What happens to your data after CCDPROC and PHOT

This entire page is hands-off for the students. ACL will take care of organizing everyone's *.txd files into one place. I include this description (i) so students understand how the data flows through this step, and (ii) so ACL has a convenient cookbook to follow, to ensure he does everything consistently.

1) After a student has finished PHOTing a night of data, there should be a set of *.txd (TXDUMP) files in that directory. Each .txd file contains the magnitudes (instrumental, not yet transformed to standard V or I magnitudes) of the variable star and several comparison stars measured from a specific image. It also includes the HJD, airmass, and other information that will be needed for making light curves.

For example, maybe Jane Schmoe just finished PHOTing data in the directory

da> pwd
da> ls *.txd
RU_Lup1i1.txd   U__Pic1i1.txd   RV_Sex1i1.txd
RU_Lup1i2.txd   U__Pic1i3.txd   RV_Sex1i2.txd
RU_Lup1i3.txd   U__Pic1i3.txd   RV_Sex1i3.txd   (...etc)


2) ACL will move Jane's .txd files to a common place where they will be combined with data from other nights. We will put all the data for a given star (e.g., RU Lupi) into a directory all by itself (e.g., /data/layden/BGTEL/ALL/RU_Lup).

As they are copied over, the individual *.txd files must be renamed. That is because the directory for each star (e.g., RU Lupi) has (or will have) many nights of data in it, and on each night, there may be a file called RU_Lup1v1.txd (etc). If we gave them all the same name, the existing files would get overwritten and the data lost. To keep them straight, their new name will include the date on which they were taken, as well as the "2v3" (visit/filter/exposure-number) extension: eg, "01aug131i2.txd". The starname information is now "kept" because each directory (eg /data/layden/BGTEL/ALL/RU_Lup) contains only data from a single star.

The script called cp_txd.cl will rename the file automatically, but it requires that certain naming conventions be strictly adhered to, lest data get overwritten!


3) Before you do any copying, you need to be sure the destination directories are there. If it is not, you must create them. Begin by checking which stars were observed on the night in question:

da> ls *v1.txd     (or *i1.imh if your images are I-only)

Then see if all the directories are there in the destination:

da> cd /data/layden/BGTEL/ALL
da> ls
U__Pic     (the directory for U Pictoris exists)
      RV_Sex     (as does a directory for RV Sextansis)

However, there is no directory for RU Lupi, so make one. It must have the same 6 letters as the first 6 letters in the starname (capitals matter!).

da> mkdir RU_Lup


4) Keep a record of all data copied to /data/layden/BGTEL/ALL, including brief notes on quality:

da> emacs OBS_NOTES/notes.doc &


5) Copy the *.txd files from Jane's directory to the current one (/data/layden/BGTEL/ALL):

da> cp /data/jshmoe/PHOT/01aug13/*.txd .


6) Run the script called cp_txd.cl to copy the *.txd files from the current directory into the appropriate subdirectories (unique to each star). The program will ask you for the "date ...". In our example, you would respond with the date 01aug13. Note that the date must contain 7 characters, and be in the YYmmmDD format! Students: don't try this!

da> cl < cp_txd.cl 
   Enter date for new filename root (7 chars, eg, 99jul07):  01aug13
            24 TXDUMP files prepared for writing


7) Check to see that the files were copied. Notice that the first 6 letters of the filename (which used to indicate which star had been observed) are now replaced with the 7 letters indicating the date. If there are other observations from other nights in the directory (e.g., U__Pic/99may281v1.txd), it will have a different name. The 1v1, 2i3, etc still uniquely identifies the different images taken of a star on a given night. Notice how strict adherence to the file nameing convention is important to keeping things straight, and avoiding overwriting (and thus losing!) exising data.

da> ls /data/layden/BGTEL/ALL/RU_Lup
01aug131i1.txd  (...etc)
da> ls /data/layden/BGTEL/ALL/U__Pic
99jun031i1.txd       01aug131i1.txd  (...etc)


8) If there were any errors when you ran the script, you will have to correct them and rerun the script. A "cannot create file" error probably means you did not create a directory for the files to be copied into (or that the directory name and star names do not match exactly).


7) In the original student directory, there should be a file "reduce.doc" (or equivalent) that gives details about the observations, reductions, and photing. Be sure to copy the relevant info (especially caveats) into notes.doc file. If the comments in reduce.doc are extensive, you might copy the whole thing into OBS_NOTES (name it by the date, eg)

da> cp /data/jshmoe/PHOT/01aug13/reduce.doc OBS_NOTES/01aug13.notes


8) Update paper log of nightly reductions in blue folder. Should be processed/taped through ALL.


Updated 2001 Jun 20 -- ACL