Search for new particles decaying to a jet and an emerging jet
BMBWF (Austria) ; FWF (Austria) ; FNRS (Belgium) ; FWO (Belgium) ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) ; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) ; Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) ; FAPERGS (Brazil) ; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; MES (Bulgaria) ; CERN ; CAS (China) ; MoST (China) ; NSFC (China) ; COLCIENCIAS (Colombia) ; MSES (Croatia) ; CSF (Croatia) ; RPF (Cyprus) ; SENESCYT (Ecuador) ; MoER (Estonia) ; ERC IUT (Estonia) ; ERDF (Estonia) ; Academy of Finland (Finland) ; MEC (Finland) ; HIP (Finland) ; CEA (France) ; CNRS/IN2P3 (France) ; BMBF (Germany) ; DFG (Germany) ; HGF (Germany) ; GSRT (Greece) ; NKFIA (Hungary) ; DAE (India) ; DST (India) ; IPM (Iran) ; SFI (Ireland) ; INFN (Italy) ; MSIP (Republic of Korea) ; NRF (Republic of Korea) ; MES (Latvia) ; LAS (Lithuania) ; MOE (Malaysia) ; UM (Malaysia) ; BUAP (Mexico) ; CINVESTAV (Mexico) ; CONACYT (Mexico) ; LNS (Mexico) ; SEP (Mexico) ; UASLP-FAI (Mexico) ; MOS (Montenegro) ; MBIE (New Zealand) ; PAEC (Pakistan) ; MSHE (Poland) ; NSC (Poland) ; FCT (Portugal) ; JINR (Dubna) ; MON (Russia) ; RosAtom (Russia) ; RAS (Russia) ; RFBR (Russia) ; NRC KI (Russia) ; MESTD (Serbia) ; SEIDI (Spain) ; CPAN (Spain) ; PCTI (Spain) ; FEDER (Spain) ; MOSTR (Sri Lanka) ; Swiss Funding Agencies (Switzerland) ; MST (Taipei) ; ThEPCenter (Thailand) ; IPST (Thailand) ; STAR (Thailand) ; NSTDA (Thailand) ; TUBITAK (Turkey) ; TAEK (Turkey) ; NASU (Ukraine) ; SFFR (Ukraine) ; STFC (United Kingdom) ; DOE (U.S.A.) ; NSF (U.S.A.) ; Marie-Curie program (European Union) ; European Research Council (European Union) ; Horizon 2020 Grant (European Union) ; Leventis Foundation ; A.P. Sloan Foundation ; Alexander von Humboldt Foundation ; Belgian Federal Science Policy Office ; Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium) ; Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium) ; F.R.S.-FNRS (Belgium) ; Ministry of Education, Youth and Sports (MEYS) of the Czech Republic ; Lendulet (Momentum) Program of the Hungarian Academy of Sciences (Hungary) ; Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences (Hungary) ; New National Excellence Program UNKP (Hungary) ; NKFIA research grants (Hungary) ; Council of Science and Industrial Research, India ; HOMING PLUS program of the Foundation for Polish Science (Poland) ; European Union, Regional Development Fund (Poland) ; Mobility Plus program of the Ministry of Science and Higher Education (Poland) ; National Science Center (Poland) ; National Priorities Research Program by Qatar National Research Fund ; Programa Estatal de Fomento de la Investigacion Cientifica y Tecnica de Excelencia Maria de Maeztu ; Programa Severo Ochoa del Principado de Asturias ; Thalis program - EU-ESF ; Aristeia program - EU-ESF ; Greek NSRF ; Rachadapisek Sompot Fund for Postdoctoral Fellowship, Chulalongkorn University (Thailand) ; Chulalongkorn Academic into Its 2nd Century Project Advancement Project (Thailand) ; Welch Foundation ; Weston Havens Foundation (U.S.A.) ; European Research Council (European Union): 675440 ; Horizon 2020 Grant (European Union): 675440 ; F.R.S.-FNRS (Belgium): 30820817 ; FWO (Belgium): 30820817 ; NKFIA research grants (Hungary): 123842 ; NKFIA research grants (Hungary): 123959 ; NKFIA research grants (Hungary): 124845 ; NKFIA research grants (Hungary): 124850 ; NKFIA research grants (Hungary): 125105 ; HOMING PLUS program of the Foundation for Polish Science (Poland): Harmonia 2014/14/M/ST2/00428 ; HOMING PLUS program of the Foundation for Polish Science (Poland): Opus 2014/13/B/ST2/02543 ; HOMING PLUS program of the Foundation for Polish Science (Poland): 2014/15/B/ST2/03998 ; HOMING PLUS program of the Foundation for Polish Science (Poland): 2015/19/B/ST2/02861 ; HOMING PLUS program of the Foundation for Polish Science (Poland): Sonata-bis 2012/07/E/ST2/01406 ; European Union, Regional Development Fund (Poland): Harmonia 2014/14/M/ST2/00428 ; European Union, Regional Development Fund (Poland): Opus 2014/13/B/ST2/02543 ; European Union, Regional Development Fund (Poland): 2014/15/B/ST2/03998 ; European Union, Regional Development Fund (Poland): 2015/19/B/ST2/02861 ; European Union, Regional Development Fund (Poland): Sonata-bis 2012/07/E/ST2/01406 ; Mobility Plus program of the Ministry of Science and Higher Education (Poland): Harmonia 2014/14/M/ST2/00428 ; Mobility Plus program of the Ministry of Science and Higher Education (Poland): Opus 2014/13/B/ST2/02543 ; Mobility Plus program of the Ministry of Science and Higher Education (Poland): 2014/15/B/ST2/03998 ; Mobility Plus program of the Ministry of Science and Higher Education (Poland): 2015/19/B/ST2/02861 ; Mobility Plus program of the Ministry of Science and Higher Education (Poland): Sonata-bis 2012/07/E/ST2/01406 ; National Science Center (Poland): Harmonia 2014/14/M/ST2/00428 ; National Science Center (Poland): Opus 2014/13/B/ST2/02543 ; National Science Center (Poland): 2014/15/B/ST2/03998 ; National Science Center (Poland): 2015/19/B/ST2/02861 ; National Science Center (Poland): Sonata-bis 2012/07/E/ST2/01406 ; Programa Estatal de Fomento de la Investigacion Cientifica y Tecnica de Excelencia Maria de Maeztu: MDM-2015-0509 ; Welch Foundation: C-1845 ; A search is performed for events consistent with the pair production of a new heavy particle that acts as a mediator between a dark sector and normal matter, and that decays to a light quark and a new fermion called a dark quark. The search is based on data corresponding to an integrated luminosity of 16.1 fb(-1) from proton-proton collisions at =13 TeV collected by the CMS experiment at the LHC in 2016. The dark quark is charged only under a new quantum-chromodynamics-like force, and forms an emerging jet via a parton shower, containing long-lived dark hadrons that give rise to displaced vertices when decaying to standard model hadrons. The data are consistent with the expectation from standard model processes. Limits are set at 95% confidence level excluding dark pion decay lengths between 5 and 225 mm for dark mediators with masses between 400 and 1250 GeV. Decay lengths smaller than 5 and greater than 225 mm are also excluded in the lower part of this mass range. The dependence of the limit on the dark pion mass is weak for masses between 1 and 10 GeV. This analysis is the first dedicated search for the pair production of a new particle that decays to a jet and an emerging jet.