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2.2 Accessing the IUE Archive

 There are primarily three IUE archives. One is located at the National Space Science Data Center (NSSDC) at Goddard Space Flight Center. The other two are in England and Madrid, Spain. The easiest archive to access is the one at NSSDC.

If there are archival images that you would like to work with (see Chapter 2.1 to find out how to look up images in the Merged Observing Log), you may retrieve them from the NSSDC Data Archive and Distribution Service (NDADS) with IUEFX. The calling sequence for IUEFX is

IUEFX,DTYPE,mode=mode,node='node',file='filename',ftype='name' 

where ``DTYPE'' is the data type wanted (see Table 2.2 for examples).

The ``mode'' keyword allows you to specify where the files will be copied to. It may be set equal to a number representing the output destination directory of the data files:

  0    User's current working directory (you will be asked to specify your password). This is the default mode.

  1    Account to be specified by user (the program will need the password for the account given).

  2    Generic account on IUE (you can access the files as IUE::IMAGET).

  3    NDADS staging area (directory syntax is ndadsa::anon_dir:[data_dist.iue]).

If you request to have files copied to an account on a node other than the one you are logged onto, you may specify another node with the ``node'' keyword.

You may also, for IUESIPS data, specify a file format with the ``ftype'' keyword. The available formats are RDAF (the default), GO, and GO-Split (GO format with the VICAR label in a separate file).

If you have a list of camera and image sequence numbers already written in a file, you may submit that list to NDADS with IUEFX using the ``file'' keyword.

Example: If you want to call over the ELBL and MELO files in GO format for LWP 9021 and LWP 9022 into your own account on CHAMP from NDADS, you would type

  IUEFX,'E',mode=0,node='champ',ftype='go'

You would then answer the questions and type in the camera and image sequence numbers of the images you wanted in this format:

  lwp9021 and return

  lwp9022 and return

  hit return again to end

The NDADS system will send you a mail message to let you know whether it found your images or not.

If NDADS is operational, your images may be returned in a few minutes. Lately however hardware problems have resulted in delays of several hours or more. To check on the status of your NDADS job, you may send an e-mail message to archives@ndads.gsfc.nasa.gov or NDADS::ARCHIVES. Type STATUS on the subject line and leave the body of the message blank. You should get a reply that should tell you the status of all the jukeboxes (they will be ``online'' if available or ``offline'' if unavailable). You may see a message about your job in there if your job is currently being executed. Alternatively, you can check the WEB page at:

http://ndads.gsfc.nasa.gov/htadf/ndads_status_www

If the images you requested do not appear in your account and NDADS sends you a mail message that says that it ``failed to copy'' your files, but that they may already exist in the staging area, you can look for them in the staging area and copy them yourself (note the leading zero in the image sequence number):

  dir ndadsa::anon_dir:[data_dist.iue]lwp09021*.*

  copy ndadsa::anon_dir:[data_dist.iue]lwp09021slg.* *.*

  copy ndadsa::anon_dir:[data_dist.iue]lwp09021LLG.* *.*

INTERNET users can get files from the staging area via anonymous FTP. Files must be transferred in binary mode. The TCP/IP address for NDADSA is 128.183.36.17.

Note that IUE data is no longer subject to any proprietary period. All data is available to the public as soon as it is archived. This applies to both IUESIPS and NEWSIPS data sets.

 

 
Table 2.1: IUEFX Data Types
DTYPE Files Retrieved
ALLF NEWSIPS ri, li, si, mx files
ALLI IUESIPS raw, PI, LBL, melo, mehi
ELBL1 IUESIPS lbl files (large ap.)
ELBL2 IUESIPS lbl files (small ap.)
EXTF NEWSIPS si, mx files
EXTI IUESIPS lbl, me files
IMAGE IUESIPS raw, PI files
LI NEWSIPS li files
LIHI NEWSIPS lihi files (high disp.)
LILO NEWSIPS lilo files
MEHI IUESIPS mehi files
MEHI1 IUESIPS mehi files (large ap.)
MELO IUESIPS melo files
MELO1 IUESIPS melo files (large ap.)
MELO2 IUESIPS melo files (small ap.)
MX NEWSIPS mx files
MXHI NEWSIPS mxhi files (high disp.)
MXLO NEWSIPS mxlo files
PI IUESIPS pi files
RAW IUESIPS raw files
RI NEWSIPS ri files
RIHI NEWSIPS rihi files (high disp.)
RILO NEWSIPS rilo files
SI NEWSIPS si files
SIHI NEWSIPS sihi files (high disp.)
SILO NEWSIPS silo files
SPECTRA IUESIPS lbl and/or merged files


next up previous contents
Next: 2.3 Transferring Data Files Up: 2 REQUESTING DATA Previous: 2.1 The IUE Merged

2/9/1998