Publication
Search for long-lived particles that decay into final states containing two electrons or two muons in proton-proton collisions at $\sqrt{s} =$ 8 TeV
| dc.contributor.author | CMS collaboration (2132 authors) | |
| dc.contributor.author | Hollar, Jonathan | |
| dc.contributor.author | Nayak, Aruna | |
| dc.contributor.author | Bargassa, Pedrame | |
| dc.contributor.author | Beirão Da Cruz E Silva, Cristóvão | |
| dc.contributor.author | Faccioli, Pietro | |
| dc.contributor.author | Ferreira Parracho, Pedro Guilherme | |
| dc.contributor.author | Gallinaro, Michele | |
| dc.contributor.author | Lloret Iglesias, Lara | |
| dc.contributor.author | Nguyen, Federico | |
| dc.contributor.author | Rodrigues Antunes, Joao | |
| dc.contributor.author | Seixas, Joao | |
| dc.contributor.author | Varela, Joao | |
| dc.contributor.author | Vischia, Pietro | |
| dc.contributor.author | David Tinoco Mendes, Andre | |
| dc.contributor.author | Silva, Pedro | |
| dc.contributor.author | Musella, Pasquale | |
| dc.contributor.author | Pela, Joao | |
| dc.contributor.author | Leonardo, Nuno | |
| dc.date.accessioned | 2019-02-04T05:31:40Z | |
| dc.date.available | 2019-02-04T05:31:40Z | |
| dc.date.issued | 2015-03-18 | |
| dc.date.updated | 2019-02-04T05:31:40Z | |
| dc.description.abstract | <p>A search is performed for long-lived particles that decay into final states that include a pair of electrons or a pair of muons. The experimental signature is a distinctive topology consisting of a pair of charged leptons originating from a displaced secondary vertex. Events corresponding to an integrated luminosity of <inline-formula><mml:math display="inline"><mml:mrow><mml:mn>19.6</mml:mn><mml:mtext> </mml:mtext><mml:mo stretchy="false">(</mml:mo><mml:mn>20.5</mml:mn><mml:mo stretchy="false">)</mml:mo><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:msup><mml:mrow><mml:mi>fb</mml:mi></mml:mrow><mml:mrow><mml:mo>-</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math></inline-formula> in the electron (muon) channel were collected with the CMS detector at the CERN LHC in proton-proton collisions at <inline-formula><mml:math display="inline"><mml:msqrt><mml:mi>s</mml:mi></mml:msqrt><mml:mo>=</mml:mo><mml:mn>8</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>TeV</mml:mi></mml:math></inline-formula>. No<mml:math display="inline"></mml:math> significant excess is observed above standard model expectations. Upper limits on the product of the cross section and branching fraction of such a signal are presented as a function of the long-lived particle’s mean proper decay length. The limits are presented in an approximately model-independent way, allowing them to be applied to a wide class of models yielding the above topology. Over much of the investigated parameter space, the limits obtained are the most stringent to date. In the specific case of a model in which a Higgs boson in the mass range <inline-formula><mml:math display="inline"><mml:mrow><mml:mn>125</mml:mn><mml:mi>–</mml:mi><mml:mn>1000</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>GeV</mml:mi><mml:mo stretchy="false">/</mml:mo><mml:msup><mml:mrow><mml:mi>c</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math></inline-formula> decays into a pair of long-lived neutral bosons in the mass range <inline-formula><mml:math display="inline"><mml:mrow><mml:mn>20</mml:mn><mml:mi>–</mml:mi><mml:mn>350</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>GeV</mml:mi><mml:mo stretchy="false">/</mml:mo><mml:msup><mml:mrow><mml:mi>c</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math></inline-formula>, each of which can then decay to dileptons, the upper limits obtained are typically in the range 0.2–10 fb for mean proper decay lengths of the long-lived particles in the range 0.01–100 cm. In the case of the lowest Higgs mass considered (<inline-formula><mml:math display="inline"><mml:mrow><mml:mn>125</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>GeV</mml:mi><mml:mo stretchy="false">/</mml:mo><mml:msup><mml:mrow><mml:mi>c</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math></inline-formula>), the limits are in the range 2–50 fb. These limits are sensitive to Higgs boson branching fractions as low as <inline-formula><mml:math display="inline"><mml:mn>1</mml:mn><mml:msup><mml:mn>0</mml:mn><mml:mrow><mml:mo>-</mml:mo><mml:mn>4</mml:mn></mml:mrow></mml:msup></mml:math></inline-formula>.</p> | |
| dc.description.version | Peer Reviewed | |
| dc.identifier | Phys.Rev. D91 (2015) 052012; DOI 10.1103/PhysRevD.91.052012 | |
| dc.identifier.uri | http://dx.doi.org/10.1103/PhysRevD.91.052012 | |
| dc.identifier.uri | http://hdl.handle.net/10400.26/26736 | |
| dc.language.iso | eng | |
| dc.title | Search for long-lived particles that decay into final states containing two electrons or two muons in proton-proton collisions at $\sqrt{s} =$ 8 TeV | |
| dc.type | journal article | |
| dspace.entity.type | Publication | |
| rcaap.rights | openAccess | pt |
| rcaap.type | article |