Composite 2

The COMPOSITES SURVEYS IIa and IIb covers the 08-16 UT time range (1pixel/60sec) and zooms are 1 hour long (1pixel/10sec).

IIa

IIb

These two surveys are similars except for the EW and NS brightness distributions versus time (C and D) which is :

  1. greyscale (same as COMPOSITE I) for the COMPOSITE IIa
  2. contour plot for the COMPOSITE IIb

The two spectra (A and B) reported in these two surveys are similars .

They are composed of

  • two spectra (A and B)
  • two displays of brightness distribution projected onto the heliocentric East/West or North/South direction versus time at 150/164MHz (C) and 432MHz (D)
  • a position of CMEs detected by SOHO (E)

Two Spectra

1) from 10 (or 20) MHz to 70 MHz. Linear scale.(A)

This spectrum displays data from DAM. When DAM is unavailable, Artemis is used instead.

InstrumentFminFmaxTime resolutionDates
DAM 20 MHz 70 MHz 1 sec From 1st Jan 2002 to present
Artemis 20 MHz 70 MHz 5 sec From 1st Jan 2002 to present
2) from 100 MHz to 2000 or 600 MHz. Linear scale.(B)

This spectrum displays data from Phoenix 2 because of his frequency range (which goes to 2Ghz).
When Phoenix 2 is unavailable, Artemis is used instead up to 600Mhz.
Please note that Phoenix 2 is no longer operationnal from 16 march 2009. So after this date, Artemis is systematicaly used.

InstrumentFminFmaxTime resolutionDates
Artemis 100 MHz 600 MHz 5 secs From 1st Jan 2002 to present
Phoenix 2 112 MHz 2000 MHz 1 sec From 1st Jan 2002 to 16 march 2009

EW and NS brightness distributions versus time at two frequencies

150 MHz (164 MHz before 01 Dec 2006) (C)
432 MHz (D)
Each frame contains a display of brightness distribution projected onto the heliocentric East/West or North/South direction versus time ; the units of the vertical axis are solar radius.

  • IIa displays in greyscale : each scan is normalised to its maximum. All the bursts are visibles but the intensity variations during the day are not well described.
  • IIb displays in contour plot : the normalisation is made on the maximum intensity in the whole day. Contour levels are chosen in order to describe the quiet sun (at least one level) and intenses bursts. This gives a good estimate of intensity variation with the day.
NRH Projection Resolution Time
SurveyIntegration Time
IIa 8h-16h 120s
IIa zoom 10s
IIb 8h-16h 60s
IIb zoom 10s

Coronal Mass Ejections (CMEs) (E)(same as Composite I survey)

The CMEs are reported in the composites IIa and IIb survey from 08 to 16 UT.

  • Time of appearance in SOHO/LASCO C2 and direction (arrow)
  • Speed V(First order, km/sec), angular width W(deg)
  • Black: detected in C2 and C3
  • Grey: detected in C2 only