Widespread galactic CF+ absorption: detection toward W49 with the Plateau de Bure Interferometer H. S. Liszt, V. V. Guzmán, J. Pety, M. Gerin, D. A. Neufeld and P. Gratier A&A, 579 (2015) A12 Published online: 19 June 2015 DOI: 10.1051/0004-6361/201526232