Does that mean that I have also phantom over line inputs? Is that even possible? In case i'ts right and it's possible...in that case I just have to buy a "minijack stereo to 2 jack mono", haven't?
I took a quick look at the manual and its specs (pg 114) suggest the unit provides phantom power over both XLR and 1/4". However, whether you use the XLR or 1/4" connectors probably doesn't matter (though I recommend XLR since I find them more secure):
Since your AT853s are terminated in an 1/8" stereo plug, this suggests the mics do not include a phantom power adapter, but instead are configured to run on plug-in power. Therefore, you need an adapter cable that does two things: <1> converts the connectors, i.e. XLR to 1/8", and <2> converts phantom power to plug-in power. Naiant's PFAs will accomplish both.
Warning: connecting your plug-in power mics directly to a phantom power source may damage your mics.