SGP/NFOV/C1 - Head temp heater circuit failed

The head temp values were erratic.  The instrument was removed from service and found the 
head temp heater circuit failed in the full-on position frying the detectors.  Data are 
not useful.

Do not use data during this time period.

• Detector temperature(head_temp)
• Ambient Temperature(ambient_temp)
• Tube Temperature(tube_temp)
• Fields flagged by callang: 0 = No Flag ,(callang_flags)
• Uncalibrated Zenith Radiance(radiance)
• Raw counts from instrument before calibration(raw_counts)

• Fields flagged by callang: 0 = No Flag ,(callang_flags)
• Tube Temperature(tube_temp)
• Cosine solar zenith angle(cosine_solar_zenith_angle)
• Detector temperature(head_temp)
• Uncalibrated Zenith Radiance(radiance)
• Calibrated zenith radiance data corrected for changes in head temperature.(radiance_temp_cor)
• Raw counts from instrument before calibration(raw_counts)
• Ambient Temperature(ambient_temp)