Probing the heavy quark content of the photon using<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>b</mml:mi></mml:math>tagging at high energy<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>e</mml:mi><mml:mi>γ</mml:mi></mml:math>and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow><mml:mi>e</mml:mi></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:mrow><mml:mrow><mml:ms

Doncheski, M. A.; Godfrey, Stephen; Peterson, K. Andrew

doi:10.1103/physrevd.55.183

Cited by 5 publications

(2 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is well known that this process is promising for probing the structure of the photon, see e.g. [6,7] and [8], where a related topic is considered. Heavy quarks can be produced in γγ collisions through three mechanisms.…”

Section: In High Energy Ementioning

confidence: 99%

Heavy quark production at the TESLA collider and its sensitivity to the gluon content in the photon

2002

View full text Add to dashboard Cite

Heavy quark production is studied at the high energy linear e + e − collider (LC) TESLA both in its nominal and Photon Collider (PC) mode. Leading order cross-sections are calculated for the production of heavy quarks, e + e − → e + e − Q(Q)X, at high transverse momenta. The sensitivity of this process to the gluon content in the photon is studied. An e+ e − linear collider with a centre of mass system (CMS) energy in the range of 500 to 1000 GeV is the prime candidate for the next high energy accelerator project after the LHC. Recently TESLA [1] has completed a Technical Design Report for such a collider. For the study of a future electron-positron Linear Collider (LC) it is important to examine the physics potential of its main and possible additional options. Such an option is the Photon (or Compton) Collider (PC) in which high energy real photons can be obtained by backscattering photons from a laser beam on the electron or positron beam [2,3]. This way an excellent tool for the study of γγ collisions at high energies can be provided. In high energy e+ e − collisions the hadronic final state is predominantly produced in γ γ interactions where the virtual photons (γ ) are almost on mass shell. Their scattering can be effectively described with the interaction of real photons with energy spectra given by the Weizsäcker-Williams (WW) approximation [4]. Such a spectrum is generally quite soft, as shown in Fig. 1. In contrast, a Photon Collider, based on Compton scattering, provides beams of real photons which are much harder than those from a WW distribution (see Fig. 1). Furthermore these photons can be produced 1 in a definite polarization state. While the energy spectrum of the PC at the high energy end can be well calculated based on a few parameters of the laser and incident electron beam, the lower energy end depends much more on the details of machine and operation. Therefore we limit ourself to study only the high energy peak of 0.6 < y = E γ /E e < 0.83 [5]. The spectra used in this paper are described in the Appendix.The main goal of this study is to compare the LC and PC potential for probing the gluon distribution in the photon via heavy quark production. This analysis does not make use of polarization. The measurement of the process e + e − → e + e − Q(Q)X is an important test of QCD. It is well known that this process is promising for probing the structure of the photon, see e.g. [6,7] and [8], where a related topic is considered. Heavy quarks can be produced in γγ collisions through three mechanisms. Direct (DD) production occurs when both photons couple directly to a QQ pair. In single resolved photoproduction processes (DR) one of photons interacts via its partons with the second photon. When both photons split into a flux of quarks and gluons, the process is labelled a double resolved photon (RR) process.There are various schemes proposed for calculating cross-sections for processes involving heavy quarks, for the latest overview see ref [9]. Two standard schemes will be used in this a...

show abstract

Section: In High Energy Ementioning

confidence: 99%

Heavy quark production at the TESLA collider and its sensitivity to the gluon content in the photon

2002

View full text Add to dashboard Cite

show abstract

“…Heavy quark production in the unpolarized electron-positron scattering e + e − → e + e − Q(Q)X is a promising process for such a study, see e.g. [3,4] and also [5], where the related topic is considered. The measurement of this process is also an important test of QCD by itself.…”

mentioning

confidence: 99%

Charm production at a linear e+e− and photon collider and its sensitivity to the gluon content of the photon

Jankowski¹,

Krawczyk²,

Roeck³

2001

Nuclear Instruments and Methods in Physics Research Section A:

View full text Add to dashboard Cite

A high energy linear e + e − collider (LC) can also be used as a Photon Collider (PC), using Compton scattering of laser photons on the e + /e − beams. The leading order cross-section for the production of heavy quarks, e + e − → e + e − Q(Q)X, at high transverse momenta is calculated for both LC and PC modes. The sensitivity of this process to the parton distribution parametrizations of real photons, especially the gluon content, is tested for both modes.For the study of a future electron-positron Linear Collider (LC) it is important to examine the physics potential for its main and possible derived options. The so called Photon (or Compton) Collider (PC) is an option in which high energy real photons can be obtained by backscattering photons from a laser beam on the electron or positron beam [1,2]. This way an excellent tool for the study of γγ collisions at high energies can be constructed.In high energy e + e − collisions the hadronic final state is predominantly produced in γ ⋆ γ ⋆ interactions where the virtual photons are almost on mass shell. These processes can be described by an effective (real) photon energy spectrum, i.e. using the Weizsäcker-Williams (WW) approximation. A Photon Collider based on Compton scattering, however, provides beams of real photons, which can be produced in a definite polarization state and with high monochromaticity. Moreover, the resulting photon spectrum (denoted as LASER) is much harder then the WW one. The comparison of the photon spectra used in this analysis (see Appendix) is presented in Fig. 1.The main goal of this work is to compare the LC and PC opportunities for probing the gluon distribution in the photon, without making use of polarization. Heavy quark 1

show abstract

Measurement of theWWγcoupling in the processeγ→νqq
Doncheski
¹
,
Godfrey
²
,
Peterson
³

1999
Phys. Rev. D
4
0
18
0
View full text Add to dashboard Cite

We study the WW␥ gauge boson coupling in the process e␥→qq off the W-boson resonance by evaluating the helicity amplitudes of all contributing Feynman diagrams. We examine this process for 500 GeV and 1 TeV e ϩ e Ϫ colliders including the photon spectra obtained from both a backscattered laser and from beamstrahlung radiation. The couplings could best be measured using the backscattered laser photons with ͉␦ ␥ ͉ р0.08 and Ϫ0.07Ͻ ␥ Ͻ0.10 at a 500 GeV collider and ͉ ␥ ͉р0.03 at a 1 TeV collider, all at 95% C.L. Except for the relatively weak limits on ␦ at ͱsϭ1 TeV, these sensitivities are the same order of magnitude as can be obtained from real single W-production demonstrating that additional information can be obtained from non-resonant final states. ͓S0556-2821͑99͒01811-1͔ PACS number͑s͒: 12.15.Ji, 12.60.Cn, 14.70.Fm versity, Halifax, NS, Canada B3H 4J1.

show abstract

Probing the heavy quark content of the photon usingbtagging at high energyeγande+

Cited by 5 publications

References 29 publications

Heavy quark production at the TESLA collider and its sensitivity to the gluon content in the photon

Heavy quark production at the TESLA collider and its sensitivity to the gluon content in the photon

Charm production at a linear e+e− and photon collider and its sensitivity to the gluon content of the photon

Measurement of theWWγcoupling in the processeγ→νqq
Doncheski
¹
,
Godfrey
²
,
Peterson
³

1999
Phys. Rev. D
4
0
18
0
View full text Add to dashboard Cite

Contact Info

Product

Resources

About

Probing the heavy quark content of the photon usingbtagging at high energyeγande+

Cited by 5 publications

References 29 publications

Heavy quark production at the TESLA collider and its sensitivity to the gluon content in the photon

Heavy quark production at the TESLA collider and its sensitivity to the gluon content in the photon

Charm production at a linear e+e− and photon collider and its sensitivity to the gluon content of the photon

Measurement of theWWγcoupling in the processeγ→νqqDoncheski1, Godfrey2, Peterson3 1999Phys. Rev. D40180View full textAdd to dashboardCite

Contact Info

Product

Resources

About

Measurement of theWWγcoupling in the processeγ→νqq
Doncheski
¹
,
Godfrey
²
,
Peterson
³

1999
Phys. Rev. D
4
0
18
0
View full text Add to dashboard Cite