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IUE Data Issues

DougBurke edited this page Jun 16, 2011 · 11 revisions

IUE Data Issues

1 - Missing data

At present the obscore table only contains low-resolution data for IUE. A quote from Karen:

You have it exactly right. Since the high-dispersion IUE data are echelon and that has not been addressed yet by the spectral model / SSAP we never put them in to the vo format and the Obscore table and I'd totally forgotten that aspect of things. Let me talk with Randy and see what we can do about it.

Karen

###Example

An example of this is the source HD 39801 which has, amongst many observations, high-res data for LWP00501 and LWP31662 that are missing from obscore.

2 - Target names

A look at some of the target names returns values like:

#24(N5139), #39(NGC4449), #5701(N5139), & AND, & CEP, & LEP, 0

Matching against the archive I've worked out that '& CEP' is 'S SEP' and '& AND' is 'LAMBDA AND', '& LEP' is 'LAM LEP'.

The '#x(NGCy)' versions do match the archive!

There are also a bunch (568) that have a name of "0" and look like

A  B             C                    D  E  F  G
0  lwp03438mxlo  1984-05-26 04:32:00  0  0  0  0
0  lwp03439mxlo  1984-05-26 04:55:00  0  0  0  0
0  lwp03495mxlo  1984-06-04 22:52:00  204.25035010299999  -29.865136948499998  204.25035010299999  -29.865136948499998
0  lwp03597mxlo  1984-06-15 23:00:00  0  0  0  0
0  lwp03603mxlo  1984-06-17 02:36:00  0  0  0  0
0  lwp03759mxlo  1984-07-14 02:30:39  327.79180331139997  28.861237019499999  327.79180331139997  28.861237019499999

where A is the target_name, B the obs_id, C the date_obs and D/E/F/G the s_ra s_dec ra_targ dec_targ columns.

Response from Randy:

Thanks for the feedback. This table has not received much testing yet. I'll look into these problems tomorrow. I suspect this is an error caused during incorrect global updates. I found 8 rows with '&' in the target name.

I suspect the 0 entries are calibration exposures and should be removed. The few I tried do not appear in our normal IUE search interface.

Note: the MAST team have obviously done some curation on target names since they have separate columns for 'GO Object Name' and 'Target name'. Follow the links to find out what they did.

3 - obs_id values

The obs_id column in the obscore table has the form 'swp58388mxlo' (presumably, when the high-res data gets added we will see 'xxxmxhi' versions as well), whereas the bibliographic mapping uses just the first 8 characters; e.g.

BIBCODE DSN     PROGRAM
1978A&A....70L..53S     LWR01933        VILSP
1978A&A....70L..53S     LWR01933        VILSP
1978A&A....70L..53S     SWP02092        UKFIL
1978A&A....70L..57S     SWP01721        KH001
1978A&A....70L..57S     SWP01721        KH001
1978A&A....70L..57S     SWP01737        KH001
1978ApJ...226L..57B     SWP02148        UK016
1978Natur.275..377B     LWP01031        RCB

This is simple to handle but needs to be recognized.