ACIS Bad Pixels and Columns for FP Temperature of -120C

ACIS Bad Pixels and Columns for FP temperature = -120 C

R. Edgar and M. Markevitch (last update 2/21/05)
cxccal@cfa.harvard.edu

Previous releases:

Related:

Bad Pixels and Columns for -100C B. McNamara and A. Ware, 1/7/00
Hot Pixels in FI Devices (for -90C and -60C) M. Pivovaroff, 9/20/99 (postscript file)

R. Edgar, 2001 Jun 28:

In the process of making event lists for the ACIS background, Maxim Markevich has identified a number of bad pixels and/or columns on the ACIS chips operating at -120 C. This proposed list has been examined, compared with a similar list based on Bev LaMarr's examination of bias frames, and a final list was agreed to.

The details follow:

Making a bad pixel/bad column list:

[1] Look at Maxim's images by eye and flag bad columns and pixels, grading the columns strong/weak/very weak/node boundary/flight.

[2] make histograms vs. chipx and list columns greater than + 2 sigma. This is the mk_chipx_histo.csh script. Compare in detail. Also compare to Bev's criticisms. Edit list by hand (this procedure doesn't do very well at limited chipy extents, for instance).

[2a] Get everyone to agree on the list (Maxim, Bev, cc: Mark Bautz).

[3] Glenn asked for 1-1024 in chipy instead of 2-1023 as Maxim had.

[4] Turns out the tool adds padding around bad pixels/columns, so remove that from the list. Also add a flag field so I can remember what's going on, include everything, and then strip out only the real bad columns to send to Glenn.

[5] extract using

row < badpix_C_200922_full.rdb Note eq W or Note eq S or Note eq BP

for Glenn. Note column is S (strong) W (weak) VW (very weak), F (Flight), FB (Flight boundary), NB (Node boundary), or BP (bad pixel). This gives only the bad columns (strong or weak) and bad pixels, and no node boundaries and no next-to-bad columns.

The list of flight software excluded bad pixels is then added to this file, called badpix_C_200922.rdb.

Following is the file (in human-readable RDB format) delivered to SDS/Glenn Allen for generation of the CALDB entry:

badpix_2001_06_08_list.rdb (see notes to the table below).

M. Markevitch, 2003 May 13:

The above list has been made into the CALDB file acisD2000-01-29badpixN0001.fits (and its copies acisD2000-07-04badpixN0001, acisD2000-07-06badpixN0001, acisD2000-08-12badpixN0001).

Since its creation, new bad pixels and columns appeared. From searching grade-filtered event files for permanent bright pixels giving on average >0.1 cts/ks and for obvious permanent bad columns, the following were identified:

-------------------------
ccd_id chipx chipy
-------------------------
Starting from 2000-11-28:

6      766   501
8      518   1-1024 *
8      630   1-1024
8      874   1-1024
8      878   1-1024
8     1005   1-1024
8     1009   1-1024
(* date of first appearance for these columns is approximate)
-------------------------
Starting from 2002-01-23:

9      150   374
-------------------------
Starting from 2002-10-05:

4      885   460
5      383   586
5      357   303
-------------------------

No other permanent bad pixels or columns are seen as of the long ACIS-I and ACIS-S observations in March 2003. Adding the above new finds to the original -120C list, the following new lists were created, to be included in the CALDB and applied to the data as of the start date in the filename:

M. Markevitch, 2005 Feb 21:

The above tables have been updated with several new permanent hot pixels (not listed here), as well as the following:

1. "Shadow" columns seen in images of ECS and bright extended sources, which, according to Catherine Grant, are caused by anomalously large CTI:

-------------------------
ccd_id  chipx    chipy
-------------------------
0      302-304  176-1024
0      962-964    1-1024
1      990-992  240-1024
3       22- 25  890-1024
3      643-645  340-1024
6      603-603    1-1024
6      378-380    1-1024
6      437-439    1-1024
-------------------------

2. A number of bad columns that were previously deemed too faint for inclusion into the CALDB tables, but recently turned out to cause problems for some sensitive analyses. These columns are defined as follows: they are "clearly seen" in a 150-200 ks sky exposure, 0.2-1 kev image binned by x32 along CHIPY. The exception is S4 where I include only the brightest of these faint columns (because otherwise little chip area will be left).

As of 2000-01-29, these include the following columns (chipx):

ccd 0: 642 928 934
ccd 1: 8 76 325 399 425 585 724
ccd 2: 320 508 565 631 887
ccd 3: 180 532 978
ccd 4: 53 120 514 558 583 723 925
ccd 6: 9 182 579 726
ccd 7: 66 (chipy: 800-1024)
ccd 8: 13 51 54 77 92 112 487 489 506 518 532 904 957 959 994 1005
ccd 9: 81 956

As of 2000-11-28, the following colums (mostly same as above):

ccd 0: 538 642 928 934
ccd 1: 8 53 76 325 399 425 435 724
ccd 2: 196 508 565 631 887 964
ccd 3: 180 532
ccd 4: 53 120 514 558 583 723 925
ccd 6: 9 182 579 726
ccd 7: 66 (chipy: 800-1024)
ccd 8: 13 92 178 487 489 506 532 904 957 959 961 991 994 998
ccd 9: 81 114 407 956

3. It has also been agreed that it is not worth creating a new CALDB badpix table whenever a new permament bad pixel appears. Instead, any new pixel may be included retroactively into the nearest existing table (that is, if we have a table whose start date is 2000-11-28, and a new pixel appeared on 2004-11-05, it goes into that table). The advantage is consistency between the bad pixels excluded from the ACIS background event files and those excluded from the archival data. So the following existing files should no longer be used:

acisD2002-01-23badpixN0001
acisD2002-10-05badpixN0001

The new pixels from those files are included into the 2000-11-28 file below.

These are the resulting 2 files covering the entire -120C epoch, which include the above changes:

The start dates are same as those for the ACIS background datasets (almost, but the difference is negligible).

4. Note that it has been decided not to include into the CALDB bad pixel tables the chip edges CHIPY<9 vignetted by frame store structure (they are seen as shadows in sky images). This effect will be included into the QEU maps.

For quick reference, below is the list of bad pixels and columns in the latest observations (file acisD2000-11-28badpixN0002). CHIPX0, CHIPX1, CHIPY0, and CHIPY1 are the boundaries of a rectangle defining a region of bad pixels; for a single pixel, CHIPX0=CHIPX1 and CHIPY0=CHIPY1. Notes: F = excluded onboard, BP = bad pixel (when not obvious), CTI = "shadow" column with anomalous CTI.

---------------------------------------------
 CCD_ID CHIPX0  CHIPX1  CHIPY0  CHIPY1  Note
---------------------------------------------
 0	2	4   	1	1024
 0	31	31    	1	1024
 0	71	73    	1	1024	F
 0	79	82    	1	1024
 0	95	95    	1	1024
 0	165	165   	1	1024
 0	226	226   	1	1024
 0	256	257   	1	1024
 0	484	484   	1	1024
 0	512	514   	1	1024
 0	580	580   	1	1024
 0	605	605	1	1024
 0	768	769   	1	1024
 0	1009	1011  	1	1024
 0	1014	1016  	1	1024
 0	303	303	253	253	F
 0	302	304	176	1024	CTI
 0	962	964	1	1024	CTI
 0	538	538	1	1024
 0	642	642	1	1024
 0	928	928	1	1024
 0	934	934	1	1024
 1	54	54    	1	1024
 1	97	97    	1	1024
 1	192	192   	1	1024
 1	256	257   	1	1024
 1	303	303   	1	1024	F
 1	409	409   	1	1024	F
 1	512	513   	1	1024
 1	521	521   	1	1024
 1	558	558   	1	1024
 1	583	583   	1	1024
 1	691	691   	1	1024
 1	704	704   	1	1024
 1	768	769   	1	1024
 1	1007	1009  	1	1024
 1	533	533	33	33
 1	990	992	240	1024	CTI
 1	8	8  	1	1024
 1	53	53  	1	1024
 1	76	76  	1	1024
 1	325	325  	1	1024
 1	399	399  	1	1024
 1	425	425  	1	1024
 1	435	435  	1	1024
 1	724	724  	1	1024
 2	23	23  	1	1024
 2	127	127 	1	1024
 2	133	135 	1	1024
 2	162	162	1	1024
 2	218	218	1	1024
 2	256	257 	1	1024
 2	437	437 	1	1024
 2	512	513 	1	1024
 2	548	548 	1	1024
 2	553	553	1	1024
 2	558	560 	1	1024
 2	570	572 	1	1024
 2	671	671 	1	1024
 2	699	699 	1	1024
 2	768	769 	1	1024
 2	818	818 	1	1024
 2	930	930 	1	1024
 2	1017	1019	1	1024
 2	196	196	1	1024
 2	508	508	1	1024
 2	565	565	1	1024
 2	631	631	1	1024
 2	887	887	1	1024
 2	964	964	1	1024
 3	256	257	1	1024
 3	474	474	1	1024
 3	492	492	1	1024
 3	512	513	1	1024
 3	768	769	1	1024
 3	 22	 25	890	1024	CTI
 3	643	645	340	1024	CTI
 3	180	180	1	1024
 3	532	532	1	1024
 4	885	885	460	460
 4	9	9  	1	1024
 4	38	40 	1	1024
 4	106	108	1	1024
 4	123	123	1	1024
 4	162	162	1	1024
 4	196	198	1	1024
 4	256	257	1	1024
 4	362	364	1	1024
 4	487	489	1	1024
 4	506	508	1	1024
 4	512	514	1	1024
 4	544	544	1	1024
 4	585	587	1	1024
 4	601	601	1	1024
 4	627	629	1	1024
 4	740	740	1	1024
 4	768	769	1	1024
 4	839	839	1	1024
 4	861	863	1	1024
 4	875	877	1	1024
 4	890	890	1	1024
 4	955	957	1	1024
 4	967	969	1	1024
 4	1018	1018	532	532
 4	53	53	1	1024
 4	120	120	1	1024
 4	558	558	1	1024
 4	583	583	1	1024
 4	723	723	1	1024
 4	925	925	1	1024
 5	232	234	313	322
 5	233	251	312	314
 5	256	257	1	1024
 5	512	513	1	1024
 5	670	672	1	1024
 5	768	769	1	1024
 5	161	161	206	206
 5	226	226	564	564
 5	341	341	427	427
 5	357	357	303	303
 5	367	367	497	497
 5	607	607	281	281
 5	716	716	718	718
 5	1022	1024	166	167
 5	383	383	585	586	F+BP
 5	792	792	351	351	F
 5	498	498	59	59
 5	655	655	652	652
 6	766	766	501	501
 6	538	538	8	8
 6	220	220	59	59
 6	1004	1004	5	5
 6	57	59  	1	1024
 6	256	257 	1	1024
 6	512	513 	1	1024
 6	584	586 	1	1024
 6	683	683 	1	1024
 6	768	769 	1	1024
 6	1003	1003 	1	1024
 6	603	603	1	1024	CTI
 6	378	380	1	1024	CTI
 6	437	439	1	1024	CTI
 6	9	9	1	1024
 6	182	182	1	1024
 6	579	579	1	1024
 6	726	726	1	1024
 7	426	426	316	316
 7	256	257 	1	1024
 7	496	498	441 	1024	F
 7	496	498	1   	40
 7	512	513 	1	1024
 7	738	738	973	1024
 7	768	769 	1	1024
 7	66	66	800	1024
 8	2	2   	1	1024
 8	5	5   	1	1024
 8	20	20  	1	1024
 8	25	25  	1	1024
 8	32	34  	1	1024
 8	99	99  	1	1024
 8	171	171 	1	1024
 8	256	257 	1	1024
 8	453	453 	1	1024
 8	508	508	1	1024
 8	512	514 	1	1024
 8  	516  	516 	1 	1024
 8  	518  	518 	1 	1024
 8	540	542 	1	1024
 8  	630  	630 	1 	1024
 8	632	632 	1	1024
 8	768	769 	1	1024
 8  	874  	874 	1 	1024
 8	876	876 	1	1024
 8  	878  	878 	1 	1024
 8	910	910 	1	1024
 8	951	953 	1	1024
 8	966	966 	1	1024
 8 	1005 	1005 	1 	1024
 8	1007	1007	1	1024
 8 	1009 	1009 	1 	1024
 8	603	603	23	23
 8	13	13 	1 	1024
 8	92	92 	1 	1024
 8	178	178 	1 	1024
 8	487	487 	1 	1024
 8	489	489 	1 	1024
 8	506	506 	1 	1024
 8	532	532 	1 	1024
 8	904	904 	1 	1024
 8	957	957 	1 	1024
 8	959	959 	1 	1024
 8	961	961 	1 	1024
 8	991	991 	1 	1024
 8	994	994 	1 	1024
 8	998	998 	1 	1024
 9	150	150	374	374
 9	93 	93	1	1024
 9	256	257	1	1024
 9	328	328	1	1024
 9	408	410	1	1024
 9	512	513	1	1024
 9	768	769	1	1024
 9	962	962	1	1024
 9	81	81	1	1024
 9	114	114	1	1024
 9	407	407	1	1024
 9	956	956	1	1024

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