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Phases range

Degen1103
Affiliation
American Association of Variable Star Observers (AAVSO)
Mon, 03/27/2023 - 09:28

It is written in VSX FAQ:

  • Display phase 0 to 2 in the case of pulsating variables so the maximum is displayed in the middle.
  • Display phases -0.25 to 1.25 (or -0.5 to 1.5) in the case of eclipsing binaries so the secondary eclipse is displayed in the middle.

Is it possible to display noted phases in VStar plots? I treid to change Domain axis range limits in Properties, but it does not affect on phase curve range -1...+1.

David__Benn
Affiliation
Astronomical Society of South Australia (ASSAU)
Mon, 03/27/2023 - 12:37
Phase range

VStar plots the so-called standard phase (0..1) and the previous cycle phase (-1..0).

You can certainly zoom into the phase plot (via bounding box or View -> Zoom In/Out) so that -0.25 to 1 is prominent and the epoch can be set appropriately, e.g. so that phase zero is at the minimum of the primary eclipse.

Phase plots in Fig 11 of https://authors.library.caltech.edu/13280/1/DEVaj08.pdf show this kind of thing but the range seems to be closer to -0.25 to 0.75.

Can someone explain the need for -0.25 to 1.25 (or -0.5 to 1.5)?

David

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Sebastian__Otero
Mon, 03/27/2023 - 13:50
Eclipsing binary phase plots

Hi David,

it is a suggestion not a requirement, but it is much easier to see the light curve shape of the eclipses when they are shown in the middle of the plot. -0.25 to 1.25 allows you to see both eclipses clearly. Other variants, like the classical 0 to 2, are okay, but having the two full cycles displayed will compress the light curve and, for narrow eclipses, detail will be lost.
That's all.

Cheers,
Sebastian

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David__Benn
Affiliation
Astronomical Society of South Australia (ASSAU)
Mon, 03/27/2023 - 22:51
Captured

Hi Sebastian

Thanks for the explanation. I've captured the issue here: https://github.com/AAVSO/VStar/issues/343

David

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mpyat2
Affiliation
American Association of Variable Star Observers (AAVSO)
Wed, 03/29/2023 - 07:52
Phase range
  • Display phase 0 to 2 in the case of pulsating variables so the maximum is displayed in the middle.

Actually, the existing default range -1 to 1 is equivalent to the 0 to 2 range. What to choose is a matter of taste (tradition).

However, if the VSX manual recommends it, it would be good to make a possibility in the VStar to make 0..2 as an option.

I think, it could be a menu item with a selection submenu (it's faster for the user to select) or/and a section in the "Preferences".

Say, 

View ->

   Phase range ->

  • -1 to 1
  • -0.5 to 0.5
  • -0.5 to 1.5
  • -0.25 to 1.25
  • 0 to 1
  • 0 to 2
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