{
  TChain *chain1 = new TChain("Tree1");
  chain1->Add("inputfile1.root");
  TChain *chain2 = new TChain("Tree2");
  chain2->Add("inputfile2.root");

  chain1->AddFriend(chain2);
  chain1->SetBranchStatus("*",0);

  chain1->SetBranchStatus("Tree2.d",1);
  chain1->SetBranchStatus("a",1);
  chain1->SetBranchStatus("b",1);

  TCut myTCut="a>1.";
  
  TTree *newTree = chain1->CopyTree(myTCut);
  TFile *fout = new TFile("outputfile.root","recreate");
  fout->WriteTObject(newTree);
  fout->Close();

}