胶子融合对强子对撞机VHj生产的贡献资源-CSDN文库

Open

Access

187 浏览量 2020-04-04 18:11:14 上传评论收藏 404KB PDF 举报

资源推荐

资源详情

资源评论

Physics Letters B 741 (2015) 111–116

Contents lists available at ScienceDirect

Physics Letters B

www.elsevier.com/locate/physletb

Gluon fusion contribution to VHj production at hadron colliders

Pankaj Agrawal

, Ambresh Shivaji

b,∗

Institute of Physics, Sachivalaya Marg, Bhubaneswar, Odisha 751005, India

Regional Centre for Accelerator-based Particle Physics, Harish-Chandra Research Institute, Chhatnag Road, Jhusi, Allahabad 211019, India

a r t i c l e i n f o a b s t r a c t

Article history:

Received

30 September 2014

Received

in revised form 2 December 2014

Accepted

8 December 2014

Available

online 12 December 2014

Editor:

G.F. Giudice

Keywords:

LHC

Gluon

fusion

Higgs

One-loop

We study the associated production of an electroweak vector boson and the Higgs boson with a jet

via gluon–gluon fusion. At the leading order, these processes occur at one-loop level. The amplitudes

of these one-loop processes are gauge invariant and ﬁnite. Therefore, their contributions towards the

corresponding hadronic cross sections and kinematic distributions can be calculated separately. We

present results for the Large Hadron Collider and its discussed upgrades. We ﬁnd that the gluon–

gluon

one-loop process gives dominant contribution to the γ Hj production. We observe a destructive

interference effect in the gg → ZHj amplitude. We also ﬁnd that in the high transverse momentum and

central rapidity region, the ZHj production cross section via gluon–gluon fusion becomes comparable to

the cross section contributions coming from quark–quark and quark–gluon channels.

(http://creativecommons.org/licenses/by/3.0/). Funded by SCOAP

With the discovery of the Higgs boson [1,2] at the Large Hadron

Collider (LHC), the standard model and its symmetry-breaking

mechanism have been validated. The CMS and ATLAS Collabora-

tions are

measuring its properties.The Higgs boson was discov-

ered

through gg → H production mechanism. Since then signals

of other production mechanisms have also been examined. In par-

ticular,

the associated production of the Higgs boson with an elec-

troweak

boson has been explored [3,4]. To ensure that the discov-

ered

Higgs boson is indeed the standard model Higgs boson, there

is a need to detect as many of its signatures as possible. Further-

more,

since there is no signal that points to new physics beyond

the standard model, there is a need to look for standard model

processes that do not have large but accessible cross sections, and

can be enhanced/modiﬁed by new physics effects.

The

LHC and its proposed upgrades provide us an opportunity

to explore two types of processes in more detail: (a) the pro-

cesses

which, in the standard model, begin at the one-loop level

(one-loop being the leading order (LO)); (b) gluon–gluon scatter-

ing

processes. As the centre-of-mass energy increases, the gluon–

gluon

luminosity increases, making many more processes observ-

able.

Study of such relatively rare processes is complementary to

new physics searches at high energy colliders. Thus, the LHC pro-

vides

a unique opportunity for testing many of the standard model

predictions which was not possible at earlier high energy colliders.

Corresponding author.

E-mail

addresses: agrawal@iopb.res.in (P. Agrawal), ambreshkshivaji@hri.res.in

(A. Shivaji).

For example, many one-loop gluon–gluon fusion processes are/will

be accessible only at the LHC [5–10]. These gluon fusion one-loop

processes can be studied both in the signal and background cate-

gories.

this Letter, we are interested in the gluon–gluon contribution

to the pp → VHj + X hadronic processes, i.e.,

g + g → VHj, (1)

where V is an electroweak vector boson and ‘ j’ stands for a

light-quark, or gluon initiated jet. The amplitude of the process

gg → W

Hj is trivially zero due to the electromagnetic charge

conservation. Therefore, V would refer to a photon or a Z boson.

This process occurs at the one-loop via triangle, box, and pen-

tagon

diagrams. Since quarks carry both the electroweak and color

charges, the leading order contribution comes from quark-loop dia-

grams.

The prototype quark-loop diagrams are shown in Fig. 1 [11].

(We have not displayed some of the triangle and bubble diagrams

which do not contribute due to the vanishing color factor.) For the

γ Hj case, only pentagon class of diagrams contribute. The box dia-

grams

with qqH coupling do not contribute because of the Furry’s

theorem. Due to the same reason, the leading order gg → γ H am-

plitude

vanishes. There are a total 24 pentagon diagrams. However,

due to charge conjugation symmetry only 12 of those are inde-

pendent.

The full amplitude is proportional to the symmetric color

factor d

abc

the ZHj case, box and triangle diagrams also contribute.

Once again there are 12 independent pentagon (PEN) diagrams.

There are two types of box diagrams depending on the nature of

http://dx.doi.org/10.1016/j.physletb.2014.12.021

0370-2693/

SCOAP

本内容试读结束，登录后可阅读更多

下载后可阅读完整内容，剩余5页未读，立即下载

评论收藏

内容反馈

weixin_38524139

粉丝: 7
资源: 916

胶子融合对强子对撞机VHj生产的贡献

用ATLAS探测器在碰撞的→→衰减通道中测量胶子-胶子融合和矢量-玻色子融合希格斯玻色子产生截面

大型强子对撞机重油生产中的胶子阴影

强子对撞机通过胶子聚变生产希格斯对：NLO QCD校正

大型强子对撞机的Kaluza–Klein胶子+喷气机相关生产

大型强子对撞机胶子融合希格斯玻色子截面的高精度测定

大型强子对撞机的hhjj生产

大型强子对撞机可能通过重的希格斯玻色子衰变发现潜在的成因

NNLO QCD中强子对撞机的ZZ生产

在大型强子对撞机上约束异常胶子自我相互作用：重新评估

大型强子对撞机的ZZ产生：回路诱导的胶子融合通道的NLO QCD校正

更正为：“在大型强子对撞机中使用石英对生产，固定非极化质子内部的线性极化胶子”。 来吧 B 784（2018）217]

汤河川对大型强子对撞机生产bbH的贡献

解决当前和未来强子对撞机的胶子聚变回路

违反轻子风味的胶子运算符：大型强子对撞机和低能实验的限制

NLO QCD和顶级质谱方案将胶子融合成希格斯对

大型强子对撞机在tt¯W±生成中的顶夸克电荷不对称和极化

QCD NNLO的强子对撞机上的三希格斯产量

强子对撞机产生HHH和HHV（V =γ，Z）

大型强子对撞机在双波默龙交换事件中迅速产生光子

大型强子对撞机的Z玻色子加上喷气机生产的高阶校正的恢复

在大型强子对撞机中停止对生产的NNLL恢复

大型强子对撞机S通道单顶夸克生产的横向动量恢复

大型强子对撞机中Pb-Pb碰撞中夸克对J /ψ产生的强烈扩散作用

大型强子对撞机生产中的动量空间阈值恢复

大型强子对撞机最小耦合的dilaton和多轻子特征的共形尺度界

大型强子对撞机t通道单顶夸克生产的横向动量恢复

最新资源

更正为：“在大型强子对撞机中使用石英对生产，固定非极化质子内部的线性极化胶子”。来吧 B 784（2018）217]