How to Download Chandra Data from the Archive
![[CXC Logo]](../../imgs/cxc-logo.gif){kind=logo}
CIAO 4.5 Science Threads
Overview
Synopsis:
The Chandra Data Archive contains over 11,000 public-domain datasets, which consist of all observations for which the proprietary period has expired, as well as calibration data.
This thread explains the two Data Archive interfaces: WebChaSeR and chaser. Additionally, there are command-line scripts for finding and downloading publicly-available Chandra data from the Archive: find_chandra_obsid and download_chandra_obsid. Please note that proprietary data cannot be accessed with these scripts.
The thread currently does not describe how to use the Chandra Footprint Service to search and download publicly-available observations.
Purpose:
To illustrate several methods of downloading ObsID 1843 (ACIS-I, G21.5-0.9), which is used in the Introductory CIAO Threads.
Last Update: 4 Apr 2013 - ChaSer is retired. WebChaser now supports individual data product downloads and the ability to upload a list of search criteria.
Contents
- What data files do I need for my analysis?
- Using the download_chandra_obsid script
- Using the find_chandra_obsid script
- Using WebChaSeR
- Chaser (retired)
- FTP and Unpack the Data
- History
- Images
What data files do I need for my analysis?
The standard data distribution arranges the data products such that the products necessary for most analyses (e.g. the CIAO threads) are in the primary directory. If you are interested in reprocessing your data, for example, you will also need the level 1 files, which are in the secondary directory.
Each of the threads also includes a list of the specific files needed to run it.
If you are unsure what analyses you will be doing, downloading both the primary and secondary data packages ensure that you will have any file you might need.
Using the download_chandra_obsid script
The download_chandra_obsid script provides a simple command-line interface to the Chandra Data Archive. It requires only the ObsID that you wish to download:
unix% download_chandra_obsid 1843
Each file that is downloaded will be displayed on screen, giving the type, format, and filesize before a progress bar of # marks (each # mark indicates 10% of the file). Once the file has been downloaded, an average rate is displayed for the download. (This output can be turned off with the "-q" or "--quiet" flags.)
Downloading files for ObsId 1843, total size is 67 Mb.
Type Format Size 0........H.........1 Download Time Average Rate
---------------------------------------------------------------------------
vv pdf 78 Kb #################### < 1 s 1593.2 kb/s
oif fits 23 Kb #################### < 1 s 461.3 kb/s
sum html 2 Kb #################### < 1 s 32.2 kb/s
sum ps 2 Mb #################### < 1 s 10615.7 kb/s
sum html 4 Kb #################### < 1 s 84.5 kb/s
sum html 3 Kb #################### < 1 s 56.1 kb/s
cntr_img fits 236 Kb #################### < 1 s 3225.8 kb/s
cntr_img jpg 871 Kb #################### < 1 s 9827.2 kb/s
evt2 fits 17 Mb #################### 2 s 11355.7 kb/s
full_img fits 80 Kb #################### < 1 s 1556.3 kb/s
full_img jpg 77 Kb #################### < 1 s 1353.9 kb/s
src2 fits 9 Kb #################### < 1 s 172.5 kb/s
src_img jpg 78 Kb #################### < 1 s 1544.3 kb/s
bpix fits 11 Kb #################### < 1 s 201.9 kb/s
fov fits 6 Kb #################### < 1 s 109.5 kb/s
eph1 fits 281 Kb #################### < 1 s 5580.8 kb/s
asol fits 2 Mb #################### < 1 s 10743.0 kb/s
aoff fits 1005 Kb #################### < 1 s 9853.0 kb/s
evt1 fits 35 Mb #################### 3 s 11393.0 kb/s
flt fits 7 Kb #################### < 1 s 141.0 kb/s
msk fits 5 Kb #################### < 1 s 99.3 kb/s
mtl fits 344 Kb #################### < 1 s 7018.1 kb/s
soff fits 4 Kb #################### < 1 s 76.0 kb/s
stat fits 290 Kb #################### < 1 s 5755.9 kb/s
bias fits 426 Kb #################### < 1 s 8464.1 kb/s
bias fits 494 Kb #################### < 1 s 8866.2 kb/s
bias fits 430 Kb #################### < 1 s 8381.4 kb/s
bias fits 423 Kb #################### < 1 s 8611.5 kb/s
bias fits 427 Kb #################### < 1 s 8503.9 kb/s
bias fits 427 Kb #################### < 1 s 8425.0 kb/s
pbk fits 4 Kb #################### < 1 s 74.9 kb/s
vv pdf 2 Mb #################### < 1 s 10822.3 kb/s
eph1 fits 6 Kb #################### < 1 s 127.7 kb/s
eph1 fits 274 Kb #################### < 1 s 5156.1 kb/s
eph1 fits 258 Kb #################### < 1 s 5195.1 kb/s
osol fits 351 Kb #################### < 1 s 6888.5 kb/s
aqual fits 148 Kb #################### < 1 s 2982.9 kb/s
osol fits 341 Kb #################### < 1 s 6967.2 kb/s
osol fits 356 Kb #################### < 1 s 6790.7 kb/s
Total download size for ObsId 1843 = 67 Mb
Total download time for ObsId 1843 = 7 s
The script also allows you to download multiple ObsIDs at one time by supplying a comma-separated list:
unix% download_chandra_obsid 1842,1843,459
or to download selected data files:
unix% download_chandra_obsid 1842,1843 evt2,asol
Refer to the help file for further details.
The data files are now ready to be used in CIAO. For a description of the files, read the Introduction to the Data Products thread.
Using the find_chandra_obsid script
The find_chandra_obsid script lets you search the publicly-available data in the Chandra Data Archive from the command line. It can be used to search by object name - using the CADC Name Resolver - or by position. First we try by name, but find that the resolver does not recognize the name:
unix% find_chandra_obsid G21.5-0.9 # find_chandra_obsid (15 February 2012): ERROR No position found matching the name 'G21.5-0.9'. unix% find_chandra_obsid G21.5-09 # find_chandra_obsid (15 February 2012): ERROR No position found matching the name 'G21.5-09'.
so we give the source location explicitly (as there are many matches for this calibration target most have them have been removed from the display below); note that the declination value includes both ' and " characters which involves an awkward combination in this tcsh example
unix% find_chandra_obsid "18h 33m 33.50s" "-10d 34' 06.70"'"' # obsid sepn inst grat time obsdate piname target 142 0.0 HRC-I NONE 30.5 2000-02-16 Calibration G21.5-0.9 143 0.0 HRC-I NONE 15.2 1999-09-04 Calibration "G21.5-0.9 [HRC-I, Offsets=0,0,0]" 144 0.0 HRC-I NONE 30.2 2000-09-01 Calibration "G21.5-0.9 [HRC-I, Offsets=0,0,0]" 158 0.0 ACIS-I NONE 9.8 1999-08-25 Calibration "G21.5-0.9 [Chip I1, T=100, Offsets=-3,-5,0 Off-ax]" 159 0.0 ACIS-S NONE 15.0 1999-08-23 Calibration "G21.5-0.9 [Chip S3, T=100, Offsets=0,0,0 Std Cand]" 160 0.0 ACIS-I NONE 9.8 1999-08-25 Calibration "G21.5-0.9 [Chip I0, T=100, Offsets=5,-5,0 Off-ax]" 161 0.0 ACIS-I NONE 9.8 1999-08-25 Calibration "G21.5-0.9 [Chip I2, T=100, Offsets=5,3,0 Off-ax]" 162 0.0 ACIS-I NONE 13.2 1999-08-27 Calibration "G21.5-0.9 [Chip I3, T=100, Offsets=-1,1,0 Std Can]" 163 23.5 ACIS-S NONE 10.0 1999-08-15 Calibration "G21.5-0.9 [Chip S0, T=100, Offsets=23,0,0]" 164 15.0 ACIS-S NONE 9.8 1999-08-15 Calibration "G21.5-0.9 [Chip S1, T=100, Offsets=15,0,0]" 165 0.0 ACIS-S NONE 9.8 1999-08-23 Calibration "G21.5-0.9 [Chip S2, T=100, Offsets=6,0,0]" ... 1840 0.0 ACIS-S NONE 7.8 2000-09-02 Calibration "G21.5-0.9 [Chip S3, T=120, Offsets=-1,5,-4]" 1841 0.0 ACIS-I NONE 8.1 2000-09-01 Calibration "G21.5-0.9 [Chip I3, T=120, Offsets=-1,10,5]" 1842 0.0 ACIS-I NONE 7.5 2000-09-02 Calibration "G21.5-0.9 [Chip S3, T=120, Offsets=-1,15,0]" 1843 0.0 ACIS-I NONE 8.0 2000-09-02 Calibration "G21.5-0.9 [Chip S3, T=120, Offsets=-1,20,-4]" ...
Positions can be supplied in a range of common formats for RA and Dec - e.g. as decimal degrees or various sexagesimal forms - as shown in further examples.
There are several ways to filter this output:
-
Use the limited filtering capabilities of the script (the instrument and grating parameters):
unix% find_chandra_obsid 278.390 -10.57 instrument=hrci # obsid sepn inst grat time obsdate piname target 142 0.1 HRC-I NONE 30.5 2000-02-16 Calibration G21.5-0.9 143 0.1 HRC-I NONE 15.2 1999-09-04 Calibration "G21.5-0.9 [HRC-I, Offsets=0,0,0]" 144 0.1 HRC-I NONE 30.2 2000-09-01 Calibration "G21.5-0.9 [HRC-I, Offsets=0,0,0]" 1406 0.1 HRC-I NONE 30.1 1999-10-25 Calibration "G21.5-0.9 [HRC-I, Offsets=0,0,0]" ...
-
Write the output to a file and then use the CIAO DataModel tools; for example:
unix% find_chandra_obsid 18:33:33.5 -10:34:7 > matches.txt unix% dmlist matches.txt counts 102 unix% dmlist matches.txt"[sepn<1,inst=ACIS-I]" counts 40 unix% dmlist matches.txt"[sepn<1,inst=ACIS-I,time>10][cols obsid,time]" data,clean # obsid time 162.0 13.20 1233.0 14.20 5158.0 10.10 1552.0 10.40The detail parameter can be changed to the all setting to have more columns written out (e.g. the target position), or obsid if you only want the observation id.
Once you have the observation ids you want you can use download_chandra_obsid to download them. Alternatively you can set the download parameter of the script to be asked whether each matching ObsId should be downloaded (download=ask), or to automatically download all matching ObsIds (download=all). The latter option should be used carefully as it is easy to accidentally download a lot of data!
As an example, here we look for HRC-I observations to download; the list of matching observations is given and then we are asked whether we wish to download each set:
unix% find_chandra_obsid '18 33 34' '-10 34' inst=hrci download=ask
There were 18 matching observations:
1/18: Obsid=142 Sepn=0.2 Inst=HRC-I Grat=NONE Exp=30.5 ObsDate=2000-02-16
PI=Calibration Target=G21.5-0.9
2/18: Obsid=143 Sepn=0.2 Inst=HRC-I Grat=NONE Exp=15.2 ObsDate=1999-09-04
PI=Calibration Target=G21.5-0.9 [HRC-I, Offsets=0,0,0]
...
17/18: Obsid=10648 Sepn=0.2 Inst=HRC-I Grat=NONE Exp=10.2 ObsDate=2009-02-17
PI=Calibration Target=G21.5-09
18/18: Obsid=13091 Sepn=0.2 Inst=HRC-I Grat=NONE Exp=10.2 ObsDate=2011-05-30
PI=Calibration Target=G21.5-09
Use h to get help on the download options.
1/18: Obsid=142 Sepn=0.2 Inst=HRC-I Grat=NONE Exp=30.5 ObsDate=2000-02-16
PI=Calibration Target=G21.5-0.9
Download [y, n, q, a, h]: h
Download options are:
y - download this ObsId
n - do not download this ObsId
q - do not download this or the remaining 17 ObsIDs
a - download this ObsId and the remaining 17 ObsIDs
h - display this information
Download [y, n, q, a, h]: n
2/18: Obsid=143 Sepn=0.2 Inst=HRC-I Grat=NONE Exp=15.2 ObsDate=1999-09-04
PI=Calibration Target=G21.5-0.9 [HRC-I, Offsets=0,0,0]
Download [y, n, q, a, h]:
...
From this point you can decide whether to download each observation, and once this is finished the download will begin.
Using WebChaSeR
WebChaSeR is the web interface to the Chandra Data Archive. It allows users to browse the observation catalog with a variety of search criteria, to display preview images, and to download the data tarfiles.
Unlike download_chandra_obsid, WebChaSeR doesn't allow you to select specific files for download. You can only select complete packages of primary and secondary products.
1. Browse
Chandra Archive data may be browsed using any of the fields in WebChaSeR, such as Target Name, Instrument, Grating, ObsID, and Category. Since we are interested in an ACIS-I observation of G21.5-0.9, highlight the appropriate Instrument (ACIS-I) and Grating (NONE) and enter the Target Name. In the "Customize Output" section at the bottom of WebChaSeR, change the Sort Order to "Observation ID".
Figure 1 shows the completed form.
![[Thumbnail image: The Instrument (ACIS-I) and Grating (NONE) options are highlighted in the WebChaSeR webpage and the Target Name is set to "G21.5-0.9".]](webform.png)
[Version: full-size]
Figure 1: The completed WebChaSeR form to search for ACIS-I observations of G21.5-0.9
Searching for ACIS-I observations of G21.5-0.9.
Click the "Search" button in the upper left corner of the form to start the search.
2. Select
The Search Results window brings up all the observations that match our search criteria, as shown in Figure 2.
![[Thumbnail image: The Search Results page lists all results of the search for ACIS-I observations of G21.5-0.9]](webmatch.png)
[Version: full-size]
Figure 2: The WebChaSeR Search Results page
Search results may be sorted by the "Order By..." menu.
The default number of rows returned in WebChaSeR is 50. If your search matches more than 50 observations, a message will be shown in the bottom left of the results page: 99 observations found, 50 displayed in this screenshot (Figure 2). Use the "Change Search Criteria" link to narrow the search or to increase the Row Limit value.
Click on ObsID 1843 to highlight the row. After doing so one may:
-
Use the "Details" link to display specifics about the observation, e.g. general observation parameters, ACIS-specific parameters, and any observation contraints.
-
Use the "V&V" link to read the Verification and Validation report.
-
Click on the "Images" link to view and download preview images. Use the "Image types" subnavigation to cycle through available images.
-
Use the "Back to Search Results" button to return to the previous page, allowing you to browse other observations.
When you are ready to download the dataset, make sure
the ObsID(s) are you interested in are checked off in
the search results page.
By default, both the primary and
secondary products (Figure 3) in WebChaSeR. Uncheck
either option if you don't wish to download both. ![[New]](../../imgs/new.gif)
Users
can also request a custom package that may include level 0 and level 1.5
data products not previously accessible via this interface.
![[Thumbnail image: Both the primary and secondary package options are checked by default.]](webpkg.png)
[Version: full-size]
Figure 3: WebChaSeR package selection
WebChaSeR now allows you to select only certain files with the Custom Package option.
The selections are submitted using the "Add to Retrieval List" button. Proceed to the next step.
3. Retrieve
Use the "Browse Products" button to view the observations and data products submitted for selection (Figure 4). At the bottom of the list, the total number of files and combined filesize is listed: "Total: 28 files, 124,033,470 bytes uncompressed. (Note: Downloaded data will be compressed to about 50-70% of this size.) ".
![[Thumbnail image: The retrieval list shows which files will be downloaded.]](webretlist.png)
[Version: full-size]
Figure 4: WebChaSeR retrieval list
There are 35 files in the primary and secondary product packages for this observation.
Use the "Retrieval List" link in the upper right to go back to the Retrieval List, then click the "Retrieve Products" button to start the retrieval process (Figure 5).
The files are compiled into a tarred package which is placed onto the anonymous FTP server (cdaftp.harvard.edu). If you provide your email address, you will receive an email when the tarfile is ready for download:
To: me@awesome.edu Date: Thu, 04 Apr 2013 14:39:46 -0400 Subject: Chandra Data Notification Your Chandra data are ready to be retrieved via anonymous ftp at cdaftp.cfa.harvard.edu in the directory /pub/stage/RYayl7LI. Files: total 82800 -r--r--r-- 1 arcpub2 dbm_dev 84613120 Apr 4 14:39 package_27906_130404143929.tar
![[Thumbnail image: The future location of the tarfile is listed, as well as a field for supplying your email address.]](webdownload.png)
[Version: full-size]
Figure 5: Retrieval Results screen
Make note of the FTP location of the tarfile, or enter your email address to have it sent to you.
Next, follow the instructions in the FTP and Unpack the Data section.
Chaser (retired)
(1 Apr 2013)
The downloadable Chaser Java application has been discontinued.
Users can use WebChaSeR to retrieve all the same data products
as well as batch searches.
FTP and Unpack the Data
The download_chandra_obsid script downloads the files into the current working directory. If you used WebChaSeR or chaser, you need to get the tarfile from Archive anonymous FTP server and unpacke it.
In this example, we use the name of the tarfile created by WebChaSeR: . The name and location of your tarfile will be different.
There are several options for downloading the tarfile:
-
Use wget from the command line:
unix% wget ftp://cdaftp.cfa.harvard.edu/pub/stage/RYayl7LI/package_27906_130404143929.tar --2013-04-04 14:45:17-- ftp://cdaftp.cfa.harvard.edu/pub/stage/RYayl7LI/package_27906_130404143929.tar => `package_27906_130404143929.tar' Resolving cdaftp.cfa.harvard.edu... 131.142.198.68 Connecting to cdaftp.cfa.harvard.edu|131.142.198.68|:21... connected. Logging in as anonymous ... Logged in! ==> SYST ... done. ==> PWD ... done. ==> TYPE I ... done. ==> CWD /pub/stage/RYayl7LI ... done. ==> SIZE package_27906_130404143929.tar ... 84613120 ==> PASV ... done. ==> RETR package_27906_130404143929.tar ... done. Length: 84613120 (81M) 100%[======================================>] 84,613,120 66.9M/s in 1.2s 2013-04-04 14:45:20 (66.9 MB/s) - `package_27906_130404143929.tar' saved [84613120] -
Open the ftp link in your web browser and use the "Save Link As..." (or similar) menu option to save the tarfile.
-
Log in to the anonymous FTP server and get the file:
unix% ftp cdaftp.harvard.edu % ftp cdaftp.harvard.edu Connected to cdaftp.harvard.edu (131.142.198.68). 220-Warning - Computer Use Policy in Effect Unauthorized access and use of this computer is a criminal violation of the Computer Fraud and Abuse Act (18 U.S.C. Sec. 1030). The responsibilities of all users of this system are described in Smithsonian Directive 931 (http://www.cfa.harvard.edu/do/sd931.pdf). Use of this computer and any other CfA IT assets implies an acceptance of the terms and conditions stated in SD 931. Any violation of these policies should be reported to syshelp@head.cfa.harvard.edu ----------------------------------------------------------------------- 220 Chandra Public FTP Archive cdaftp.cfa.harvard.edu Name (cdaftp.harvard.edu:user): ftp 331 Anonymous login ok, send your complete email address as your password Password: me@awesome.edu 230- Welcome to the Chandra Data Archive This server is cdaftp.cfa.harvard.edu If your FTP client crashes or hangs shortly after login please try using a dash (-) as the first character of your password. This will turn off the informational messages that may be confusing your FTP client. Publicly available files are in /pub Problems with this ftp site? Contact arcops@head.cfa.harvard.edu +---------------------------------------------------------------+ | | | This ftp site is the anonymous ftp version of the CDA. | | It contains all primary and secondary products of all | | public Chandra observations and is being kept up-to-date | | in real time. That means that observations that are | | released to the public are available from this ftp archive | | almost immediately and that old data versions are replaced | | by new, reprocessed ones as soon as they are released. | | | | For further information, please consult the file 00README. | | | | Mirror site opportunities: see the file 00README. | | | +---------------------------------------------------------------+ +---------------------------------------------------------+ | | | Data packages created by WebChaSeR can be found | | here in the directory provided by these archival | | search and retrieval tools. | | | | PLEASE NOTE: | | | | If the directory provided to you by WebChaSeR appears| | to be empty, this is a sign that your tar file is | | not yet ready. Please try again in a little while. | | | +---------------------------------------------------------+ 230 Anonymous access granted, restrictions apply Remote system type is UNIX. Using binary mode to transfer files. ftp> cd /pub/stage/RYayl7LI 250 CWD command successful ftp> binary 200 Type set to I ftp> get package_27906_130404143929.tar local: package_27906_130404143929.tar remote: package_27906_130404143929.tar 227 Entering Passive Mode (131,142,198,68,223,65). 150 Opening BINARY mode data connection for package_27906_130404143929.tar (84613120 bytes) 226 Transfer complete 84613120 bytes received in 2.57 secs (3.2e+04 Kbytes/sec)
Unpack the tarfile:
unix% tar xvf package_27906_130404143929.tar 1843/oif.fits 1843/primary/acisf01843N003_full_img2.jpg 1843/primary/acisf01843N003_cntr_img2.fits.gz 1843/primary/acisf01843N003_full_img2.fits.gz 1843/primary/acisf01843N003_evt2.fits.gz 1843/primary/pcadf084271087N003_asol1.fits.gz 1843/primary/acisf01843_000N003_bpix1.fits.gz 1843/primary/acisf01843_000N003_fov1.fits.gz 1843/primary/orbitf084197100N001_eph1.fits.gz 1843/primary/acisf01843N003_cntr_img2.jpg 1843/axaff01843N002_VV001_vv2.pdf 1843/secondary/aspect/pcadf084271087N003_aqual1.fits.gz 1843/secondary/aspect/pcadf084265646N003_osol1.fits.gz 1843/secondary/aspect/pcadf084272206N003_osol1.fits.gz 1843/secondary/aspect/pcadf084278602N003_osol1.fits.gz 1843/secondary/ephem/anglesf01843_000N003_eph1.fits.gz 1843/secondary/ephem/lunarf084197100N001_eph1.fits.gz 1843/secondary/ephem/solarf084197100N001_eph1.fits.gz 1843/secondary/acisf01843_000N003_stat1.fits.gz 1843/secondary/acisf01843_000N003_flt1.fits.gz 1843/secondary/acisf01843_000N003_msk1.fits.gz 1843/secondary/acisf01843_000N003_mtl1.fits.gz 1843/secondary/acisf01843_000N003_evt1.fits.gz 1843/secondary/acisf084271178N003_1_bias0.fits.gz 1843/secondary/acisf084271178N003_0_bias0.fits.gz 1843/secondary/acisf084271178N003_2_bias0.fits.gz 1843/secondary/acisf084271178N003_4_bias0.fits.gz 1843/secondary/acisf084271178N003_3_bias0.fits.gz 1843/secondary/acisf084271178N003_5_bias0.fits.gz 1843/secondary/acisf084272477N003_pbk0.fits.gz 1843/secondary/axaff01843N002_VV001_vvref2.pdf.gz unix% ls 1843 package_27906_130404143929.tar
If you downloaded data from multiple ObsIds, a directory will be created for each of them.
The directory looks like:
unix% cd 1843 unix% ls -1 * -r--r--r-- 1 user group 40495 Sep 6 2012 axaff01843N002_VV001_vv2.pdf -r--r--r-- 1 user group 23040 Sep 6 2012 oif.fits primary: total 21808 -r--r--r-- 1 user group 242483 Sep 3 2012 acisf01843N003_cntr_img2.fits.gz -r--r--r-- 1 user group 947669 Sep 3 2012 acisf01843N003_cntr_img2.jpg -r--r--r-- 1 user group 18075861 Sep 3 2012 acisf01843N003_evt2.fits.gz -r--r--r-- 1 user group 82043 Sep 3 2012 acisf01843N003_full_img2.fits.gz -r--r--r-- 1 user group 83881 Sep 3 2012 acisf01843N003_full_img2.jpg -r--r--r-- 1 user group 13679 Sep 3 2012 acisf01843_000N003_bpix1.fits.gz -r--r--r-- 1 user group 5924 Sep 3 2012 acisf01843_000N003_fov1.fits.gz -r--r--r-- 1 user group 287913 Oct 2 2000 orbitf084197100N001_eph1.fits.gz -r--r--r-- 1 user group 2497395 Sep 3 2012 pcadf084271087N003_asol1.fits.gz secondary: total 59272 -r--r--r-- 1 user group 36885019 Sep 3 2012 acisf01843_000N003_evt1.fits.gz -r--r--r-- 1 user group 6949 Sep 3 2012 acisf01843_000N003_flt1.fits.gz -r--r--r-- 1 user group 5467 Sep 3 2012 acisf01843_000N003_msk1.fits.gz -r--r--r-- 1 user group 352300 Sep 3 2012 acisf01843_000N003_mtl1.fits.gz -r--r--r-- 1 user group 297382 Sep 3 2012 acisf01843_000N003_stat1.fits.gz -r--r--r-- 1 user group 436185 Sep 2 2012 acisf084271178N003_0_bias0.fits.gz -r--r--r-- 1 user group 505974 Sep 2 2012 acisf084271178N003_1_bias0.fits.gz -r--r--r-- 1 user group 440218 Sep 2 2012 acisf084271178N003_2_bias0.fits.gz -r--r--r-- 1 user group 433301 Sep 2 2012 acisf084271178N003_3_bias0.fits.gz -r--r--r-- 1 user group 437445 Sep 2 2012 acisf084271178N003_4_bias0.fits.gz -r--r--r-- 1 user group 436956 Sep 2 2012 acisf084271178N003_5_bias0.fits.gz -r--r--r-- 1 user group 4009 Sep 2 2012 acisf084272477N003_pbk0.fits.gz drwxrwxr-x 2 user group 4096 Apr 4 14:49 aspect -r--r--r-- 1 user group 20264414 Sep 6 2012 axaff01843N002_VV001_vvref2.pdf.gz drwxrwxr-x 2 user group 4096 Apr 4 14:49 ephem
The data files are now ready to be used in CIAO. For a description of the files, read the Introduction to the Data Products thread.
History
| 03 Jan 2005 | reviewed for CIAO 3.2: no changes |
| 01 Dec 2005 | reviewed for CIAO 3.3: no changes |
| 01 Dec 2006 | reviewed for CIAO 3.4: no changes |
| 09 Jan 2007 | updated for CIAO 4.0: filenames updated since ObsID 1843 went through Repro III |
| 09 Jun 2008 | updated image display to place figures inline with text |
| 29 Sep 2008 | corrected link for downloading Chaser |
| 30 Dec 2008 | reviewed for CIAO 4.1: no changes |
| 25 Jan 2010 | reviewed for CIAO 4.2: no changes |
| 09 Nov 2010 | the download_chandra_obsid script is a quick and easy method of download data files. |
| 10 Jan 2011 | updated for CIAO 4.3: added more information on using the download_chandra_obsid script |
| 09 Jan 2012 | reviewed for CIAO 4.4: expanded information on using WebChaSeR |
| 16 Feb 2012 | added a section on using the find_chandra_obsid script |
| 03 Dec 2012 | Review for CIAO 4.5; no changes. |
| 04 Apr 2013 | ChaSer is retired. WebChaser now supports individual data product downloads and the ability to upload a list of search criteria. |
