The CARMENES search for exoplanets around M dwarfs: Detection of a mini-Neptune around LSPM J2116+0234 and confirmation of a super-Earth around GJ 686 (BD+18 3421)

L.S. acknowledges support from the Deutsche Forschungsgemeinschaft under DFG DR 281/32-1. CARMENES is an instrument for the Centro Astronomico Hispano-Aleman de Calar Alto (CAHA, Almeria, Spain). CARMENES is funded by the German Max-Planck-Gesellschaft (MPG), the Spanish Consejo Superior de Investigaciones Cientificas (CSIC), the European Union through FEDER/ERF FICTS-2011-02 funds, and the members of the CARMENES Consortium (Max-Planck-Institut fur Astronomie, Instituto de Astrofisica de Andalucia, Landessternwarte Konigstuhl, Institut de Ciencies de l'Espai, Insitut fur Astrophysik Gottingen, Universidad Complutense de Madrid, Thuringer Landessternwarte Tautenburg, Instituto de Astrofisica de Canarias, Hamburger Sternwarte, Centro de Astrobiologia and Centro Astronomico Hispano-Aleman), with additional contributions by the Spanish Ministry of Economy, the German Science Foundation through the Major Research Instrumentation Programme and DFG Research Unit FOR2544 >Blue Planets around Red Stars>, the Klaus Tschira Stiftung, the states of Baden-Wurttemberg and Niedersachsen, and by the Junta de Andalucia. Data were partly obtained with the MONET/South telescope of the MOnitoring NEtwork of Telescopes, funded by the Alfried Krupp von Bohlen und Halbach Foundation, Essen, and operated by the Georg-August-Universitat Gottingen, the McDonald Observatory of the University of Texas at Austin, and the South African Astronomical Observatory. Data were partly collected with the 90 cm telescope at Sierra Nevada Observatory (SNO) operated by the Instituto de Astrofifica de Andalucia (IAA). We acknowledge financial support from the Spanish Ministry for Science, Innovation and Universities (MCIU) AYA2015-69350-C3-2-P, ESP2016-80435-C2-1-R, ESP2016-80435-C2-2-R, AYA2016-79425-C3-1/2/3-P, ESP2017-87676-C05-02-R, ESP2017-87143-R, BES-2017-082610, SEV-2015-0548-17-2, Generalitat de Catalunya/CERCA programme; Agencia de Gestio d'Ajuts Universitaris i de Recerca of the Generalitat de Catalunya through grant 2018FI_B_00188, and the Israel Science Foundation through grant 848/16. This work makes use of data from the HARPS-N Project, a collaboration between the Astronomical Observatory of the Geneva University (lead), the CfA in Cambridge, the Universities of St. Andrews and Edinburgh, the Queens University of Belfast, and the TNG-INAF Observatory; from observations obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation; from observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programmes 183.C-0437(A) and 072.C-0488(E); from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement.