Note on tracking Sun-Earth connection event

ICME Event: 2011/02/04

Observer: Eleni Nikou on 2019/05

1. ICME
  1.1. Catalog
     # Identified in ICME catalogs: Richardson & Can List
      RC catalog:
      Disturbance start time: 2011/02/04 13:00 UT
      Ejecta      Start time: 2011/02/04 13:00 UT
      Ejecta      End   time: 2011/02/04 20:00 UT
      dv = 20 km/s, v = 430 km/s, vmax= 470 km/s
      MC index:     2
      Dst:        -63 nT
      Suggested source CME: none
      V_transit:  none
      
  1.2. Comments
      Overall ICME quality index: 3
      ICME signatures: Bmax: 21.9 nT
                       Bz rotation - smooth decrease until 2011/02/04 17:00 UT when it reaches a constant plateau for a couple of hours, then it decreases for half an hour and then remains constant until the end of the ejecta
      Others ICME signature: in parts Tp < Texp 
      Behavior: the disturbance and the ejecta have the same start time

      Disturbance time 430 km/s  -> search window 4 days -> 2011/01/30 

2. CME
   2.1. A. Candidate A
    A.1. LASCO:    
      #CME 2011/01/30 12:36 UT, very poor event - C2 (from CDAW)   



    A.2 .STEREO: 
           Also seen as a minor CME in COR2-A and COR2 B, First frame at COR2A: around 6:00 UT - slow event


    A.3. AIA & GOES
	   corresponding flare: poor events with minor brightenings

       GOES: minor flaring activity in different times. The first peak is at 02:41 UT which should most probably correspond to the CME observed by STEREO
       AR11150 B1.3

    A.4 Comment:  
	   1. Possible source region: the eject is in the southern hemisphere, which is consistent with the STEREO and LASCO observations

       2. There is one more partial halo CME, again poor event, at 18:
	                       
  
        B. Candidate B
    B.1. LASCO:    
      #CME 2011/01/30 12:36 UT, very poor event - C2 (from CDAW)   



    B.2 .STEREO: 
           Also seen as a minor CME in COR2-A and COR2 B, First frame at COR2A: around 6:00 UT - slow event


    B.3. AIA & GOES
	   corresponding flare: poor events with minor brightenings (AR11150)

       GOES: minor flaring activity in different times. The first peak is at 02:41 UT which should most probably correspond to the CME observed by STEREO

    B.4 Comment:  
	   Likely the source: the eject is in the nothern hemisphere, which is consistent with the LASCO observations
	                       
   2.2. Comment
        Likely solar source is Candidate A 


3. Other Comments
      
        1: CDAW gives a partial halo CME on 2011/01/18 04:00 UT but it not earth directed, not supported by STEREO - backsided event

        2: CDAW gives a partial halo CME on 2011/01/21 13:25 UT but it moves towards the north, not the equatorial plane.  

4. Summary
    SW index 2
    Source index 3
    Overall index 3.