Reference files used by the COS calibration pipeline (CALCOS)) are updated on a regular basis. Current reference files files can be retrieved from the HST archive, or downloaded directly from the lref directory. Note that FTP access is browser dependent: Safari does not work; Firefox or Chrome may or may not work depending on the Operating System. If you cannot download the files via Firefox or Chrome, you can try using a standalone FTP tool or accessing the ftp site directly (ftp ftp.stsci.edu) with 'anonymous' (without quotes) as your username and your email address as your password.
If you would like to receive an e-mail every time a new COS reference file is delivered and the database is updated, you can subscribe
to the cos_reffiles_upd mailing list. To subscribe to this list, send an e-mail to MajorDomo @ stsci.edu with the following in the body
of the message:
subscribe cos_reffiles_upd your_address .
New tools for exploring COS Reference Files are now available at https:/hst-crds.stsci.edu. To get a listing of the reference files you're interested in, click on 'cos' then select the filetype. Use the names below in the Header Keyword column as a guide.
| Reference File Type | Extension | Header Keyword | Detector |
|---|---|---|---|
| Flat Field Files Accounts for pixel-to-pixel variations. More... |
flat | FLATFILE | Both |
| Geometric Distortion Correction Images Corrects for the intrinsic nonlinearity (INL) of the FUV detector. More... |
geo | GEOFILE | FUV |
| Bad Time Interval Table Lists the start and end times of known bad time intervals. More... |
badt | BADTTAB | FUV |
| Baseline Reference Frame Table Used when applying the thermal distortion correction. More... |
brf | BRFTAB | FUV |
| Burst Parameters Table Provides the parameters needed for deciding when the count rate in some time interval in FUV time-tag data is too high to be regarded as normal. More... |
burst | BRSTTAB | FUV |
| 1-D Extraction Parameters Table Gives the location of the spectrum to be extracted from a 2-D image. More... |
1dx | XTRACTAB | Both |
| Bad Pixel Table Gives the locations of rectangular regions that cover portions of the detector that are known to be less than optimal. More... |
bpix | BPIXTAB | Both |
| Deadtime Reference Table Used to obtain the true number of events received compared to the number of events counted by the detector electronics. More... |
dead | DEADTAB | Both |
| Dispersion Coefficients Table Gives a set of polynomial coefficients for computing wavelength from pixel number. More... |
disp | DISPTAB | Both |
| Calibration Lamp Spectra Table Used to determine the pixel offset of the observed data. More... |
lamp | LAMPTAB | Both |
| Pulse Height Parameters Table Lists the lower and upper thresholds for valid individual pulse heights in TIME-TAG mode as well as the minimum and maximum values for the location of the mean value of the pulse height distribution used in ACCUM mode. More... |
pha | PHATAB | FUV |
| Photometric Sensitivity Reference Table Provides the information needed to convert from corrected detector counts to flux units. More... |
phot | FLUXTAB | Both |
| Spectroscopic WCS Parameters Table The spectroscopic WCS parameters table gives values to be used for populating the world coordinate keywords. More... |
SPWCS | SPWCSTAB | Both |
| Time Dependent Sensitivity Table Gives information about the relative sensitivity as a function of time and wavelength. More... |
tds | TDSTAB | Both |
| Wavecal Parameters Table Gives information about the relative sensitivity as a function of time and wavelength. More... |
wcp | WCPTAB | Both |
| High Voltage Reference Table The high voltage reference table gives the times when the FUV high voltage was changed More... |
hv | HVTAB | FUV |
| Walk Correction Reference Table The walk corection reference table gives parameters for correcting the pixel coordinates XCORR and YCORR of FUV TIME-TAG data More... |
walk | WALKTAB | FUV |
| Gain Sag Reference Table The gain sag reference table gives the locations of rectangular regions for portions of the FUV detector that have very low pulse height amplitude (PHA). More... |
gsag | GSAGTAB | FUV |