|
Документ взят из кэша поисковой машины. Адрес
оригинального документа
: http://hea-www.harvard.edu/PROS/PUG/node134.html
Дата изменения: Unknown Дата индексирования: Mon Oct 1 23:25:05 2012 Кодировка: Поисковые слова: merging galaxies |
The detect package contains several tasks which may be run seperately or all together (sequentially) by a script, LDETECT. Each task has an on-line HELP file, and a longer discussion is given in the on-line file EXPLAIN_DETECT. The current version of DETECT is based on the Einstein and ROSAT/HRI level 1 processing algorithms. It is a "sliding-box" routine which uses a detect cell and derives the background from a frame around the cell.
A clone of the "map detect" used in SASS processing is now available in xproto: "imdetect". In this case, the background is taken to be a constant rather than being measured in a frame around the detect cell (the so called 'ldetect', or 'local detect'). The other difference is that imdetect works on image files as well as qpoe files. NB: there was a bug in PROS 2.5 which caused imdetect to crash when using an image file. This bug was corrected in the patch PROS 2.5.1 (1998Apr01). See the help file for more details.
There are 5 basic tasks in the current DETECT package:
In addition, the following auxiliary tasks are provided:
In the examples below we give a minimal run to show the basic operation. Other parameters may be used by experimentation or by reading the help files.
EXAMPLE 1 - running LDETECT - ROSAT HRI
In this case we specified only the cellsize, leaving the default thresholds and default circle for the background measurement.
xp> ldetect qpoe file : xdata$rh110267.qp Output table root: rh110267 ROSAT HRI Cellsize in arcsecs - 6|9|12|24|36|48: 24 ... Running Cellmap ... xdata$rh110267.qp[bl=16] -> rh110267.imh add rh110267.imh,cellsize = 24 rh110267.imh updated xdata$rh110267.qp ... Running Snrmap ... Convolving 3x3 cells Convolving 5x5 cells Calculating Snrmap with equation: snrmap=(1.7777*cell3-frame)/((1.7777**2*cell3+oframe)**0.5) Writing Snrmap Image: rh110267_snr.imh ... Running Lpeaks ... src# logx logy physx physy cellx/y snr --------------------------------------------------------- 1 149.00 177.00 2384.00 2832.00 24 24 5.954 2 146.00 276.00 2336.00 4416.00 24 24 30.197 Writing to Output file: rh110267_ruf.tab ... Running Bkden ... Bkden region is circle 256.00 256.00 7.50' Bkden = 12.8558464 counts/arcmin**2 ... Running Bepos ... *** PI bands must be Respecified with input QPOE *** Input Qpoe: xdata$rh110267.qp bkden = 12.8558464 (cts/sq arc-min), 0.0008928 (cts/sq pixel) 2 Rough Position(s) Input src# ra dec physx physy cellcnts framecnts snr --------------------------------------------------------------------------- 1 22:08:38.4 45:31:24.2 2380.1 2829.1 95 67 5.3 2 22:08:41.4 45:44:33.4 2323.5 4407.7 1506 394 31.8 Writing 2 Sources to Output file: rh110267_pos.tab
EXAMPLE 2 - running the 5 components separately - ROSAT PSPC
de> cellmap
Input xray Qpoe: xdata$rp110590.qp Output xray image : rp110590_cmp ROSAT PSPC Cellsize in arcsecs - 30 [h/b]| 45 [s]| 60 [s/h/b]| 120 [s/h/b]: 30 Energy Band (soft|hard|broad) (broad): hard xdata$rp110590.qp[bl=20,pi=52:201][128:639,128:639] -> rp110590_cmp.imh add rp110590_cmp.imh,cellsize = 30 rp110590_cmp.imh updated xdata$rp110590.qp[pi=52:201] de> snrmap Input xray image : rp110590_cmp Output snrmap image [root_snr.imh]: rp110590 Convolving 3x3 cells Convolving 5x5 cells Calculating Snrmap with equation: snrmap=(1.7777*cell3-frame)/((1.7777**2*cell3+oframe)**0.5) de> lpeaks Input Snrmap Image: rp110590_snr Output Rough Positions Table: rp110590 src# logx logy physx physy cellx/y snr --------------------------------------------------------- 1 224.00 263.00 7020.00 7800.00 30 30 4.372 2 220.00 340.00 6940.00 9340.00 30 30 12.945 Writing to Output file: rp110590_ruf.tab xp> bkden Input Image: rp110590_cmp Region Descriptor (default): BOX(226,115,344.00,94.00) [This box was determined by examining the cellmap and finding a source free region.] Bkden region is BOX(226,115,344.00,94.00) Bkden = 0.6401532 counts/arcmin**2 xp> bepos.snr_thresh=3.5 xp> bepos *** PI bands must be Respecified with input QPOE *** Input qpoe file: xdata$rp110590.qp[pi=(41:240)] Field background density in cts/arcmin**2 (0.82384938001633): Input rough pos table: rp110590_ruf.tab Output bepos table file: rp110590 Input Qpoe: xdata$rp110590.qp[pi=52:201] bkden = 0.6401532 (cts/sq arc-min), 0.0000445 (cts/sq pixel) 2 Rough Position(s) Input src# ra dec physx physy cellcnts framecnts snr --------------------------------------------------------------------------- 1 22:08:37.8 45:31:46.7 7008.0 7794.9 41 19 4.3 2 22:08:41.6 45:44:45.4 6929.6 9352.5 1607 1865 11.9 Writing 2 Sources to Output file: rp110590_pos.tab
EXAMPLE using LMATCHSRC -
Two table files are output. The first (_unq.tab) is a unique list of all input detections where each has a unique row reference; the second file (_mch.tab) is the output of the match. This file is a match reference list with one row for each source. Match columns refer to the detections listed in the _unq.tab file.
Match sources from 4 runs of ldetect at different detect cell sizes.
de> lmatchsrc
Reference Qpoe file name: xdata$rh110267.qp
List of detect tables to match [_pos.tab]: rh12_pos,rh24_pos,rh36_pos,rh48_pos
Root name for Match Source table: rharlac
... Merging the list of input tables
... Sorting the list in y,x order
... Matching the detections into Sources
Avg ra Avg dec Avg x Avg y Best x Best y Src ref
(physical pixels) (physical pixels) (row #)
-----------------------------------------------------------------------------
1 22:08:38.4 45:31:24.3 2380.332 2829.285 2380.510 2829.540 3 2 1
2 22:09:01.3 45:37:14.3 1902.477 3531.475 1902.477 3531.475 4
3 22:08:41.4 45:44:33.4 2323.537 4407.728 2323.539 4407.733 6 8 7 5 9
Writing to Match Results table: rharlac_mch.tab
Writing to Match Reference table: rharlac_unq.tab