Shanghai Jiao Tong University Physics and Astronomy Academic Innovation Forum for Doctoral Students

Session

Poster Session

10 Dec 2021, 15:40

Tsung-Dao Lee Institute

46. Di-boson simulation and precise measurement of Zγ analysis in ATLAS Detector

Danning Liu (TDLI)

10/12/2021, 15:40

Di-boson process is one important test of the Standard Model Electroweak Symmetry Breaking, and also
backgrounds for many new physics searches. The study shows the simulation and precise measurement of di-boson
process in pp collisions at s = 13TeV, using a full dataset corresponding to an integrated luminosity of 139 fb−1
recorded with the ATLAS detector at the LHC. Di-boson process is also...

21. Evaluating the origins of the secondary bias based on the correlation of halo properties with the linear density field

Xiaoyu Wang (USTC)

10/12/2021, 15:40

Using two sets of large $N$-body simulations, we studied the origins of the correlations between halo assembly time ($z_{\rm f}$), concentration ($v_{\rm max}/v_{\rm 200}$), and spin ($\lambda$) with the large-scale evolved density field at given halo mass, namely, the secondary bias. We find that the secondary bias is a secondary effect resulting from the correlations of halo properties with...

47. Gauge-Gravity Duality under Kaluza-Klein Compactification: From String to Field

Mr Yanfeng Hang

10/12/2021, 15:40

The scattering amplitudes of massive Kaluza-Klein (KK) states of open and closed bosonic strings play an important role in studying the duality between the gauge and gravity theories. We analyze the structure of vertex operators for the KK strings and derive an extended massive KLT-like relation which connects the $N$-point KK closed-string amplitude to the products of two KK open-string...

45. Implement NN Pixel Clustering in ATLAS Inner Detector Trigger for b-jet Signature

Mr Zhen Wang (TDLI)

10/12/2021, 15:40

This study has finished the implementation of NN pixel Clustering algorithm of Athena release 22 in the ATLAS Inner Detector Trigger analysis framework for the b-jet signature. An improvement in the tracking efficiency is observed in release 22 offline tracking. The study also helps to improve the tracking efficiency by modifying the truth level tracking information.

48. Optomechanical atomic force microscope

Mr Fei He (SJTU)

10/12/2021, 15:40

In the scanning probe microscope system, the weak signal detection of cantilever vibration is one of the important factors affecting the sensor sensitivity. In our current work, we present a novel design concept for an atomic force microscope (AFM) combined with optomechanics with an ultra-high quality factor and a low thermal noise. The detection system consists of a fixed mirror placed on...

44. Probing environmental quenching in the Fornax cluster through a population-orbital superposition method

Yuchen Ding (Shanghai astronomical observatory)

10/12/2021, 15:40

We probe the effect of cluster environment to the star formation quenching in galactic thin disks for 18 galaxies (17 early-type, 1 late-type) in the Fornax cluster. High quality data resolving the kinematical and chemical information across the observational plane are obtained through IFU observations with MUSE/VLT.  We create population-orbit superposition models to each galaxy, the model...

49. Semi-leptonic 𝑡𝑡 ̅ Calibration for 𝑋→𝑏𝑏 ̅ tagger

Qibin LIU

10/12/2021, 15:40

The identification of massive particles decaying into bottom quark pairs is important for the physics program of the ATLAS experiment at the Large Hadron Collider. A neural network (NN) based double b-tagging algorithm named 𝑋→𝑏𝑏 ̅ tagger is developed and calibrations of the tagger are performed using proton-proton collision data corresponding to 139/𝑓𝑏 collected at a centre-of-mass energy of...

20. Single particle tunneling microscopy and vortex bound states in the layered superconductor KCa2Fe4As4F2

Mr Xiaoyu Chen (Nanjing University)

10/12/2021, 15:40

We perform scanning tunneling microscopy/spectroscopy (STM/STS) study on the layered iron based superconductor KCa2Fe4As4F2 with a critical temperature of about 33.5 K. The commonly obtained surface shows full-gap feature with energy gap values close to 4.6 meV. This type of spectrum presents a uniform full gap in space indicating the absence of gap nodes in this superconductor. Quasiparticle...

43. Sky survey of VHE gamma ray sources with LHAASO-WCDA

Shicong Hu (Institute of High Energy Physics, Chinese Academy of Sciences)

10/12/2021, 15:40

Very high energy (VHE,>100 GeV) gamma-rays open a crucial window to explore the "non-thermal Universe". High-sensitivity, unbiased surveys of the gamma-ray sky are important to find new astrophysical objects - both to understand their bulk properties, and to constrain new physics beyond the standard model. Up to now, more than 230 sources are detected mainly by IACT (like Whipple, HESS, MAGIC...

42. Split Invariant Curves In Rotating Bar Potentials

Ms Tianye Xia (1Department of Astronomy, School of Physics and Astronomy, Shanghai Jiao Tong University )

10/12/2021, 15:40

Invariant curves are generally closed curves in the Poincare ́ surface of section. Here we study an interesting dynamical phenomenon, first discovered by Binney (1985) in a rotating Kepler potential, where an invariant curve of the surface of section can split into two disconnected line segments under certain conditions, which is distinctively different from the islands of resonant orbits. We...

25. 几种镍氧化物块材中超导电性的探索

Dr Qing Li (Nanjing university)

10/12/2021, 15:40

最近，有研究者在几种镍氧化物薄膜 R1-xAxNiO2 (R = La, Pr, Nd; A = Ca, Sr) 中发现了约 5-15 K 的超导电性，这引起了超导和材料相关领域的极大关注。由于其母相 RNiO2 中Ni的 3d9 核外电子排布与铜基高温超导母体极其相似，因此人们认为这两类材料中的超导电性可能具有相同的起源。我们利用高温高压和低温软化学还原相结合的三步合成方法，成功制备了块材 Nd1−xSrxNiO2 (x = 0, 0.2,...

26. 面内旋转磁场下CsV3Sb5的c轴电阻二度对称性的发现

Dr Ying Xiang (Nanjing University)

10/12/2021, 15:40

过渡金属化合物中，因为电荷、自旋、晶格、轨道等自由度之间的相互作用，很多有序态之间具有相似的能量。其中有个常见的态是电子向列相，它的出现破坏了晶体的面内旋转对称性，并经常和其他态共存、互相影响、合作或竞争。而具有kagome晶格的材料包含丰富的奇异电子特性，比如自旋液体、电荷密度波、超导和拓扑态等。最近，新的拓扑kagome金属家族AV3Sb5 (A = K, Rb, or Cs) 被发现，并迅速引起了广泛关注。我们在CsV3Sb5单晶的面内旋转磁场并测量c方向的电阻率，观测到c方向的电阻率无论在超导态还是正常态都具有二度旋转对称性，并且超导态和正常态对应曲线的极值角度方向相互垂直。我们的研究结果为理解CsV3Sb5特殊的物理性质提供了新的思路。