CMS-PAS-B2G-20-001

CMS-PAS-B2G-20-001
Search for resonances decaying to triple W-boson final states in proton-proton collisions at $\sqrt{s}= $ 13 TeV
CMS Collaboration
April 2021

Abstract: The first search for resonances decaying into a radion and a W boson in proton-proton collision data recorded by the CMS detector at $\sqrt{s} = $ 13 TeV corresponding to an integrated luminosity of 137 fb$^{-1}$ is reported. The radion is reconstructed through its decay into two W bosons. We require the presence of one isolated lepton and missing transverse momentum from a leptonic W boson decay, and either one or two massive large-radius jets containing the decay products of the other two W bosons. No excess over the background estimation is observed and upper limits are set on model parameters.
Links: CDS record (PDF) ; inSPIRE record ; CADI line (restricted) ; These preliminary results are superseded in this paper, Submitted to PRL. The superseded preliminary plots can be found here.

Figures	Summary	References	CMS Publications

Figures
png pdf	Figure 1: Feynman-like diagrams for the decay of a Kaluza-Klein excitation resonance $ {{\rm W}_{\mathrm {KK}}}$ decaying to the final states considered in this analysis. Left: three individually reconstructed W bosons; right: one individually reconstructed W boson and two W bosons reconstructed as a single large-radius jet.
png pdf	Figure 2: Leading jet mass $ {{\rm M}_{{\rm j}}}$ for a triboson signal with $ {{\rm M}_{{{\rm W}_{\mathrm {KK}}}}} = $ 3.5 TeV and $ {{\rm M}_{{\mathrm {R}}}} = $ 0.21 TeV split into the different signal categories and normalized to the theoretical prediction for the signal production cross section. The percentages indicated in the legend correspond to the relative category fractions for this signal point.
png pdf	Figure 3: The deep-WH discriminant for a triboson signal with $ {{\rm M}_{{{\rm W}_{\mathrm {KK}}}}} = $ 3.5 TeV and $ {{\rm M}_{{\mathrm {R}}}} = $ 0.21 TeV split into the different signal categories (dashed and dotted lines) and for jets from background processes (full line).
png pdf	Figure 4: Background-only post-fit distribution of the reconstructed $\ell \nu $+jets system ${{\rm M}_{\mathrm {jj\ell}\nu}}$ in data and simulation for SR4. The shape of a triboson signal with $ {{\rm M}_{{{\rm W}_{\mathrm {KK}}}}} = $ 2.5 TeV and $ {{\rm M}_{{\mathrm {R}}}} = $ 1 TeV is shown in violet.
png pdf	Figure 5: Pull (Data$-$Prediction$/\sigma _{\mathrm {stat}}$) distributions of the background-only fit to the reconstructed $\ell \nu $+jets system ${{\rm M}_{\mathrm {j\ell}\nu}} ({{\rm M}_{\mathrm {jj\ell}\nu}})$ for all SRs. Post-fit systematic uncertainties are indicated by the shaded bands. Exemplary signal points normalized to the theoretical prediction for the signal production cross section are shown using full and dashed lines.
png pdf	Figure 6: Expected and observed upper limits at 95% CL on the signal cross section as functions of the ${{\rm W}_{\mathrm {KK}}} and {\mathrm {R}}$ resonance masses.

Summary

In summary, we have presented for the first time a search for resonances decaying in cascade through ${{\rm W}_{\mathrm {KK}}} \rightarrow \mathrm{W}\mathrm{R}$ and $\mathrm{R} \rightarrow \mathrm{W}\mathrm{W}$ to three W bosons, where ${{\rm W}_{\mathrm {KK}}}$ is a Kaluza-Klein excited massive gauge boson and R is a scalar radion. The search has been performed in proton-proton collision data at a center-of-mass energy of 13 TeV, corresponding to total integrated luminosity of 137 fb$^{-1}$. The final states analyzed manifest themselves in one isolated lepton, missing transverse momentum, and one or two massive large radius jets. Both regimes with two W bosons merged in a single WW jet and with two separated W boson jets are simultaneously probed. Results are found to agree with the predictions of the standard model. Limits are set on model parameters, which are the first on the production of triboson resonances at the LHC.

References
1	ATLAS Collaboration	Combination of searches for heavy resonances decaying into bosonic and leptonic final states using 36 fb$^{-1}$ of proton-proton collision data at $ \sqrt{s} = $ 13 TeV with the ATLAS detector	PRD (2018) 052008	1808.02380
2	CMS Collaboration	Combination of CMS searches for heavy resonances decaying to pairs of bosons or leptons	PLB (2019) 134952	CMS-B2G-18-006 1906.00057
3	R. Kogler et al.	Jet Substructure at the Large Hadron Collider: Experimental Review	Rev. Mod. Phys. 91 (2019), no. 4, 045003	1803.06991
4	K. Agashe, P. Du, S. Hong, and R. Sundrum	Flavor Universal Resonances and Warped Gravity	JHEP 01 (2017) 016	1608.00526
5	K. S. Agashe et al.	LHC Signals from Cascade Decays of Warped Vector Resonances	JHEP 05 (2017) 078	1612.00047
6	K. Agashe et al.	Dedicated Strategies for Triboson Signals from Cascade Decays of Vector Resonances	PRD 99 (2019), no. 7, 075016	1711.09920
7	J. Aguilar-Saavedra	Profile of multiboson signals	JHEP 05 (2017) 066	1703.06153
8	K. Agashe et al.	Detecting a Boosted Diboson Resonance	JHEP 11 (2018) 027	1809.07334
9	Y.-P. Kuang, H.-Y. Ren, and L.-H. Xia	Further investigation of the model-independent probe of heavy neutral Higgs bosons at LHC Run 2	CPC 40 (2016), no. 2, 023101	1506.08007
10	H.-Y. Ren, L.-H. Xia, and Y.-P. Kuang	Model-independent Probe of anomalous heavy neutral Higgs bosons at the LHC	PRD 90 (2014), no. 11, 115002	1404.6367
11	L. Randall and R. Sundrum	A large mass hierarchy from a small extra dimension	PRL 83 (1999) 3370	hep-ph/9905221
12	L. Randall and R. Sundrum	An alternative to compactification	PRL 83 (1999) 4690	hep-th/9906064
13	K. Agashe, H. Davoudiasl, G. Perez, and A. Soni	Warped gravitons at the LHC and beyond	PRD 76 (2007) 036006	hep-ph/0701186
14	A. L. Fitzpatrick, J. Kaplan, L. Randall, and L.-T. Wang	Searching for the Kaluza-Klein graviton in bulk RS models	JHEP 09 (2007) 013	hep-ph/0701150
15	CMS Collaboration	The CMS experiment at the CERN LHC	JINST 3 (2008) S08004	CMS-00-001
16	J. Alwall et al.	The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations	JHEP 07 (2014) 079	1405.0301
17	S. Alioli, S.-O. Moch, and P. Uwer	Hadronic top-quark pair-production with one jet and parton showering	JHEP 01 (2012) 137	1110.5251
18	CMS Collaboration	Event generator tunes obtained from underlying event and multiparton scattering measurements	EPJC 76 (2016) 155	CMS-GEN-14-001 1512.00815
19	CMS Collaboration	Extraction and validation of a new set of CMS PYTHIA8 tunes from underlying-event measurements	Submitted to EPJC	CMS-GEN-17-001 1903.12179
20	NNPDF Collaboration	Parton distributions for the LHC Run II	JHEP 04 (2015) 040	1410.8849
21	NNPDF Collaboration	Parton distributions from high-precision collider data	EPJC 77 (2017) 663	1706.00428
22	GEANT4 Collaboration	GEANT4--a simulation toolkit	NIMA 506 (2003) 250
23	CMS Collaboration	The CMS trigger system	JINST 12 (2017) P01020	CMS-TRG-12-001 1609.02366
24	CMS Collaboration	Particle-flow reconstruction and global event description with the CMS detector	JINST 12 (2017) P10003	CMS-PRF-14-001 1706.04965
25	M. Cacciari, G. P. Salam, and G. Soyez	FastJet user manual	EPJC 72 (2012) 1896	1111.6097
26	M. Cacciari, G. P. Salam, and G. Soyez	The anti-$ {k_{\mathrm{T}}} $ jet clustering algorithm	JHEP 04 (2008) 063	0802.1189
27	CMS Collaboration	Identification of heavy-flavour jets with the CMS detector in pp collisions at 13 TeV	JINST 13 (2018) P05011	CMS-BTV-16-002 1712.07158
28	M. Dasgupta, A. Fregoso, S. Marzani, and G. P. Salam	Towards an understanding of jet substructure	JHEP 09 (2013) 029	1307.0007
29	J. M. Butterworth, A. R. Davison, M. Rubin, and G. P. Salam	Jet substructure as a new Higgs search channel at the LHC	PRL 100 (2008) 242001	0802.2470
30	A. J. Larkoski, S. Marzani, G. Soyez, and J. Thaler	Soft drop	JHEP 05 (2014) 146	1402.2657
31	CMS Collaboration	Search for a heavy resonance decaying to a pair of vector bosons in the lepton plus merged jet final state at $ \sqrt{s}= $ 13 TeV	JHEP 05 (2018) 088	CMS-B2G-16-029 1802.09407
32	CMS Collaboration	Identification of heavy, energetic, hadronically decaying particles using machine-learning techniques	JINST 15 (2020), no. 06, P06005	CMS-JME-18-002 2004.08262
33	M. Bahr et al.	Herwig++ Physics and Manual	EPJC 58 (2008) 639--707	0803.0883
34	G. Cowan, K. Cranmer, E. Gross, and O. Vitells	Asymptotic formulae for likelihood-based tests of new physics	EPJC 71 (2011) 1554	1007.1727
35	A. L. Read	Presentation of search results: The CL$ _{\text{s}} $ technique	JPG 28 (2002) 2693
36	T. Junk	Confidence level computation for combining searches with small statistics	NIMA 434 (1999) 435	hep-ex/9902006