Three heavy jet events at hadron colliders as a sensitive probe of the Higgs sector
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2024届北京市西城区高三二模语文试题(答案在最后)2024.5本试卷共10页,共150分。
考试时长150分钟。
考生务必将答案写在答题卡上,在试卷上作答无效。
一、本大题共5小题,共18分。
阅读下面材料,完成小题。
材料一2023年是人工智能领域爆炸式发展的一年,OpenAI公司推出的ChatGPT便是其中的代表。
一年多的时间里,ChatGPT的版本从3.5升级到4.0,进步明显:专门训练它的硬件设备升级,其中央处理器(CPU)内核和专用图形处理器(GPU)分别增加到28万个和1万个;它有1万亿个参数,知识的获取从检索固定的数据库发展到可以自行上网寻找资料;它不但可以解读用户发送的图片,还可以根据文字描述生成图像……人工智能产品研发领域的竞争非常激烈。
ChatGPT展示出人工智能应用的巨大价值,OpenAI公司的估值因此一飞冲天,最大的外部投资者微软公司更因此获利巨大。
其他几家科技巨头不可能对此视而不见,尤其是谷歌公司,多年来一直被认为在人工智能研究领域处于世界领先位置,如今被OpenAI抢了先机,谷歌只能寻机后发制人。
果然,谷歌在2023年底推出了“双子座”(Gemini)。
这款多模态大模型人工智能产品在32项功能的评测中有30项的表现超过了ChatGPT。
除了在文字方面的输出看上去与ChatGPT不相上下,它还对图片和视频有着超强的理解和推理能力,同时可以针对提问给出混合文字和图像的多模态输出——这是ChatGPT 尚不具备的。
2024年初,谷歌的聊天机器人Bard已融合了Gemini的能力,升级版Bard的表现完全不逊于ChatGPT。
而与此同时,OpenAI又发布了文生视频大模型Sora,它能根据提示词生成60秒的连贯视频,这预示着一个新的视觉叙事时代的到来。
差不多同时,DeepMind公司和斯坦福大学的研究人员合作开发的Mobile ALOHA机器人问世。
它是一对可以使用锅碗瓢盆、操作家用电器乃至洗衣叠被的机器臂,精细程度不输人类。
2024年中考英语考前最后一卷(常州卷)注意事项:1.全卷满分90分。
考试时间为100分钟。
试题包含选择题和非选择题。
考生答题全部答在答题卡上, 答在本试卷上无效。
2.请认真核对监考教师在答题卡上所粘贴条形码的姓名、考试证号是否与本人相符合,再将自己的姓名、考试证号用0. 5毫米黑色墨水签字笔填写在答题卡及本试卷上。
3.答选择题必须用2B铅笔将答题卡上对应的答案标号涂黑。
如需改动,请用橡皮擦干净后, 再选涂其他答案。
答非选择题必须用05毫米黑色墨水签字笔写在答题卡的指定位置,在其他位置答题一律无效。
第I卷(选择题共56分)一、单项选择(本题共10小题;每题1分,满分10分)从A、B、C、D 四个选项中,选出可以填入空白处的最佳选项,并在答题卡上将该项涂黑。
1.China’s women’s table tennis team won the champion at the ITTF World Team Table Tennis Finals ________ February 24, 2024.A.at B.on C.in D.to2.Many companies have realized that the live stream (直播) is a great way to attract ________.A.explorers B.customers C.managers D.inventors3.My new teacher was _____ different from what I’d imagined. He was so friendly that I wasn’t nervous at once.A.properly B.smoothly C.completely D.hardly4.—Online payment has made a great difference to people’s life.—Exactly. We ________ keep a wallet in our pocket now.A.needn’t B.shouldn’t C.mustn’t D.can’t5.Don’t worry about the uncertain future. ________, it’s more important to take the present chance to get success.A.What’s more B.As a result C.After all D.In all6.Working as a teacher should be kind-hearted ________ patient.A.as far as B.as good as C.as possible as D.as well as7.________ the great ancient books ________ the writers’ experience are shared with the TV viewers on an educational TV show—China in the Classics (《典籍里的中国》).A.Neither; nor B.Either; or C.Both; and D.Not only; but also8.—Oh, baby! I didn’t expect you ________ such a beautiful card for me. Thank you!—I’m glad you like it, mum. Happy birthday!A.had made B.have made C.would make D.will make9.Sora surprises the world with very wonderful videos. I wonder ________.A.how soon will Sora be widely put into useB.how does Sora turns words into a 60-second videoC.how long it takes Sora to turn words into a videoD.that Sora has more advantages than ChatGPT10.—Many people don’t think women are good at d riving cars.—________. Amy drives better than me because she is more careful.A.That’s not the case B.That’s all rightC.I’m sorry to hear that D.I couldn’t agree more二、完形填空(共12小题;每小题1分,满分12分)阅读下面短文,从短文后各题所给的A、B、C、D四个选项中,选出最佳选项。
a r X i v :0709.0173v 2 [h e p -e x ] 19 S e p 2007αS from LEPS Kluth Max-Planck-Institut f¨u r Physik,F¨o hringer Ring 6,D-80805M¨u nchen,Germany E-mail:skluth@mppmu.mpg.de Abstract.Recent results on measurements of the strong coupling αS from LEP are reported.These include analyses of the 4-jet rate using the Durham or Cambridge algorithm,of hadronic Z 0decays with hard final state photon radiation,of scaling violations of the fragmentation function,of the longitudinal cross section,of the Z 0lineshape and of hadronic τlepton decays.1.Introduction Determinations of the strong coupling constant αS using data from the LEP experiments ALEPH,DELPHI,L3and OPAL are among the most precise and least ambiguous measurements [1].The initial state is purely leptonic avoiding initial and final state interference,the data samples are generally large and the experiments have large acceptances,good resolutions and low backgrounds resulting in small experimental corrections.When the re-analysed data from the PETRA experiment JADE are included a centre-of-mass (cms)energy range of more than an order of magnitude is covered by many sets of measurements.The LEP program ran from 1989to 2000and covered cms energies from 89to 209GeV.The samples of hadronic events in e +e −annihilation contain O (105−6)events near m Z 0(LEP 1),O (102−3)events at higher energies (LEP 2)and O (103−4)events below m Z 0from JADE between 14and 44GeV cms energy.2.4-jet rate In the analyses [2,3,4,5]hadronic final states are clustered using the Durham algorithm,which defines y ij =2min 2(E i ,E j )(1−cos θij )/E 2vis .as the phase space distance between two particles i,j with energies E i and E j with E vis .= k E k .The pair with the smallest y ij is combinedby adding the four-vectors.The procedure is repeated until all y ij >y cut .The fraction of four-jet events R 4(y cut )is studied as a function of y cut .DELPHI uses the Cambridge variant of the Durham algorithm.Since a four-jet final state corresponds to at least four partons in QCD the prediction is O (α2S )in leading order (LO).The relative error ∆αS /αS =∆R 4/(2R 4),i.e.a precise measurement of αS is possible if experimental uncertainties can be kept under control.The data,corrected for experimental effects,are compared with NLO calculations combined with resummed next-to-leading logarithm (NLLA)terms (DELPHI use NLO only)including hadronisation corrections derived from simulation.The results are summarised in figure 1.The average value αS (m Z 0)=0.1172±0.0010(exp .)±0.0016(had .)±0.0014(theo .)was found assuming partially correlated experimental uncertainties while hadronisation and theory uncertainties were evaluated by repeating the procedure with simultaneously changed input values.Since the dependency of αS on the renormalisation scale (RS)in the theory is at aminimum in the analyses the conventional estimation ofof the RS may yield an underestimate[4,5].JADEOPALDELPHIALEPHe+e- RαS(mZ)Figure1.Results forαS(m Z0)from the four-jet rate R4[2,3,4,5].The dashed vertical lineand shaded band indicate the average value witherrors shown on thefigure.1010√s [GeV]αSFigure 2.Summary of results forαS.The solid and dashed lines and the grayband show the the running ofαS usingthe average value ofαS(m Z0)given on thefigure.The label“NNLO incl.”refersto measurements discussed in section 5.Adapted from[1].3.Radiative Z0decaysHadronic decays of the Z0with energetic and isolated photons can be used to study QCD at lower effective cms energies√s′≤78GeV.The event shape analysis uses NLO+NLLA QCD calculations including hadronisation corrections predicted by simulations;thefitted theory is found to be consistent with the data.Within the uncertainties of the analysis assuming factorisation of hard and isolated photon radiation and QCD radiation leads to a good description of the data.4.FragmentationIn studies of fragmentation in e+e−annihilation to hadrons production of charged particles is measured.The distributions of x=2p/√s in the static quark-parton model.Dependence on√gauge boson appears with longitudinal polarisation,the so-called longitudinal cross sectionσL. Since longitudinal polarisation is only possible with an additional gluon in thefinal stateσL can be used to measureαS.In[1]measurements ofσL by ALEPH,DELPHI and OPAL are averaged with the resultσL/σtot.=0.056±0.002.This yieldsαS(m Z0)=0.117±0.008using a NLO QCD calculation.The average forαS(m Z0)from fragmentation analyses in e+e−annihilation from[1] isαS(m Z0)=0.118±0.004(exp.)±0.001(had.)±0.007(theo.).5.Z0lineshape and hadronicτdecaysIn[1]the results of the Z0lineshape measurements[8]were used to extract measurements of αS(m Z0)from four sensitive observables:the hadronic widthΓh,the ratio of hadronic and leptonic widths R Z,and the total peak cross sections for hadron and lepton productionσh and σℓ.The dependence on the RS[9]and the Higgs mass are studied.The result based on NNLO QCD calculations isαS(m Z0)=0.1189±0.0027(exp.)±0.0015(theo.).The analysis of the hadronic branching ratio Rτof theτlepton in[10,1]uses NNLO QCD calculations.Contributions from non-perturbative processes are estimated using the spectral functions d Rτ/d s forfinal states with even or odd numbers of pions and turn out to be consistent with zero for Rτ.The result isαS(m Z0)=0.1221±0.0006(exp.)±0.0004(had.)±0.0019(theo.).A similar analysis[11]uses partially calculated NNNLO terms in addition and is consistent.In both cases the theoretical uncertainty is determined by varying the renormalisation scale between0.5and2.0of the central value such that the theory errors can be compared directly with other results.6.SummaryThe most reliable measurements ofαS are those based on NNLO calculations and with small hadronisation uncertainties and thus small model dependence.The average of the results from section5with a related measurement using the total cross section for hadron production in e+e−√annihilation at low。
2024年广东省深圳高级中学高三(上)第三次诊断物理试卷一、选择题:本大题共11小题,第1-8小题每小题3分,第9-11小题每小题6分,共42分。
1.日本于2023年8月24日将福岛第一核电站核废水排入大海,对海洋生态造成恶劣影响。
核废水中含有氚、锶90、铯137、碘129等放射性元素,其中铯137的半衰期约30年,衰变方程为 13755Cs→13756Ba+X。
下列说法正确的是( )A. X是α粒子B. X是β粒子C. 衰变过程中质量守恒D. 100个铯137原子核经过30年后一定还有50个未衰变2.如图所示,这是一种古老的舂米机。
舂米时,稻谷放在石臼A中,横梁可以绕O点转动,在横梁前端B点固定一舂米锤,脚踏在横梁另一端C点往下压时,舂米锤便向上抬起,提起脚,舂米锤就向下运动,击打A 中的稻谷,使稻谷的壳脱落,稻谷变为大米。
已知OC>OB,则在横梁绕O点转动的过程中( )A. 在横梁绕O点转动过程中,B、C两点的加速度大小相等B. 舂米锤击打稻谷时对稻谷的作用力大于稻谷对舂米锤的作用力C. 在横梁绕O点转动过程中,B点的速度大于C点的速度D. 脚踏在横梁另一端C点往下压的过程中,舂米锤的重力势能增大3.如图所示,在竖直墙壁上固定水平轻杆OB,B为铰链装置,OA为轻质细绳且与水平方向夹角θ=30°,小球质量为m,通过轻绳系于O点,初始时整个装置处于静止状态,现保证O点位置不变,逐渐减小绳OA 的长度,使绳的上端由A点缓慢移动至C点。
已知重力加速度为g,不计所有摩擦,则下列说法正确的是( )A. 初始时OA绳的拉力大小为3mgB. 移动过程中OA绳的拉力大小逐渐增大C. 移动过程中OB杆的弹力逐渐减小D. 最终OA绳的拉力大小减小至04.神舟十六号是中国“神舟”系列飞船的第十六次任务,也是中国空间站运营阶段的首次飞行任务。
如图所示,神舟十六号载人飞船处于半径为r1的圆轨道Ⅰ、空间站组合体处于半径为r3的圆轨道Ⅲ,两者都在其轨道上做匀速圆周运动。
广东省惠州市2024届高三第三次调研考试试题语文试题一、现代文阅读(35分)(一)现代文阅读I(本题共5小题,19分)阅读下面的文字,完成1~5题。
材料一:自古以来,人们以为海洋有着无穷大的容量,因此认为它是陆地废弃物的天然归宿。
从上世纪五十年代开始,随着化工业、核工业的发展和人口的增长,海洋成了各国有毒废料尤其是具有放射性的核废料的倾倒空间。
核工业产生的废料,还有核武器和核事故产生的放射性物质,在过去的几十年间大量进入海洋。
从1946年大约80千克低放射性的核废料在加利福尼亚投入太平洋开始,到1982年约550千克核废料投入大西洋的西欧陆架为止,这36年里投入海洋的核废料,总的放射性活度高达63Bq,相当于每秒钟发生6.3亿亿次核衰变的放射性。
目前,大多数核废料都是装在金属桶里沉到海底,可是在上世纪的五十年代和六十年代,有些核废料不加包装就直接投入海洋。
幸好这种危害全人类的做法,早已被制止。
为了控制废物的海洋投放,1972年全球各国在伦敦召开政府间会议并通过了《伦敦倾废公约》,约定全面禁止放射性废物投放海洋。
在公约通过之后,大多数负责任的国家坚决遵守公约。
此后虽然“禁而不止”的事件偶有发生,会有极个别国家将核潜艇的核反应堆废物秘密投进海洋,但总的来说,明目张胆往海洋丢弃核废料的时代已经结束。
对于核废料,有的从开始就没有认真处理,有的装入核废料桶后投入海底,但由于遭受生物化学的腐蚀,很多也已经发生渗漏。
往往前代人种下的苦果,要留给后代人去品尝。
著名的比基尼环礁就是一例。
1946年7月1日,美国在太平洋中部马绍尔群岛的比基尼环礁进行了战后首次核爆炸试验。
到上世纪九十年代,美国总共在马绍尔群岛进行了67次试验,最大的一次爆炸量达1500万吨,相当于1000多颗广岛原子弹。
1954年的一次试验炸掉了比基尼两座珊瑚礁,炸出一个100米深的大坑,这一带的岛礁受到严重的放射性污染。
统计结果显示,比基尼环礁及其周边海域至少有42种当地原有生物物种消失,其中有28种生物出现了灭绝现象。
语文本试卷满分150分。
考试用时150分钟。
一、现代文阅读(36分)(一)现代文阅读I(本题共5小题,19分)阅读下面的文字,完成1~5题。
2009年12月7日,举世瞩目的联合国气候变化峰会在丹麦首都哥本哈根召开,经过近2周的激烈争吵,各方最终未能对下一步温室气体减排达成共识。
以下是记者对本次会议中方科技顾问丁仲礼院士的采访。
记者:这次哥本哈根的峰会给人的感觉一直是激烈的争吵,到底在吵什么?丁:就是今后不同的国家还能排放多少二氧化碳。
记者:这个排放多少,对于我们意味着什么?丁:简单讲,就是一个国家以后还能使用多少能源。
对普通国民来说,它意味着生活能否继续改善,福利能否进一步增加,甚至有没有工作。
记者:基于IPCC(联合国政府间气候变化专门委员会)报告对于气候升温的预测,哥本哈根会议提出,相对于1750年工业化前的水平,全球平均气温升高2摄氏度是人类社会可以容忍的最高升温。
对此,您怎么看?丁:许多人都把它理解为一个科学结论,其实这个2摄氏度只是英国某研究机构通过计算机模拟出来的。
随着这个结论的迅速流行,它慢慢变成了一个价值判断。
记者:如果计算机模拟的结果是可信的话,那不算一个依据吗?丁:你怎么知道它可信?它并非科学实验的结果,它只是计算机的模拟。
记者:丁院士,我们当然知道科学界有反对和怀疑的声音,但是IPCC作为各国科学家共同参与的一个组织,它拿出的报告,不应该得到主流科学界的认同吗?丁:科学家有主流吗?科学是根据人多人少来定的吗?科学是真理的判断。
在IPCC报告原文中.并没有确认气候变暖就是由人类活动产生二氧化碳带来的结果,也没有精确的数据表明二氧化碳到底对气候变暖有多大的影响,按照哥本哈根大会达成的控制升温2摄氏度的共识,到2050年全球二氧化碳的最大排放量约为8000亿吨。
这个总量非常非常小。
打个比方,假如我们现在是人均排放1.4吨碳,那么到2050年人均排放量就只有0.8吨碳。
这还是建立在人口总量维持不变的前提之下。
从希格斯粒子到中间玻色子、轻子和夸克的静止质量
希格斯粒子是一种基本粒子,它是由三个基本粒子组成的,它们是上弦子、下弦子和质子。
它们的静止质量是极小的,只有1.674929×10-27千克。
中间玻色子是一种基本粒子,它是由两个基本粒子组成的,它们是上弦子和下弦子。
它们
的静止质量是比希格斯粒子大得多,大约是9.11×10-31千克。
轻子是一种基本粒子,它是由一个基本粒子组成的,它是电子。
它们的静止质量是比中间玻色子大得多,大约是9.11×10-31千克。
夸克是一种基本粒子,它是由三个基本粒子组成的,它们是上弦子、下弦子和质子。
它们
的静止质量是比轻子大得多,大约是1.67×10-27千克。
从希格斯粒子到中间玻色子、轻子和夸克,它们的静止质量是不断增加的。
希格斯粒子的
静止质量最小,而夸克的静止质量最大。
这些基本粒子的静止质量的差异反映了它们的结
构和性质的差异。
它们的结构和性质决定了它们的静止质量,而它们的静止质量又决定了
它们的物理性质。
安徽省滁州市凤阳临淮、明光三中、关塘中学2025届高考英语一模试卷注意事项:1.答卷前,考生务必将自己的姓名、准考证号填写在答题卡上。
2.回答选择题时,选出每小题答案后,用铅笔把答题卡上对应题目的答案标号涂黑,如需改动,用橡皮擦干净后,再选涂其它答案标号。
回答非选择题时,将答案写在答题卡上,写在本试卷上无效。
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第一部分(共20小题,每小题1.5分,满分30分)1.The drums of war are beating once again. As tensions rise between America and Iran, China appeals to both sides to ________.A.stand by B.come alongC.step back D.stick together2.I’ve known Sarah for nearly ten years. She _________ once my customer.A.is B.has beenC.was D.had been3.Had it not been for his experience in the forest,we ____________ in the battle with the fierce bear.A.hadn't survived B.wouldn't have survivedC.didn't survived D.wouldn't survive4.The importance ______ a national day and how it is celebrated are very different from country to country. A.connected to B.given to C.meaning to D.attached to5.My mobile phone is missing. Who it?A.must have taken B.must takeC.could have taken D.could take6.Last December China _____ 100 Chinese and 10 foreigners for their outstandin g contributions to the country’s reform and opening-up.A.distinguished B.sponsoredC.acknowledged D.evaluated7.The matches of the FIFA Women’s World Cup will be played in 2019 all around France, whose men’s team _____ the 2018 World Cup.A.wins B.wonC.has won D.had won8.She is quite________to office work. You had better offer her some suggestions when necessary.A.familiar B.similarC.fresh D.sensitive9.Anyway, we’re here now, so let’s ___________ some serious work.A.come up with B.get down toC.do away with D.live up to10.Mark has lived in China for many years, yet he still can't ________ himself to the Chinese customs.A.observe B.adaptC.lead D.devote11.That Americans have no history while Chinese have no future sounds ________; it has raised a thought provoking question, though.A.artificial B.arbitrary C.allergic D.reluctant12.________ challenges in Chinas car-sharing economy, shared mobility still has a promising future.A.Despite B.BesidesC.Concerning D.Regarding13.Though small, the country has _____ plants from desert grasses to tropical jungle.A.extreme B.abundantC.artificial D.poisonous14.As to the “996 work schedule”, ______ employees work from 9 am to 9 pm, 6 days a week, People’s Daily commented that valuing hard work does not mean forcing employees to work overtime.A.that B.which C.where D.when15.If Kate had known what was _______ for her, she would not have married Tom.A.in response B.in returnC.in reaction D.in store16.---When shall we start the reconstruction of the historic building?--- Not until our program ______ by the authority.A. will approveB. will be approvedC. has approvedD. has been approved17.Faced with economic slowdown, some companies are planning to use robots to ______ human workers to reduce their labor costs.A.compensate B.substituteC.symbolize D.discriminate18.A teacher’s job is not to tell the students what to believe or value, but to ________ them to develop a worldview for themselves.A.urge B.equipC.persuade D.rank19.The doctor’s treatment has worked marvels: the patient has completely.A.repeated B.returned C.recovered D.reminded20.---I saw no more than one motorcar in the shop. Will you go and buy ?---No, I’d rather find in other shops.A.it; oneB.one; itC.it; the oneD.the one; it第二部分阅读理解(满分40分)阅读下列短文,从每题所给的A、B、C、D四个选项中,选出最佳选项。
arXiv:hep-ph/0309016v2 27 Feb 2004AMES-HET-03-06BNL-HET-03/19
ThreeheavyjeteventsathadroncollidersasasensitiveprobeoftheHiggssector
DavidAtwood∗DepartmentofPhysicsandAstronomy,IowaStateUniversity,Ames,IA50011,USA
ShaoulyBar-Shalom†andGadEilam‡PhysicsDepartment,Technion-InstituteofTechnology,Haifa32000,Israel
AmarjitSoni§TheoryGroup,BrookhavenNationalLaboratory,Upton,NY11973,USA(Dated:February1,2008)
Assumingthatanon-standardneutralHiggswithanenhancedYukawacouplingtoabottomquarkisobservedatfuturehadronexperiments,weproposeamethodforabetterunderstandingoftheHiggssector.Ourprocedureisbasedon“counting”thenumberofeventswithheavyjets(where“heavy”standsforacorbjet)versusbjets,inthefinalstateofprocessesinwhichtheHiggsisproducedinassociationwithasinglehighpTcorbjet.Weshowthatanobservedsignalofthetypeproposed,ateithertheTevatronortheLHC,willruleoutthepopulartwoHiggsdoubletmodeloftypeIIaswellasitssupersymmericversion-theMinimalSupersymmetricStandardModel(MSSM),andmayprovidenewevidenceinfavorofsomemoreexoticmultiHiggsscenarios.Asanexample,weshowthatinaversionofatwoHiggsdoubletmodelwhichnaturallyaccountsforthelargemassofthetopquark,oursignalcanbeeasilydetectedattheLHCwithinthatframework.WealsofindthatsuchasignalmaybeobservableattheupgradedTevatronRunIII,iftheneutralHiggsinthismodelhasamassaround100GeVandtanβ>∼50andiftheefficiencyfordistinguishingacjetfromalightjetreachesthelevelof∼50%.
PACSnumbers:12.15.Ji,12.60.Fr,12.60.-i,14.80.Cp
I.INTRODUCTIONWiththeTevatronRunIIunderwayatFermilab,thefutureTevatronupgradeRunIIIandtheLargeHadronCollider(LHC)atCERN,thediscoveryoftheHiggsbosoniscurrentlybelievedtobe“aroundthecorner”.ThesemachineswillbeabletodetecttheneutralHiggsoveritsentiretheoreticallyallowedmassrange[1].
IftheHiggsYukawacouplingtoabottomquarkisen-hanced,aspredictedforexampleingeneralmultiHiggsmodelsandinthesupersymmetricversionofthetwoHiggsDoubletModel(2HDM)-theMSSM-whentanβislarge,thentheneutralHiggsmaybeproducedatLead-ingOrder(LO)throughb¯bfusionb¯b→h[2].Insuchmodels,asizableproductionrateofaneutralHiggsinassociationwithbquarkjetsisalsoexpectedviathesub-processesgb→bh[3,4]andgg,q¯q→b¯bh[5].[1]Inpar-ticular,aswasshownin[3],ifonedemandsthatonlyonebjetwillbeproduced(inassociationwiththeHiggs)athighpT,thengb→bhbecomestheLOandisthereforethedominantHiggs-bottomassociatedproductionmech-anismforlargetanβ.Forexample,gb→bhfollowedbyh→b¯bmayalreadyprovetobeausefulprobeofthe
[2]Wewillnotexplicitlywritethechargeofthequarksinvolved.Allcharge-conjugatesub-processesareunderstoodthroughoutthispaper.2ticularlyiftheHiggs-bottomYukawaislarge,thenthisclassofprocessesmayplayanimportantroleinHiggssearches,discoveryandcharacterizationathadroncol-liders.Basedonthistypeofproductionmechanism,wesug-gestanobservablewhichisparticularlysensitivetonewphysicsintheratiobetweentheHiggs-charmandtheHiggs-bottomYukawacouplings.WefindthatoursignalisinsensitivetotheHiggssectorsofthetypeII2HDM(2HDMII)andoftheMSSM.Therefore,apositivesig-nalofourobservableateithertheTevatronortheLHCwillruleoutthesemodels.Wealsoconsideradifferenttypeofa2HDM,thesocalled“2HDMforthetopquark”(T2HDM),whichisaninterestingmodeldesignedtonat-urallyaccommodatethelargemassofthetopquark.ThismodelmaybeviewedasaneffectivelowenergytheorywhereintheYukawainteractionsmimicsomehighenergydynamicswhichgeneratesboththetopmassandtheweakscale.Thetwoscalardoubletscouldbecom-posite,asintop-colormodels,andtheYukawainterac-tionscouldbetheresidualeffectofsomehigherenergyfour-Fermioperators.Interestingly,forthisT2HDMoursignalissignificantlyenhanced.Wethusshowthatifthisversionofa2HDMunderliestheHiggssector,thenoursignalwillbeeasilydetected(tomanystandardde-viations)attheLHCandmayalsobedetectedattheTevatroniftanβislargeenoughandiftheefficiencyoftaggingacjetasaheavyjetisofO(50%).Thepaperisorganizedasfollows:insectionIIwedefineoursignal.InsectionIIIwepresentthenumeri-calsetupanddiscusstheexperimentalbackground.InsectionIVweevaluateoursignalinthreedifferentver-sionsofa2HDManddiscusstheexpectationsfromtheT2HDM,the2HDMIIandtheMSSM.InsectionVwesummarizeourresults.
II.NOTATIONANDDEFINITIONOFTHESIGNAL
Letjhdenotea“heavy”borc-quarkjet.Specifically,ajhjetshouldnotbeau,d,sorgluonjet(i.e.,withthevetojh=u,d,s,gjet).Letjbbeab-quarkjet.Clearly,everyjetoftypejbisalsoajh.Likewise,letusdenotebyjcac-quarkjet.Wethusdefinethecross-sections
σjhjhjh≡σ(pporp¯p→jhjhjh+X),(1)σjbjbjb≡σ(pporp¯p→jbjbjb+X),(2)
andtheratio
R≡σjhjhjh
Y2b
+O
Y4c
¯σMjbjbjb
,(6)
whereR=¯σjhjhjh/¯σjbjbjbwith¯σjhjhjh,¯σjbjbjbbeingtheeffectivesignalsforcross-sectionsthatwillactuallybemeasuredintheexperimentandRMisthevalueofRcalculatedwithinaspecificHiggsmodelMviathesub-processesgq→qh→qqq,q=corb.Thus,inthelimitofanidealdetectorwhereǫkj=δkj,RM=RM(whereRMmeansthe“ideal”ratiodefinedin(3)calculatedwithinmodelM).Inparticular,thesecross-sectionsincludealltaggingefficienciesasfollows: