195. Records for CR 2096–2194 were fully populated as of 20 April 2018.

Note that in the filling of records for times not populated as part of the Ring-Diagrams pipeline, the minimum data coverage criterion of 70% is not applied. Only intervals for which no suitable magnetograms exist are skipped. There are only a few such intervals to date for this series: 2136:270, 2162:300, 2172:330, 2180:320–305, 2180:290–285. 2209:180–175, and 2209:135

Values of the keyword CRLN_OBS describing the Carrington longitude of the central meridian at the time of observation in the input magnetograms hmi.M_45s (and the other corresponding observables, as well as those in the 720-sec cadence series) were erroneous, consistently too high by 0°.081894, corresponding to a time offset of 1 AU/c and a plate location offset of about 3 pixels. The correction for new data is pending as of 13 Jan 2023. This may introduce a detectable error in the tracking rate. Processing of uncorrected data corrects for this error beginning with maicalc v 2.3.

Versions of creating module used to produce records in the data series:

v 2.0 : CR 2126:360 – 2199:005 (except 2195:070 and 2196:335)
v 2.1 : CR 2195:070, 2196:335, 2200:360 – 2228:100
v 2.2 : CR 2228:095 – 2234:005
v 2.3 : CR 2096:250 – 2099:005, 2235:360 – 2240:155
v 2.4 : CR 2100:360 – 2125:005, 2240:150 – 2249:030
v 2.5 : CR 2250:360 –

Note that records created with Version 2.0 originally lacked valid values for several keywords: Samples, MeanMu, MeanPA, and COMMENT. However, values for the first three of these have been subsequently set by an independent module using the same algorithm, data, and parameters.

Also, because the MAI is a linear fit at the target time of the several means of |B_z| at the sample times, it can potentially be negative, especially if all available values are on one side of the target time. This “feature” was addressed in Version 2.1, replacing a negative extrapolated or interpolated value at the target time with a simple mean. There are 1679 records in this series with negative values of MAI. The distribution by contributing sample count is:

2: 637 (of 8244)
3: 236 (of 8202)
4: 158 (of 10,971)
5: 584 (of 30,144)
6: 20
7: 38
8: 6 (four in 2163:105 — 135.0+70.0, 150.0+70.0, 175.0+40.0, and 177.5+40.0; the two others are 2172:015 065.0-80.0; 2186:160 232.5+25.0)
9–12: 0

The following records were subsequently reprocessed and for some time existed in multiple versions in the DRMS database:

[2213][150][][-55.0 - -90.0] : 289 records, originally processed 2019.02.14, reprocessed same day
[2218][360][][27.5 - 20.0] : 250 records, originally processed 2019.06.16, reprocessed 2019.06.17
[2218][355][][-40.0 - -52.5] : 204 records, originally processed 2019.06.16, reprocessed 2019.06.17
[2235][225][][-40.0 - -52.5] : 182 records, originally processed 2020.09.30, reprocessed same day
[2261][020][][52.5 - -90.0] : 2459 records, originally processed 2022.09.25, reprocessed same day

After verification that the reprocessed records were identical in all key values other than the Created date, the reprocessed records were removed on 2023.01.13,

All data records originally produced with versions 2.0–2.2 of maicalc have been mirrored to the data series hmi.rdMAI_fd05_reproc, with the exception of the 8202 subsequently reprocessed records in [2197][340-330] that had been originally processed 2017.11.19–20 (reprocessed 2017.12.18).

For current processing status, see the Ring-Diagram Status page.

Data Notes

The constant keywords in the JSOC Series Definition assure that the reference space-time data cubes are colocated with and mapped at the same scale as those for data based on those in hmi.rdVtrack_fd05, although mapped with a Lambert Azimuthal Equivalent projection rather than Postel's (they are nearly identical at this size), and apodized in space and time the same way as the power spectra in hmi.rdVpspec_fd05. Also, the “noise” cutoff value must be 50 gauss.

In producing these data, one in 64 of the input magnetograms are sampled, for a nominal cadence of once every 48 minutes. Alternate nearby magnetograms (out to a distance of 24 min) may be used if those at the nominal target times are missing or unacceptable. The list of magnetograms used is in the key HISTORY.

The fixed arguments to maicalc used in populating this series are:

los= hmi.M_45s
mai= hmi.rdMAI_fd05
scale= 0.04
extent= 5.12
length= 768
rec_step= 64
qmask= 0x8001c540
reject= ~jsoc/hmi/tables/LHS_reject.M45
max_reach= 0.5
floor= 50
mask_in= 0.9765625
apodize= 0.96875

During the time range CR 2115-2200 (Sep 2011 – Feb 2018) the ten tracked regions with the largest MAI, all clearly associated with the disc passage of NOAA AR 12192, were:

2156:205 240.0–15.0 — 821.62
2156:240 242.5–15.0 — 817.80
2156:225 242.5–15.0 — 816.20
2156:255 242.5–15.0 — 814.84
2156:210 240.0–15.0 — 813.28
2156:230 242.5–15.0 — 809.10
2156:200 240.0–15.0 — 805.81
2156:245 242.5–15.0 — 804.52
2156:220 242.5–15.0 — 795.28
2156:215 240.0–15.0 — 794.02

The ten time samples with the largest values of MAI averaged over all regions were:

2156:250 (2014.10.23_08:04) — 8.775
2156:225 (2014.10.25_05:34) — 8.758
2156:245 (2014.10.23_17:10) — 8.744
2156:220 (2014.10.25_14:40) — 8.714
2156:230 (2014.10.24_20:28) — 8.700
2156:255 (2014.10.22_22:58) — 8.694
2156:235 (2014.10.24_11:22) — 8.694
2156:240 (2014.10.24_02:16) — 8.602
2156:215 (2014.10.25_23:45) — 8.534
2156:260 (2014.10.22_13:52) — 8.432

JSOC Series Definition

#=====Global Series Information=====
Seriesname:	hmi.rdMAI_fd05
Description:	"Magnetic Activity Index series for 5-deg tiles"
Author:		"Rick Bogart"
PrimeKeys:	CarrRot, CMLon, LonHG, LatHG, LonCM
DBIndex:	CarrRot, CMLon, LonHG, LatHG, LonCM
Version:	2.1

#=====Links=====

# ===== Keyword list ===== #
# Format:
#   Keyword: <name>, link, <linkname>, <target keyword name>, <comment>
# or
#   Keyword: <name>, <datatype>, {constant | variable}, {record | segment}, 
#            <default value>, <format>, <unit>, <comment>
       
Keyword: CarrRot, int,    variable, record, -1,  %d,     N/A, "Carrington rotation at MidTime"
Keyword: CMLon,   float,  slot,     record, 360, %03.0f, deg, "Longitude of central meridian at MidTime"
Keyword: LonHG,	  float,  slot,     record, NaN, %05.1f, deg, "Longitude of tracked region center"
Keyword: LatHG,	  float,  slot,     record, NaN, %+05.1f, deg, "Latitude of tracked region center"
Keyword: LonCM,   float,  slot,     record, NaN, %+05.1f,  deg, "CM (Stonyhurst) Longitude of region center at MidTime"
Keyword: MAI,     float,  variable, record, NaN, %.3f, G, "Magnetic Activity Index"
Keyword: dMAIdt,  float,  variable, record, NaN, %.3f, uG/s, "Rate of change of Magnetic Activity Index"
Keyword: MeanBigBz,float, variable, record, NaN, %.3f, G, "Signed mean of strong field"
Keyword: dMnBigBdt,float, variable, record, NaN, %.3f, uG/s, "Rate of change of signed strong field mean"
Keyword: BigBArea, float, variable, record, NaN, %.4f, N/A, "Fraction of area covered by contributing field"
Keyword: T_OBS,   time,   variable, record, JD_0, 0, TAI, "Effective sample-weighted observation time"
Keyword: BMin,    float,  variable, record, NaN, %.0f, G, "Minimum contributing B  value"
Keyword: LonBMin, float,  variable, record, NaN, %06.2f, deg, "Longitude of minimum contributing B  value"
Keyword: LatBMin, float,  variable, record, NaN, %+06.2f, deg, "Latitude of minimum contributing B  value"
Keyword: t_BMin,  time,   variable, record, JD_0, -1, TAI, "Time of minimum contributing B  value"
Keyword: BMax,    float,  variable, record, NaN, %.0f, G, "Maximum contributing B  value"
Keyword: LonBMax, float,  variable, record, NaN, %06.2f, deg, "Longitude of maximum contributing B  value"
Keyword: LatBMax, float,  variable, record, NaN, %+06.2f, deg, "Latitude of maximum contributing B  value"
Keyword: t_BMax,  time,   variable, record, JD_0, -1, TAI, "Time of maximum contributing B  value"
Keyword: RMax,	  float,  variable, record, NaN, %06.4f, N/A, "Maximum magram r/R location in apodization circle"
Keyword: MeanMu,  float,  variable, record, NaN, %.4f, N/A, "Mean center-to-limb parameter"
Keyword: MeanPA,  float,  variable, record, NaN, %.1f, deg, "Mean position angle on image"
Keyword: BadPix,  float,  variable, record, NaN, %.6f, N/A, "Maggram pixel fraction in apodization circle offlimb or despiked"
Keyword: Samples, short,  variable, record, -1, %d, N/A, "Number of contributing time samples"
Keyword: Module,  string, variable, record, unknown, %s, N/A, "Creation module"
Keyword: Source,  string, variable, record, unknown, %s, N/A, "Input data source"
Keyword: Created, time,   variable, record, JD_0, -1, Z, "Record creation time"
Keyword: BLD_VERS,string, variable, record, unknown, %s, N/A, "JSOC library build"
Keyword: HISTORY, string, variable, record, "", %s, N/A, "Record creation/modification history"
Keyword: COMMENT, string, variable, record, "", %s, N/A, ""
# remainder are constant for series
Keyword: MapProj, string, constant, record, LambertAzimuthal, %s, N/A, "Map projection"
Keyword: MapScale,float,  constant, record, 0.040, %.3f, deg/pixel, "Map scale"
Keyword: BFloor,  float,  constant, record, 50.0, %.2f, G, "Cutoff for rejection of weak field"
Keyword: Size,    float,  constant, record, 5.12, %.2f, deg, "Diameter of region (nominal)"
Keyword: Apode_t, float,  constant, record, 0.96875, %.5f, NA, "Temporal apodization edge"
Keyword: Apod_Min,float,  constant, record, 0.9765625, %.7f, NA, "Inner spatial apodization edge"
Keyword: Apod_Max,float,  constant, record, 1.000, %.4f, NA, "Outer spatial apodization edge"
# prime key slotting info (hidden)
Keyword: CMLon_base, float, constant, record, 360, %.0f, deg, "CMLon index base"
Keyword: CMLon_step, float, constant, record, -5, %.0f, deg, "CMLon index step"
Keyword: LonHG_base, float, constant, record, 0.0, %.1f, deg, "LonHG index base"
Keyword: LonHG_step, float, constant, record, 2.5, %.1f, deg, "LonHG index step"
Keyword: LatHG_base, float, constant, record, 90.0, %.1f, deg, "LatHG index base"
Keyword: LatHG_step, float, constant, record, -2.5, %.1f, deg, "LatHG index step"
Keyword: LonCM_base, float, constant, record, 0.0, %.1f, deg, "LonCM index base"
Keyword: LonCM_step, float, constant, record, 2.5, %.1f, deg, "LonCM index step"

#=====Segments=====
#
# none
#

HMI Ring Diagrams

13 Jan 2023, 12:36-0800