HMI MDI Comparison

Y. Liu

CR 2104

CR 2109

MDI = 1.2 * HMI 720s / 45s

Mean Field

HMI Magnetic Field Noise Pattern

• Gaussian with of 10000 magnetograms

MDI Magnetic Field Noise Pattern

• MDI has pronounced spatial noise pattern

HMI & MDI Doppler/Magnetic Leakage

Synoptic HMI/MDI Noise Comparisonvs Longitude

• Average line-of-sight magnetic field versus sine latitude observed in HMI synoptic map

Synoptic / Synchronic

• Features are stretched far from reference

Time-of-Day Variation - 01 UT and 13 UT