Presentation on theme: "2007/12/08-10Hinode Workshop in China 1 XRT Analysis Software R. Kano (NAOJ) and XRT Teams."— Presentation transcript:
2007/12/08-10Hinode Workshop in China 1 XRT Analysis Software R. Kano (NAOJ) and XRT Teams
Hinode Workshop in China2 2007/12/08-10 Analysis Guide XRT Analysis Guide (XAG) is distributed in SSW as $SSW/hinode/xrt/docs/XAG.pdf. In the guide, …. For data analysis problems, contact xrt_manager[at]cfa.harvard.edu For science discussions, contact xrt_science[at]cfa.harvard.edu
Hinode Workshop in China3 2007/12/08-10 Outline of XRT Analysis Get Level-0 data Download Level-0 data from DARTS or other mirror sites. Define XRT FITS files (Level-0 data). Read file(s) Create Level-1 data(= Calibration) Calibration… Only for morphological studies, if necessary, touch-up the contamination spots. Create Level-2 data For example, to calculate temperature and emission measure Morphological studies are available. Studies of spatial and temporal variation are available. Studies of energetics are available.
Hinode Workshop in China4 2007/12/08-10 Get Level-0 data. Download Level-0 data from DARTS or other mirror sites. Downloaded FITS files are named as XRTYYYYMMDD_hhmmss.s.fits, and stored in the directory of YYYY/MM/DD/Hhh00. Define XRT FITS files (Level-0 data). Set the name of directory where the downloaded FITS files are stored as dir_name, then file=file_search(dir_name, '*.fits') Read file(s) read_xrt, file, index0, data0 which is identical with mreadfits, file, index0, data0. The unit of data0 is DN (data number), which corresponds to about 57 electrons.
Hinode Workshop in China7 2007/12/08-10 Selection of Images Important parameters in index index.date_obs : Start time of exposure. index.exptime : Exposure duration in sec. index.ec_fw1_ : Filter name in FW1. index.ec_fw2_ : Filter name in FW2. index.chip_sum : Spatial resolution in CCD pixel. index.rsize_col : Horizontal size in CCD pixel. index.rsize_row : Vertical size in CCD pixel. Example to select Ti/poly. images. mreadfits, file, index ss = where( (index.ec_fw1_ eq ‘Open’) and (index.ec_fw2_ eq ‘Ti_poly’) ) mreadfits, file(ss), index0, data0 FW2 FW1
Hinode Workshop in China8 2007/12/08-10 Create Level-1 data: Calibration Calibration xrt_prep, index0, data0, index1, data1 Data base ( or detailed model ) of dark images will be distributed through SSWDB in near future. For CCD-bias and dark subtraction & exposure normalization, it is almost the same with the following equations, if you have dark_image with the same exposure duration. data1 = ( data0 – dark_image ) / index0.exptime XRT images’ alignment xrt_jitter, index, off data_output = image_translate( data_input, off )
Hinode Workshop in China9 2007/12/08-10 To Download of Dark Images Recently we take dark images during observations at a low cadence (10min-a few hours) with the same FOV format. At this point, for better quantitative analysis, it is better to use dark images with the same FOV format taken during the observation. Caution: Exposure duration of dark images shown by index.exptime is meaningless, because no shutter motion. Accumulation duration shown by index.exccdex indicate the length of dark “exposure”.
Hinode Workshop in China13 2007/12/08-10 Create Level-1 data Only for morphological studies, if necessary, touch-up the contamination spots. xrt_tup_contam,index0,data0,index1,data1
Hinode Workshop in China14 2007/12/08-10 Create Level-2 data: Example of Filter-Ratio Method. Filter-Ratio Method xrt_teem, index1, data1[*,*,0], index1, data1[*,*,1], te, em, te_err, em_err ne = 0.5 em – 0.5 alog10(V), where V( cm 3 ) is the volume of the observing plasma. Narukage et al. 2008 (TBD). image taken with one filter image taken with the other filter logT(K)logVEM(cm -5 ) errors in log scale logNe(cm -3 ) It will be installed into SSW soon.
Hinode Workshop in China15 2007/12/08-10 Create Level-2 data: Caluculate XRT response Effective Area ea = xrt_eff_area( lambda ) The Chianti package is SSW is also useful to understand the XRT response. Temperature Response t_resp = xrt_flux( te, FW1_ID, FW2_ID, /DN) Filter-Ratio Model Function ratio = t_resp0 / t_resp1 Narukage et al. 2008 (TBD). It will be installed into SSW soon.
Hinode Workshop in China16 2007/12/08-10 Summary XRT software and database are distributed as SSW and SSWDB, although more progress of them is necessary. XRT Analysis Guide (XAG) is distributed in SSW as $SSW/hinode/xrt/docs/XAG.pdf. The programs related with the filter-ratio method will be distributed, just after we finish the on-orbit re-calibration of XRT. The results of on-orbit re-calibration will be submitted as “Narukage et al. 2008, Solar Physics”.
Hinode Workshop in China17 2007/12/08-10 Finally We would like to share to develop better software. When you create any useful programs, please let us know.