BOTTOM BARYONS(B=-1)∧_b~0=udb,≡_b~0=usb,≡_b~-=dsb,Ω_b~-=ssb

<正>~~     

≡BARYONS(S=-2,I=1/2)≡~0=uss,≡~-=dss

<正>~~     

Ω BARYONS(S=-3,I=0)Ω~-=sss

<正>Ω~-I(J~P)=0(3/2~+)Status:****The unambiguous discovery in both production and decay was by BARNES 64.The quantum numbers follow from the assignment of the particle to the baryon decuplet.DEUTSCHMANN 78 and BAUBILLIER 78 rule out J=1/2 and find consistency with J=3/2.AUBERT.BE 06 finds from the decay angular distributions ofΞ_c~0→Ω~-K~+andΩ_(c~0)→Ω~-K~+that J=3/2;this depends on the spins of theΞ_c~0 andΩ_c~0 being J=1/2,their supposed values.We have omitted some results that have been superseded by later experiments.See our earlier editions.     

∧ BARYONS(S=-1,I=0)∧~0=uds

<正>~~     

迥然不同的pV=nRθ与pV=nRT

理想气体的状态方程ｐＶ＝ｎＲθ,是依据三个实验定律进行热力学理论推导的结果。根据它可以用理想气体实现热力学温标。ｐＶ＝ｎＲＴ是依据实验事实得到的理想气体绝对温标的定义式。两者的物理意义是不相同的。     

∑BARYONS(S=-1,I=1)∑~+=uus,∑~0=uds,∑~-=dds

<正>~~     

超越F=ma

不用说，接受这份殊荣，我十分荣幸。除了为多年来关心物理教育的各种问题而感到乐趣之外，我特别高兴在10年前就致力于AAPT的各种活动。它让我了解在座的许多人的工作，使我谦虚，很清楚，你们中间许多人都有可能象我今天这样站在领奖台上。     

BPS States of D=4 ␣N=1 Supersymmetry

We find the combinations of momentum and domain-wall charges corresponding to BPS states preserving 1/4, 1/2 or 3/4 of D=4 N=1 supersymmetry, and we show how the supersymmetry algebra implies their stability. These states form the boundary of the convex cone associated with the Jordan algebra of 4× 4 real symmetric matrices, and we explore some implications of the associated geometry. For the Wess–Zumino model we derive the conditions for preservation of 1/4 supersymmetry when one of two parallel domain-walls is rotated and in addition show that this model does not admit any classical configurations with 3/4 supersymmetry. Our analysis also provides information about BPS states of N=1 D=4 anti-de Sitter supersymmetry. Received: 6 April 2000/ Accepted: 10 September 2000     

D=2 and D=4 realization of κ-conformal algebra

We describe the generators of-conformal transformations leaving invariant the-deformed d'Alembert equation. For the case D=4 the algebraic structure of the conformal extension of the off-shell spin zero realization of-Poincaré algebra is discussed. Then the D=2 off-shell realization of-conformal algebra for arbitrary spin and its commutation relations are studied.Presented at the 4th Colloquium Quantum Groups and Integrable Systems, Prague, 22–24 June 1995.Supported by KBN grant 2P 302 087 06.     

β=0.45, f=350 MHz Spoke腔的设计

近几年来,低b超导腔(例如spoke型，re-entrant 型,CH型)作为质子或者离子在中低能段的加速结构成为研究的热点.许多实验结果表明spoke腔在低能段是很好的选择,在中能段跟椭球腔相比也很具有竞争实力,为此,北京大学开展了β=0.45,频率为350MHz的spoke型质子超导加速腔研究. 本文详细阐述了这种腔的结构及电磁场的设计,从射频参数Q,r/Q,最大表面电磁场和加速效率的计算结果来看,它具有很好的加速性能.     

SⅡ-SⅠ=SⅢ-SⅡ=…=α”的导出、推广及其应用

某物体做初速度为υ0，加速度为α的匀变速直线运动，用s1、s2、s3、…、sn来表示物体在1、2、3、…、n秒内的位移；用s1、s2、s3、…、sN来表示物体在第一、第二、第三、…、第N秒内的位移,由位移公式和题设知：     

"SⅡ-SⅠ=SⅢ-SⅡ=…=a"的导出、推广及其应用

1 公式的导出 某物体做初速度为v_0,加速度为a的匀变速直线运动,用s_1、s_2、s_3、…、s_n来表示物体有1、2、3、…、n秒内的位移;用s_Ⅰ、s_Ⅱ、s_Ⅲ、…、s_N来表示物体在第一、第二、第二、…、第N秒内的位移.由位移公式和题设知;     

Experimental constraints onJ PC=1−+,I=1, Hybrid mesons

Using data on coherent production of π⁺π⁺π^- systems in π⁺ collisions with nuclei we exclude the existence ofJ ^PC=1^?+,I=1, exotic hybrid mesons with masses below 1.5 GeV and widths greater than 20 MeV, provided that their primary coupling is to πρ systems. Hybrid states with just such properties have recently been predicted from arguments based on QCD sum rules. Our experimental limit is based on Primakoff production of these states, and on an argument using vector dominance to relate their radiative widths to πρ channels. There has been increasing interest of late in the existence of hybrid states, which, in the case of mesons, contain a valence gluon in addition to aq \(\bar q\) pair in a color-octet state [1–5]. The pursuit of spectroscopic gluon degrees of freedom has been strongly motivated by the general QCD picture of hadrons, as well as by many specific calculations based on QCD sum rules, lattice simulations, and more phenomenological approaches such as QCD-bag models. Although much effort, both thoretical and experimental, has been devoted to the spectroscopy of glueballs, for which several candidates exist [6], it has also been realized that hybrid states may be as amenable to discovery, and perhaps less ambiguous to interpretation.     

Design of a β=0.45, f=350 MHz Spoke Cavity

Recently intensive studies have been done on superconducting cavities (e.g. spoke cavity, reentrant cavity, and ch cavity), which are used as accelerating structures in the low and medium energy part of high power high intensity proton or ion accelerators. many experiments have shown that spoke cavity is a good candidate for low energy part. it is also promising to be used for the medium β area. so a β=0.45 spoke cavity is being studied at Peking university. in this paper, the structural and electromagnetic design of a β=0.45, f=350mhz spoke cavity is reported in detail. the calculated rf parameters (e.g. Q, r/Q, peak surface fields and dissipated power) indict a potential of good acceleration.     

The ΔTz = + 1 Gamow-Teller excitation of N = 28 isotones

Results of shell-model calculations of Gamow-Teller strength distributions are presented for ⁵⁰Ti → ⁵⁰Sc, ⁵²Cr → ⁵²V and ⁵⁴Fe → ⁵⁴Mn. The results support the previous shell-model estimates that a large fraction of Gamow-Teller strength is concentrated at low excitation energy in the daughter nuclei. The strength distributions are in fairly good agreement with those of forward-angle cross sections of T₀ + 1 isospin states of the intermediate-energy (p, p') reaction on N = 28 isotones. An estimate of quenching in the T₀ → T₀ + 1 τσ mode transition is attempted. Calculations are performed also for the first 2⁺ and 4⁺ parent states in the context of electron capture at the late stages of stellar evolution.     

f =325 MHz,β=0.52 双柱超导Spoke 腔电磁设计

中国科学院近代物理研究所设计的工作频率为325 MHz、最优β为0.52 的双柱超导Spoke 腔的电磁已经完成。详细地描述了Spoke 基部横截面形状和大小对腔体射频性能的影响,采用了跑道形来取代通常的圆形Spoke 基部截面。从归一化峰值电磁场和分路阻抗两方面出发,比较了横截面为横向跑道和纵向跑道的Spoke 基部。Spoke 基部横截面的形状为横向跑道时能得到较好的射频参数,满足中国ADS(C-ADS) 的工程需求。最后利用CST 粒子工作室对得到的腔体进行了二次电子倍增分析,在工作电压附近不存在二次电子倍增,验证了该腔体形状的可行性。The EM design of a 325 MHz β= 0.52 superconducting double Spoke cavity has been finished at Institute of Modern Physics (IMP), Chinese Academy of Sciences(CAS). In this paper, the optimization of the Spoke base is described in detail. The goal is to minimize the peak surface field and maximize the shunt impedance. The common cylinder is replaced by the racetrack shape for the Spoke base. The transverse racetrack Spoke base can offer a better RF property than the longitudinal racetrack Spoke base, which meet the requirement of the C-ADS. The simulation of multipactor finished by CST Particle Studio is also presented, which gives a promising result that there is no multipactor around working voltage.     

β=0.45,f=350MHz spoke腔高阶模的研究

质子或者离子在中低能段的加速结构是目前研究的热点, 其中许多实验结果表明spoke腔是连接RFQ加速结构和椭球腔加速结构的最具潜力的桥梁. 但是这种新型结构仍然存在许多问题有待解决, 为此, 北京大学开展了spoke型质子加速腔的研究, 完成了β=0.45, 频率为350MHz spoke腔的设计和铜模型腔的加工. 重点对spoke腔高阶模进行了分析, 模拟计算找出了几种危害模式, 并完成了实验测量, 取得了实验测量与模拟计算相一致的结果.     

Quantum interference effects in a multidriven transition Fg=3←→Fe=2

We have theoretically and experimentally studied the quantum coherence effects of a degenerate transition Fg =3←→Fe=2 system interacting with a weak linearly polarized （with σ＋ components） probe light and a strong linearly polarized （with σ＋ components） coupling field. Due to the competition between the drive Rabi frequency and the Zeeman splitting, electromagnetically induced transparency （EIT） and electromagnetically induced absorption （EIA） are present at the different values of applied magnetic field in the case where the Zeeman splitting of excited state Δe is larger than the Zeeman splitting of ground state Δg （i.e.Δe 〉 Δg）.     

△BARYONS(S=0,I=3/2)△~(++)=uuu,△~+=uud,△~0=udd,△~-=ddd

<正>~~     

Spectroscopic parameters of theJ π=1+,T=0 excited6Li level

An analysis of thed- coincidence spectra of the⁷Li(³He, d)⁴He reaction at incident energy of 5.0 MeV and at various detector angles has been carried out. The values of the spectroscopic parameters of theJ =1⁺,T=0⁶Li state at excitation energy of 5.65 MeV have been deduced. The results, considering the experimental errors, do not appear to be dependent on the geometry and are in line with the ones adopted in literature.