CMS-PAS-FTR-21-008

CMS-PAS-FTR-21-008
A projection of the precision of the Higgs boson mass measurement in the diphoton decay channel at the High Luminosity LHC
CMS Collaboration
March 2022

Abstract: A projection of the precision with which the mass of the Higgs boson can be measured at the High-Luminosity LHC with the CMS detector in the diphoton decay channel is presented. In this note we summarize the strategy of this projection with an emphasis on the methods employed to mitigate and to quantify the main sources of systematic uncertainty developed for the same measurement using the CMS Run 2 dataset.
Links: CDS record (PDF) ; CADI line (restricted) ;

Figures	Summary	References	CMS Publications

Figures
png pdf	Figure 1-a: The signal shape models for the highest resolution analysis category (left), and the sum of all categories combined together after scaling each of them by the corresponding S/(S+B) ratio (right) for a simulated H $\rightarrow \gamma \gamma$ signal sample with ${m_\mathrm{H}} = $ 125 GeV. The open squares represent weighted simulation events and the blue line the corresponding model. Also shown is the $\sigma _\text {eff}$ value (half the width of the narrowest interval containing 68.3% of the invariant mass distribution) and the full width at half of the maximum (FWHM).
png pdf	Figure 1-b: The signal shape models for the highest resolution analysis category (left), and the sum of all categories combined together after scaling each of them by the corresponding S/(S+B) ratio (right) for a simulated H $\rightarrow \gamma \gamma$ signal sample with ${m_\mathrm{H}} = $ 125 GeV. The open squares represent weighted simulation events and the blue line the corresponding model. Also shown is the $\sigma _\text {eff}$ value (half the width of the narrowest interval containing 68.3% of the invariant mass distribution) and the full width at half of the maximum (FWHM).
png pdf	Figure 2: The likelihood scan of the expected Higgs boson mass in the diphoton decay channel for an integrated luminosity of 3000 fb$^{-1}$. The solid lines are for the full likelihood scan including all systematic uncertainties, while the dashed lines denote the same with the statistical uncertainty only.

Summary

A projection of the precision of the Higgs boson mass, in the diphoton decay channel, with the upgraded CMS detector at the HL-LHC under the scenario of 3000 fb$^{-1}$ integrated luminosity has been performed. The projection methodology adopted is based on the last measurement of $m_{\mathrm{H}}$ in the diphoton decay channel with the 2016 dataset of Run 2 [4], with several improvements implemented in the photon energy calibration procedure which lead to a more precise reconstruction of the photon energy scale. The precision of $m_{\mathrm{H}}$ is thus projected to be $m_{\mathrm{H}} =$ 125.38 $\pm$ 0.02 (stat) $\pm$ 0.07 (syst) GeV.

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	CMS-HIG-12-028 1207.7235
2	ATLAS Collaboration	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	1207.7214
3	L. J. Dixon and Y. Li	Bounding the higgs boson width through interferometry	PRL 111 (Sep, 2013) 111802
4	CMS Collaboration	A measurement of the higgs boson mass in the diphoton decay channel	Physics Letters B 805 (2020) 135425	CMS-HIG-19-004
5	CMS Collaboration	The CMS Experiment at the CERN LHC	JINST 3 (2008) S08004	CMS-00-001
6	CMS Collaboration	Technical Proposal for the Phase-II Upgrade of the CMS Detector	CMS-PAS-TDR-15-002	CMS-PAS-TDR-15-002
7	CMS Collaboration	The Phase-2 Upgrade of the CMS Tracker	CMS-PAS-TDR-17-001	CMS-PAS-TDR-17-001
8	CMS Collaboration	The Phase-2 Upgrade of the CMS Barrel Calorimeters Technical Design Report	CMS-PAS-TDR-17-002	CMS-PAS-TDR-17-002
9	CMS Collaboration	The Phase-2 Upgrade of the CMS Endcap Calorimeter	CMS-PAS-TDR-17-007	CMS-PAS-TDR-17-007
10	CMS Collaboration	The Phase-2 Upgrade of the CMS Muon Detectors	CMS-PAS-TDR-17-003	CMS-PAS-TDR-17-003
11	CMS Collaboration	A MIP Timing Detector for the CMS Phase-2 Upgrade	CMS-PAS-TDR-19-002	CMS-PAS-TDR-19-002
12	CMS Collaboration	The Phase-2 Upgrade of the CMS Level-1 Trigger	CMS-PAS-TDR-20-001	CMS-PAS-TDR-20-001
13	CMS Collaboration	The Phase-2 Upgrade of the CMS Data Acquisition and High Level Trigger	CDS
14	CMS Collaboration	Expected performance of the physics objects with the upgraded CMS detector at the HL-LHC	CDS
15	CMS Collaboration	ECAL 2016 refined calibration and Run2 summary plots	CDS
16	CMS Collaboration	The Phase-2 Upgrade of the CMS Endcap Calorimeter	CMS-PAS-TDR-17-007	CMS-PAS-TDR-17-007
17	CMS Collaboration	Projected performance of Higgs analyses at the HL-LHC for ECFA 2016	CMS-PAS-FTR-16-002	CMS-PAS-FTR-16-002
18	CMS Collaboration	Measurements of Higgs boson properties in the diphoton decay channel in proton-proton collisions at $ \sqrt{s} = $ 13 TeV	JHEP 11 (2018) 185	CMS-HIG-16-040 1804.02716
19	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
20	T. Sjostrand, S. Mrenna, and P. Skands	A Brief Introduction to PYTHIA 8.1	CPC 178 (2007) 852	0710.3820
21	CMS Collaboration	Event generator tunes obtained from underlying event and multiparton scattering measurements	EPJC 76 (2016) 155	CMS-GEN-14-001 1512.00815
22	T. Gleisberg et al.	Event generation with SHERPA 1.1	JHEP 02 (2009) 007	0811.4622
23	J. Alwall et al.	MadGraph 5 : Going Beyond	JHEP 06 (2011) 128	1106.0522
24	GEANT4 Collaboration	GEANT4--a simulation toolkit	NIMA 506 (2003) 250
25	P. D. Dauncey, M. Kenzie, N. Wardle, and G. J. Davies	Handling uncertainties in background shapes: the discrete profiling method	JINST 10 (2015) P04015	1408.6865
26	R. A. Fisher	On the interpretation of $ \chi^2 $ from contingency tables, and the calculation of P	Journal of the Royal Statistical Society 85 (1922) 87
27	T. Junk	Confidence level computation for combining searches with small statistics	NIMA 434 (1999) 435	hep-ex/9902006
28	A. L. Read	Presentation of search results: the CLs technique	Journal of Physics G: Nuclear and Particle Physics 28 (2002) 2693
29	G. Cowan, K. Cranmer, E. Gross, and O. Vitells	Asymptotic formulae for likelihood-based tests of new physics	EPJC 71 (2011) 1554	1007.1727