Date

Subject_areas

Measurement of the forward-backward asymmetry in $Z/\gamma^{\ast} \rightarrow \mu^{+}\mu^{-}$ decays and determination of the effective weak mixing angle

The LHCb collaboration Aaij, Roel ; Adeva, Bernardo ; Adinolfi, Marco ; et al.
JHEP 1511 (2015) 190, 2015.
Inspire Record 1394859 DOI 10.17182/hepdata.76490

The forward-backward charge asymmetry for the process $ q\overline{q}\to Z/{\gamma}^{\ast}\to {\mu}^{+}{\mu}^{-} $ is measured as a function of the invariant mass of the dimuon system. Measurements are performed using proton proton collision data collected with the LHCb detector at $ \sqrt{s}=7 $ and 8 TeV, corresponding to integrated luminosities of 1 fb$^{−1}$ and 2 fb$^{−1}$ respectively. Within the Standard Model the results constrain the effective electroweak mixing angle to be $ { \sin}^2{\theta}_{\mathrm{W}}^{\mathrm{eff}}=0.23142\pm 0.00073\pm 0.00052\pm 0.00056, $ where the first uncertainty is statistical, the second systematic and the third theoretical. This result is in agreement with the current world average, and is one of the most precise determinations at hadron colliders to date.

2 data tables

Values for $A_{\rm{FB}}$ with the statistical and positive and negative systematic uncertainties for $\sqrt{s}$ = 7 TeV data. The theoretical uncertainties presented in this table, corresponding to the PDF, scale and FSR uncertainties described in Sec. 5, affect only the predictions of $A_{\rm{FB}}$ and the sin$^2\theta^{\rm{eff}}_{\rm W}$ determination, and do not apply to the uncertainties on the measured $A_{\rm{FB}}$.

Values for $A_{\rm{FB}}$ with the statistical and positive and negative systematic uncertainties for $\sqrt{s}$ = 8 TeV data. The theoretical uncertainties presented in this table, corresponding to the PDF, scale and FSR uncertainties described in Sec. 5, affect only the predictions of $A_{\rm{FB}}$ and the sin$^2\theta^{\rm{eff}}_{\rm W}$ determination, and do not apply to the uncertainties on the measured $A_{\rm{FB}}$.


Forward production of $\Upsilon$ mesons in $pp$ collisions at $\sqrt{s}=7$ and 8TeV

The LHCb collaboration Aaij, Roel ; Adeva, Bernardo ; Adinolfi, Marco ; et al.
JHEP 1511 (2015) 103, 2015.
Inspire Record 1392456 DOI 10.17182/hepdata.249

The production of Υ mesons in pp collisions at $ \sqrt{s}=7 $ and 8 TeV is studied with the LHCb detector using data samples corresponding to an integrated luminosity of 1 fb$^{−1}$ and 2 fb$^{−1}$ respectively. The production cross-sections and ratios of cross-sections are measured as functions of the meson transverse momentum p and rapidity y, for p < 30 GeV/c and 2.0 < y < 4.5.

22 data tables

Double-differential cross-section $\mathrm{d}^2 \sigma ( pp \to ( \Upsilon \to \mu^+ \mu^- ) X ) / \mathrm{d} p_T/\mathrm{d}y$ [pb/(GeV/$c$)] for $2.0 < y < 2.5$.

Double-differential cross-section $\mathrm{d}^2 \sigma ( pp \to ( \Upsilon \to \mu^+ \mu^- ) X ) / \mathrm{d} p_T/\mathrm{d}y$ [pb/(GeV/$c$)] for $2.0 < y < 2.5$.

Double-differential cross-section $\mathrm{d}^2 \sigma ( pp \to ( \Upsilon \to \mu^+ \mu^- ) X ) / \mathrm{d} p_T/\mathrm{d}y$ [pb/(GeV/$c$)].

More…

Forward–backward asymmetry of Drell–Yan lepton pairs in pp collisions at $\sqrt{s} = 8$ $\,\mathrm{TeV}$

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Eur.Phys.J. C76 (2016) 325, 2016.
Inspire Record 1415949 DOI 10.17182/hepdata.73121

A measurement of the forward–backward asymmetry ${A}_{\mathrm{FB}}$ of oppositely charged lepton pairs ( $\mu \mu $ and $\mathrm{e}\mathrm{e}$ ) produced via $\mathrm{Z}/\gamma ^*$ boson exchange in pp collisions at $\sqrt{s} = 8$ $\,\mathrm{TeV}$ is presented. The data sample corresponds to an integrated luminosity of 19.7 $\,\mathrm{fb}^{-1}$ collected with the CMS detector at the LHC. The measurement of ${A}_{\mathrm{FB}}$ is performed for dilepton masses between 40 $\,\text {GeV}$ and 2 $\,\mathrm{TeV}$ and for dilepton rapidity up to 5. The ${A}_{\mathrm{FB}}$ measurements as a function of dilepton mass and rapidity are compared with the standard model predictions.

40 data tables

Unfolded combined measurements of AFB in each M-|y| bin (mu+mu- and e+e- combined).

Unfolded measurement of AFB for the forward rapidity region (e+e-).

Unfolded measurements of AFB in each M-|y| bin (mu+mu-).

More…

Measurement of the Z boson differential cross section in transverse momentum and rapidity in proton–proton collisions at 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B749 (2015) 187-209, 2015.
Inspire Record 1359450 DOI 10.17182/hepdata.68945
4 data tables

Measured double differential fiducial cross section normalised to the inclusive fiducial cross section. The uncertainty indicates the total experimental uncertainties (statistical and systematic added in quadrature).

Measured absolute double differential fiducial cross section. The uncertainty indicates the total experimental uncertainties (statistical and systematic added in quadrature).

Covariance matrix of total experimental uncertainties (statistical and systematic uncertainties added in quadrature) of double differential fiducial cross section normalised to the inclusive fiducial cross section. The bin index is PT_i + 10*y_j.

More…

Measurements of differential and double-differential Drell-Yan cross sections in proton-proton collisions at 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Eur.Phys.J. C75 (2015) 147, 2015.
Inspire Record 1332509 DOI 10.17182/hepdata.69869

Measurements of the differential and double-differential Drell–Yan cross sections in the dielectron and dimuon channels are presented. They are based on proton–proton collision data at $\sqrt{s} = 8\,\text {TeV} $ recorded with the CMS detector at the LHC and corresponding to an integrated luminosity of 19.7 $\,\text {fb}^{-1}$ . The measured inclusive cross section in the $\mathrm{Z}$ peak region (60–120 $\,\text {GeV}$ ), obtained from the combination of the dielectron and dimuon channels, is $1138 \pm 8\,\text {(exp)} \pm 25\,\text {(theo)} \pm 30\,\text {(lumi)} \text {\,pb} $ , where the statistical uncertainty is negligible. The differential cross section $\mathrm{d}\sigma /\mathrm{d}{}m$ in the dilepton mass range 15–2000 $\,\text {GeV}$ is measured and corrected to the full phase space. The double-differential cross section $\mathrm{d}^2\sigma /\mathrm{d}{}m\,\mathrm{d}|y |$ is also measured over the mass range 20 to 1500 $\,\text {GeV}$ and absolute dilepton rapidity from 0 to 2.4. In addition, the ratios of the normalized differential cross sections measured at $\sqrt{s} = 7$ and 8 $\,\text {TeV}$ are presented. These measurements are compared to the predictions of perturbative QCD at next-to-leading and next-to-next-to-leading (NNLO) orders using various sets of parton distribution functions (PDFs). The results agree with the NNLO theoretical predictions computed with fewz 3.1 using the CT10 NNLO and NNPDF2.1 NNLO PDFs. The measured double-differential cross section and ratio of normalized differential cross sections are sufficiently precise to constrain the proton PDFs.

15 data tables

Absolute Drell-Yan cross section measurements in the Z peak region (60 < m < 120 GeV). The uncertainties in the measurements include the experimental and theoretical systematic sources and the uncertainty in the integrated luminosity. The statistical component is negligible.

The Drell-Yan differential pre-FSR cross section D(SIG)/DM as measured in the combined dilepton channel for the full phase space. Theoretical uncertainty on acceptance is included.

The Drell-Yan pre-FSR dilepton rapidity distribution D(SIG)/DABS(YRAP) within the detector acceptance, for the mass bin 20-30 GeV, as measured in the combined dilepton channel.

More…

Angular coefficients of Z bosons produced in pp collisions at $\sqrt{s}$ = 8 TeV and decaying to $\mu^+ \mu^-$ as a function of transverse momentum and rapidity

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B750 (2015) 154-175, 2015.
Inspire Record 1359451 DOI 10.17182/hepdata.69285

Measurements of the five most significant angular coefficients, A[0] through A[4], for Z bosons produced in pp collisions at $\sqrt{s}$ = 8 TeV and decaying to $\mu^+ \mu^-$ are presented as a function of the transverse momentum and rapidity of Z boson. The integrated luminosity of the dataset collected with the CMS detector at the LHC corresponds to 19.7 inverse femtobarns. These measurements provide comprehensive information about Z boson production mechanisms, and are compared to QCD predictions at leading order, next-to-leading order, and next-to-next-to-leading order in perturbation theory.

2 data tables

The five angular coefficients A0 to A4 and A0-A2 in bins of qT for |y| < 1.

The five angular coefficients A0 to A4 and A0-A2 in bins of qT for 1 < |y| < 2.1.


Search for contact interactions and large extra dimensions in the dilepton channel using proton-proton collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Eur.Phys.J. C74 (2014) 3134, 2014.
Inspire Record 1305430 DOI 10.17182/hepdata.65760
10 data tables

Reconstructed dielectron mass distributions for data and the SM background estimate.

Reconstructed dimuon mass distributions for data and the SM background estimate.

Reconstructed $\cos\theta^*$ distributions for data and the SM background estimate in the dielectron channel.

More…

Measurement of the differential and double-differential Drell-Yan cross sections in proton-proton collisions at $\sqrt{s} =$ 7 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 1312 (2013) 030, 2013.
Inspire Record 1262319 DOI 10.17182/hepdata.62207

Measurements of the differential and double-differential Drell-Yan cross sections are presented using an integrated luminosity of 4.5(4.8) inverse femtobarns in the dimuon (dielectron) channel of proton-proton collision data recorded with the CMS detector at the LHC at $\sqrt{s}$ = 7 TeV. The measured inclusive cross section in the Z-peak region (60-120 GeV) is $\sigma(\ell \ell)$ = 986.4 +/- 0.6 (stat.) +/- 5.9 (exp. syst.) +/- 21.7 (th. syst.) +/- 21.7 (lum.) pb for the combination of the dimuon and dielectron channels. Differential cross sections $d\sigma/dm$ for the dimuon, dielectron, and combined channels are measured in the mass range 15 to 1500 GeV and corrected to the full phase space. Results are also presented for the measurement of the double-differential cross section $d^2\sigma/dm d |y|$ in the dimuon channel over the mass range 20 to 1500 GeV and absolute dimuon rapidity from 0 to 2.4. These measurements are compared to the predictions of perturbative QCD calculations at next-to-leading and next-to-next-to-leading orders using various sets of parton distribution functions.

10 data tables

Normalization factors for the cross section measurements from the Z-peak region (60 < M < 120 GeV) with associated uncertainties. The measurements are given in the muon, electron and combined channels. The three systematic uncertainties correspond to experimental, theoretical and luminosity.

The DY cross section measurements for the muon channel normalized to the Z-peak region, pre- and post-FSR, as measured in the full acceptance and for the CMS detector acceptance. The uncertainty indicates the experimental (statistical and systematic) uncertainties summed in quadrature with the theoretical uncertainty resulting from the model-dependent kinematic distributions inside each bin.

The DY cross section measurements for the electron channel normalized to the Z-peak region, pre- and post-FSR, as measured in the full acceptance and for the CMS detector acceptance. The uncertainty indicates the experimental (statistical and systematic) uncertainties summed in quadrature with the theoretical uncertainty resulting from the model-dependent kinematic distributions inside each bin.

More…

Search for contact interactions and large extra dimensions in dilepton events from $pp$ collisions at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Phys.Rev. D87 (2013) 015010, 2013.
Inspire Record 1198341 DOI 10.17182/hepdata.60277

A search for non-resonant new phenomena, originating from either contact interactions or large extra spatial dimensions, has been carried out using events with two isolated electrons or muons. These events, produced at the LHC in proton-proton collisions at sqrt(s) = 7 TeV, were recorded by the ATLAS detector. The data sample, collected throughout 2011, corresponds to an integrated luminosity of 4.9 and 5.0 fb-1 in the e+e- and mu+mu- channels, respectively. No significant deviations from the Standard Model expectation are observed. Using a Bayesian approach, 95% confidence limit lower limits ranging from 9.0 to 13.9 TeV are placed on the energy scale of llqq contact interactions in the left-left isoscalar model. Lower limits ranging from 2.4 to 3.9 TeV are also set on the string scale in large extra dimension models. After combination of these limits with results from a similar search in the diphoton channel, slightly more stringent limits are obtained.

7 data tables

Expected and observed numbers of events in the dielectron channel for the contact interactions search region. The yields are normalized to the Z peak control region and include predictions for SM backgrounds as well as for SM+CI with different CI scales for constructive (LAMBDA-) and destructive (LAMBDA+) interference. The errors quoted originate from both systematic uncertainties and limited MC statistics.

Expected and observed numbers of events in the dimuon channel for the contact interactions search region. The yields are normalized to the Z peak control region and include predictions for SM backgrounds as well as for SM+CI with different CI scales for constructive (LAMBDA-) and destructive (LAMBDA+) interference. The errors quoted originate from both systematic uncertainties and limited MC statistics.

Expected and observed 95% C.L. lower limits on the contact interaction energy scale LAMBDA for the dielectron and dimuon channels, as well as for the combination of those channels. Results are provided for constructive and destruc- tive interference as well as different choices of flat priors.

More…

Search for high-mass resonances decaying to dilepton final states in pp collisions at s**(1/2) = 7-TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
JHEP 1211 (2012) 138, 2012.
Inspire Record 1185259 DOI 10.17182/hepdata.59903
14 data tables

Expected and observed number of events in the dielectron channel. The errors quoted include both statistical and systematic uncertainties.

Expected and observed number of events in the dimuon channel. The errors quoted include both statistical and systematic uncertainties.

Observed and predicted dielectron invariant mass (m_ee) distribution in the search region. The bin width is constant in log(m_ee).

More…

Heavy flavour decay muon production at forward rapidity in proton–proton collisions at $\sqrt{s} =$ 7 TeV

The ALICE collaboration Abelev, Betty ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Lett. B708 (2012) 265-275, 2012.
Inspire Record 1084981 DOI 10.17182/hepdata.58676

The production of muons from heavy flavour decays is measured at forward rapidity in proton--proton collisions at \sqrt(s) = 7 TeV collected with the ALICE experiment at the LHC. The analysis is carried out on a data sample corresponding to an integrated luminosity L_{int} = 16.5 nb^{-1}. The transverse momentum and rapidity differential production cross sections of muons from heavy flavour decays are measured in the rapidity range 2.5 < y < 4, over the transverse momentum range 2 < p_{t} < 12 GeV/c. The results are compared to predictions based on perturbative QCD calculations.

7 data tables

pT-differential production cross section of muons from heavy flavour decays, in the rapidity range 2.5<y<4.

y-differential production cross section of muons from heavy flavour decays, in the range 2<pT<12 GeV/C.

pT-differential production cross section of muons from heavy flavour decays, in the rapidity range 2.5<y<2.8.

More…

Measurement of the Drell-Yan Cross Section in $pp$ Collisions at $\sqrt{s}=7$ TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 1110 (2011) 007, 2011.
Inspire Record 921788 DOI 10.17182/hepdata.57980

The Drell-Yan differential cross section is measured in pp collisions at sqrt(s) = 7 TeV, from a data sample collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 36 inverse picobarns. The cross section measurement, normalized to the measured cross section in the Z region, is reported for both the dimuon and dielectron channels in the dilepton invariant mass range 15-600 GeV. The normalized cross section values are quoted both in the full phase space and within the detector acceptance. The effect of final state radiation is also identified. The results are found to agree with theoretical predictions.

3 data tables

The DY spectrum normalized to the Z0 region and to the mass bin widths.

The DY spectrum normalized to the Z0 region for the dimuon channel. Results are for within the detector acceptance(DET) and full phase space both before (POST-FSR) and after final state raduiation corrections.

The DY spectrum normalized to the Z0 region for the dielectron channel. Results are for within the detector acceptance(DET) and full phase space both before (POST-FSR) and after final state raduiation corrections.


Measurement of $\Upsilon$ Production for $p+p$ and $p+d$ Interactions at 800 GeV/c

The NuSea collaboration Zhu, L.Y. ; Reimer, Paul E. ; Mueller, B.A. ; et al.
Phys.Rev.Lett. 100 (2008) 062301, 2008.
Inspire Record 763967 DOI 10.17182/hepdata.42715

We report a high statistics measurement of Upsilon production with an 800 GeV/c proton beam on hydrogen and deuterium targets. The dominance of the gluon-gluon fusion process for Upsilon production at this energy implies that the cross section ratio, $\sigma (p + d \to \Upsilon) / 2\sigma (p + p\to \Upsilon)$, is sensitive to the gluon content in the neutron relative to that in the proton. Over the kinematic region 0 < x_F < 0.6, this ratio is found to be consistent with unity, in striking contrast to the behavior of the Drell-Yan cross section ratio $\sigma(p+d)_{DY}/2\sigma(p+p)_{DY}$. This result shows that the gluon distributions in the proton and neutron are very similar. The Upsilon production cross sections are also compared with the p+d and p+Cu cross sections from earlier measurements.

4 data tables

Differential cross section per nucleon as a function of Feynman X for UPSILON production on the DEUT target.

Differential cross section per nucleon as a function of Feynman X for UPSILON production on the P target.

Differential cross section per nucleon as a function of transverse momentum for UPSILON production on the DEUT target.

More…

J / psi, psi' and Drell-Yan production in p p and p d interactions at 450-GeV/c

The NA51 collaboration Abreu, M.C. ; Alessandro, B. ; Baldit, A. ; et al.
Phys.Lett. B438 (1998) 35-40, 1998.
Inspire Record 481781 DOI 10.17182/hepdata.46539
4 data tables

The measured cross section for J/PSI production for P P and P DEUTERIUM interactions times their branching ratio to MU+ MU- pairs.. The fraction of the systematic error (DSYS) which must be taken into account in comparison of the two targets is 0.06 (0.13) for the P (DEUT) target.

The measured cross section for PSI(3685) production in P P and P DEUTERIUM interactions times their branching ratio to MU+ MU- pairs.. The fraction of the systematic error (DSYS) which must be taken into account in comparison of the two targets is 0.003 (0.006) for the P (DEUT) target.

The measured cross section for Drell Yan production in P P and P DEUTERIUM interactions.. The fraction of the systematic error (DSYS) which must be taken into account in comparison of the two targets is 0.5 (1.2) for the P (DEUT) target.

More…

Absolute Drell-Yan dimuon cross-sections in 800 GeV / c pp and pd collisions

The NuSea collaboration Webb, J.C. ; Awes, T.C. ; Brooks, M.L. ; et al.
No Journal Information, 2003.
Inspire Record 613362 DOI 10.17182/hepdata.41970

The Fermilab E866/NuSea Collaboration has measured the Drell-Yan dimuon cross sections in 800 GeV/$c$ $pp$ and $pd$ collisions. This represents the first measurement of the Drell-Yan cross section in $pp$ collisions over a broad kinematic region and the most extensive study to date of the Drell-Yan cross section in $pd$ collisions. The results indicate that recent global parton distribution fits provide a good description of the light antiquark sea in the nucleon over the Bjorken-$x$ range $0.03 \lesssim x < 0.15$, but overestimate the valence quark distributions as $x \to 1$.

32 data tables

Measurment of the scaling form of the MU+ MU- cross section in the XL range-0.05 to 0.05 from the hydrogen target.

Measurment of the scaling form of the MU+ MU- cross section in the XL range0.05 to 0.10 from the hydrogen target.

Measurment of the scaling form of the MU+ MU- cross section in the XL range0.10 to 0.15 from the hydrogen target.

More…

Measurement of the light anti-quark flavor asymmetry in the nucleon sea

The NuSea collaboration Hawker, E.A. ; Awes, T.C. ; Beddo, M.E. ; et al.
Phys.Rev.Lett. 80 (1998) 3715-3718, 1998.
Inspire Record 468098 DOI 10.17182/hepdata.42153

A precise measurement of the ratio of Drell-Yan yields from an 800 GeV/c proton beam incident on hydrogen and deuterium targets is reported. Over 140,000 Drell-Yan muon pairs with dimuon mass M_{mu+ mu-} >= 4.5 GeV/c^2 were recorded. From these data, the ratio of anti-down (dbar) to anti-up (ubar) quark distributions in the proton sea is determined over a wide range in Bjorken-x. A strong x dependence is observed in the ratio dbar/ubar, showing substantial enhancement of dbar with respect to ubar for x<0.2. This result is in fair agreement with recent parton distribution parameterizations of the sea. For x>0.2, the observed dbar/ubar ratio is much nearer unity than given by the parameterizations.

1 data table

No description provided.


Improved measurement of the anti-d / anti-u asymmetry in the nucleon sea

The NuSea collaboration Towell, R.S. ; McGaughey, P.L. ; Awes, T.C. ; et al.
Phys.Rev. D64 (2001) 052002, 2001.
Inspire Record 554316 DOI 10.17182/hepdata.22184

Measurements of the ratio of Drell-Yan yields from an 800 \rm{GeV/c} proton beam incident on liquid hydrogen and deuterium targets are reported. Approximately 360,000 Drell-Yan muon pairs remained after all cuts on the data. From these data, the ratio of anti-down ($\bar{d}$) to anti-up ($\bar{u}$) quark distributions in the proton sea is determined over a wide range in Bjorken-$x$. These results confirm previous measurements by E866 and extend them to lower $x$. From these data, $(\bar{d}-\bar{u})$ and $\int(\bar{d}-\bar{u})dx$ are evaluated for $0.015&lt;x&lt;0.35$. These results are compared with parameterizations of various parton distribution functions, models and experimental results from NA51, NMC, and HERMES.

4 data tables

Cross section ratio for the high mass data set. Additional systematic error is 0.97 PCT for this data set.

Cross section ratio for the intermediate mass data set. Additional systematic error is 0.94 PCT for this data set.

Cross section ratio for the low mass data set. Additional systematic error is 0.87 PCT for this data set.

More…

Nuclear dependence of dimuon production at 800-GeV. FNAL-772 experiment

Alde, D.M. ; Baer, H.W. ; Carey, T.A. ; et al.
Phys.Rev.Lett. 64 (1990) 2479-2482, 1990.
Inspire Record 303588 DOI 10.17182/hepdata.19997
10 data tables

High Mass trigger data.

Intermediate Mass trigger data.

Low Mass trigger data.

More…

Dimuon Scaling Comparison at 44-{GeV} and 62-{GeV}

Antreasyan, D. ; Becker, U. ; Bellettini, G. ; et al.
Phys.Rev.Lett. 48 (1982) 302, 1982.
Inspire Record 168182 DOI 10.17182/hepdata.20610
1 data table

No description provided.