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514Re: [vsx-dis] How and when to submit data to VSX.

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  • Sebasti├ín Otero
    Nov 2, 2012
      Hi, Tomas,

      > I'm an amateur astronomer from Sweden and a member of AAVSO (WTHB). I have
      > recently, due to the very poor Swedish autumn weather, done some variable
      > search in my pictures gathered with iTelescope. I have been using vphot
      > and VS search.
      > When examining my pictures I found a suspected variable star, close to
      > v393 Her, in position RA 17:22:40.06 DEC+26:55:23.64. After checking NSVS
      > and ASAS, I found out that this star seems to be variable, but has no
      > entry in VSX. It's known as NSVS 7991812 and ASAS 172239+26551.
      > Because I'm monitoring v393 Her, I would also like to have this star
      > entered in VSX to be able to load sequences in vphot and report the
      > magnitudes to AAVSO.
      > I have read the instructions in VSX, but I honestly don't know how to do
      > in this particular case. Should I try submitting and hope that the VSX
      > crew can guide me if it looks awkward?

      Please, be more specific regarding what you don't understand in the VSX

      From what you say it seems that the variability is apparent in NSVS and
      ASAS-3 data so the natural approach would be combining your observations
      with those from those surveys. This will surely allow to classify and find
      the elements for the variable star in question.

      Are you working with filters or unfiltered?

      The difference between filtered and unfiltered data depends on the star's
      color. If it is not a red variable shifting all magnitudes to the V scale
      (of your observations or ASAS-3) would work.

      So, combine the datasets, make a period search, classify the star based on
      the light curve shape, determine an Epoch (a time of primary minimum for
      eclipsing binaries, dark-spotted or RV Tauri stars and a time of maximum for
      pulsating variables and hot-spotted stars), make a phase plot (with
      different symbols for each dataset and showing 1.5 or 2 variability cycles
      for clarity and with your Epoch as phase 0) and submit the star to VSX.

      Fill in the form with as much information as possible.

      Give a catalogue name to your star (HD, BD, SAO, GSC, 2MASS, in that order)
      as well as other names from astrometric catalogues or surveys (UCAC4, NSVS,

      Use UCAC4 for the position.

      Use the variability types dropdown menu to choose the relevant type.

      Give the range and the passband. Choose V since you have ASAS-3 data (what
      magnitude are we talking about?)
      For the range, if the star is strictly periodic, give mean values for the
      maximum and minimum magnitudes, not extreme values. Take scatter into

      Add the elements you determined.

      Add the rise duration value if it is a cepheid, RR Lyrae or HADS (the time
      between a time of minimum and a time of maximum expressed as a percentage of
      the period)
      Add the eclipse duration (the same field) if the star is an EA-type
      eclipser. It is the time since the primary minimum's first contact (start of
      the descending branch) to the last one (end of the ascending branch)
      expressed as a percentage of the period. E.g. if the eclipse starts at phase
      0.95 and ends at phase 0.05 the eclipse duration will be 10.

      In the additional remarks field you can add other information that couldn't
      be entered into the other fields. E.g.: magnitude of min II, the phase when
      min II happens if it is an eccentric binary, the presence of the O'Connell
      effect if maxima are different, other periods in case of multiperiodic
      stars, etc.

      Any doubt you can ask here, or as you have mentioned yourself, you can
      submit your star and then we'll guide you through the changes you need to
      But I think we have all more or less covered now.

      Do you have a possible classification for your star?

      Best wishes,

      Sebastian Otero
      VSX Team
      American Association of Variable Star Observers
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