scholarly journals Search for direct production of electroweakinos in final states with missing transverse momentum and a Higgs boson decaying into photons in pp collisions at $$ \sqrt{s} $$ = 13 TeV with the ATLAS detector

2020 ◽  
Vol 2020 (10) ◽  
Author(s):  
G. Aad ◽  
◽  
B. Abbott ◽  
D. C. Abbott ◽  
A. Abed Abud ◽  
...  
Keyword(s):  
Higgs Boson ◽  
Cross Section ◽  
Cross Sections ◽  
Confidence Level ◽  
Production Cross ◽  
Atlas Detector ◽  
Supersymmetric Particle ◽  
Direct Production ◽  
Missing Transverse Momentum ◽  
Upper Limits

Abstract A search for a chargino-neutralino pair decaying via the 125 GeV Higgs boson into photons is presented. The study is based on the data collected between 2015 and 2018 with the ATLAS detector at the LHC, corresponding to an integrated luminosity of 139 fb−1 of pp collisions at a centre-of-mass energy of 13 TeV. No significant excess over the expected background is observed. Upper limits at 95% confidence level for a massless $$ {\tilde{\chi}}_1^0 $$ χ ˜ 1 0 are set on several electroweakino production cross-sections and the visible cross-section for beyond the Standard Model processes. In the context of simplified supersymmetric models, 95% confidence-level limits of up to 310 GeV in $$ m\left({\tilde{\chi}}_1^{\pm }/{\tilde{\chi}}_2^0\right) $$ m χ ˜ 1 ± / χ ˜ 2 0 , where $$ m\left({\tilde{\chi}}_1^0\right) $$ m χ ˜ 1 0 = 0.5 GeV, are set. Limits at 95% confidence level are also set on the $$ {\tilde{\chi}}_1^{\pm }{\tilde{\chi}}_2^0 $$ χ ˜ 1 ± χ ˜ 2 0 cross-section in the mass plane of $$ m\left({\tilde{\chi}}_1^{\pm }/{\tilde{\chi}}_2^0\right) $$ m χ ˜ 1 ± / χ ˜ 2 0 and $$ m\left({\tilde{\chi}}_1^0\right) $$ m χ ˜ 1 0 , and on scenarios with gravitino as the lightest supersymmetric particle. Upper limits at the 95% confidence-level are set on the higgsino production cross-section. Higgsino masses below 380 GeV are excluded for the case of the higgsino fully decaying into a Higgs boson and a gravitino.

scholarly journals Search for direct production of electroweakinos in final states with one lepton, missing transverse momentum and a Higgs boson decaying into two b-jets in $$pp$$ collisions at $$\sqrt{s}=13$$ TeV with the ATLAS detector

2020 ◽  
Vol 80 (8) ◽  
Author(s):  
G. Aad ◽  
◽  
B. Abbott ◽  
D. C. Abbott ◽  
A. Abed Abud ◽  
...  
Keyword(s):  
Higgs Boson ◽  
Transverse Momentum ◽  
Standard Model ◽  
Cross Sections ◽  
Hadron Collider ◽  
Atlas Detector ◽  
Direct Production ◽  
Missing Transverse Momentum ◽  
Higgs Boson Decaying ◽  
The Standard Model

Abstract The results of a search for electroweakino pair production $$pp \rightarrow \tilde{\chi }^\pm _1 \tilde{\chi }^0_2$$pp→χ~1±χ~20 in which the chargino ($$\tilde{\chi }^\pm _1$$χ~1±) decays into a W boson and the lightest neutralino ($$\tilde{\chi }^0_1$$χ~10), while the heavier neutralino ($$\tilde{\chi }^0_2$$χ~20) decays into the Standard Model 125 GeV Higgs boson and a second $$\tilde{\chi }^0_1$$χ~10 are presented. The signal selection requires a pair of b-tagged jets consistent with those from a Higgs boson decay, and either an electron or a muon from the W boson decay, together with missing transverse momentum from the corresponding neutrino and the stable neutralinos. The analysis is based on data corresponding to 139 $$\mathrm {fb}^{-1}$$fb-1 of $$\sqrt{s}=13$$s=13 TeV pp collisions provided by the Large Hadron Collider and recorded by the ATLAS detector. No statistically significant evidence of an excess of events above the Standard Model expectation is found. Limits are set on the direct production of the electroweakinos in simplified models, assuming pure wino cross-sections. Masses of $$\tilde{\chi }^{\pm }_{1}/\tilde{\chi }^{0}_{2}$$χ~1±/χ~20 up to 740 GeV are excluded at 95% confidence level for a massless $$\tilde{\chi }^{0}_{1}$$χ~10.

scholarly journals Erratum to: Higgs boson production cross-section measurements and their EFT interpretation in the $$4\ell $$ decay channel at $$\sqrt{s}=$$13 TeV with the ATLAS detector

2021 ◽  
Vol 81 (5) ◽  
Author(s):  
G. Aad ◽  
◽  
B. Abbott ◽  
D. C. Abbott ◽  
A. Abed Abud ◽  
...  
Keyword(s):  
Higgs Boson ◽  
Cross Section ◽  
Production Cross Section ◽  
Decay Channel ◽  
Production Cross ◽  
Atlas Detector ◽  
Boson Production ◽  
Higgs Boson Production

A Correction to this paper has been published: https://doi.org/10.1140/epjc/s10052-020-8227-9

TRIPLE GAUGE BOSON PRODUCTION IN e+e- COLLISIONS

1991 ◽  
Vol 06 (39) ◽  
pp. 3565-3572
Author(s):  
M. H. NOUS ◽  
M. El-KISHEN ◽  
A. M. ALGELANI
Keyword(s):  
Higgs Boson ◽  
Standard Model ◽  
Supersymmetric Standard Model ◽  
Cross Section ◽  
Gauge Boson ◽  
Cross Sections ◽  
Production Cross ◽  
Boson Production ◽  
Production Mechanism ◽  
The Standard Model

The production cross-sections for a triple gauge boson has been investigated in both the standard model and the minimal supersymmetric standard model, via e+e-→W+W-Z0. All events that contain the Higgs-boson seem to have no influence in this process. At [Formula: see text], this process could be detected with a reasonable cross-section, the production mechanism in this case will be e+e-→Z0→W+W-→W+W-Z0.

scholarly journals Improved $$(g-2)_\mu $$ measurements and supersymmetry

2020 ◽  
Vol 80 (10) ◽  
Author(s):  
Manimala Chakraborti ◽  
Sven Heinemeyer ◽  
Ipsita Saha
Keyword(s):  
Experimental Data ◽  
Standard Model ◽  
Cross Sections ◽  
Direct Detection ◽  
Production Cross ◽  
High Energy ◽  
Experimental Result ◽  
Supersymmetric Particle ◽  
Negative Results ◽  
Upper Limits

AbstractThe electroweak (EW) sector of the Minimal Supersymmetric Standard Model (MSSM) can account for variety of experimental data. The lighest supersymmetric particle (LSP), which we take as the lightest neutralino, $${\tilde{\chi }}_{1}^0$$ χ ~ 1 0 , can account for the observed Dark Matter (DM) content of the universe via coannihilation with the next-to-LSP (NLSP), while being in agreement with negative results from Direct Detection (DD) experiments. Owing to relatively small production cross-sections a comparably light EW sector of the MSSM is also in agreement with the unsuccessful searches at the LHC. Most importantly, the EW sector of the MSSM can account for the persistent $$3-4\,\sigma $$ 3 - 4 σ discrepancy between the experimental result for the anomalous magnetic moment of the muon, $$(g-2)_\mu $$ ( g - 2 ) μ , and its Standard Model (SM) prediction. Under the assumption that the $${\tilde{\chi }}_{1}^0$$ χ ~ 1 0 provides the full DM relic abundance we first analyze which mass ranges of neutralinos, charginos and scalar leptons are in agreement with all experimental data, including relevant LHC searches. We find an upper limit of $$\sim 600 \,\, \mathrm {GeV}$$ ∼ 600 GeV for the LSP and NLSP masses. In a second step we assume that the new result of the Run 1 of the “MUON G-2” collaboration at Fermilab yields a precision comparable to the existing experimental result with the same central value. We analyze the potential impact of the combination of the Run 1 data with the existing $$(g-2)_\mu $$ ( g - 2 ) μ data on the allowed MSSM parameter space. We find that in this case the upper limits on the LSP and NLSP masses are substantially reduced by roughly $$100 \,\, \mathrm {GeV}$$ 100 GeV . This would yield improved upper limits on these masses of $$\sim 500 \,\, \mathrm {GeV}$$ ∼ 500 GeV . In this way, a clear target could be set for future LHC EW searches, as well as for future high-energy $$e^+e^-$$ e + e -  colliders, such as the ILC or CLIC.

scholarly journals Measurements of production cross sections of the Higgs boson in the four-lepton final state in proton–proton collisions at $$\sqrt{s} = 13\,\text {Te}\text {V} $$

2021 ◽  
Vol 81 (6) ◽  
Author(s):  
A. M. Sirunyan ◽  
A. Tumasyan ◽  
W. Adam ◽  
J. W. Andrejkovic ◽  
T. Bergauer ◽  
...  
Keyword(s):  
Higgs Boson ◽  
Transverse Momentum ◽  
Cross Section ◽  
Cross Sections ◽  
Production Cross ◽  
Signal Strength ◽  
Boson Production ◽  
Proton Proton ◽  
Proton Collisions ◽  
Proton Proton Collisions

AbstractProduction cross sections of the Higgs boson are measured in the $${\mathrm{H}} \rightarrow {\mathrm{Z}} {\mathrm{Z}} \rightarrow 4\ell $$ H → Z Z → 4 ℓ ($$\ell ={\mathrm{e}},{{{\upmu }}_{\mathrm{}}^{\mathrm{}}} $$ ℓ = e , μ ) decay channel. A data sample of proton–proton collisions at a center-of-mass energy of 13$$\,\text {Te}\text {V}$$ Te , collected by the CMS detector at the LHC and corresponding to an integrated luminosity of 137$$\,\text {fb}^{-1}$$ fb - 1 is used. The signal strength modifier $$\mu $$ μ , defined as the ratio of the Higgs boson production rate in the $$4\ell $$ 4 ℓ channel to the standard model (SM) expectation, is measured to be $$\mu =0.94 \pm 0.07 \,\text {(stat)} ^{+0.09}_{-0.08} \,\text {(syst)} $$ μ = 0.94 ± 0.07 (stat) - 0.08 + 0.09 (syst) at a fixed value of $$m_{{\mathrm{H}}} = 125.38\,\text {Ge}\text {V} $$ m H = 125.38 Ge . The signal strength modifiers for the individual Higgs boson production modes are also reported. The inclusive fiducial cross section for the $${\mathrm{H}} \rightarrow 4\ell $$ H → 4 ℓ process is measured to be $$2.84^{+0.23}_{-0.22} \,\text {(stat)} ^{+0.26}_{-0.21} \,\text {(syst)} \,\text {fb} $$ 2 . 84 - 0.22 + 0.23 (stat) - 0.21 + 0.26 (syst) fb , which is compatible with the SM prediction of $$2.84 \pm 0.15 \,\text {fb} $$ 2.84 ± 0.15 fb for the same fiducial region. Differential cross sections as a function of the transverse momentum and rapidity of the Higgs boson, the number of associated jets, and the transverse momentum of the leading associated jet are measured. A new set of cross section measurements in mutually exclusive categories targeted to identify production mechanisms and kinematical features of the events is presented. The results are in agreement with the SM predictions.

A SEARCH FOR HIGGS DECAYS TO WW* AT DØ

2005 ◽  
Vol 20 (15) ◽  
pp. 3297-3301
Author(s):  
◽  
AMBER JENKINS
Keyword(s):  
Higgs Boson ◽  
Cross Section ◽  
Confidence Level ◽  
Production Cross Section ◽  
Production Cross ◽  
Branching Ratio ◽  
Final States ◽  
Theoretical Predictions ◽  
Integrated Luminosity

A search for the Higgs boson in the channels [Formula: see text] at DØ is described. The data, corresponding to an integrated luminosity of up to 177 pb-1, are compared to theoretical predictions. No excess of events above the expected background is observed in any of the leptonic final states. Limits on the production cross-section times branching ratio, σ × BR(H → WW*), are therefore set at the 95% Confidence Level.

scholarly journals Comparing production cross-sections for QCD matter, Higgs boson, neutrino with dark energy in accelerating universe

2017 ◽  
Vol 14 (10) ◽  
pp. 1750139 ◽  
Author(s):  
Tooraj Ghaffary
Keyword(s):  
Dark Energy ◽  
Higgs Boson ◽  
Event Horizon ◽  
Cross Section ◽  
Cross Sections ◽  
Production Cross Section ◽  
Production Cross ◽  
Higgs Bosons ◽  
Accelerating Universe ◽  
The Universe

In this research, the production cross-sections for quantum chromodynamics (QCD) matter, neutrino and dark energy due to acceleration of Universe are calculated. To obtain these cross-sections, the Universe production cross-section is multiplied by the particle or dark energy distribution in accelerating Universe. Also, missing cross-section for each matter and dark energy due to formation of event horizon is calculated. It is clear that the cross-section of particles produced near event horizon of Universe is much larger for higher acceleration of Universe. This is because as the acceleration of Universe becomes larger, the Unruh temperature becomes larger and the thermal radiations of particles are enhanced. There are different channels for producing Higgs boson in accelerating Universe. Universe may decay to quark and gluons, and then these particles interact with each other and Higgs boson is produced. Also, some Higgs bosons are emitted directly from event horizon of Universe. Comparing Higgs boson cross-sections via different channels, it is observed that at lower acceleration, [Formula: see text], the Universe will not be able to emit Higgs, but is still able to produce a quark and eventually for [Formula: see text] the Universe can only emit massless gluons. As the acceleration of Universe at the large hadron collider (LHC) increases, [Formula: see text], most of Higgs bosons production will be due to Unruh effect near event horizon of Universe. Finally comparing the production cross-section for dark energy with particle cross-sections, it is found that the cross-section for dark energy is dominated by QCD matter, Higgs boson and neutrino. This result is consistent with previous predictions for dark energy cross-section.

Sign in / Sign up

Export Citation Format

Share Document