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.
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