Motivated by the problem of expanding the single-trace tree-level amplitude of Einstein-Yang-Mills theory to the BCJ basis of Yang-Mills amplitudes, we present an alternative expansion formula in gauge invariant vector space. Starting from a generic vector space consisting of polynomials of momenta and polarization vectors, we define a new sub-space as a gauge invariant vector space by imposing constraints on the gauge invariant conditions. To characterize this sub-space, we compute its dimension and construct an explicit gauge invariant basis from it. We propose an expansion formula in this gauge invariant basis with expansion coefficients being linear combinations of the Yang-Mills amplitude, manifesting the gauge invariance of both the expansion basis and coefficients. With the help of quivers, we compute the expansion coefficients via differential operators and demonstrate the general expansion algorithm using several examples.

China

Bo Feng

Xiao-Di Li

Rijun Huang

Expansion of EYM amplitudes in gauge invariant vector space B.F. is supported by Qiu-Shi Funding and the National Natural Science Foundation of China (NSFC) (11935013, 11575156); R.H. is supported by the National Natural Science Foundation of China (NSFC) (11805102), Natural Science Foundation of Jiangsu Province (BK20180724) and ShuangChuang Talent Program of Jiangsu Province

We propose to study the flavor properties of the top quark at the future Circular Electron Positron Collider (CEPC) in China. We systematically consider the full set of 56 real parameters that characterize the flavor-changing neutral interactions of the top quark, which can be tested at CEPC in the single top production channel. Compared with the current bounds from the LEP2 data and the projected limits at the high-luminosity LHC, we find that CEPC could improve the limits of the four-fermion flavor-changing coefficients by one to two orders of magnitude, and would also provide similar sensitivity for the two-fermion flavor-changing coefficients. Overall, CEPC could explore a large fraction of currently allowed parameter space that will not be covered by the LHC upgrade. We show that the c-jet tagging capacity at CEPC could further improve its sensitivity to top-charm flavor-changing couplings. If a signal is observed, the kinematic distribution as well as the c-jet tagging could be exploited to pinpoint the various flavor-changing couplings, providing valuable information about the flavor properties of the top quark.
				

Liaoshan Shi

Cen Zhang

Probing the top quark flavor-changing couplings at CEPC Supported by CNRS via the LIA FCPPL, by the CEPC theory study grant, and by IHEP (Y7515540U1)

Higgs boson production in association with a photon (H+ ) offers a promising channel to test the Higgs boson to photon coupling at various energy scales. Its potential sensitivity to anomalous couplings of the Higgs boson has not been explored with the proton-proton collision data. In this paper, we reinterpret the latest ATLAS H+ resonance search results within the Standard Model effective field theory (EFT) framework, using 36.1 fb−1 of proton-proton collision data recorded with the ATLAS detector at TeV. Constraints on the Wilson coefficients of dimension-six EFT operators related to the Higgs boson to photon coupling are provided for the first time in the H+ final state at the LHC.

Zhijun Liang

Bo Liu

Zhenhui He

Constraining the anomalous Higgs boson coupling in production Supported by the National Natural Science Foundation of China (11875278), Beijing Municipal Science &amp; Technology Commission (Z181100004218003), the National Key Research and Development Program of China (2018YFA0404001), and the Hundred Talent Program of the Chinese Academy of Sciences (Y6291150K2)

The prompt and non-prompt production cross-sections for ψ (2S) mesons are measured using 2.1 fb −1 of pp collision data at a centre-of-mass energy of 7 TeV recorded by the ATLAS experiment at the LHC. The measurement exploits the ψ (2S) → J/ψ (→ μ + μ − ) π + π − decay mode, and probes ψ (2S) mesons with transverse momenta in the range 10 ≤ p T &lt; 100 GeV and rapidity | y | &lt; 2 . 0. The results are compared to other measurements of ψ (2S) production at the LHC and to various theoretical models for prompt and non-prompt quarkonium production.

France

Georges Aad

United States

Brad Abbott

Jalal Abdallah

Samah Abdel Khalek

Azerbaijan

Ovsat Abdinov

Netherlands

Rosemarie Aben

Babak Abi

Maris Abolins

Canada

Ossama AbouZeid

Israel

Halina Abramowicz

Henso Abreu

CERN

Ricardo Abreu

Sweden

Yiming Abulaiti

United Kingdom

Bobby Samir Acharya

Poland

Leszek Adamczyk

David Adams

Jahred Adelman

Germany

Stefanie Adomeit

Tim Adye

Montenegro

Tatjana Agatonovic-Jovin

Spain

Juan Antonio Aguilar-Saavedra

Switzerland

Marco Agustoni

Steven Ahlen

Faig Ahmadov

Italy

Giulio Aielli

Henrik Akerstedt

Torsten Paul Ake Åkesson

Japan

Ginga Akimoto

Russia

Andrei Akimov

Gian Luigi Alberghi

Justin Albert

Solveig Albrand

Argentina

Maria Josefina Alconada Verzini

Martin Aleksa

Igor Aleksandrov

Romania

Calin Alexa

Gideon Alexander

Gauthier Alexandre

Greece

Theodoros Alexopoulos

Muhammad Alhroob

Gianluca Alimonti

Lion Alio

John Alison

Benedict Allbrooke

Lee John Allison

Phillip Allport

John Almond

Alberto Aloisio

Denmark

Alejandro Alonso

Francisco Alonso

Cristiano Alpigiani

Andrew David Altheimer

Barbara Alvarez Gonzalez

Mariagrazia Alviggi

Katsuya Amako

Brazil

Yara Amaral Coutinho

Christoph Amelung

Dante Amidei

Portugal

Susana Patricia Amor Dos Santos

Antonio Amorim

Simone Amoroso

Nir Amram

Glenn Amundsen

Christos Anastopoulos

Lucian Stefan Ancu

Nansi Andari

Timothy Andeen

Christoph Falk Anders

Gabriel Anders

Kelby Anderson

Attilio Andreazza

George Victor Andrei

Xabier Anduaga

Stylianos Angelidakis

Ivan Angelozzi

Philipp Anger

Aaron Angerami

Francis Anghinolfi

Alexey Anisenkov

Nuno Anjos

Alberto Annovi

Ariadni Antonaki

Mario Antonelli

Alexey Antonov

Slovakia

Jaroslav Antos

Fabio Anulli

Masato Aoki

Ludovica Aperio Bella

Rudi Apolle

Giorgi Arabidze

Ignacio Aracena

Yasuo Arai

Juan Pedro Araque

Ayana Arce

Jean-Francois Arguin

Spyridon Argyropoulos

Türkiye

Metin Arik

Aaron James Armbruster

Olivier Arnaez

Vanessa Arnal

Measurement of the production cross-section of ψ (2S) → J/ψ (→ μ + μ − ) π + π − in pp collisions at s $$ \sqrt{s} $$ = 7 TeV at ATLAS