Note on tracking Sun-Earth connection event

ICME Event: 2012/01/21

Observer: Jie Zhang on 2018/11/23

1. ICME
  1.1. Catalog
     # Identified in ICME catalogs: Richardson & Can List
      RC catalog:
      Disturbance start time: 2012/01/21 05:01 UT
      Ejecta      Start time: 2012/01/21 06:00 UT
      Ejecta      End   time: 2012/01/22 08:00 UT
      dv = 30 km/s, v = 320 km/s, vmax= 330 km/s
      MC index:     2
      Dst:        -10 nT
      Suggested source CME: 2012/01/18 12:24 UT
      V_transit:  650 km/s
      
  1.2. Comments
      Overall ICME quality index: 2
      ICME signatures: Bmax: 10.9 nT
                       Bz rotation
      Others ICME signature: no
      Peculiar behavior: extremely high plasma density at the center - 50 cm^-3
                         extremely high temperature at the center 3x10^5 k :

      Disturbance time 350 km/s  -> search window 119 hrs -> 2012/01/16 06 UT

2. CME
   2.1. A. Candidate A
    A.1. LASCO:    
      #CME 2012/01/16 03:12 UT, full halo (from CDAW)
           major CME, fast 1060 km/s and bright
	   Sharp LF and fuzzy core, indicating an axial view

    A.2 .STEREO: 
           Also seen as a major CME in COR2-A and COR2 B
	   Front-side halo CME, consistent witht the flare source region

    A.3. AIA & GOES
	   corresponding flare: C2.1 at 2012/01/16 02:48 UT
	                        flare from AR11401 at N17E46

    A.4 Comment:  
	   Unlikey the source: the eject is in the nother-east quadrant
	                       the ejecta does not cross the equator
			       the ejecta does not cross the polar
           Peculiar behavior: LASCO CME shows the axis of the flux rope is along the light of sight. However, the AIA post-eruption arcade shows an orientation of north-south, indicating a size view of the axis. The two views are not reconciled. 

   2.1, B, Candidate B
     B.1. LASCO  
       #CME 2012/01/18 12:24 UT, partial halo (from CDAW)
           fairly major CME, 267 km/s
	   central PA down toward the south pole
	   Two flanks bairely touch the equatorial lines

     B.2. STEREO
         front-side CME with angular widht about 60 degree, mostly southward

     B.3. AIA & GOES
          #GOES flare C2.4 at 2012/01/18 12:10 UT from AR 1401 at N17E32
	   not corresponding to the CME, even though the timing is okay
	      Occur at the northern hemisphere
	      no dimming, a compact flare
	  # coronal dimming as the disk center ~N00E00
	     seen in AIA 131 and other AIA passband
	     No flare
	     Filament activiated, but eruption feature is weak

     B.3. Comment
         Possibly the source, given the true speed is much higher than the projected speed
	 However, the component mostly soutward, not cross the equatorial ine

  2.1.C. Candidate C
      C.1. LASCO
        #CME 2012/01/19 14:36 UT, full halo CME (from CDAW)
	   a major CME, speed 1120 km/s, and bright


      C.2. STEREO
        # major CME, front-side CME

      C.3. AIA and GOES

      C.4. not likely to be the source
           Too close the time
	   Too fast the CME, inconsistent with the arrival time and SW speed at the arrival time

   2.2. Comment
        Likely solar source is Candidate B: 


3. Other Comments


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