Longitudinal double-spin asymmetry for inclusive jet and dijet production in $pp$ collisions at $\sqrt{s} = 510$ GeV

The STAR collaboration Adam, J. ; Adamczyk, L. ; Adams, J.R. ; et al.
Phys.Rev.D 100 (2019) 052005, 2019.
Inspire Record 1738738 DOI 10.17182/hepdata.105278

We report the first measurement of the inclusive jet and the dijet longitudinal double-spin asymmetries, $A_{LL}$, at midrapidity in polarized $pp$ collisions at a center-of-mass energy $\sqrt{s} = 510$ GeV. The inclusive jet $A_{LL}$ measurement is sensitive to the gluon helicity distribution down to a gluon momentum fraction of $x\approx 0.015$, while the dijet measurements, separated into four jet-pair topologies, provide constraints on the $x$ dependence of the gluon polarization. Both results are consistent with previous measurements made at $\sqrt{s}= 200$ GeV in the overlapping kinematic region, $x > 0.05$, and show good agreement with predictions from recent next-to-leading order global analyses.

56 data tables

Fractions of the next-to-leading-order cross section for inclusive jet production arising from quark-quark, quark-gluon and gluon-gluon scattering in pp collisions (200GeV)

Fractions of the next-to-leading-order cross section for inclusive jet production arising from quark-quark, quark-gluon and gluon-gluon scattering in pp collisions (500GeV)

The upper panel shows the jet yield vs detector jet pT in data and simulation for each of the three trigger categories. The lower three panels show the relative differences between data and simulation (JP0)

More…

Combination of CMS searches for heavy resonances decaying to pairs of bosons or leptons

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Lett.B 798 (2019) 134952, 2019.
Inspire Record 1737724 DOI 10.17182/hepdata.88899

A statistical combination of searches for heavy resonances decaying to pairs of bosons or leptons is presented. The data correspond to an integrated luminosity of 35.9 fb$^{-1}$ collected during 2016 by the CMS experiment at the LHC in proton-proton collisions at a center-of-mass energy of 13 TeV. The data are found to be consistent with expectations from the standard model background. Exclusion limits are set in the context of models of spin-1 heavy vector triplets and of spin-2 bulk gravitons. For mass-degenerate W' and Z' resonances that predominantly couple to the standard model gauge bosons, the mass exclusion at 95% confidence level of heavy vector bosons is extended to 4.5 TeV as compared to 3.8 TeV determined from the best individual channel. This excluded mass increases to 5.0 TeV if the resonances couple predominantly to fermions.

14 data tables

Observed and expected 95% CL upper limits on the product of the cross section and branching fraction of a spin-1 resonance decaying to a pair of SM bosons.

Observed and expected 95% CL upper limits on the product of the cross section and branching fraction of a spin-2 resonance decaying to a pair of SM bosons.

Observed and expected 95% CL upper limits on the product of the cross section of a W' resonance decaying to a pair of SM bosons.

More…

Search for supersymmetry with a compressed mass spectrum in the vector boson fusion topology with 1-lepton and 0-lepton final states in proton-proton collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 08 (2019) 150, 2019.
Inspire Record 1737508 DOI 10.17182/hepdata.88816

A search for supersymmetric particles produced in the vector boson fusion topology in proton-proton collisions is presented. The search targets final states with one or zero leptons, large missing transverse momentum, and two jets with a large separation in rapidity. The data sample corresponds to an integrated luminosity of 35.9 fb$^{-1}$ of proton-proton collisions at $\sqrt{s} =$ 13 TeV collected in 2016 with the CMS detector at the LHC. The observed dijet invariant mass and lepton-neutrino transverse mass spectra are found to be consistent with the standard model predictions. Upper limits are set on the cross sections for chargino ($\widetilde\chi_1^\pm$) and neutralino ($\widetilde\chi_2^0$) production with two associated jets. For a compressed mass spectrum scenario in which the $\widetilde\chi_1^\pm$ and $\widetilde\chi_2^0$ decays proceed via a light slepton and the mass difference between the lightest neutralino $\widetilde\chi_1^0$ and the mass-degenerate particles $\widetilde\chi_1^\pm$ and $\widetilde\chi_2^0$ is 1 (30) GeV, the most stringent lower limit to date of 112 (215) GeV is set on the mass of these latter two particles.

20 data tables

Selection efficiency on signal for each channel.

The observed $m_{T}$ and $m_{jj}$ distributions in the ejj (upper left), $\mu$~jj (upper right), $\tau_{h}$~jj (lower left), and $0\ell$~jj (lower right) signal regions compared with the post-fit SM background yields from the fit described in the text. The pre-fit background yields and shapes are determined using data-driven methods for the major backgrounds, and based on simulation for the smaller backgrounds. Expected signal distributions are overlaid. The last bin in the $m_{T}$ distributions of the $1\ell$~jj channels include all events with $m_{T} > 210$~GeV. The last bin of the $m_{jj}$ distributions of the $0\ell$~jj channel include all events with $m_{jj} > 3800$~GeV.

The observed $m_{T}$ and $m_{jj}$ distributions in the ejj (upper left), $\mu$~jj (upper right), $\tau_{h}$~jj (lower left), and $0\ell$~jj (lower right) signal regions compared with the post-fit SM background yields from the fit described in the text. The pre-fit background yields and shapes are determined using data-driven methods for the major backgrounds, and based on simulation for the smaller backgrounds. Expected signal distributions are overlaid. The last bin in the $m_{T}$ distributions of the $1\ell$~jj channels include all events with $m_{T} > 210$~GeV. The last bin of the $m_{jj}$ distributions of the $0\ell$~jj channel include all events with $m_{jj} > 3800$~GeV.

More…

First measurement of near-threshold J/$\psi $ exclusive photoproduction off the proton

The GlueX collaboration Ali, A. ; Amaryan, M. ; Anassontzis, E.G. ; et al.
Phys.Rev.Lett. 123 (2019) 072001, 2019.
Inspire Record 1736890 DOI 10.17182/hepdata.110173

We report on the measurement of the $\gamma p \rightarrow J/\psi p$ cross section from $E_\gamma = 11.8$ GeV down to the threshold at $8.2$ GeV using a tagged photon beam with the GlueX experiment. We find the total cross section falls toward the threshold less steeply than expected from two-gluon exchange models. The differential cross section $d\sigma /dt$ has an exponential slope of $1.67 \pm 0.39$ GeV$^{-2}$ at $10.7$ GeV average energy. The LHCb pentaquark candidates $P_c^+$ can be produced in the $s$-channel of this reaction. We see no evidence for them and set model-dependent upper limits on their branching fractions $\mathcal{B}(P_c^+ \rightarrow J/\psi p)$ and cross sections $\sigma(\gamma p \to P_c^+)\times\mathcal{B}(P_c^+ \to J/\psi p) $.

2 data tables

$\gamma p \rightarrow J/\psi p$ total cross-sections, statistical and systematic errors of the individual points in bins of beam energy. There is an additional fully correlated systematic uncertainty of 26.7% on the total cross section, not included here.

$\gamma p \rightarrow J/\psi p$ differential cross-sections, statistical and systematic errors of the individual points in bins of $-(t-t_{min})$. There is an additional fully correlated systematic uncertainty of 26.7% on the total cross section, not included here.


Search for Higgs and Z boson decays to J/$\psi$ or $\Upsilon$ pairs in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Lett.B 797 (2019) 134811, 2019.
Inspire Record 1736895 DOI 10.17182/hepdata.90709

A search for decays of the Higgs and Z boson to pairs of J/$\psi$ or $\Upsilon$(nS) (n=1, 2, 3) mesons, with their subsequent decay to $\mu^+\mu^-$ pairs, is presented. The analysis uses data from proton-proton collisions at $\sqrt{s}=$ 13 TeV, collected with the CMS detector at the LHC in 2017 and corresponding to an integrated luminosity of 37.5 fb$^{-1}$. While an observation of such a decay with this sample would indicate the presence of physics beyond the standard model, no significant excess is observed. Upper limits at 95% confidence level are placed on the branching fractions of these decays. In the J/$\psi$ pair channel, the limits are 1.8$\times$10$^{-3}$ and 2.2$\times$10$^{-6}$ for the Higgs and Z boson, respectively, while in the combined $\Upsilon$(nS) pair channel, the limits are 1.4$\times$ 10$^{-3}$ and 1.5$\times$10$^{-6}$, respectively, when the mesons from the Higgs and Z boson decay are assumed to be unpolarized. When fully longitudinal and transverse polarizations are considered the limits reduce by about 22-29% and increase by about 10-13%, respectively.

1 data table

Exclusion limits at 95% CL for the branching fractions ($\mathcal{B}$s) of the $H$ and $Z$ boson decays to $J/\psi$ or $\Upsilon$ mesons pairs. The second column lists the observed limits. The third column shows the median expected limits with the upper and lower bounds in the expected 68% CL intervals.


Search for anomalous electroweak production of vector boson pairs in association with two jets in proton-proton collisions at 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Lett.B 798 (2019) 134985, 2019.
Inspire Record 1735737 DOI 10.17182/hepdata.89398

A search for anomalous electroweak production of WW, WZ, and ZZ boson pairs in association with two jets in proton-proton collisions at $\sqrt{s} =$ 13 TeV at the LHC is reported. The data sample corresponds to an integrated luminosity of 35.9 fb$^{-1}$ collected with the CMS detector. Events are selected by requiring two jets with large rapidity separation and invariant mass, one or two leptons (electrons or muons), and a W or Z boson decaying hadronically. No excess of events with respect to the standard model background predictions is observed and constraints on the structure of quartic vector boson interactions in the framework of dimension-8 effective field theory operators are reported. Stringent limits on parameters of the effective field theory operators are obtained. The observed 95% confidence level limits for the S0, M0, and T0 operators are $-$2.7 $<$ f$_{\mathrm{S0}}/ \Lambda^{4}$ $<$ 2.7, $-$1.0 $<$ f$_{\mathrm{M0}}/ \Lambda^{4}$ $<$ 1.0, and $-$0.17 $<$ f$_{\mathrm{T0}}/ \Lambda^{4}$ $<$ 0.16, in units of TeV$^{-4}$. Constraints are also reported on the product of the cross section and branching fraction for vector boson fusion production of charged Higgs bosons as a function of mass from 600 to 2000 GeV. The results are interpreted in the context of the Georgi-Machacek model.

10 data tables

Expected yields from various background processes in $\mathrm{WV}$ and $\mathrm{ZV}$ final states. The combination of the statistical and systematic uncertainties are shown. The predicted yields are shown with their best-fit normalizations from the background-only fit. The aQGC signal yields are shown for two aQGC scenarios with $f_{T2}/ \Lambda^{4} = -0.5$ TeV$^{-4}$ and $f_{T2}/ \Lambda^{4} = -2.5$ TeV$^{-4}$ for the $\mathrm{WV}$ and $\mathrm{ZV}$ channels, respectively. The charged Higgs boson signal yields are also shown for values of $s_{\mathrm{H}}=0.5$ and $m_{\mathrm{H}_{5}}=500$ GeV in the GM model. The statistical uncertainties are shown for the expected signal yields.

Observed and expected lower and upper 95\% CL limits on the parameters of the quartic operators S0, S1, M0, M1, M6, M7, T0, T1, and T2 in $\mathrm{WV}$ and $\mathrm{ZV}$ channels. The last two columns show the observed and expected limits for the combination of the $\mathrm{WV}$ and $\mathrm{ZV}$ channels.

Expected and observed exclusion limits at the 95\% CL as a function of $m(\mathrm{H}^{\pm})$ for $\sigma_\mathrm{VBF}(\mathrm{H}^{\pm}) \, \mathcal{B}(\mathrm{H}^{\pm} \rightarrow \mathrm{W}^{\pm}\mathrm{Z})$ in the $\mathrm{WV}$ final state.

More…

Version 2
Search for a light charged Higgs boson decaying to a W boson and a CP-odd Higgs boson in final states with e$\mu\mu$ or $\mu\mu\mu$ in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev.Lett. 123 (2019) 131802, 2019.
Inspire Record 1735729 DOI 10.17182/hepdata.89938

A search for a light charged Higgs boson (H$^+$) decaying to a W boson and a CP-odd Higgs boson (A) in final states with e$\mu\mu$ or $\mu\mu\mu$ is performed using data from pp collisions at $\sqrt{s}=$ 13 TeV, recorded by the CMS detector at the LHC and corresponding to an integrated luminosity of 35.9 fb$^{-1}$. In this search, it is assumed that the H$^+$ boson is produced in decays of top quarks, and the A boson decays to two oppositely charged muons. The presence of signals for H$^+$ boson masses between 100 and 160 GeV and A boson masses between 15 and 75 GeV is investigated. No evidence for the production of the H$^+$ boson is found. Upper limits at 95% confidence level are obtained on the combined branching fraction for the decay chain t $\to$ bH$^+$ $\to$ bW$^+$A $\to$ bW$^+\mu^+\mu^-$, of 1.9 $\times$ 10$^{-6}$ to 8.6 $\times$ 10$^{-6}$, depending on the masses of the H$^+$ and A bosons. These are the first limits for these decay modes of the H$^+$ and A bosons.

4 data tables

Expected and observed upper limits at 95% CL on the branching fraction of the top quark, $\mathcal{B}(\mathrm{t}\to\mathrm{b}\mathrm{H^{+}})$, for the A boson masses ($\mathit{m}_{\mathrm{A}}$), with an assumption of the $\mathrm{H^{+}}$ boson mass $\mathit{m}_{\mathrm{H^{+}}}=\mathit{m}_{\mathrm{A}}$+85 GeV. In the calculation, the $t\overline{t}$ production cross section is set to 832 pb, and the branching fractions $\mathcal{B}(\mathrm{A}\to\mu^{+}\mu^{-})$ and $\mathcal{B}(\mathrm{H^{+}}\to\mathrm{W^{+}}\mathrm{A})$ are assumed to be $3\times10^{-4}$ and 1, respectively.

Expected and observed upper limits at 95% CL on $\mathcal{B}_{sig}=\mathcal{B}(\mathrm{t}\to\mathrm{b}\mathrm{H^{+}})\mathcal{B}(\mathrm{H^{+}}\to\mathrm{W^{+}}\mathrm{A})\mathcal{B}(\mathrm{A}\to\mu^{+}\mu^{-})$ for the A boson masses ($\mathit{m}_{\mathrm{A}}$). The $\mathrm{H^{+}}$ boson mass is assumed to be $\mathit{m}_{\mathrm{A}}$+85 GeV in the calculation.

Expected and observed upper limits at 95% CL on the branching fraction of the top quark, $\mathcal{B}(\mathrm{t}\to\mathrm{b}\mathrm{H^{+}})$, for the A boson masses ($\mathit{m}_{\mathrm{A}}$), with an assumption of the $\mathrm{H^{+}}$ boson mass $\mathit{m}_{\mathrm{H^{+}}}$ = 160 GeV. In the calculation, the $t\overline{t}$ production cross section is set to 832 pb, and the branching fractions $\mathcal{B}(\mathrm{A}\to\mu^{+}\mu^{-})$ and $\mathcal{B}(\mathrm{H^{+}}\to\mathrm{W^{+}}\mathrm{A})$ are assumed to be $3\times10^{-4}$ and 1, respectively.

More…

Search for the production of W$^\pm$W$^\pm$W$^\mp$ events at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev.D 100 (2019) 012004, 2019.
Inspire Record 1734235 DOI 10.17182/hepdata.89176

A search for the production of events containing three W bosons predicted by the standard model is reported. The search is based on a data sample of proton-proton collisions at a center-of-mass energy of 13 TeV recorded by the CMS experiment at the CERN LHC and corresponding to a total integrated luminosity of 35.9 fb$^{-1}$. The search is performed in final states with three leptons (electrons or muons), or with two same-charge leptons plus two jets. The observed (expected) significance of the signal for W$^\pm$W$^\pm$W$^\mp$ production is 0.60 (1.78) standard deviations, and the ratio of the measured signal yield to that expected from the standard model is 0.34 $^{+0.62}_{-0.34}$. Limits are placed on three anomalous quartic gauge couplings and on the production of massive axionlike particles.

9 data tables

Lost-lepton and three-lepton background contributions.

Non-prompt lepton background estimates.

Summary of typical systematic uncertainties of estimated background contributions.

More…

Observation of nuclear modifications in W$^\pm$ boson production in pPb collisions at $\sqrt{s_\mathrm{NN}} =$ 8.16 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Lett.B 800 (2020) 135048, 2020.
Inspire Record 1733223 DOI 10.17182/hepdata.88284

The production of W$^\pm$ bosons is studied in proton-lead (pPb) collisions at a nucleon-nucleon centre-of-mass energy of $\sqrt{s_\mathrm{NN}} =$ 8.16 TeV. Measurements are performed in the W$^\pm$ $\to$ $\mu^\pm\nu_\mu$ channel using a data sample corresponding to an integrated luminosity of 173.4 $\pm$ 8.7 nb$^{-1}$, collected by the CMS Collaboration at the LHC. The number of positively and negatively charged W bosons is determined separately in the muon pseudorapidity region in the laboratory frame $|\eta^\mu_\mathrm{lab}|$ $<$ 2.4 and transverse momentum $p_\mathrm{T}^\mu$ $>$ 25 GeV/$c$. The W$^\pm$ boson differential cross sections, muon charge asymmetry, and the ratios of W$^\pm$ boson yields for the proton-going over the Pb-going beam directions are reported as a function of the muon pseudorapidity in the nucleon-nucleon centre-of-mass frame. The measurements are compared to the predictions from theoretical calculations based on parton distribution functions (PDFs) at next-to-leading-order. The results favour PDF calculations that include nuclear modifications and provide constraints on the nuclear PDF global fits.

7 data tables

Muon charge asymmetry, $(N_{\mu}^{+} - N_{\mu}^{-})/(N_{\mu}^{+} + N_{\mu}^{-})$, as a function of the muon pseudorapidity in the centre-of-mass frame.

Differential production cross sections for $\textrm{pPb} \to W^{+} + X \to \mu^{+} \nu + X$ for positively charged muons of $p_T$ larger than 25 GeV$/c$, in nanobarns, as a function of the muon pseudorapidity in the centre-of-mass frame. The global normalisation uncertainty of 3.5% is listed separately.

Differential production cross sections for $\textrm{pPb} \to W^{-} + X \to \mu^{-} \bar{\nu} + X$ for negatively charged muons of $p_T$ larger than 25 GeV$/c$, in nanobarns, as a function of the muon pseudorapidity in the centre-of-mass frame. The global normalisation uncertainty of 3.5% is listed separately.

More…

Multiparticle correlation studies in pPb collisions at $\sqrt{s_\mathrm{NN}} =$ 8.16 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev.C 101 (2020) 014912, 2020.
Inspire Record 1731568 DOI 10.17182/hepdata.88288

The second- and third-order azimuthal anisotropy Fourier harmonics of charged particles produced in pPb collisions, at $\sqrt{s_\mathrm{NN}} =$ 8.16 TeV, are studied over a wide range of event multiplicities. Multiparticle correlations are used to isolate global properties stemming from the collision overlap geometry. The second-order "elliptic" harmonic moment is obtained with high precision through four-, six-, and eight-particle correlations and, for the first time, the third-order "triangular" harmonic moment is studied using four-particle correlations. A sample of peripheral PbPb collisions at $\sqrt{s_\mathrm{NN}} =$ 5.02 TeV that covers a similar range of event multiplicities as the pPb results is also analyzed. Model calculations of initial-state fluctuations in pPb and PbPb collisions can be directly compared to the high precision experimental results. This work provides new insight into the fluctuation-driven origin of the $v_3$ coefficients in pPb and PbPb collisions, and into the dominating overall collision geometry in PbPb collisions at the earliest stages of heavy ion interactions.

14 data tables

$v_2\{4\}$ as a function of $N_{trk}^{offline}$ in PbPb collisions at $\sqrt{s_{NN}} = 5.02$ TeV.

$v_2\{6\}$ as a function of $N_{trk}^{offline}$ in PbPb collisions at $\sqrt{s_{NN}} = 5.02$ TeV.

$v_2\{8\}$ as a function of $N_{trk}^{offline}$ in PbPb collisions at $\sqrt{s_{NN}} = 5.02$ TeV.

More…