CDS Session NAM Dublin April Active Region Loop Studies in Oslo Olav Kjeldseth-Moe and Terje Fredvik Institute of Theoretical Astrophysics University of Oslo

CDS Session NAM Dublin April Prehistory … AR loops on east limb with LABP2W on 27 July 1996 First detection of large velocities in AR loops, 50 km/s Brekke, Kjeldseth- Moe and Harrison, Solar Physics 175, ,1997

CDS Session NAM Dublin April

4 Next … A program was started, to follow up on study of high velocities in active region loops, to see whether they were a common property of loops Initial observations with EJECT_V3 on 14 September 1997 EJECT_V3: Rasters 240” X 240” full coverage, cadence: 17 minutes 6 lines including O V 629 Å

CDS Session NAM Dublin April Pronounced time variability Rapid changes occur e.g. in less than 17 min, the cadence Even in a long lasting ( t > 3 h) loop system the change will be sudden, i.e. less than the time between two rasters Loops at different transition region temperatures are co-located

CDS Session NAM Dublin April Co-location of loops

CDS Session NAM Dublin April O_LOOP: General information NIS and GIS studies designed for studying active region loop structures outside the limb Observations have been part of several JOPs (e.g. JOP 75 and JOP 137), involving TRACE, SUMER, EIT and MDI, but have also run many times by themselves, i.e. with CDS only More than 95% of the data obtained during campaigns have been processed Present emphasis is on determining the temperature demarcation separating “strong” and “weak” activity in loop plasmas

CDS Session NAM Dublin April Oslo Active Region Studies O_LOOP1 – “high” cadence raster – the workhorse of the program O_LOOP2 – “context” raster with good temperature coverage O_LOOP3 - wide slit giving hyper fast monochromatic images at three wavelengths O_LOOP4 - same as O_LOOP1 with the slit staying in one position, for time studies O_LOOP5 - very high cadence raster (incomplete area coverage, stripes) O_LOOP10 and O_LOOP11 – GIS observations for improved temperature coverage at 0.5 MK

CDS Session NAM Dublin April Oslo Active Region Studies (2) Study Data Slit Step FOV Exp. Cadence First Number Name window # size time run of runs l x y (as) (as) (s) (m:s) ============================================== O_LOOP1 15x x :30 97/11/ O_LOOP2 32x x :45 97/11/13 91 O_LOOP3 90x x :22 97/11/13 5 O_LOOP4 15x x :15 00/10/24 2 O_LOOP5 15x x :02 00/10/ O_LOOP ( l ) 2 - 4x4 30 0:32 02/03/12 4 O_LOOP ( l ) 2 - 4x4 60 0:62 02/03/12 8 ==============================================

CDS Session NAM Dublin April Wavelength list Ion l (Å) T(K) #1 #2 #3 #4 #5 #10/11 ===================================== He I x x x x x O III x x x x O VI x O V x O V x x x x x Ne VI x x x x Ne VII x Mg VII x Mg IX x x x x x Mg X x Si IX x Si X x Si X x Fe XIV x Si XII x Fe XVI x x x x

CDS Session NAM Dublin April Number of runs Study O_LOOP O_LOOP O_LOOP3 5 O_LOOP4 2 O_LOOP O_LOOP10 O_LOOP11 4/6 0/2

CDS Session NAM Dublin April O_LOOP1 - Product

CDS Session NAM Dublin April O_LOOP3

CDS Session NAM Dublin April Loop motions from EIT

CDS Session NAM Dublin April O_LOOP5: Raster

CDS Session NAM Dublin April O_LOOP5: raster & movie

CDS Session NAM Dublin April Time variations MK

CDS Session NAM Dublin April Data reduction Data are always processed with the latest CDS software, i.e. the Component Fitting System (see CDS SW Note #47) Performs line profile fitting, allowing: a) interactive fitting of line profiles b) detailed inspection of the results c) automatic processing of large data sets An analysis definition (ADEF) is made for each line in each CDS study and used to process all observations of that study The ADEF contains: all line profile parameters, plus keywords describing calibrations to be performed, and units of result Profiles are assumed to be Gaussian; parameters include intensity, line shift and line width ADEF may be adjusted locally in regions with non-typical line parameters Final product: Parameters of fitted profile at each image element