It looks like it doesn't have any gas giant planets.
The remnants of a star like the Sun after it goes all red can be seen in the form of a white dwarf. The Sun is packed into a ball about the same size as Earth.
The path takes the stars from 1.2 to 4.5 billion kilometers apart each 50 years. They are one of the closest stars to us in the universe.
Since the primary has twice the mass of the Sun, no planet would be able to stay in the same place for more than 1.5 times the Earth's distance. The gravity of the primary will throw anything further out.
There is a chance that planets are closer in than the limit. The team of astronomer used a 10-meter telescope in Hawai'i to take several observations of the dead star in 2020. It is difficult to think of a way to make this happen given the bright Sirius A is just a few seconds away. They got a number of good observations.
In order to look for planets, they took two images at the same time, center the image of the star as accurately as possible, and then subtract the second image from the first. The star will disappear if this is done right. A bright dot next to a dark spot in the image is caused by the rotation of the image moving the planet in the picture.
It is more complicated than this, and there are many ways to implement it, like rolling the telescope into a different altitude to see two images of a star.
They were able to show that any planet more massive than 1.6 times that of Jupiter would be visible in their data out to about 75 million kilometers from the star.
There are no planets bigger than those limits at those distances. Smaller ones could be there. It might be possible.
White dwarfs are able to have planets. A couple of years ago the white dwarf was found to have a Jupiter-sized planet circling it, which means it is bigger than the host star. We know it's possible.
There is more evidence that they can host planets before they turn into white dwarfs. You can argue that the first evidence of an exoplanet was in a spectrum of a white dwarf taken in 1917, because we have lots of observations of white dwarfs where the inner planets were torn apart. Calcium, iron, and magnesium are elements that should sink quickly into the star's fluid interior. There isn't enough time for them to sink because the star tore apart and ate a rocky planet. It's really cool.
There is no evidence of this happening with the other one. When it became a red giant millions of years ago, it probably consumed any planet less than 230 million kilometers out, so maybe we shouldn't expect to find planets around it. It is true that some planets can survive their host star's red giant phase, but they would have to be a long way out.
Nature is smarter than we are and may know a way to spare planets that fate. It is a good idea to check. We won't find surprises if we don't look.
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