The challenges of beam polarization and keV-scale centre-of-mass energy calibration at the FCC-ee

AbstractThe capability to determine the FCC-ee centre-of-mass energies (ECM) at the ppm level using resonant depolarization of the beams is essential for the Z line shape measurements, the W mass and the possible observation of the Higgs boson s-channel production. A first analysis (Blondel A et al Polarization and centre-of-mass energy calibration at FCC-ee. arXiv:1909.12245) demonstrated the feasibility of this programme, conditional to careful preparation and a number of further developments. The existing simulation codes must be unified; the analysis and design of the instrumentation must be developed; and a detailed planning must be developed for the simultaneous and coordinated operation of the accelerator, of the continuous polarization and depolarization measurements, and of the beam monitoring devices, ensuring a precise extrapolation from beam energies to centre-of-mass energy and energy spread.

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Measurements of the Higgs H(125) boson at CMS

EPJ Web of Conferences ◽

10.1051/epjconf/201818202018 ◽

2018 ◽

Vol 182 ◽

pp. 02018

Author(s):

Valeria Botta

Keyword(s):

Higgs Boson ◽

Large Hadron Collider ◽

Hadron Collider ◽

Top Quarks ◽

Final States ◽

Centre Of Mass ◽

Mass Energy ◽

Associated Production ◽

Cms Detector ◽

Integrated Luminosity

The most recent measurements of the Higgs H(125) boson in several final states, including decays to bosons, fermions, and the associated production of a Higgs boson with top quarks, are reviewed. Results have been obtained analysing the protonproton collision data collected with the CMS detector at the Large Hadron Collider (LHC) in 2016, corresponding to an integrated luminosity of 35.9 fb-1 at a centre-of-mass energy of 13 TeV.

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Highlights from ATLAS

EPJ Web of Conferences ◽

10.1051/epjconf/201818202012 ◽

2018 ◽

Vol 182 ◽

pp. 02012

Author(s):

L. Bellagamba

Keyword(s):

Higgs Boson ◽

Standard Model ◽

Heavy Ion Collisions ◽

Heavy Ion ◽

New Physics ◽

Atlas Collaboration ◽

Centre Of Mass ◽

Mass Energy ◽

Pp Collisions ◽

Ion Collisions

This report presents an overview of some of the most recent results obtained by the ATLAS Collaboration using pp and heavy-ion collisions at the LHC. The review is not intended to be comprehensive and includes recent updates on the Higgs boson properties, precision Standard Model measurements, as well as searches for new physics. Most of the results exploit the data collected in the last LHC run, providing pp collisions at a centre of mass energy of 13 TeV.

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Measurement of cross sections and couplings of the Higgs Boson in bosonic decay channels with the ATLAS detector

EPJ Web of Conferences ◽

10.1051/epjconf/201818202013 ◽

2018 ◽

Vol 182 ◽

pp. 02013

Author(s):

Nikita Belyaev

Keyword(s):

Higgs Boson ◽

Cross Sections ◽

Hadron Collider ◽

Atlas Detector ◽

Atlas Collaboration ◽

Standard Model Higgs Boson ◽

Centre Of Mass ◽

Mass Energy ◽

Decay Channels ◽

The Standard Model

After the discovery of the Higgs boson, the measurement of its properties are of particular importance. In this paper, measurement of the cross sections and couplings of the Higgs boson in bosonic decay channels with the ATLAS detector are presented. Previous measurements of the spin and parity of this new particle, as well as the investigation of its couplings to other SM particles, revealed no significant deviations from the corresponding predictions for the Standard Model Higgs boson. In the years 2015-2017, the centre-of-mass energy √s and the integrated luminosity of the Large Hadron Collider was increased up to 13 TeV and 36.1 fb-1, respectively. With this improvements of the LHC, the properties of recently discovered Higgs boson can be studied in more details. In this paper, latest updates on cross sections and couplings analyses of the Higgs Boson are presented. The discussion will focus on the recent results obtained by the ATLAS collaboration in γγ and 4l Higgs boson decay channels as well as their combination.

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Constraining capability of Zγh production at the ILC

International Journal of Modern Physics A ◽

10.1142/s0217751x17500178 ◽

2017 ◽

Vol 32 (02n03) ◽

pp. 1750017

Author(s):

Sher Alam ◽

Subhasish Behera ◽

Satendra Kumar ◽

Shibananda Sahoo

Keyword(s):

Higgs Boson ◽

Center Of Mass ◽

Beam Polarization ◽

Mass Energy ◽

Gauge Bosons ◽

Center Of Mass Energy ◽

Lagrangian Framework ◽

Effective Lagrangian ◽

Coupling Parameters

Higgs boson couplings with gauge bosons are probed through [Formula: see text] in an effective Lagrangian framework. For this study, the beam polarization facility at the ILC along with the typical center-of-mass energy of 500 GeV is considered. The reach of the ILC with an integrated luminosity of 300 fb[Formula: see text] in the determination of CP-conserving parameters is obtained. Sensitivity of the probe of each of these couplings in the presence of other couplings is investigated. The most influential coupling parameters are [Formula: see text]. Other parameters of significant effect are [Formula: see text] and [Formula: see text]. A detailed study of the various kinematic distributions represents possibilities to disentangle the effect of some of these couplings.

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Measuring the quartic Higgs self-coupling at a multi-TeV muon collider

Journal of High Energy Physics ◽

10.1007/jhep09(2020)098 ◽

2020 ◽

Vol 2020 (9) ◽

Cited By ~ 1

Author(s):

M. Chiesa ◽

F. Maltoni ◽

L. Mantani ◽

B. Mele ◽

F. Piccinini ◽

...

Keyword(s):

Higgs Boson ◽

Center Of Mass ◽

Mass Energy ◽

Simple Analysis ◽

Proton Proton ◽

Coupling Interaction ◽

Center Of Mass Energy ◽

Muon Collider ◽

Better Than

Abstract Measuring the shape of the Higgs boson potential is of paramount importance, and will be a challenging task at current as well as future colliders. While the expectations for the measurement of the trilinear Higgs self-coupling are rather promising, an accurate measurement of the quartic self-coupling interaction is presently considered extremely challenging even at a future 100 TeV proton-proton collider. In this work we explore the sensitivity that a muon collider with a center of mass energy in the multi-TeV range and luminosities of the order of 1035cm−2s−1, as presently under discussion, might provide, thanks to a rather large three Higgs-boson production and to a limited background. By performing a first and simple analysis, we find a clear indication that a muon collider could provide a determination of the quartic Higgs self-coupling that is significantly better than what is currently considered attainable at other future colliders.

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Measurement of the shape of the $$ {B}_s^0\to {D}_s^{\ast -}{\mu}^{+}{\nu}_{\mu } $$ differential decay rate

Journal of High Energy Physics ◽

10.1007/jhep12(2020)144 ◽

2020 ◽

Vol 2020 (12) ◽

Author(s):

R. Aaij ◽

◽

C. Abellán Beteta ◽

T. Ackernley ◽

B. Adeva ◽

...

Keyword(s):

Decay Rate ◽

Form Factors ◽

Proton Collision ◽

Centre Of Mass ◽

Mass Energy ◽

Proton Proton ◽

Lhcb Detector ◽

Proton Proton Collision ◽

Integrated Luminosity

Abstract The shape of the $$ {B}_s^0\to {D}_s^{\ast -}{\mu}^{+}{\nu}_{\mu } $$ B s 0 → D s ∗ − μ + ν μ differential decay rate is obtained as a function of the hadron recoil parameter using proton-proton collision data at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 1.7 fb−1 collected by the LHCb detector. The $$ {B}_s^0\to {D}_s^{\ast -}{\mu}^{+}{\nu}_{\mu } $$ B s 0 → D s ∗ − μ + ν μ decay is reconstructed through the decays $$ {D}_s^{\ast -}\to {D}_s^{-}\gamma $$ D s ∗ − → D s − γ and $$ {D}_s^{-}\to {K}^{-}{K}^{+}{\pi}^{-} $$ D s − → K − K + π − . The differential decay rate is fitted with the Caprini-Lellouch-Neubert (CLN) and Boyd-Grinstein-Lebed (BGL) parametrisations of the form factors, and the relevant quantities for both are extracted.

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