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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

Sebastian Otero
Affiliation
American Association of Variable Star Observers (AAVSO)
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

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