August 8 , 2022 (Monday) |
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Time |
Title |
Speaker |
Opening Plenary-I |
Chair:赵政国 |
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8:30-8:45 |
辽宁师范大学校长苑晓杰教授致辞 |
|
8:45-9:20 |
高能物理分会工作报告 |
王贻芳 |
9:20-10:00 |
高能物理现状与展望——Snowmass研究总结 |
韩涛 |
Plenary-II |
Chair:高原宁 |
|
10:30-11:05 |
LHAASO研究进展报告 |
曹臻 |
11:05-11:40 |
TeV 物理实验进展综述 |
李强 |
11:40-12:15 |
微扰QCD和精确计算研究进展 |
朱华星 |
Afternoon Plenary-I |
Chair:邹冰松 |
|
14:00-14:35 |
振幅计算和有效场论研究进展 |
杨刚 |
14:35-15:10 |
格点 QCD 研究进展 |
丁亨通 |
15:10-15:45 |
高能重离子碰撞物理综述 |
黄旭光 |
Afternoon Plenary-II |
Chair:沈肖雁 |
|
16:05-16:40 |
加速器最新原理和技术研究进展 |
李煜辉 |
16:40-17:15 |
强子物理理论研究进展 |
吴佳俊 |
17:15-17:50 |
强子物理实验研究进展 |
周小蓉 |
August 9 , 2022 (Tuesday) |
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Plenary-I |
Chair:岳崇兴 |
|
8:30-9:05 |
未来对撞机研究进展(包括 CEPC 和 STCF) |
李刚 |
9:05-9:40 |
暗物质理论综述 |
刘佳 |
9:40-10:15 |
暗物质测量 |
马豪 |
Plenary-II |
Chair:何小刚 |
|
10:30-11:05 |
中微子理论进展 |
葛韶锋 |
11:05-11:40 |
中微子实验研究进展 |
占亮 |
Afternoon Plenary-I |
Chair:王青 |
|
14:00-16:00 |
高能物理分会换届会议 |
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Afternoon Plenary-II |
Chair: TBA |
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16:30-18:00 |
高能物理分会第十一届委员会第一次会议 |
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14:00-18:30 |
分会报告 |
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August 10 , 2022 (Wednesday) |
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8:30-18:30 |
分会报告 |
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14:00-17:35 |
第十二届“晨光杯”青年优秀论文终评 |
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August 11 , 2022 (Thursday) |
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8:30-16:00 |
分会报告 |
|
Afternoon Plenary (大会闭幕式) |
Chair:赵强 | |
16:10-16:20 |
宣布高能物理分会换届结果 |
王青 |
16:20-16:30 |
第十一届高能物理分会主任致辞 |
|
16:30-17:00 |
“晨光杯”颁奖 |
曹庆宏 |
17:00-17:10 |
致谢,闭幕式 |
|
8月8日 |
8月9日 |
8月10日 |
8月11日 |
大会报告 |
会议号: 878 7825 9514 会议密码:438086 |
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(下午)会议号: 87878259514 会议密码:438086 |
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分会1:TeV物理和超出标准模型新物理 |
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(下午)会议号: 84776531113 会议密码: 662923 |
会议号: 85340063042 会议密码: 219593 |
会议号: 84356016853 会议密码: 577587 |
分会2:强子物理与味物理 |
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(下午)会议号: 89608403352 会议密码: 625234 |
会议号: 85904391430 会议密码: 375223 |
会议号: 86095488848 会议密码: 988365 |
分会3:重离子物理 |
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(下午)会议号: 88487196212 会议密码: 986245 |
会议号: 85480547626 会议密码: 652789 |
会议号: 88623093704 会议密码: 371231 |
分会4:中微子物理、粒子天体物理与宇宙学 |
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(下午)会议号: 85268353255 会议密码: 531259 |
会议号: 87672892060 会议密码: 834462 |
会议号: 85745040226 会议密码: 487957 |
分会5:粒子物理实验技术 |
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(下午)会议号: 87096632702 会议密码: 183776 |
会议号: 88974009618 会议密码: 676932 |
会议号: 89898110557 会议密码: 492184 |
第十二届“晨光杯”青年优秀论文终评 |
|
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(下午)会议号: 83277253505 会议密码: 371743 |
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中国物理学会高能物理分会第十一届全国会员代表大会暨学术年会(大会)
会议号:878 7825 9514
时间:2022年8月8日、9日、11日 08:00 上午
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/87878259514?pwd=dGpEV25jWk9JZ0xZeXFybTFWMGxCUT09
会议密码:438086
分会1:TeV物理和超出标准模型新物理(8月9日下午)
会议号: 84776531113
开始时间: 2022-08-09T13:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/84776531113?pwd=SnoxczlKYm14dll2R0grcHRzejBwZz09
会议密码: 662923
分会2:强子物理与味物理(8月9日下午)
会议号: 89608403352
开始时间: 2022-08-09T13:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/89608403352?pwd=bktTWWhkU2dTeEMvblFiM05uVGtoQT09
会议密码: 625234
分会3:重离子物理(8月9日下午)
会议号: 88487196212
开始时间: 2022-08-09T13:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/88487196212?pwd=bDJxSmlwYy8yd1VqKzdUMTM1ZEtZdz09
会议密码: 986245
分会4:中微子物理、粒子天体物理与宇宙学(8月9日下午)
会议号: 85268353255
开始时间: 2022-08-09T13:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/85268353255?pwd=R2hjYkJFVVVTZllUbER1cFRhTzJnQT09
会议密码: 531259
分会5:粒子物理实验技术(8月9日下午)
会议号: 87096632702
开始时间: 2022-08-09T13:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/87096632702?pwd=cFNyTnQ2WTUrZ1F2ZjdoTVZpUFRaUT09
会议密码: 183776
分会1:TeV物理和超出标准模型新物理(8月10日全天)
会议号: 85340063042
开始时间: 2022-08-10T08:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/85340063042?pwd=TjJJaEdrbzJlOWswQmdqenVnQndEUT09
会议密码: 219593
分会2:强子物理与味物理(8月10日全天)
会议号: 85904391430
开始时间: 2022-08-10T08:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/85904391430?pwd=R3RLY1p0Q0Z0ZHRnL090K1NNYmdEZz09
会议密码: 375223
分会3:重离子物理(8月10日全天)
会议号: 85480547626
开始时间: 2022-08-10T08:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/85480547626?pwd=MFNlWHgzcVIrbTBVN3ozcmtvMnJnQT09
会议密码: 652789
分会4:中微子物理、粒子天体物理与宇宙学(8月10日全天)
会议号: 87672892060
开始时间: 2022-08-10T08:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/87672892060?pwd=aE1tT3RXQUZIUnoxdFJXcFMvZm5aQT09
会议密码: 834462
分会5:粒子物理实验技术(8月10日全天)
会议号: 88974009618
开始时间: 2022-08-10T08:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/88974009618?pwd=dnoySVFHYTh4NlJRTk8rMmYrWHNvZz09
会议密码: 676932
分会1:TeV物理和超出标准模型新物理(8月11日全天)
会议号: 84356016853
开始时间: 2022-08-11T08:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/84356016853?pwd=aW9rRzNLSkJOc0lMSENNUTVYOXpXUT09
会议密码: 577587
分会2:强子物理与味物理(8月11日全天)
会议号: 86095488848
开始时间: 2022-08-11T08:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/86095488848?pwd=M2FWb3ZidUhaZmxyRnZpSXVoc2ZGUT09
会议密码: 988365
分会3:重离子物理(8月11日全天)
会议号: 88623093704
开始时间: 2022-08-11T08:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/88623093704?pwd=MCtUY0Q1RFlHNTNBa3d0ck9DWXZvUT09
会议密码: 371231
分会4:中微子物理、粒子天体物理与宇宙学(8月11日全天)
会议号: 85745040226
开始时间: 2022-08-11T08:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/85745040226?pwd=cWFuK1krUjBmQ2g1dXVadHJoWnc3Zz09
会议密码: 487957
分会5:粒子物理实验技术(8月11日全天)
会议号: 89898110557
开始时间: 2022-08-11T08:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/89898110557?pwd=ODhmUWpVclRvWHZ6S0hpallpOCtkQT09
会议密码: 492184
第十二届“晨光杯”青年优秀论文终评(8月10日下午)
会议号: 83277253505
开始时间: 2022-08-10T14:00:00
Zoom 会议链接:
https://ihep-ac-cn.zoom.us/j/83277253505?pwd=YzNKeWlzNGVUWWhGRnVlNFpLbmlWQT09
会议密码: 371743
各位老师,您好!
由于大连市防疫政策收紧,不允许外地人员参会,为严格遵守疫情防控要求,确保参会人员的健康与安全,高能物理分会决定:原定在大连举行的“中国物理学会高能物理分会第十一届全国会员代表大会暨学术年会”全部转为线上进行,分会第十届委员会换届会议、高能物理分会第十一届委员会第一次会议、第十二届“晨光杯”优秀论文评选活动将同期线上举行。
会议详细日程已在网站发布(网站链接:https://indico.ihep.ac.cn/event/16065/timetable/#20220809),会议远程连接方式也将尽快公布。
各位老师已预定的酒店,会务组将统一取消,您无需在indico修改注册信息。
各地疫情瞬息万变,防控程度不断升级,对此给各位造成的不便和损失,组委会深表歉意,敬请大家谅解!再次感谢各位专家、老师的参与和支持!
中国物理学会高能物理分会秘书处
辽宁师范大学
2022年7月26日
根据大连市的疫情防控要求,经高能物理分会常务委员会讨论决定,原定于2022年8月8日至11日在大连召开由辽宁师范大学承办的中国物理学会高能物理分会第十一届全国会员代表大会暨学术年会现改为线上线下同步进行:大会报告(8日全天、9日上午)线上线下同步进行,分会报告(9日下午、10日和11日全天)完全线上进行。
根据大连市有关疫情防控规定,对本次会议线下参会人数限制为不超过200人。因此,本次会议参会人员调整如下:
1. 线下参会人员:高能物理分会第十届和第十一届委员会全体常委和委员、本次学术年会大会报告特邀报告人、各分会召集人;
2. 线上参会人员:其他参会人员。会议将继续开放线上参会注册。
线上参会人员不缴纳注册费,线下参会人员注册费1500元/人。经高能物理分会常务委员会讨论,建议线下参会人员不携带家属。
对于会议调整给您带来的不便和损失,我们深表歉意,敬请谅解!
之前注册的老师和同学无需修改自己的注册信息,会务组已统一为大家取消之前的住房预定(在非会务组提供酒店预订住房的请自行取消)。
线下参会的老师,请根据新的会议日程修改自己的注册信息,务必将“线下参会”选项改为“是”。
中国物理学会高能物理分会秘书处
辽宁师范大学
2022年7月19日
中国物理学会高能物理分会第十一届全国会员代表大会暨学术年会定于2022年8月8日至11日在大连召开,8月7日注册报到,8月12日离会。会议由中国物理学会高能物理分会主办、辽宁师范大学承办。大会组委会诚挚邀请各位同仁参加本届会议。第十二届“晨光杯”优秀论文评选活动同期举行,诚挚邀请各位委员在征集范围内积极组织、推荐论文参选。
会议主要内容:
一、交流国内外高能物理和粒子物理领域最新研究成果和进展。
本次大会将按照下面五个研究领域来组织报告,并在每个领域中包含实验和理论研究进展:
1. TeV物理和超出标准模型新物理(召集人: 张昊 zhanghao@ihep.ac.cn,肖朦,黄燕萍,于江浩)
2. 强子物理与味物理(召集人: 杨振伟 yangzw@pku.edu.cn,郭奉坤,马滟青,刘北江)
3. 重离子物理(召集人: 秦广友 guangyou.qin@mail.ccnu.edu.cn,徐庆华,唐泽波,宋慧超)
4. 中微子物理、粒子天体物理与宇宙学(召集人: 查敏 zham@ihep.ac.cn,郭宗宽,于泽源,孟月)
5. 粒子物理实验技术(召集人: 钱森 qians@ihep.ac.cn,赵雷,张亮,韩柯)
欢迎大家积极提交报告,报告提交截止时间为7月10日。进一步详细的报告安排及日程将在下一轮通知和会议网站中发布。
二、第十二届“晨光杯”青年优秀论文评选活动及颁奖。
高能物理分会每两年举办一次青年优秀论文评选活动。第十二届“晨光杯”青年优秀论文评选活动与第十一届全国会员代表大会暨学术年会同期举办,欢迎青年科技人员积极参加评选活动,并邀请各位高能物理分会的常委和委员积极组织、推荐优秀论文参选。参加评选活动的条件:
1. 申请人是从事高能物理(包括粒子物理理论和实验、中高能核物理、宇宙线和高能天体物理等)科研工作的35岁以下尚未获得高级科教职称的青年科研人员(即不接受已经获得教授、副教授以及同等职称的研究人员参评)。
2. 申报论文必须是申请截止日期以前,已正式发表的论文或已接受发表的论文。
3. 申请人应为申报论文的主要贡献者,且申请人及申报论文的第一单位为国内单位。
4. 参评论文正式发表时间为上次“晨光杯”评选活动截止(2020年3月31日)后正式发表的论文。
申请于2022年4月30日截止(以电子邮件接收时间为准)。符合条件的申请人将申报论文、《申请—推荐表》及所需之两位《专家评阅意见表》(已正式发表的论文不必填写此表)的电子版文件(表格下载地址: https://indico.ihep.ac.cn/event/16065/overview),在截止日期前发送至学会秘书处(邱雯:qiuw@ihep.ac.cn)。学会秘书处将对申请人和所申报的论文进行资格审查,并根据申报论文的专业内容,组织专家初评。初评入围论文作者将在本届全国高能物理大会上报告论文成果,经终评评委无记名投票遴选出“晨光杯”青年优秀论文获奖者。
“晨光杯”将设一等奖1-3名,二等奖3-6名。高能物理分会将对获奖者颁发获奖证书和奖金。
三、大会安排张贴报告展示环节,对海报格式没有要求。
会议有关事项:
1. 会议时间:2022年8月8日-8月11日,8月7日报到。
2. 会议地点:大连国际会议中心。
3. 住宿酒店:大连富丽华大酒店及周边经济型酒店。
(富丽华大酒店和国际会议中心前安排早晚往返大巴)
4. 会议注册:注册费为教师1800元/人,学生和博士后1200元/人。会议协助安排食宿,费用自理。可为参会家属提供会议用餐,收费标准为800元/人。大会对部分退休人员有一定的资助名额(免注册费),名额有限,以申请审核为准。
(鉴于八月份为大连旅游旺季,请大家务必于5月31日前完成网上注册。)
5. 地方会务组联系人:
郭禹辰(会务协调人)电话: 155 0411 8985, Email: ycguo@lnnu.edu.cn
李春花(会务协调人)电话: 159 0985 6053, Email: chunhua@lnnu.edu.cn
杨冀翀(会务协调人)电话: 139 2007 5831, Email: yangjichong@lnnu.edu.cn
杨 硕(会务协调人)电话: 158 4060 6978, Email: shuoyang@lnnu.edu.cn
赵振华(会务协调人)电话: 151 6402 3728, Email: zhaozhenhua@lnnu.edu.cn
周兴玉(会务协调人)电话: 188 1045 7601, Email: zhouxy@lnnu.edu.cn
6. 分会秘书处联系人:
邱 雯(分会秘书) 电话:010-88235843(办公室), Email:qiuw@ihep.ac.cn
赵 强(分会秘书长)电话:010-88236578(办公室), Email:zhaoq@ihep.ac.cn
7. 致谢:本次会议受到国家自然科学基金委和中国高等科学技术中心的资助。
中国物理学会高能物理分会秘书处
辽宁师范大学
二○二二年三月十日
Chair:赵政国
Chair:高原宁
Chair:邹冰松
Chair:沈肖雁
Chair:岳崇兴
Chair:何小刚
散射截面是研究粒子基本结构和相互作用的基本观测量。当散射过程涉及多个能标时,精确计算结果很难得到。当能标之比很大时,结果会展示出大对数结构。在领头幂次阶,该大对数已经了解的比较清楚了。但是在次领头幂次阶,会出现新的困难,例如端点发散。这时需要发展新的理论来处理这些困难。我将介绍这方面的最新进展。
We investigate the extent to which perturbative calculations of the electroweak phase transition are arbitrary and uncertain, owing to their gauge, renormalization scale and scheme dependence, as well as treatments of the Goldstone catastrophe and daisy diagrams. Using the complete parameter space of the Standard Model extended by a real scalar singlet with a Z2 symmetry as a test, we explore the properties of the electroweak phase transition in general Rxi and covariant gauges, OS and MSbar renormalization schemes, and common treatments of the Goldstone catastrophe and daisy diagrams. Reassuringly, we find that different renormalization schemes and different treatments of the Goldstone catastrophe and daisy diagrams typically lead to only small changes in predictions for the critical temperature and strength of the phase transition. On the other hand, the gauge and renormalization scale dependence may be significant, and often impact the existence of the phase transition altogether.
我们将报告LHCb实验在奇特强子态产生测量方面的结果。
Double J/psi at CMS
A near-threshold peaking structure, dubbed X(3960), is observed in the Ds+Ds- mass spectrum with significance greater than 12 standard deviations, using proton-proton collision data collected with the LHCb detector at centre-of-mass energies of 7, 8 and 13 TeV. Its quantum numbers is measured to be J^{PC}=0^{++} with the amplitude analysis. It may be a candidate with the quark content: c cbar s sbar candidate.
The first discovery of pentaquarks at LHCb in 2015, opens new window to study QCD. The LHCb experiment has the large dataset and excellent detector performance in such searches. In this talk, the latest results on pentaquark study in B-meson decays from LHCb will be discussed.
We calculate the s-wave scattering length in the $0^+$ sector of $\eta_c\eta_c$ and the $2^+$ sector of $J/\psi J/\psi$ using three $N_f=2$ twisted mass gauge ensembles
with the lattice spacing $a=0.0667,0.085,0.098$ fm, respectively.
The scattering lengths are extracted using the conventional L{\"u}scher finite size method. We observe significant discretization effects and therefore perform a continuum extrapolation. Finally, we obtain the results as $a^{0^+}_{\eta_c\eta_c}=-0.104(09)$ fm and $a^{2^+}_{J/\psi J/\psi}=-0.165(16)$ fm, where the errors are statistical errors with the uncertainties of lattice spacing taken into account. Both scattering lengths are negative, indicating that the interaction between the two charmonia are repulsive in nature in both channels being studied.
Two-particle correlations with $V^{0}$ $(K^{0}_{S}, \Lambda/\bar\Lambda)$ and charged hadrons as trigger particles of transverse momentum
$8 < p_\mathrm{T,trig}< 16$ GeV/c, and associated charged particles of $1 < p_\mathrm{T,assoc}< 8$ GeV/c, are studied at mid-rapidity in pp and most central Pb-Pb collisions at $\sqrt{s_\mathrm{NN}}$ = 5.02 TeV with the ALICE detector at the LHC.
After contributions of the flow background is subtracted, the per-trigger yields are extracted, and the nuclear modification factor, $I_\mathrm{AA}$, is calculated on both near and away side.
The results of $I_\mathrm{AA}$ show strongly suppression on away-side and enhancement at low $p_\mathrm{T}$ on both near- and away-side consistence with previous ALICE measurement of neutral pion ($\pi^{0}$-h) and charged hadrons (h-h) in Pb-Pb collisions at $\sqrt{s_\mathrm{NN}}$ = 2.76 TeV. In addition, the data are described within uncertainties by AMPT and HIJING event generators.
Chair: 查敏
This talk will present the R&D; study of the prospect and feasibility to deploy the fixed-target experiment utilizing the high rate single electron beam from the SHINE facility under construction. The project is officially sponsored by NSFC Original Exploration Project 2021 and Shanghai pilot program for basic research.
Chair:王青
To resolve the long-standing discrepancy between the precision measurement of bottom quark forward-backward asymmetry at LEP/SLC and the Standard Model prediction,
we propose four different novel methods to probe the $Zbb$ couplings by measuring $gg\to Zh$ production, Z boson exclusive decay at the LHC and (average jet charge weighted) single-spin asymmetry at the HERA and EIC. We demonstrate that $gg\to Zh$ cross section, the branching ratio of $Z\to \Upsilon(ns)+\gamma$,
and jet charge weighted single-spin asymmetry are sensitive to the axial-vector component of the $Zbb$ coupling, while the single-spin asymmetry is sensitive to the vector component. The apparent degeneracy of the $Zbb$ couplings implied by the LEP precision electroweak measurements could be resolved by the current 13 TeV LHC $Zh$ data.
We also show the potential to verify or exclude the LEP data and resolve the AFB puzzle through those methods.
As one of those long-standing experimental anomalies from the LEP era, albeit mild, the discrepancy to the standard model prediction in the $Zb\bar b$ coupling keeps drawing attention over the years as the LHC accumulates data. So far, differential data and studies from electroweak production of the bb pair and other potentially sensitive channels at the LHC and LHCb are yet to become competitive with the existing $Z$-pole measure from LEP. We propose in this study to look at another LHC signal, the $b\bar b +Z/\gamma (\to \ell\ell)$ associated production, both on and off-Z-mass-shell region. The varying dependence on the concerned couplings through interplay of Z and photon interference pattern in the $b\bar b\ell\ell$ final states offer distinct constraint power.
The ForwArd Search ExpeRiment (FASER), is a recently proposed experiment at the LHC that can detect light, long-lived particles. In this work we study the prospect of detecting light CP-even and CP-odd scalars at the FASER. We develop the general formalism for the scalar production and decay from mesons at LHC, given modified couplings of the scalars to the SM particles, as well as summarizing the relevant GeV-scale experiment constraints. We then analyze the light scalars in the large $\tan\beta$ region of the Type-I 2HDM, in which a light scalar with relatively long life time could be accommodated.
The three generations of leptons and quarkons have been discovered. The left-right asymmetry in the weak interaction of leptons and quarks has been confirmed. Astronomical observations have showed that the number of baryons and antibaryons is asymmetrical in the observabale cosmos. This paper shows that there is the same origin of the left-right asymmetry and the asymmetry of number of baryons and antibaryons. The three generations of leptons and quarkons and the two sorts of asymmetry are explained in this paper based on the SU(5) grand unified model with hadrons as nontopological solitons.
We investigate the $T_{cc}^{+}$ as a $DD^{*}$ molecule with $J^{P}=1^{+}$ in the framework of the one-boson-exchange potential model. The isospin breaking effect and $S-D$ wave coupling are taken into account carefully. We adopt the complex scaling method to study the $DD^{*}$ system and obtain a quasibound state corresponding to the $T_{cc}^{+}$.
Summary: The binding energy of $DD^*$ system relative to the $D^{0}D^{*+}$ and width are $-354$ keV and $61$ keV respectively. The isospin breaking effect is found to be enormous, and the $S-$wave $D^{0}D^{*+}$ and $D^{+}D^{*0}$ components give dominant contributions with the probabilities of $72.1\%$ and $27.1\%$ respectively. In addition, we do not find any resonances in the $DD^{*}$ system. As a by-product, we study the $X(3872)$ as a $(D\bar{D}^*-D^*\bar{D})/\sqrt{2}$ molecule with $J^{PC}=1^{++}$. We also find a quasibound state corresponding to the $X(3872)$. Its binding energy relative to the $D^{0}\bar{D}^{*0}$ threshold and width are $-111$ keV and $26$ keV respectively. The $S-$wave $(D^{0}\bar{D}^{*0}-D^{*0}\bar{D}^{0})/\sqrt{2}$ component dominates this state with the probability of $92.7\%$.
Chair:李祖豪
AMS自2011年开始在国际空间站上运行,迄今已在暗物质和反物质寻找、宇宙线研究取得重大成果,发现了许多不能被现有理论解释的新现象。美国白宫已于2021年12月31日宣布国际空间站将运行到2030年,并计划运行AMS直到国际空间站使命结束。为进一步提高AMS科学产出,理解已发现的新现象,特别是宇宙线正电子、反质子和高电荷原子核能谱的精确测量,更好地发挥在反物质等探索研究方面独到的优势,AMS实验计划于近期开始进行探测器升级,安装由两层共8平方米的硅微条探测器组成的Layer0硅径迹室。
中科院高能所将负责完成L0 硅径迹室的全部硅探测器的研制,并参加其总体集成和空间环境模拟试验。AMS实验的其它国际合作者将负责读出电子学、机械结构、冷却、供电、空间验证和安装等,NASA已基本同意中国科学家以这种方式参加升级项目。探测器整体精度要求10微米,是一项前所未有的挑战。本文将向大会介绍AMS L0 硅径迹室升级的建造方案,并汇报进展情况。
本次升级对中国科学家而言,既可以掌握先进的硅探测器技术,也可以了解相关空间技术及质量控制,对中国下一代的空间科学项目,如中国空间站上的HERD实验具有十分重要的意义。
This poster will present a measurement of the charge conjugation and parity ($CP$) properties in the Higgs boson interaction with $\tau$ leptons. The Yukawa interaction is generalized with a single mixing angle parameter $\phi_{\tau}$ to describe $CP$-odd interactions between the Higgs boson and $\tau$ leptons. The study is based on a measurement of $CP$-sensitive angular observables defined by the visible decay products of $\tau$ lepton decays, performed using a data sample corresponding to 139 fb$^{-1}$ of proton–proton collisions recorded at a center-of-mass energy of $\sqrt{s}$= 13 TeV with the ATLAS detector at the Large Hadron Collider.
Without assuming Standard Model hypothesis for the $H\rightarrow\tau\tau$ signal strength,
the mixing angle $\phi_{\tau}$ is measured to be $9 \pm 16^{\circ}$, with an expected value of $0 \pm 28^{\circ}$ at the 68\% confidence level.
The pure $CP$-odd hypothesis is disfavoured at 3.4 standard deviations.
The results are compatible with the predictions for the Higgs boson in the Standard Model as well as $CP$-violating scenarios.
In the SM effective field theory (SMEFT), the gauge interactions can be extended by dimension-8 operators contributing to anomalous triple gauge couplings (aTGCs) and anomalous quartic gauge couplings (aQGCs). The VBS processes at hadron colliders and the tri-boson production at lepton-colliders are suitable for probing aQGCs, and the di-boson production at lepton-colliders is suitable for studying nTGCs. We discuss the event selection strategies for measuring aQGCs or nTGCs, and give constraints on the anomalous gauge couplings. The validity of SMEFT has been taken into account in our works.
格点模拟为计算早期宇宙对称性破缺过程及其可能产生的随机引力波功率谱提供了可能,这为引力波探测实验提供了重要的随机引力波源,引力波探测实验可以和对撞机实验互补的来区分早期宇宙对称性破缺的模式及其背后的新物理。我将在此报告中和大家分享我们利用格点规范场论模拟早期宇宙对称性破缺过程所取得的一些进展,包括:强一阶电弱相变和宇宙弦形成等的研究。
BESIII has collected 2.93 and 6.32 fb^-1 of e+e- collision data samples at 3.773 and 4.178-4.226 GeV, respectively. We will report precision measurements of fDs, |Vcs| and test of lepton flavor universality by studying the leptonic decays of Ds -> l+nu with tau+ -> rho+nu, pi+nu, and e+nunu. We will also report the studies of Ds -> pi0pi0e+nu and KSKSe+nu, inclusive Ds semileptonic decay, updates of D-> Ke nu with a new method.
BESIII has collected 2.93 and 6.32 fb^-1 of e+e- collision data samples at 3.773 and 4.178-4.226 GeV, respectively. We will report the observation of a new a0 resonance and amplitude analyses of Ds -> KSK+pi0, KSKSpi+, pi+pi0eta', KK3pi, Kpipipi0, and pi+pi0pi0. We will also report the transverse polarization determination in D0 -> omega phi, the KS/KL asymmetry studies in D0 -> KLX (X=eta, eta', omega and phi), observation of the new decay mode D^*0 to D^0 e^+e^-, and the measurements of the branching fractions of some D0(+) CF and DCS decays will also presented. In addition, BESIII has collected 4.5 fb^-1 of e+e- collision data between 4.6000 and 4.6999 GeV. This unique data offers ideal opportunity to determine absolute branching fractions of Lambda_c+ decays. We will report the first observation of Lambda_c+ -> npi+.
We will report selected recent results of new physics searches at LHCb via the study of b-hadrons decays that are rare or forbidden in the standard model of particle physics.
BESIII has collected 2.5 B $\psi(2S)$ events and 10 B $J/\psi$ events. The huge data sample provide an excellent chance to search for new physics in charmonium decays. We report the search for the decay $J/\psi\to\gamma + invisible$ and a potential light Higgs A0 in radiative J/psi decay. We also search for the J/psi rare weak decay to $D^-e^+\nu_e +c.c.$, and present the most stringent constraints of $10^{-6}$ at 90\% confidence level. The huge J/psi data set also produce lots of hyperon events at BESIII, which allow us to search for the rare decay of hyperon, such as the invisible decay of Lambda, \Xi semi-leptonic decay. The FCNC process for D0->pi0 vv is also search with the near threshold D0 events at BESIII.
We accomplish the analytical computation of the pure weak annihilation non-leptonic $B$-meson decay amplitudes at leading power in the heavy quark expansion. The novel observation regarding such fundamental hadronic quantities is that adding the missing hard-collinear contribution on top of the hard gluon exchange effect eliminates rapidity divergences entering the convolution integrals of factorization formulae.
Subsequently we identify the perturbative enhancement mechanism due to the penguin contractions of the current-current operators from the weak effective Hamiltonian,
which yields the significant impacts on the CP violating observables.
We compute for the first time the long-distance penguin contribution to the double radiative $B$-meson decays
due to the purely hadronic operators acting with the electromagnetic current in the background soft-gluon field
from first field-theoretical principles by introducing a novel subleading $B$-meson distribution amplitude.
The numerically dominant penguin amplitude arises from the soft-gluon radiation off the light up-quark loop rather than the counterpart charm-loop effect on account of the peculiar analytical behaviour of the short-distance hard-collinear function. Importantly the long-distance up-quark penguin contribution brings about the substantial cancellation of the known factorizable power correction possessing the same multiplication CKM parameters, thus enabling $B_{d, \, s} \to \gamma \gamma$ to become new benchmark probes of physics beyond the Standard Model.
在文章arXiv:2112.14215(李新强,沈萌,王东洋,杨亚东,袁兴博)和arXiv:2205.02205(李新强,谢泽俊,杨亚东,袁兴博)中,我们分别研究了用具有顶夸克味改变和味守恒中性流的$Z^\prime$模型来解释$b\to s \ell^+ \ell^-$反常。在后一工作中,我们还考虑了额外解释最近CDF观测到的W玻色子质量的可能性。
Chair:宋黎明
Lithium chloride water solution is a good option for solar neutrino detection. The $\nu_{e}$ charged-current (CC) interaction cross-section on ${}^{7}\mathrm{Li}$ is evaluated with new B(GT) experimental measurements. The total CC interaction cross-section weighted by the solar ${}^{8}\mathrm{B}$ electron neutrino spectrum is $3.759\times10^{−42}~\mathrm{cm}^{2}$, which is about $60$ times that of the neutrino-electron elastic scattering process. The final state effective kinetic energy after the CC interaction on ${}^{7}\mathrm{Li}$ directly reflects the neutrino energy, which stands in sharp contrast to the plateau structure of recoil electrons of the elastic scattering. With the high solubility of LiCl of $74.5 ~\mathrm{g}/100 ~\mathrm{g}$ water at $10{}^{\circ}\mathrm{C}$ and the high natural abundance of $92.41\%$, the molarity of ${}^{7}\mathrm{Li}$ in water can reach $11 \mathrm{mol/L}$ for safe operation at room temperature. The CC event rate of $\nu_{e}$ on ${}^{7}\mathrm{Li}$ in the LiCl water solution is comparable to that of neutrino-electron elastic scattering. In addition, the $\nu_{e}$ CC interaction with the contained ${}^{37}\mathrm{Cl}$ also contributes a few percent of the total CC event rate. The contained ${}^{35}\mathrm{Cl}$ and ${}^{6}\mathrm{Li}$ also make a delay-coincidence detection for electron antineutrinos possible. The recrystallization method is found to be applicable for LiCl sample purification. The measured attenuation length of $11\pm1$ m at $430 \mathrm{nm}$ shows that the LiCl solution is practicable for a $10\mathrm{-m}$ diameter detector for solar neutrino detection. Clear advantages are found in studying the upturn effect of solar neutrino oscillation, light sterile neutrinos, and Earth matter effect. The sensitivities in discovering solar neutrino upturn and light sterile neutrinos are shown. More details of the work can be found in arxiv:$2203.01860$.
低温超导探测器基于热信号实现对粒子的能量测量,具有eV量级的能量分辨,相较于传统的半导体探测器,其能量分辨提高了一到两个量级,因此对能量分辨要求高的测量场景十分有利。该探测器同时具有无死层、吸收材料选型广泛、掺杂不敏感等特点,这也为实验测量带来了新的思路。本报告简要介绍国内该类探测器的发展现状,之后通过该探测器以铅210的能谱测量为例介绍该探测器在核素4Pi能谱测量方面的潜在应用。本报告最后针对该探测器特点,分析它在中子衰变末态束缚态测量方面的应用可能性。
Nuclear reactor safeguard, based on detection of electron antineutrino flux and energy
spectrum, is of great interests to both administrative agencies such as International Atomic Energy
Agency (IAEA) and neutrino community. A dominant reaction channel of such detection is inverse
beta decay (IBD), for which discrimination of gamma against neutron is critical. In this study, pulse
shape discrimination (PSD) is used over plastic scintillator, for its ease of detector assembly, no risk
of leakage, and high chemical stability. Using 22Na and 137Cs radioactive sources to calibrate the
energy response of the whole system (data acquisition and materials), EJ200 and EJ426 scintillator
combination is used as the discrimination setup. The figure of merit (FOM) can reach 9.13 ± 0.01,
and could be adopted to build a reactor neutrino safeguard detector. In addition, the PSD of two
kinds of plastic scintillators were compared. The FOM of the EJ276 plastic scintillator can reach
1.35 ± 0.01 at the energy threshold of 1 MeV gamma equivalent in comparison to 0.96 ± 0.01 of
UPS-113NG at the same energy threshold.
The Circular Electron Positron Collider (CEPC) is a large international scientific facility proposed by the Chinese particle physics community. The proposal of silicon photomultiplier (SiPM) coupling with the glass scintillator as the detection unit HCAL is a new solution for the next generation calorimeter. In order to achieve the goal of high density and high light yield of the glasses. Glass Scintillators R&D; Group has prepared and researched a large number of scintillating glasses. Among them, the highest light yield can reach 1600 photons/MeV, and the best energy resolution is 19.64%@662keV.Further improvements in light yield and exploration of high-density glass systems are the next phase of the plan.
研究基本粒子性质及相互作用是当今物理学发展的前沿领域之一。近年来,国际上提出直线对撞及环形对撞等多种方案,如ILC(Internationale Linear Collider),FCC-ee(Future Circular Collider-ee) 等正负电子对撞机项目。国内高能物理界提出可研究Higgs物理和Z物理的环形正负电子对撞机(Circular Electron Positron Collider, CEPC)概念设计,物理目标对径迹探测器的设计和优化提出了严格的要求,不断提高的物理需求对径迹探测器性能提出更高的技术需求,时间投影室(Time Projection Chamber, TPC)是核心径迹探测器的一个重要选项。目前国内外已经开展了面向100微米($\sigma$)精度需求的探测器模块相关研究,在解决高分辨及正离子反馈问题的同时,需要实现相关参量的原型机实验研究,基于以上物理问题,通过时间投影室模块、原型机的实验研究,分析解决关键的技术和物理问题。
本报告面向正负电子对撞机物理的时间投影室径迹探测技术(TPC)研究进展,以目前时间投影室研究中的热点问题为切入点,对正离子反馈引起的空间电荷效应、空间位置畸变、长径迹动学空间下的粒子鉴别能力、探测器畸变校正等问题进行了研究。研究首先利用了Mokka 和Comsol 分析研究了在不同亮度和反馈离子数下,空间电荷效应对于空间位置的影响。结合相关的实验研究,得出读出模块保证正离子反馈的定量关系。为了实现正负电子对撞机物理的时间投影室径迹探测物理目标,研究利用266nm激光研究了实验投影室原型机的激光径迹重建、空间点及径迹位置分辨率,分析了电离能损分辨率和漂移速度测量及电场畸变修正方法。并通过全尺寸TPC 电离能损分析测试结果得出:对应于一个最小电离粒子测量,该220个空间点的全尺寸时间投影室的𝑑𝐸/𝑑𝑥 分辨率可以达到3.6%,并且位置分辨率可以达到$\mathcal{O}$(<100$\mu$m) (2T);为面向更高对撞亮度的物理需求,以及粒子鉴别(Particle Identification Detection, PID)的物理需求,同时与LCTPC(International Linear Collider Time Projection Chamber Collaboration)国际合作组,本报告也给出像素型读出时间投影室径迹探测技术(TPC)实验研究进展现状。
To understand the nature of vector charmonium and charmonium-like states better, the measurements of the cross-section of e+ e- -> pi+ pi- J/psi, e+ e- -> K+ K- J/psi, e+ e- -> pi+ pi- psi2(3823), e+ e- -> D+ D- and e+ e- -> D*+ D- are performed at BESIII recently. This talk will include the new decay modes of the well-known resonance, such as Y(4230), and the new observed structures that strongly coupled to these channels.
Using 980 fb-1 of data on and around the Υ(nS)(n=1,2,3,4,5) resonances collected with the Belle detector at KEKB, the two-photon process γγ-> γψ(2S) is studied from √s = 3.7 GeV to 4.2 GeV for the first time. Two structures with resonance parameters being measured are seen in the invariant mass distribution of γψ(2S). And the cross section of e+e- ->ηϕ via initial-state radiation are measured from threshold to 3.95 GeV. The resonant parameters of ϕ(1680) and the branching fraction of ϕ(1680)→ηϕ are also measured in this work.
With the worldly largest psi(2S) samples collected at BEESIII, systematic studies of the decays of eta_c(2S) are performed. As an example, the observation of the decay eta_c(2S) -> 3 (pi+ pi-) will be reported in this talk. Based on the 450M psi(2S) samples, the mass and width of h_c are updated as well as the branching fraction of psi(2S) -> pi0 h_c. In this talk, search for new hadronic decays of h_c and observation of h_c -> proton anti-proton eta will be reported too. And the upper limit of h_c -> pi0 J/psi will be provided. This analysis utilizes the electron-positron collision data at the energy regions above 4 GeV.
We have studied color-octet contributions for $J/\psi$ inclusive production at B factories, i.e., $e^+e^-\to J/\psi({^{3}\hspace{-0.6mm}P_{J}^{[8]}},{^{1}\hspace{-0.6mm}S_{0}^{[8]}}) + X_{\mathrm{non}-c\bar c}$, using the soft gluon factorization (SGF) approach, in which the $J/\psi$ energy spectrum is expressed in a form of perturbatively calculable short-distance hard parts convoluted with one-dimensional soft gluon distributions (SGDs). The series of velocity corrections originated from kinematic effect can be naturally resummed in this approach. Short-distance hard parts have been calculated analytically to next-to-leading order in $\alpha_s$. Renormalization group equations for SGDs have been derived and solved, which resums Sudakov logarithms originated from soft gluon emissions. Our final result gives a upper bound for color-octet matrix elements consistent with that extracted from hadron colliders. This may relieve the well-known universality problem in the NRQCD factorization.
As a comparison, we also analytically calculated short-distance hard parts in the NRQCD factorization, with Sudakov logarithms resummed by using soft collinear effective theory. The comparison shows that velocity corrections from kinematic effect, which have been resummed in SGF, are significant for phenomenological study. Furthermore, it is found that Sudakov logarithms originated from soft gluon emissions are very important, while it is not the case for Sudakov logarithms originated from jet function. Therefore, the partial Sudakov resummation in SGF has already captured the main physics.
Weakly-Interacting-Massive-Particles (WIMPs) are a large class of viable dark matter candidates. We employ heavy particle effective field theory to compute general heavy electroweak multiplets and nucleon elastic scattering up to heavy mass $1/M$ order.
For certain electroweak multiplets, leading order effective theory calculation shows a generic amplitude-level cancellation that yields a severe suppression of the cross section for WIMP-nucleon scattering,
leaving them robust candidates surviving current direct detection experimental sensitivities.
We here perform computation for arbitrary electroweak representations for
all spin-0, spin-1/2, spin-1 and spin-3/2 heavy particles, combining contributions from perturbative QCD and nuclear effects
by state-of-the-art chiral effective theory calculations, and obtain a comprehensive and model-independent WIMP-nucleon benchmark cross section and
WIMP-nucleus direct detection event rate.
We discuss the axion objects such as axion mini-clusters and axion clouds around spinning
black holes, which induce parametric resonances of electromagnetic waves through the
axion-photon interaction, as well as high frequency gravitational waves through gravitational Chern-Simons (CS) coupling. We also present some new detection schemes for axions and high frequency waves.
We propose to search for a heavy neutral lepton (HNL), that is also
known as sterile neutrino, in electron colliders running
with the center-of-mass energies at few GeV, including BESIII, Belle II,
and the proposed Super Tau Charm Factory (STCF). We consider the HNL
interacting with Standard Model neutrino and photon via a transition
magnetic moment, the so-called dipole portal. We use the monophoton
signature at electron colliders to probe the constraints on the
active-sterile neutrino transition magnetic moments $d$ as the function of
the HNL's mass $m_{N}$. It is found that BESIII, Belle II and STCF can
probe the upper limits for $d$ down to $1.3 \times 10^{-5}\
\text{GeV}^{-1}$, $8 \times 10^{-6}\ \text{GeV}^{-1}$, and $1.3 \times
10^{-6}\ \text{GeV}^{-1}$ with $m_{N}$ around GeV scale, respectively, and
have sensitivity to the previously unexplored parameter space for electron-
($d_{e}$) and tau-neutrino ($d_{\tau }$) dipole portal with $m_{N}$ from
dozens to thousands MeV. On $d_{\mu }$ for HNL mixing
with the $\mu$-neutrino, Belle II and STCF can also provide leading
constraints.
中微子质量问题是粒子物理标准模型现有的重大问题之一。利用含有右手中微子的跷跷板机制可以解释该问题,同时右手中微子又可以通过轻子生成机制解释宇宙正反物质不对称,因此寻找右手中微子是一个极具吸引力的课题。然而,对撞机实验在框架下无法直接寻找到右手中微子检验跷跷板机制。我们基于模型,研究了该模型额外的右手中微子产生通道。利用其独特的长寿命粒子信号,我们进行了对撞机唯象学分析,发现在一定参数空间内,可以成功检验跷跷板机制。与此同时,额外的右手中微子产生通道在轻子生成机制中,能够产生强烈的冲刷项,大大减少产生的正反物质不对称。所以对撞机寻找该通道也能够检验轻子生成机制。
By adopting a non-relativistic (NR) reduction method, we study the one-fermion matrix elements between the fermion-gravity and the fermion-photon interactions in the presence of the minimal Lorentz-violating (LV) fermion coefficients. We prescribed the Lense-Thirring (LT) metric with the test particle assumption, as this metric is essentially curved and may demonstrate some novel LV matter-gravity couplings beyond the conventional test of equivalence principle.
With some bold but reasonable assumptions, we get a LV spin-gravity interaction Hamiltonian,
from which we derive the LV corrected spin precession and gravitational acceleration.
With some ad hoc assumptions, we get some very rough bounds on several LV
coefficients, such as $|3\vec{\tilde{H}}-2\vec{b}|\leq1.46\times10^{-5}\mathrm{eV}$,
from those spin-gravity measurements like the Gravity Probe B (GPB).
The energy correlators measure the pattern of the energy deposition in detectors. The collinear limit, where the angle between the detectors approaches zero, is of particular interest for describing the substructure of jets produced at colliders. By utilizing our factorization theorem and calculating the required ingredients, we perform the resummation of the logarithmically enhanced terms for the projected three-point energy correlator in the collinear limit through to NNLL by renormalization group evolution.
The ratio between the projected three-point energy correlator and the two-point energy correlator is an observable advantageous in extracting the strong coupling constant at colliders. We present the NNLL+NNLO perturbative result for this ratio, and consider the effects from power-suppressed non-perturbative QCD corrections. Such an observable with high accuracy may also probe non-trivial information of the jet-substructure and improve our understanding of QCD dynamics.
Precision charmed hadron spectroscopy helps in understanding how the matter is made around us. The large data sample accumulated by the Belle experiment at the KEKB asymmetric-energy e+e− collider provides us a unique opportunity to perform these studies. We report recent results on charmed baryon spectroscopy from Belle, which include measured branching fraction of (newly discovered) decays of Lambda_c, Xi_c and Omega_c, the evidence of Lambda_c(2910), and the CPV studies in charmed baryon sector, etc.
A charmed baryon with strange quark, Xic(2930), was found in the B- -> Lc Lcbar K- decay at B-factories, yet the study of Lc K- pairs produced directly in pp collisions at LHCb finds two baryon states, Xic(2923) and Xic(2939), at this mass region. These two states are confirmed by a recent study of B- -> Lc Lcbar K- at LHCb using pp collision data at 13 TeV. Other features in the Lc K- mass spectrum are also studied. The relative branching fraction of the channel is reported with respect to B -> DDK
At BESIII, the electromagnetic form factors (EMFFs) and the pair production cross sections of various baryons have been studied. The proton EMFF ratio |GE/GM| is determined precisely and line-shape of |GE| is obtained for the first time. The recent results of neutron EMFFs at BESIII show great improvement comparing with previous experiments. Cross sections of various baryon pairs (Lambda, Sigma, Xi, Lambdac) are studied from their thresholds. Anomalous enhancement behavior on the Lambda and Lambdac pair are observed.
With the large datasets on 𝑒+𝑒−-annihilation at the 𝐽/𝜓 and 𝜓(3686) resonances collected at the BESIII experiment, multi-dimensional analyses making use of polarization and entanglement can shed new light on the production and decay properties hyperon-antihyperon pairs. In a series of recent studies performed at BESIII, significant transverse polarization of the (anti)hyperons has been observed in 𝐽/𝜓 or 𝜓(3686) to ΛΛ ̄ , ΣΣ ̄ , ΞΞ ̄, and Ω - anti- Ω + and the spin of Ω− has been determined model independently for the first time. The decay parameters for the most common hadronic weak decay modes were measured, and due to the non-zero polarization, the parameters of hyperon and antihyperon decays could be determined independently of each other for the first time. Comparing the hyperon and antihyperon decay parameters yields precise tests of direct, Δ𝑆 = 1 CP-violation that complement studies performed in the kaon sector.
Weak radiative hyperon decays, important to test the strong interaction and relevant in searches for beyond the standard model physics, have remained puzzling both experimentally and theoretically for a long time. The recently updated branching fraction and first measurement of the asymmetry parameter of $\Lambda\to n\gamma$ by the BESIII Collaboration further exacerbate the issue, as none of the existing predictions can describe the data. We show in this letter that the covariant baryon chiral perturbation theory, with constraints from the latest measurements of hyperon non-leptonic decays, can well describe the BESIII data. The predicted branching fraction and asymmetry parameter for $\Xi^-\to\Sigma^-\gamma$ are also in agreement with the experimental data. We note that a more precise measurement of the asymmetry parameter, which is strongly constrained by chiral symmetry and related with that of $\Sigma^+\to p\gamma$, is crucial to test Hara's theorem. We further predict the branching fraction and asymmetry parameter of $\Sigma^0\to n\gamma$, whose future measurement can serve as a highly nontrivial check on our understanding of weak radiative hyperon decay and on the covariant baryon chiral perturbation theory.
Measuring the properties of hadrons in the non-perturbative QCD energy region is one of the powerful tools to understand the hadron structure and strong interaction. We propose to measure the spatial extent of intermediate baryon resonances and of hadron reaction volume in the non-perturbative QCD energy region. A new method is developed to measure the spatial extent of the $\Delta$(1232) resonance involved in the sequential decay process $γp→π^0 \Delta^{+}→π^0 π^0 p$. The information on the size is given by investigating the Bose-Einstein correlation of these two $\pi^0$s. The experiment is carried out at LEPS2 beam line in Spring-8 with the electromagnetic calorimeter BGOegg of nearly 4π coverage which enables an unprecedented high-resolution measurement, providing precise data for $\pi^0\pi^0$ relative momenta. In addition, s-channel resonance contributions coupling to $\pi^0\pi^0p$ are weak in the photon-beam energy region of 1.3-2.4 GeV, opening the possibility of selecting a clean sample for examining $\pi^0\pi^0$ correlations.
本文基于高速波形采样方法研究了CLYC、CLLB、塑料闪烁体等中子伽马多模探测器的性能。使用Cs137、Am-Be中子源和加速器单能中子源测试了其用于中子伽马识别、热中子注量探测、快中子能谱探测以及伽马能谱探测方面的性能,并实现了对中子、伽马注量率和能谱的同时探测。结果表明在0.1-10 MeV范围内,CLYC和CLLB均具有良好的线性并具有较好的能量分辨率,其中CLYC在662 keV的能量分辨率约为4%。CLYC探测器表现出了最优的综合性能,对于Am-Be中子源,CLYC识别中子、伽马的优值因子(FOM)达到2.5,对热中子的能量分辨率优于4%。CLYC探测器可通过35Cl(n,p)35S反应实现对快中子的探测,实验研究了CLYC在1.4 - 5.2 MeV单能中子入射时的响应,发现其具有良好的线性,可用于快中子的能谱探测,快中子峰的饱和因子(Quenching factor)为0.9,并表现出了良好的中子伽马识别能力,FOM值大于1.3。而CLLB晶体和塑料闪烁体在快中子输入下的FOM值为1.1和1.0,性能差于CLYC晶体。基于卷积神经网络方法,可实现对高计数率下复杂堆积信号类别的判断,结果表明神经网络算法对n、g、n+g、n+n脉冲的误判率小于1%,对于g+g和g+n脉冲的误判率小于3.6%,可给出远多于特征量算法的额外信息,具有较大的应用潜力和价值。
研制成两种结构的含有10B2O3的微通道板成像探测器,即真空密封结构和敞开式结构,两者均采用含10B2O3的微通道板作为中子转换和较低增益的电子倍增,随后采用高增益微通道板来倍增前者的电子,采用超短余辉的P46荧光屏来实现成像,而真空密封结构采用石英玻璃作为窗口,在其上蒸镀多碱阴极,按照微光像增强器的工艺制作,由此可以确保倍增和成像系统质量合格,采用P46的荧光粉,为后续高速相机采集成像数据奠定技术基础。
基于声子探测的新型荧光-热量双读出低温晶体量热器是近年新发展起来的革命性探测技术,具有极高的灵敏度,极低的探测器阈值(20eV),极好的能量分辨(FWHM 5keV@2615keV),独特的粒子鉴别能力,在低本底实验、稀有物理衰变中有广泛的应用前景。报告主要介绍在科大研制钼酸盐低温晶体量热器,在10mK深冷环境下,通过半导体声子传感器及科大自主研制的初级低温低噪声小信号电子学系统,成功读出宇宙线能量沉积产生的荧光-热量二维信号;及其后续优化升级计划,以期获得高性能低温晶体量热器及地面深冷测试平台。
利用电子加速器光中子源来开展融合中子与X射线的双模成像已被证明是一种可行的方法。在已有的技术方案中,我们采用基于“nMCP+闪烁屏+CMOS”的方案来测量中子图像,成功获得了中子/光子融合图像并实现了双模物质识别,但同时也注意到了该探测方案所遇到的两个技术困难:(1)X射线脉冲对中子探测的干扰和(2)探测器级联过程导致的统计性恶化。为此,研究了基于event-count模式的nMCP探测器来开展光中子成像的问题,通过设置优化的实验条件,在强X射线干扰场下,得到了信本比较高的中子图像,可在相对更短的时间内获得更好的图像质量,为基于event-count模式nMCP探测器的双模成像方法奠定了基础。本报告将对光中子成像的技术原理和nMCP探测器的成像方法开展介绍。
为了满足HERD项目研制中探测器性能标定需求,基于闪烁光纤和硅光电倍增管设计了大面积宇宙线测试平台,开展了原理样机研制并进行了初步的性能测试。首先进行了单根光纤性能研究,测试了不同反射材料和耦合方式下的光纤读出信号分布,优选了光输出高的光纤处理方案,并研究了国产SiPM的性能。三层直径1mm的闪烁光纤交错排列构成宇宙线灵敏层,入射宇宙线穿过闪烁光纤阵列并在其中沉积能量产生闪烁光信号。硅光电倍增管拼接成长条阵列用于读出闪烁光纤的输出信号,单片硅光电倍增管面积为3mm*3mm,包含3路读出通道。完成了宽度5cm长度100cm的闪烁光纤阵列研制以及10片SiPM3路读出通道阵列研制,光纤板和SiPM通过硅油耦合组装完成第一个原理样机。利用两台DT5742搭建了32路波形采样测试数据获取系统,对原理样机进行了数据采集。对该原理样机利用宇宙线进行了MIP探测效率测试,MIP信号在SiPM通道产生的信号大于10个光电子,能有效和SiPM的暗噪声进行区。经过分析得到该样机沿着光纤长度方向MIP探测效率均大于99%,能很好满足应用需求。
Observations of Vector Boson Scattering processes (VBS) are one of the major achievements of EWSB and Higgs unitarization mechanism studies at LHC Run2. This talk will bring the latest news from LHC in VBS observations and highly evident measurements, as well as the bridge to new physics portal utilizing such scattering final states.
未来电子对撞机将带来前所未有的精确实验结果,这有助我们加深对标准模型的理解以及寻找新物理。为了给出高精度理论预言,我们需要将微扰论计算推进到更高阶,其核心在于费曼积分的计算。我会在报告中介绍当前计算费曼积分的主流方法、发展以及在物理过程中的应用。
在过去二十年里,现代散射振幅理论发展了许多新的方法,在计算和理解量子场论中与散射过程相关的可观测量方面也得到了许多新的结果,它们为许多高能物理现象提供了更为精确的理论预言与解释。而近些年,起源于上个世纪S-matrix program思想的自举(bootstrap)方法,在计算场论中的物理量方面有一些重要的进展。要计算量子场论中的物理量,往往需要大量极其繁琐的中间步骤,而最终结果有时是极其简单的。因此,自举方法的主要思想,便是通过合适地假设具有一般形式的结果,再利用一些已知的物理约束,直接限定得到最终结果,从而省去了不必要的中间过程。除此之外,不同理论往往满足一些普适的物理约束,这能用于解释不同理论结果之间的唯一性,例如最大超越度原理。这一原理是指,在最大超对称杨-米尔斯理论(N=4 SYM)和量子色动力学理论(QCD)中,对于一类物理量,如反常量纲、形状因子的圈图修正等,其最大超越度部分是相同的。本次报告将介绍利用基于主积分(master integral)的自举方法计算量子场论中的两圈四点形状因子的相关进展,我们使用利用了红外发散、共线因子化、非物理极点消除、幺正性等物理约束,得到了形状因子的圈图修正中最大超越度部分的结果。由于这些物理约束具有一定意义上的一般性,因此它们也可以用于讨论最大超越度原理。
The first observation of the electroweak (EW) production of a Z boson, a photon, and two forward jets (Z$\gamma$jj) in proton-proton collisions at a center-of-mass energy of 13 TeV is presented. A data set corresponding to an integrated luminosity of 137 fb$^{-1}$, collected by the CMS experiment at the LHC in 2016-2018 is used. The measured fiducial cross section for EW Z$\gamma$jj is $\sigma_{\mathrm{EW}}=5.21\pm0.52\,(\mathrm{stat}) \pm 0.56\,(\mathrm{syst})\,\mathrm{fb}=5.21\pm0.76\,\mathrm{fb}$. Single-differential cross sections in photon, leading lepton, and leading jet transverse momenta, and double-differential cross sections in $m_{\mathrm{jj}}$ and $|\Delta\eta_{\mathrm{jj}}|$ are also measured. Exclusion limits on anomalous quartic gauge couplings are derived at 95\% confidence level in terms of the effective field theory operators $\mathrm{M}_{0}$ to $\mathrm{M}_{5}$, $\mathrm{M}_{7}$, $\mathrm{T}_{0}$ to $\mathrm{T}_{2}$, and $\mathrm{T}_{5}$ to $\mathrm{T}_{9}$.
Energy Correlators (EEC) have recently received great interest both theoretically and experimentally. In particular, the study of EECs in jet substructure has gained deeper understanding with the advent of the light-ray operator product expansion. In this talk, based on this progress, we propose a ratio observable named “celestial non-gaussianity”, which roughly is the ratio between three-point energy correlator and a product of two-point correlators. The underlying motivation for such a construction is to probe how the three-point function deviates from the factorization into a product of two-point functions in the squeezed limit. One salient feature of the “celestial non-gaussianity” is its robustness to hadronization effects. We compare our perturbative prediction with CMS Open Data finding good agreement. We anticipate the celestial non-gaussianity and its possible generalizations will be helpful for future precision measurement of effects like spin correlations and the development of parton showers.
对于 muon 成像而设计的光纤闪烁体探测器需要上千的电子学读出 channels,针对该问题,设计一套无触发的
多板同步数字获取(DAQ)系统,其单板 ADC 可搭载 4 片64 通道的 sigma delta ADC,其过采样的方法,以及内嵌的数字整形滤波模块帮助更好的还原模拟信号,这里将对该 ADC 性能进行测试,包括 ENOB,SFDR 等,并与官方结果比较。数字化信号由 FPGA 接收,并借助 SFP+ 接口与 PC 端形成交互。为解决多板同步问题,对于数字化前端部分,通过设计时钟板为整个 DAQ 系统提供同源时钟;对于后端,方法是 FPGA 内部实现对数字信号的解码以及通过 self-trigger 算法对有效信号进行判选,通过加入时间戳的方式实现多板 FPGA 上传 PC 端的同步。最后,在 server 端将数据包拆分,实现数据同步。在 PandaX-4T 中,由于信号源数据有较大的带宽输入,导致在 server 端调用内存对数据包进行接收排序的时候出现拥堵,这里将在 FPGA 端加入修正,用首尾标记(HTM)方法缩小数据包大小,减小 server 的内存调用压力, 实现系统多板同步。
Pion and Kaon Distribtuion Amplitudes from Lattice QCD
This talk contains two parts, the first part is Partonic Collinear Structure by Quantum Computing and the second part is Exploring Light-Cone Distribution Amplitudes from Quantum Computing.
In the first part, we present a systematic quantum algorithm, which integrates both the hadronic state preparation and the evaluation of the real-time light-front correlators, to study parton distribution functions (PDFs). As a proof of concept, we demonstrate the first direct simulation of the PDFs in the 1+1 dimensional Nambu-Jona-Lasinio model. We show the results obtained by numerical diagonalization and by quantum computation using classical hardware. The agreement between these two distinct methods and the qualitative consistency with QCD PDFs validate the proposed quantum algorithm. Our work suggests the encouraging prospects of calculating QCD PDFs on current and near-term quantum devices. The presented quantum algorithm is expected to have many applications in high energy particle and nuclear physics.
For the second part, light-cone distribution amplitudes (LCDAs) are essential nonperturbative quantities for theoretical predictions of exclusive high-energy QCD processes. We demonstrate the prospect of calculating LCDAs on a quantum computer by applying a recently proposed quantum algorithm, with Staggered fermions, to the simulation of the LCDA in the 1+1 dimensional Nambu-Jona-Lasinio model on classical hardware. The agreement between the quantum simulation and the numerical diagonalization justifies the proposed quantum algorithm. In addition, we find that the resulting LCDA exhibits features shared with the LCDAs in QCD.
Dyson-Schwinger 方程 (DSEs) 已被广泛地应用于轻+轻、轻+重和重+重介子性质的研究。基于此方法,我们对轻+重介子的每个半轻衰变的形状因子和衰变宽度进行了计算,包括 B_((s))→π(K), D_s→K; D→π,K, K→π 和 B_c→η_c, 𝐽/𝜓。在这些计算中,我们的结果定量地与现有数据一致,并分析了迄今未测量的 D_s→K^0, B ̅s→K^+形状因子。分析给出|𝑉𝑐𝑠 | = 0.974(10),并预言了赝标量介子的所有分支分数比,如B_c→η_c, 𝐽/𝜓 的分支分数比,即𝜏和𝜇末态分支比的比值: R(η_c )= 0.313(22)和R_(J/ψ)= 0.242(47),可以探讨轻子味道的普适性问题。我们的分析证实了标准模型对 R_(J/ψ) 的预言与唯一的实验结果之间存在2𝜎的差异,需要实验进一步验证。
$\gamma W$ -box图修正是电弱辐射修正中对强子尺度敏感的唯一项, 且对强子尺度敏感. 我们组将格点QCD引入$\pi$介子的辐射衰变修正计算中, 在计算中结合格点理论和微扰论, 将理论计算的不确定度降低为原来的1/3. 此外, 这一计算方案还可以在味SU(3)极限下推广到K介子衰变的辐射修正的计算中. 结合手征微扰论, 我们的计算方案可以给出又良好不确定度估计的低能有效常数的结果.
我们报告的主要内容是利用格点QCD非微扰地计算含有弱衰变的双重子矩阵元的方法以及初步结果,主要包括质子。近年来无中微子双beta衰变实验备受关注,虽然实验观测大多使用较重的原子核,直接使用格点QCD计算并不现实,但我们计算出的相关双重子弱衰变矩阵元能够以有效场论为桥梁为核多体计算提供2体算符的输入,而这也是目前核多体第一性原理计算中的主要误差来源之一。目前已发表的相关结果比较少,NPLQCD合作组在2017年给出了双质子融合和双中微子双beta衰变的结果,而无中微子双beta衰变方面目前只有pi介子的计算结果。我们目前的得到的$g_A$以及双质子融合矩阵元、双中微子双beta衰变矩阵元的初步结果与前人工作相符,无中微子双beta衰变矩阵元有待进一步研究。
We perform the first simultaneous global QCD analysis of spin-averaged and spin-dependent parton distribution functions (PDFs), including single jet production data from unpolarized and polarized hadron collisions. We critically assess the impact of SU(3) flavor symmetry and PDF positivity assumptions on the quark and gluon helicity PDFs, and find strong bias from these, particularly on the gluon polarization. The simultaneous analysis allows for the first time extraction of individual helicity-aligned and antialigned PDFs with a consistent treatment of uncertainties.
Exotic hadrons have attracted l