CMS logoCMS event Hgg
Compact Muon Solenoid
LHC, CERN

CMS-PAS-HIG-15-009
Search for a light pseudo-scalar Higgs boson produced in association with bottom quarks in pp collisions at $ \sqrt{s} = $ 8 TeV
Abstract: We report on the search for a light pseudo-scalar Higgs boson produced in association with a bottom quark and decaying into dimuons. The search makes use of 19.8 fb$^{-1}$ of proton-proton collisions at a center-of-mass energy of 8 TeV, collected by the CMS experiment at the LHC. No signal is observed in the search for a pseudo-scalar Higgs boson and upper limits on the cross section times branching fraction are set.
Figures Summary References CMS Publications
Figures

png pdf
Figure 1:
The transverse momentum of the leading (left) and the subleading (right) ${p_{\mathrm {T}}}$ muon.

png pdf
Figure 1-a:
The transverse momentum of the leading ${p_{\mathrm {T}}}$ muon.

png pdf
Figure 1-b:
The transverse momentum of the subleading ${p_{\mathrm {T}}}$ muon.

png pdf
Figure 2:
Left: the transverse momentum of the leading ${p_{\mathrm {T}}}$ bottom-quark tagged jet. Right: the missing transverse energy (MET).

png pdf
Figure 2-a:
The transverse momentum of the leading ${p_{\mathrm {T}}}$ bottom-quark tagged jet.

png pdf
Figure 2-b:
The missing transverse energy (MET).

png pdf
Figure 3:
The dimuon mass with the expected background event yield and its uncertainty and with the expected signal for $\rm m_{A}= $ 30 GeV assuming the signal cross section times branching fraction of 350 fb. Left: with the use of PF jets; right: with the use of JPT jets.

png pdf
Figure 3-a:
The dimuon mass with the expected background event yield and its uncertainty and with the expected signal for $\rm m_{A}= $ 30 GeV assuming the signal cross section times branching fraction of 350 fb, with the use of PF jets.

png pdf
Figure 3-b:
The dimuon mass with the expected background event yield and its uncertainty and with the expected signal for $\rm m_{A}= $ 30 GeV assuming the signal cross section times branching fraction of 350 fb, with the use of JPT jets.

png pdf
Figure 4:
Cross-check with the $\rm e^{+}e^{-}$ final state. The dielectron mass spectrum with the expected background event yield and its uncertainty.

png pdf
Figure 5:
Left: the dimuon mass with the post-fit background event yield and its uncertainty given by the fit and the expected signal for $\rm m_{A}= $ 30 GeV assuming the signal cross section times branching fraction of 350 fb. Right: the expected and observed upper limit at 95% CL on $\sigma (\mathrm {pp \rightarrow b\bar{b}A)} \times \mathcal {B} \mathrm {(A}\rightarrow \mu \mu )$ as a function of the dimuon mass. The circles show the limits obtained in the CMS analysis of the $\mathrm {A}\rightarrow \tau \tau $ final state [7] and recalculated into the limits for the $\mathrm {A}\rightarrow \mu \mu $ final state using Eq.(1).

png pdf
Figure 5-a:
The dimuon mass with the post-fit background event yield and its uncertainty given by the fit and the expected signal for $\rm m_{A}= $ 30 GeV assuming the signal cross section times branching fraction of 350 fb.

png pdf
Figure 5-b:
The expected and observed upper limit at 95% CL on $\sigma (\mathrm {pp \rightarrow b\bar{b}A)} \times \mathcal {B} \mathrm {(A}\rightarrow \mu \mu )$ as a function of the dimuon mass. The circles show the limits obtained in the CMS analysis of the $\mathrm {A}\rightarrow \tau \tau $ final state [7] and recalculated into the limits for the $\mathrm {A}\rightarrow \mu \mu $ final state using Eq.(1).

png pdf
Figure 6:
The transverse momentum of the leading (left) and the subleading (right) ${p_{\mathrm {T}}}$ muon.

png pdf
Figure 6-a:
The transverse momentum of the leading ${p_{\mathrm {T}}}$ muon.

png pdf
Figure 6-b:
The transverse momentum of the subleading ${p_{\mathrm {T}}}$ muon.

png pdf
Figure 7:
Left: the transverse momentum of the leading ${p_{\mathrm {T}}}$ bottom-quark tagged jet. Right: the missing transverse energy (MET).

png pdf
Figure 7-a:
The transverse momentum of the leading ${p_{\mathrm {T}}}$ bottom-quark tagged jet.

png pdf
Figure 7-b:
The missing transverse energy (MET).

png pdf
Figure 8:
The dimuon mass with the expected background event yield and its uncertainty and with the expected signal for $\rm m_{A}= $ 30 GeV assuming the signal cross section times branching fraction of 350 fb. Left: with the use of PF jets; right: with the use of JPT jets.

png pdf
Figure 8-a:
The dimuon mass with the expected background event yield and its uncertainty and with the expected signal for $\rm m_{A}= $ 30 GeV assuming the signal cross section times branching fraction of 350 fb, with the use of PF jets.

png pdf
Figure 8-b:
The dimuon mass with the expected background event yield and its uncertainty and with the expected signal for $\rm m_{A}= $ 30 GeV assuming the signal cross section times branching fraction of 350 fb, with the use of JPT jets.

png pdf
Figure 9:
Cross-check with the $\rm e^{+}e^{-}$ final state. The dielectron mass spectrum with the expected background event yield and its uncertainty.

png pdf
Figure 10:
Left: the dimuon mass with the post-fit background event yield and its uncertainty given by the fit and the expected signal for $\rm m_{A}=30 GeV $ assuming the signal cross section times branching fraction of 350 fb. Right: the expected and observed upper limit at 95% CL on $\sigma (\mathrm {pp \rightarrow b\bar{b}A)} \times \mathcal {B} \mathrm {(A}\rightarrow \mu \mu )$ as a function of the dimuon mass. The circles show the limits obtained in the CMS analysis of the $\mathrm {A}\rightarrow \tau \tau $ final state [7] and recalculated into the limits for the $\mathrm {A}\rightarrow \mu \mu $ final state using formula $\frac {\mathcal {B}\mathrm {(A}\rightarrow \tau \tau )}{\mathcal {B}\mathrm {(A}\rightarrow \mu \mu )}= [ m_{\tau} / m_{\mu} ]^2 $.

png pdf
Figure 10-a:
The dimuon mass with the post-fit background event yield and its uncertainty given by the fit and the expected signal for $\rm m_{A}=30 GeV $ assuming the signal cross section times branching fraction of 350 fb.

png pdf
Figure 10-b:
The expected and observed upper limit at 95% CL on $\sigma (\mathrm {pp \rightarrow b\bar{b}A)} \times \mathcal {B} \mathrm {(A}\rightarrow \mu \mu )$ as a function of the dimuon mass. The circles show the limits obtained in the CMS analysis of the $\mathrm {A}\rightarrow \tau \tau $ final state [7] and recalculated into the limits for the $\mathrm {A}\rightarrow \mu \mu $ final state using formula $\frac {\mathcal {B}\mathrm {(A}\rightarrow \tau \tau )}{\mathcal {B}\mathrm {(A}\rightarrow \mu \mu )}= [ m_{\tau} / m_{\mu} ]^2 $.
Summary
A light pseudo-scalar Higgs boson produced in association with a pair of b-jets and decaying into two muons has been searched for in pp collisions at $ \sqrt{s} = $ 8 TeV with an integrated luminosity of 19.8 fb$^{-1}$. No signal has been observed in the dimuon mass region of 25-60 GeV. Upper limits on the cross section times branching fraction, $\sigma(\mathrm{pp \rightarrow b\bar{b}A)} \times \mathcal{B}\mathrm{(A}\rightarrow\mu\mu)$ obtained have been set. The limits evaluated from the direct search for the $\mathrm{A} \rightarrow \mu\mu$ decay in the associated $\rm b \bar{b} A$ production are comparable with the upper limits from the search for the $\mathrm{A}\rightarrow\tau\tau$ final state from the same production process. It demonstrates the importance of the $\mu\mu$ final state for the overal experimental sensitivity in searches for $\rm b \bar{b}A$ production. This complementarity of the two final states can become particularly important should future larger data sets start revealing evidence of potential new physics.
References
1 CMS Collaboration Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC PLB 716 (2012) 30 -- 61
2 G. Aad et al. Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC PLB 716 (2012) 1 -- 29
3 ATLAS and CMS Collaborations Combined Measurement of the Higgs Boson Mass in $ \mathrm{ p }\mathrm{ p } $ Collisions at $ \sqrt{s}=$ 7 and 8 TeV with the ATLAS and CMS Experiments PRL 114 (2015) 191803 1503.07589
4 J. F. Gunion, H. E. Haber, G. L. Kane, and S. Dawson The Higgs Hunter's Guide Front. Phys. 80 (2000)1--448
5 G. Branco et al. Theory and phenomenology of two-Higgs-doublet models PR 516 (2012) 1--102 1106.0034
6 J. Bernon, J. F. Gunion, Y. Jiang, and S. Kraml Light Higgs bosons in Two-Higgs-Doublet Models PRD 91 (2015) 075019 1412.3385
7 CMS Collaboration Search for a low-mass pseudoscalar Higgs boson produced in association with a $ b\bar{b} $ pair in pp collisions at $ \sqrt{s} = $ 8 TeV PLB758 (2016) 296--320 CMS-HIG-14-033
1511.03610
8 CMS Collaboration Searches for light pseudoscalar bosons in the decay of the SM-like Higgs boson in pp collisions at $ \sqrt{s} = $ 8 TeV
9 CMS Collaboration The CMS experiment at the CERN LHC JINST 3 (2008) S08004 CMS-00-001
10 CMS Collaboration Performance of CMS muon reconstruction in pp collision events at $ \sqrt{s}=$ 7 TeV JINST 7 (2012) P10002 CMS-MUO-10-004
1206.4071
11 CMS Collaboration Observation of a new boson with mass near 125 GeV in pp collisions at $ \sqrt{s} = $ 7 and 8 TeV JHEP 6 (2013) 81 CMS-HIG-12-036
1303.4571
12 S. Baffioni et al. Electron reconstruction in CMS EPJC 49 (2007) 1099
13 CMS Collaboration Performance of Jet-Plus-Tracks algorithm in Run I CMS-PAS-JME-14-005 CMS-PAS-JME-14-005
14 CMS Collaboration Particle--Flow Event Reconstruction in CMS and Performance for Jets, Taus, and $ E_{\mathrm{T}}^{\text{miss}} $ CDS
15 CMS Collaboration Commissioning of the Particle-flow Event Reconstruction with the first LHC collisions recorded in the CMS detector CDS
16 CMS Collaboration Commissioning of the Particle-flow Event reconstruction in Minimum-Bias and Jet Events from pp Collisions at $ \sqrt{s} = $ 7 TeV CDS
17 M. Cacciari, G. P. Salam, and G. Soyez The anti-$ k_t $ jet clustering algorithm JHEP 04 (2008) 063 0802.1189
18 M. Cacciari, G. P. Salam, and G. Soyez FastJet user manual EPJC 72 (2012) 1896 1111.6097
19 CMS Collaboration Pileup Jet Identification CMS-PAS-JME-13-005 CMS-PAS-JME-13-005
20 M. Cacciari and G. P. Salam Pileup subtraction using jet areas PLB 659 (2008) 119 0707.1378
21 M. Cacciari, G. P. Salam, and G. Soyez The Catchment Area of Jets JHEP 804 (2008) 5 0802.1188
22 M. Cacciari, G. P. Salam, and G. Soyez FastJet User Manual EPJC 72 (2012) 1896 1111.6097
23 CMS Collaboration Missing transverse energy performance of the CMS detector JINST 6 (2011) 9001 CMS-JME-10-009
1106.5048
24 CMS Collaboration Identification and filtering of uncharacteristic noise in the CMS hadron calorimeter JINST 5 (2009) T03014
25 CMS Collaboration Determination of jet energy calibration and transverse momentum resolution in CMS JINST 6 (2011) 11002 CMS-JME-10-011
1107.4277
26 A. Hoecker et al. TMVA: Toolkit for Multivariate Data Analysis PoS ACAT (2007) 040 physics/0703039
27 CMS Collaboration Collaboration Performance of b tagging at $ \sqrt{s} = $ 8 TeV in multijet, ttbar and boosted topology events
28 T. Sjostrand, S. Mrenna, and P. Z. Skands PYTHIA 6.4 physics and manual JHEP 05 (2006) 026 hep-ph/0603175
29 R. Field Min-Bias and the Underlying Event at the LHC 1110.5530
30 R. Field Studying the underline event at CDF and the LHC Proceedings of the First International Workshop on Multiple Partonic Interactions at the LHC MPI'08 October 27-31 (2008)
31 J. Alwall et al. MadGraph 5: going beyond JHEP 06 (2011) 128 1106.0522
32 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
33 J. Pumplin et al. New generation of parton distributions with uncertainties from global QCD analysis JHEP 07 (2002) 012 hep-ph/0201195
34 M. L. Mangano, M. Moretti, F. Piccinini, and M. Treccani Matching matrix elements and shower evolution for top-quark production in hadronic collisions JHEP 01 (2007) 013 hep-ph/0611129
35 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
36 K. Melnikov and F. Petriello Electroweak gauge boson production at hadron colliders through $ \mathcal{O}(\alpha_S^2) $ PRD 74 (2006) 114017 hep-ph/0609070
37 M. Czakon, P. Fiedler, and A. Mitov The total top quark pair production cross-section at hadron colliders through $ \mathcal{O}(\alpha_S^4) $ PRL 110 (2013) 252004 1303.6254
38 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
39 P. Nason A new method for combining NLO QCD with shower Monte Carlo algorithms JHEP 11 (2004) 040 hep-ph/0409146
40 S. Frixione, P. Nason, and C. Oleari Matching NLO QCD computations with parton shower simulations: the POWHEG method JHEP 11 (2007) 070 0709.2092
41 N. Kidonakis Differential and total cross sections for top pair and single top production in Proceedings of the XX International Workshop on Deep-Inelastic Scattering and Related Subjects Bonn, Germany 1205.3453
42 N. Kidonakis Top Quark Production 1311.0283
43 T. Gehrmann et al. $ \mathrm{ W^{+} }\mathrm{ W^{-} } $ production at hadron colliders in NNLO QCD 1408.5243
44 J. M. Campbell and R. K. Ellis MCFM for the Tevatron and the LHC Nucl. Phys. B Proc. Suppl. 205-206 (2010) 10 1007.3492
45 J. Allison et al. Geant4 developments and applications IEEE Trans. Nucl. Sci. 53 (2006) 270
46 GEANT4 Collaboration GEANT4---a simulation toolkit NIMA 506 (2003) 250
47 CMS Collaboration Search for Higgs Boson Production in Association with a Top-Quark Pair and Decaying to Bottom Quarks or Tau Leptons CMS-PAS-HIG-13-019 CMS-PAS-HIG-13-019
48 S. I. Bityukov and N. V. Krasnikov New physics discovery potential in future experiments physics/9811025
49 R. Frederix et al. W and $ Z/\gamma* $ boson production in association with a bottom-antibottom pair JHEP 09 (2011) 061 1106.6019
50 H.-L. Lai et al. New parton distributions for collider physics PRD 82 (2010) 074024 1007.2241
51 A. D. Martin, W. J. Stirling, R. S. Thorne, and G. Watt Heavy-quark mass dependence in global PDF analyses and 3- and 4-flavour parton distributions EPJC 70 (2010) 51--72 1007.2624
52 R. D. Ball et al. Parton distributions with LHC data Nucl. Phys. B 867 (2013) 244--289 1207.1303
53 M. Wiesemann et al. Higgs production in association with bottom quarks JHEP 1502 (2015) 132 1409.5301
54 J. Butterworth et al. PDF4LHC recommendations for LHC Run II JPG43 (2016) 023001 1510.03865
55 NNPDF Collaboration Parton distributions for the LHC Run II JHEP 04 (2015) 040 1410.8849
56 S. Dulat et al. New parton distribution functions from a global analysis of quantum chromodynamics PRD 93 (2016), no. 3, 033006 1506.07443
57 L. A. Harland-Lang, A. D. Martin, P. Motylinski, and R. S. Thorne Parton distributions in the LHC era: MMHT 2014 PDFs EPJC 75 (2015), no. 5, 204 1412.3989
58 G. Cowan, K. Cranmer, E. Gross, and O. Vitells Asymptotic formulae for likelihood-based tests of new physics EPJC 71 (2011) 1554 1007.1727
59 A. L. Read Linear interpolation of histograms NIMA 425 (1999) 357--360
60 R. Brun and F. Rademakers ROOT: An object oriented data analysis framework NIMA 389 (1997) 81--86
Compact Muon Solenoid
LHC, CERN