Kepler related question

[Basilisk]

Hi, this is my first post, and it is sort of a complicated question (I think. Perhaps it is easy and I don't know how to solve it).

In the Kepler catalog, are there any binary star systems, where the secondary star orbits the central star that have something close to the following conditions?.

- Can't be like Alpha Centauri where A and B are orbiting around a mass center. I need the secondary star to have a fixed orbit around the primary star (doesn't have to be circular, can be elliptical, the lower the eccentricity the better, though)

- Enough orbital space between the central star and the secondary star orbits to have a habitable zone around the primary star.

- Stars are G and K classes combination (like Alpha Centauri), so there is no photon-cannon around to make carbon based life impossible (no O stars in the vicinity).

- The closest to our Sol system, the better.

Any help will be appreciated.

Also, if there is any good Kepler resource that you guys can point me to, like an online database or such where I can get this information by myself, that would be awesome.

Thanks in advance and sorry for my newbism.

[Basilisk]

Let me update this. I found that binary stars systems with one star orbiting another are very rare, if not impossible.

So, let me change my question to another kind of star system. I need a triple star system with a habitable zone around the central binary pair, with a third heavier, larger and brighter star orbiting around the central binary pair. Basically, like this:

Thanks again for any tips on the sun's closest stellar system with that setup.

[Qualia]

I need a triple star system with a habitable zone around the central binary pair, with a third heavier, larger and brighter star orbiting around the central binary pair.

Can't help with the particulars, but these records of triple systems, might offer fruitful promise to your enquiry.

[Capricorn]

Initial question is not possible, any 2 stars will orbit around a centre of mass.

Even the planets and the sun orbit around a centre of mass, that is not the centre of the sun. Because the planets are small the centre of mass may be inside the sphere of the sun but it will not be the centre of it. That is how exoplanets are detedced byt the subtle wobble of the sun they orbit.

A triple system operates the same, just more complex as all 3 stars are orbiting a centre of mass that is defined by the relative positions of the stars.

In your diagram of a triple system the centre of mass will probably be right where you have a band marked Habitable Zone.

What in simple terms would happen is that the 2 central binary star would orbit around a local centre of mass and this centre would orbit around the real centre of mass crearted by all 3.

Depending on each star mass and the seperation there may be stable zones around each star that a planet could exist. However whether or not a habitable zone would exist is more questionable. Each star would need to be well seperated from it's neighbour and each star would need to be stabe