CMS logoCMS event Hgg
Compact Muon Solenoid
LHC, CERN

CMS-PAS-FTR-22-005
Search for dark matter in final states with a Higgs boson decaying to a pair of b-jets and missing transverse momentum at the HL-LHC
Abstract: We perform a projection study for the sensitivity of the upgraded CMS detector to new physics in a mono-Higgs sector, h $\to$ bb plus missing transverse momentum final state, at the HL-LHC. The focus lies on signals with boosted Higgs bosons, resulting in a large radius jet containing both b quarks that can are identified as originating from a Higgs boson. The search is sensitive to a variety of BSM models and in this analysis the results are interpreted in terms of 2HDM+a model. We find that with a data set corresponding to 3000 fb$^{-1}$, $m_{\text{A}}$ masses from 750 to 2000 GeV could be excluded for $m_{\text{a}} = $ 250 GeV and $m_{\text{A}}$ masses from 1250 to 1600 GeV could be excluded for $m_{\text{a}} = $ 500 GeV. The 2HDM+a signals with $m_{\text{a}} = $ 250 and $m_{\text{A}}= $ 1000-1600 GeV, which are not yet excluded, could reach a significance near 5$\sigma$.
Figures & Tables Summary References CMS Publications
Figures

png pdf
Figure 1:
The pseudoscalar A decaying into the light pseudoscalar a and the observed Higgs boson h in a 2HDM+a model.

png pdf
Figure 2:
SM background predictions and expectations for two signal benchmark scenarios: 2HDM+a model with $m_{\mathrm{A} }=$ 1750 GeV, $m_{{\mathrm{a}}} = $ 250 GeV (solid line) and $m_{\mathrm{A} }=$ 1750 GeV, $m_{{\mathrm{a}}} = $ 750 GeV (dashed line). The systematic and statistical uncertainties in each bin after fitting are given by the shaded regions. The lower panel shows the relative uncertainties in each bin. The last bin of each ${m_{\mathrm {T}}}$ distribution contains the overflow.

png pdf
Figure 3:
Expected limits on the signal strength for a 2HDM+a model of DM production in association with $\mathrm{h} \to \mathrm{b} {}\mathrm{\bar{b}} + {{p_{\mathrm {T}}} ^\text {miss}} $. Limits are produced for varying values of $m_{\mathrm{A} }$ and $m_{{\mathrm{a}}}$ with $\sin\theta =$ 0.35, $\tan\beta =$ 1, and $m_{\chi}=$ 10 GeV. The shaded region reflects the 1$\sigma $ uncertainty band.

png pdf
Figure 4:
Expected significance of a 2HDM+a model of DM production in association with $\mathrm{h} \to \mathrm{b} {}\mathrm{\bar{b}} + {{p_{\mathrm {T}}} ^\text {miss}} $ produced for varying values of $m_{\mathrm{A} }$ and $m_{{\mathrm{a}}}$ with $\sin\theta =$ 0.35, $\tan\beta =$ 1, and $m_\chi =$ 10 GeV.
Tables

png pdf
Table 1:
Summary of the event selection.

png pdf
Table 2:
Summary of the effect of the systematic uncertainties used in this analysis on the yields.
Summary
This analysis is a search for Higgs boson decays into a pair of b quarks with high ${p_{\mathrm{T}}}^{\text{miss}}$ to probe the sensitivity of the HL-LHC to the production of dark matter in association with the Higgs boson. Several advances in technology and Phase-2 upgrades to the CMS detector will improve the ability to search for this final state, including improved heavy object tagging and increased geometric acceptance in the detector during the HL-LHC era. We interpret our results through a two Higgs doublet model, extended by a light pseudoscalar boson (2HDM+\mathrm{a}), by determining limits on the cross-section of the associated production for various masses of pseudoscalars a and A. We determine that the Phase-2 upgrades will enable the exclusion of a wide range of mass points. $m_{\mathrm{A} }$ values between 750 and 2000 GeV could be excluded for $m_{\mathrm{a}} = $ 250, while $m_{\mathrm{A} }$ values between 1250 and 1600 GeV could be excluded for $m_{\mathrm{a}} = $ 500. Signal points unconstrained by Run 2 searches with $m_{\mathrm{a}} = $ 250 GeV and $m_{\mathrm{A} }$ between 1000-1600 GeV could reach a significance close to 5$\sigma$.
References
1 Planck Collaboration Planck 2018 results. VI. Cosmological parameters Astron. Astrophys. 641 (2020) A6 1807.06209
2 G. Bertone, D. Hooper, and J. Silk Particle dark matter: Evidence, candidates and constraints PR 405 (2005) 279--390 hep-ph/0404175
3 A. A. Petrov and W. Shepherd Searching for dark matter at LHC with Mono-Higgs production PLB 730 (2014) 178--183 1311.1511
4 L. Carpenter et al. Mono-Higgs-boson: A new collider probe of dark matter PRD 89 (2014), no. 7, 075017 1312.2592
5 A. Berlin, T. Lin, and L.-T. Wang Mono-Higgs Detection of Dark Matter at the LHC JHEP 06 (2014) 078 1402.7074
6 ATLAS Collaboration Search for Dark Matter in Events with Missing Transverse Momentum and a Higgs Boson Decaying to Two Photons in $ pp $ Collisions at $ \sqrt{s}= $ 8 TeV with the ATLAS Detector PRL 115 (2015), no. 13, 131801 1506.01081
7 ATLAS Collaboration Search for Dark Matter Produced in Association with a Higgs Boson Decaying to $ b\bar b $ using 36 fb$ ^{-1} $ of $ pp $ collisions at $ \sqrt s= $ 13 TeV with the ATLAS Detector PRL 119 (2017), no. 18, 181804 1707.01302
8 CMS Collaboration Search for dark matter produced in association with a Higgs boson decaying to a pair of bottom quarks in proton-proton collisions at $ \sqrt{s}=$ 13 TeV EPJC 79 (2019), no. 3, 280 CMS-EXO-16-050
1811.06562
9 ATLAS Collaboration Search for dark matter produced in association with a Standard Model Higgs boson decaying into b-quarks using the full Run 2 dataset from the ATLAS detector JHEP 11 (2021) 209 2108.13391
10 M. Bauer, U. Haisch, and F. Kahlhoefer Simplified dark matter models with two higgs doublets: I. pseudoscalar mediators Journal of High Energy Physics 2017 (May, 2017) 1701.07427
11 CMS Collaboration The CMS Experiment at the CERN LHC JINST 3 (2008) S08004 CMS-00-001
12 CMS Collaboration Technical Proposal for the Phase-II Upgrade of the CMS Detector CMS-PAS-TDR-15-002 CMS-PAS-TDR-15-002
13 CMS Collaboration The Phase-2 Upgrade of the CMS Tracker CMS-PAS-TDR-17-001 CMS-PAS-TDR-17-001
14 CMS Collaboration The Phase-2 Upgrade of the CMS Barrel Calorimeters Technical Design Report CMS-PAS-TDR-17-002 CMS-PAS-TDR-17-002
15 CMS Collaboration The Phase-2 Upgrade of the CMS Endcap Calorimeter CMS-PAS-TDR-17-007 CMS-PAS-TDR-17-007
16 CMS Collaboration The Phase-2 Upgrade of the CMS Muon Detectors CMS-PAS-TDR-17-003 CMS-PAS-TDR-17-003
17 C. CMS A MIP Timing Detector for the CMS Phase-2 Upgrade technical report, CERN, Geneva, Mar
18 CMS Collaboration Collaboration The Phase-2 Upgrade of the CMS Level-1 Trigger technical report, CERN, Geneva, Apr, 2020 Final version
19 C. Collaboration The Phase-2 Upgrade of the CMS Data Acquisition and High Level Trigger technical report, CERN, Geneva, Mar, 2021 This is a temporary submission, just to get the LHCC reference number, to be used in this and other CMS documents
20 CMS Collaboration Expected performance of the physics objects with the upgraded CMS detector at the HL-LHC CDS
21 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
22 K. Mimasu, V. Sanz, and C. Williams Higher Order QCD predictions for Associated Higgs production with anomalous couplings to gauge bosons JHEP 08 (2016) 039 1512.02572
23 P. Nason A new method for combining NLO QCD with shower Monte Carlo algorithms JHEP 11 (2004) 040 hep-ph/0409146
24 S. Frixione, P. Nason, and C. Oleari Matching NLO QCD computations with Parton Shower simulations: the POWHEG method JHEP 11 (2007) 070 0709.2092
25 S. Alioli, P. Nason, C. Oleari, and E. Re A general framework for implementing NLO calculations in shower Monte Carlo programs: the POWHEG BOX JHEP 06 (2010) 043 1002.2581
26 J. M. Campbell, R. K. Ellis, P. Nason, and E. Re Top-pair production and decay at NLO matched with parton showers JHEP 04 (2015) 114 1412.1828
27 S. Alioli, P. Nason, C. Oleari, and E. Re NLO single-top production matched with shower in POWHEG: $ s $- and $ t $-channel contributions JHEP 09 (2009) 111 0907.4076
28 S. Frixione, P. Nason, and G. Ridolfi A positive-weight next-to-leading-order Monte Carlo for heavy flavour hadroproduction JHEP 09 (2007) 126 0707.3088
29 M. Aliev et al. HATHOR: HAdronic Top and Heavy quarks crOss section calculatoR CPC 182 (2011) 1034 1007.1327
30 P. Kant et al. HatHor for single top-quark production: Updated predictions and uncertainty estimates for single top-quark production in hadronic collisions CPC 191 (2015) 74 1406.4403
31 LHC Higgs Cross Section Working Group Collaboration, D. de Florian et al. Handbook of LHC Higgs Cross Sections: 4. Deciphering the Nature of the Higgs Sector volume 2/2017 CERN, 10
32 T. Sjostrand et al. An introduction to PYTHIA 8.2 CPC 191 (2015) 159 1410.3012
33 P. Skands, S. Carrazza, and J. Rojo Tuning PYTHIA 8.1: the Monash 2013 tune EPJC 74 (2014) 3024 1404.5630
34 CMS Collaboration Event generator tunes obtained from underlying event and multiparton scattering measurements EPJC 76 (2016) 155 CMS-GEN-14-001
1512.00815
35 CMS Collaboration Extraction and validation of a new set of CMS PYTHIA8 tunes from underlying-event measurements EPJC 80 (2020) 4 CMS-GEN-17-001
1903.12179
36 NNPDF Collaboration Parton distributions for the LHC Run II JHEP 04 (2015) 040 1410.8849
37 NNPDF Collaboration Parton distributions from high-precision collider data EPJC 77 (2017) 663 1706.00428
38 J. Alwall et al. Comparative study of various algorithms for the merging of parton showers and matrix elements in hadronic collisions EPJC 53 (2008) 473 0706.2569
39 J. de Favereau et al. Delphes 3: a modular framework for fast simulation of a generic collider experiment Journal of High Energy Physics 2014 (Feb, 2014) 1307.6346
40 M. Selvaggi DELPHES 3: A modular framework for fast-simulation of generic collider experiments J. Phys. Conf. Ser. 523 (2014) 012033
41 M. Selvaggi Delphes 3: Latest Developments J. Phys. Conf. Ser. 762 (2016), no. 1, 012051
42 M. Cacciari, G. P. Salam, and G. Soyez The anti-$ k_t $ jet clustering algorithm JHEP 04 (2008) 063 0802.1189
43 D. Bertolini, P. Harris, M. Low, and N. Tran Pileup Per Particle Identification JHEP 10 (2014) 059 1407.6013
44 A. J. Larkoski, S. Marzani, G. Soyez, and J. Thaler Soft Drop JHEP 05 (2014) 146 1402.2657
45 H. Qu and L. Gouskos ParticleNet: Jet Tagging via Particle Clouds PRD 101 (2020), no. 5, 056019 1902.08570
46 G. Cowan, K. Cranmer, E. Gross, and O. Vitells Asymptotic formulae for likelihood-based tests of new physics The European Physical Journal C 71 (Feb, 2011)
47 T. Junk Confidence level computation for combining searches with small statistics Nucl. Instr. Meth. A 434 (1999) 435 hep-ex/9902006
48 A. L. Read Presentation of search results: the CL$ _{\textrm{s}} $ technique JPG 28 (2002) 2693
Compact Muon Solenoid
LHC, CERN