WRs in the Magellanic Clouds--Redux!

• Swope e2v
  • 4096x4110
  • 0.435"/pixel
  • 29.7' NS x 22.8' (EW)
  • Recommended maximum counts: 50,000 (Carlos)
  • Measured gain and rdnoise last year:
    • c1: 1.06, 3.1
    • c2: 1.05, 3.6
    • c3: 1.00, 3.4
    • c4: 1.03, 3.2

LMC

• Fields
  • Center: 5:18:00 -68:45:00 Radius = 210' (diameter 7.0 deg)
  • Area: 38.5 deg^2 = 450 fields.
    • Circle coverage based upon known WRs and light distribution
    • Field shown with Halpha emission. WCS isn't perfect.
    • List of LMC fields
    • Images and Region files (do it yourself in ds9):
      • LMC R image
      • LMC H-alpha image
      • lmcwr.reg (including new ones)
      • lmccirc.reg
      • lmce2vfields.reg Our 354 e2v fields
      • Site3cents.reg (2013 fields done)
• List of all known WRs
• Kathryn's list of priorities.
  • The above file contains the number of WR stars, the number of blue and red stars, and the number of Lucke-Hodge OB associations in a given field. For the blue and red stars we used UCAC3 with the following restrictions:
    • Center 5:18:00 -68:45:00 radius=4.0deg (larger than our field area)
    • ot>=0 && <=2
    • db 0
    • pmRA>-15 && < 15
    • e_pmRA>0
    • pmDEC>-15 && < 15
    • e_pmDEC>0
    • q_J 5
    • q_K 5
    • Our program than selected stars with J-K < 0 and 11 < K < 15 as blue stars, and 0.9 < J-K < 1.4 K ≤ 10.2 as red stars.

SMC

• Fields
  • Center: 1:08:00 -73:10:00 Radius = 180' (diameter 6.0 deg)
  • Area: 28.5 deg^2 = 330 fields.
    • Circle coverage based upon known WRs and light distribution
    • Field shown with Halpha emission. WCS isn't perfect.
    • List of SMC fields
    • List of LMC fields
    • Images and region files (do it yourself in ds9):
      • SMC R image < /a>
      • SMC H-alpha image
      • smcwr.reg. All the WRs.
      • smccirc.reg. The 6 deg dia circle
      • duf.reg. All of the previous surveyed fields.
      • smce2fields.reg Our 242 e2v fields.
• List of all known WRs .
• Kathryn's list of priorities.
  • The above file contains the number of WR stars, the number of blue and red stars, and the number of Lucke-Hodge OB associations in a given field. For the blue and red stars we used UCAC3 with the following restrictions:
    • Center 1:08:00 -73:10:00 radius=3.5deg (larger than our field area)
    • ot&ge 0 && &le2
    • db 0
    • pmRA > -15 && < 15
    • e_pmRA>0
    • pmDEC > -15 && < 15
    • e_pmDEC > 0
    • q_J 5
    • q_K 5
    • Our program than selected stars with J-K < 0 and 11 < K<15 as blue stars, and 0.9 < J-K < 1.4 K ≤ 10.2 as red stars.

E2V Calibration Procedure

• Shutter correction frames: In V: 3x20sec, 20x1sec, 3x20sec, 10x2sec. The 2sec are there as a check. The extra time that the shutter is open (can be negative) is F(x,y). If you divide the two, you have (1+F(x,y))/(20+F(x,y)). Given that F(x,y) is of order 0.05, you can ignore it on the bottom, and you are left with image1/image20 = F(x,y)/20 + 1/20. Then F(x,y) = (20 x image1/image20) - 1. Construct 1Fxy=1+F(x,y), 2Fxy=2+F(x,y), 3Fxy=3+F(x,y), ...15Fxy=15+f(x,y), and use these to divide into twilight flats.
• Note: You get about 1300e for a 1 sec exposure. So, 20 of them gives you a S/N of 160, or 0.006 mag error. But if you want a S/N of 1000 (0.001 mag) you'll need 750 of them! I compromised with 300 (macro: Shut15.txt) for S/N of 625 (0.0016 mag).

• 10 bias frames
• Dome flats are 3x600 sec but 10% gradient up and down.
• Sky flats: Can do 1-15 seconds. Try to get 5 in each filter, offsetting by 30" N, say.

Observing Procedures

• TCS:
  • To stop a bad slew just hit the "ESC" key. BUT THEN DO A "DOME AUTO".
  • Always check the time at the start of the night against http://www.time.gov. To update TCS do a UT hh mm ss.
  • Good cset stars:
    • SMC: 01:05:07.94 -71:44:02.2 [8.0]
    • LMC: 04:51:20.77 -68:04:10.8 [7.7]
• CCD System:
  • To reboot Puma:
    • Exit from Swope [the CCD system] and all IRAF tasks.
    • Restart. Log in as "obs1" with the password above the desk.
    • Click on Swope to restart the ccd system.
    • Click on IRAF to start up IRAF and launch ds9.
• Guider:
  • DSPI (reinitializes things)
  • TEC 1.5 [turns the cooling on]
  • SPAN 10000 if bright, 500 if faint
  • Can change the box size depending on the seeing by doing a 'bx 19', say. Has to be an odd number.
• Focusing:
  • Good focus for V filter is 23.750-24.000. Focus steps of 0.050
  • The offset for the WR filters is probably -0.100 wrt to V, so you can, in principle, focus in V. Use 10 sec exposures and step sizes of 0.050. If the temperature goes down, the focus goes down. IS THIS TRUE?
• Retrieving data:
  • cd /volumes/jenny on your laptop
  • rsync -azv obs1@puma.lco.cl:/volumes/DATA_SWOPE/ut171204_05 .
  • Log in on white board or look up email from George on Dec 2, 2017.

Basic Reductions

• Complete details are given at our E2V reductions web page
• Load imred, ccdred, and do a "setinstrument" direct
• Run e2v
• More likely you'll want to hand-construct your own master flat (corrected for shutter corrections) from the sky. Using e2vnoflat is useful.

Analysis Pipeline

• Basic CCD reductions (see above)
• Move the SMC/LMC frames to a subdirectory "photom". Manually eliminate any non-interesting frames (such as biases) or repeated observations you don't want.
• Load digiphot/daophot and obsutil.
• alle2v does the following:
  • autoe2v: will produce photometry of all of the stars. Output: ccdxxxxSUM
  • hselect *f.fits $I,filter,title IMAGETYP=='OBJECT' > flist
  • autosetup: creates a file with the image and field names. Output: fields
  • findem3: takes the photometry of all of the stars and picks out WRs. Also writes iraf script to shift the images. Outputs: SMCexxxa.WR, shifts, and fort.4
  • cl < shifts to create images aligned with CT. Outputs: SMCexxxWCa.fits and astromimages
  • astronet3 sets things up to run solve-field. Output: astrom
  • source astrom to run solve-field. Output: SMCexxxWCat1.fits
  • cl < fort.4 (left over from findem3) to now put RAs and Decs in the the photometry files. Output: SMCexxxRA.WR and SMCexxxsum.RA
  • cp *t1.fits /users/massey/dropbox/SwopeIII/NOV15 and a cp *RA.WR /users/massey/dropbox/SwopeIII/NOV15.
• Now we do all of the "quality control" operations:
  • hselect *t1.fits $I,exptime yes >> /users/massey/dropbox/SwopeIII/NOV15/exptimes
  • qualu runs the "quality assurance check" against UCAC4 APAS B magnitudes (11..17). Alternative "qual" uses Zaritsky's MC survey, selecting stars that are brighter than B=17th and with Berrors < 0.15 mag. Output gets appended to dropbox/SwopeIII/NOV15/photsum.
  • When all of the various subdirectories are processed, we add the relative changes in the fwhm and the quality of the photometry (corrected for the fwhm) to the headers in NOV15:
    • cd /users/massey/dropbox/SwopeIII/NOV15
    • addphot [takes photsum and creates fort.3 that will stick "photq" in the headers
    • cl < fort.3
    • hselect *t1.fits $I,fwhm,photq yes > fwhmphot.dat You can make fun plots of the fwhm (column 3) with the photometric zero-point (column 2) using old data for comparision. Basically values above 5 for the photometric zeropoint are bad, unless the seeing is awful.
    • addhead
    • cl < fort.3
    • hselect *t1.fits $I,fwhm,photd,fwdelt yes > HowGood.txt This will show the percentage change in the fwhm relative to the continuum. Anything over 10% is pretty bad.
  • There's one more thing we need to check: where WERE we pointing?
    • cd /users/massey/dropbox/SwopeIII/NOV15
    • files *CTt1.fits > allcts
    • create file 'e2vxyc' which contains 2055 2048
    • wcsctran e2vxyc STDOUT @allcts logical world format=%12.3H 12.2h verbose=no > rds
    • join allcts rds > e2vCentsNov15.txt
    • Add this to /users/massey/dropbox/SwopeIII/e2vcent.txt
    • Run mke2vreg to make .reg file and cp fort.12 to e2verror.txt and fort.3 e2vobserved.reg

  HOTPANTS

  After the images were aligned the command that finally worked in terms of making a nice resultant image was:

  • OLD: hotpants -inim WNframet1.fits -tmplim CTframet1.fits -outim Result.fits -tu 60000 -c t -n i -ng 7 2 0.5 2 0.75 2 1 2 1.125 2 1.5 2 1.75 2 2.0 -tl -30 -tg 3 -tr 7 -iu 60000 -il -30 -ig 3 -ir 7
  • NEW: hotpants -inim WNframet1.fits -tmplim CTframet1.fits -outim Result.fits -tu 60000 -c t -n i -ng 5 3 1 3 1.5 3 2 3 2.5 3 3 -tl -30 -tg 5 -tr 6 -iu 60000 -il -30 -ig 5 -ir 6