CORONAL HOLES (CHS) ARE MOST COMMONLY DEFINED AS LONG-LIVED REGIONS OF REDUCED INTENSITY IN EUV IMAGES AND KNOWN TO BE THE SOURCE OF THE FAST SOLAR WIND. RECENT ANALYSIS OF THE SPECTRAL CHARACTERISTICS OF CHS USING DATA FROM THE INTERFACE REGION IMAGING SPECTROGRAPH (IRIS) AND THE EXTREME ULTRAVIOLET IMAGING SPECTROMETER (EIS) ON HINODE BELIES THEIR APPARENT UNIFORMITY IN IMAGING DATA. DESPITE THE TYPICAL ASSERTION THAT CHS ARE THE SOURCE OF THE FAST SOLAR WIND EIS MEASUREMENTS SHOW REGIONS WITHIN A CH OF SLOW-WIND COMPOSITION IN THE CORONA. THE SPECTRAL SIGNATURES OF THESE REGIONS EXTEND TO THE CHROMOSPHERE AS EVIDENCED IN THE MG II LINES MEASURED BY IRIS SUGGESTING THE DIFFERENCES ARE A RESULT OF EFFECTS IN THE LOWER SOLAR ATMOSPHERE. THIS RESEARCH PROJECT AIMS TO INVESTIGATE THE SOURCE REGIONS OF FAST AND SLOW SOLAR WIND WITHIN CHS CHALLENGING THE PARADIGM THAT CHS ARE THE UNIFORM SOURCE OF THE HIGH-SPEED SOLAR WIND. WE WILL INVESTIGATE THE DEGREE OF VARIABILITY WITHIN A CH AND CONNECT THE PROPERTIES OF CHS ACROSS A WIDE RANGE OF ATMOSPHERIC HEIGHTS. OUR ANALYSIS OF CH PROPERTIES WILL EMPLOY DATA FROM SEVERAL NASA MISSIONS. SPECTROSCOPIC DATA OF THE CHROMOSPHERE AND TRANSITION REGION WILL BE PROVIDED BY IRIS OBSERVATIONS AND CORONAL SPECTROSCOPY WILL COME FROM THE OBSERVATIONS OF EIS. WE WILL ALSO USE THE EUV DATA OF THE ATMOSPHERIC IMAGING ASSEMBLY (AIA) AND THE MAGNETOGRAMS FROM THE HELIOSEISMIC AND MAGNETIC IMAGER (HMI) ON BOARD THE SOLAR DYNAMICS OBSERVATORY (SDO) TO IDENTIFY CHS. WE WILL USE THE CORONAL HOLE AUTOMATED RECOGNITION AND MONITORING (CHARM) CODE TO IDENTIFY AND PARAMETERIZE THE CHS IN THIS STUDY AND THE MINOR STORM (MIST) ALGORITHM TO LINK THE CHS TO THE SOLAR WIND. THESE CODES UTILIZE FULL-SUN IMAGES FROM AIA AND HMI. THE SPECTROSCOPIC MEASUREMENTS WILL COME FROM IRIS AND EIS BOTH OF WHICH HAVE LIMITED FIELDS OF VIEW SUCH THAT AN ENTIRE CH CANNOT BE OBSERVED WITH A SINGLE POINTING. WE WILL USE DATA FROM SPECIAL MOSAICKED OBSERVING ROUTINES THAT COVER THE ENTIRE SOLAR DISK TO ANALYZE THE PROPERTIES ACROSS THE ENTIRE EARTH-FACING CH. THESE UNIQUE DATA SETS PROVIDE THE FIRST FULL SUN SPECTROSCOPIC MEASUREMENTS OF CHS FROM CHROMOSPHERE TO CORONA. EIS SAMPLES A WIDE RANGE OF IONS WHICH WILL ALLOW US TO DETERMINE TEMPERATURE DENSITY AND DOPPLER SPEEDS THROUGHOUT THE CORONA. WE WILL ALSO DERIVE THE PLASMA COMPOSITION BY ANALYZING THE EMISSION ACROSS DIFFERENT ELEMENTS. SIMULTANEOUSLY IRIS WILL PROVIDE OBSERVATIONS OF SEVERAL EMISSION LINES IN THE CHROMOSPHERE AND TRANSITION REGION ALLOWING US TO CONNECT PLASMA PROPERTIES AT THESE LOW ATMOSPHERIC HEIGHTS WITH THE CORONA. THIS RESEARCH IS OF DIRECT RELEVANCE TO THE SCIENCE GOALS OF IRIS HINODE AND SDO. UNDERSTANDING ENERGY TRANSPORT THROUGH THE DIFFERENT LAYERS OF THE SOLAR ATMOSPHERE ARE PRIME DRIVERS OF EACH OF THESE MISSIONS. THE PRIMARY SCIENCE GOAL OF IRIS IS "TO CONNECT THE PHYSICS OF PHOTOSPHERE AND CHROMOSPHERE TO THAT OF TR AND LOW CORONA" WHICH OUR STUDY ADDRESSES BY INVESTIGATING CH PROPERTIES FROM THE PHOTOSPHERE (USING HMI DATA) THROUGH THE CHROMOSPHERE AND TR (WITH IRIS) AND INTO THE CORONA (EIS AND AIA DATA). IN ADDITION OUR INVESTIGATION OF THE SOURCE REGIONS OF THE SOLAR WIND ADDRESSES THE HIGH-LEVEL SCIENCE GOAL OF THE HELIOPHYSICS DECADAL SURVEY TO "DETERMINE THE INTERACTION OF THE SUN WITH THE SOLAR SYSTEM".
$524,409FY2020National Aeronautics and Space AdministrationNASA
University Corporation For Atmospheric Research