Giant magnetic flux jumps in single crystals of Ba0.6K0.4Fe2As2

Giant magnetic flux jumps are observed in magnetic hysteresis loops of Ba0.6K0.4Fe2As2 single crystals. The size of the flux jumps, which appear only at low temperatures (T\u3c4 \u3eK), is so large that it can transform the whole superconducting state into the normal state. The recovery rate to the superconducting state is rather slow, although the superconducting state is almost fully recovered. We show that theoretical predictions based on the adiabatic approach with nonlocal electrodynamics give a good explanation of the flux jumps observed in the single crystals of Ba0.6K0.4Fe2As2

STCF Conceptual Design Report: Volume 1 -- Physics & Detector

International audienceThe Super $\tau$-Charm facility (STCF) is an electron-positron collider proposed by the Chinese particle physics community. It is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of $0.5\times 10^{35}{\rm cm}^{-2}{\rm s}^{-1}$ or higher. The STCF will produce a data sample about a factor of 100 larger than that by the present $\tau$-Charm factory -- the BEPCII, providing a unique platform for exploring the asymmetry of matter-antimatter (charge-parity violation), in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions, as well as searching for exotic hadrons and physics beyond the Standard Model. The STCF project in China is under development with an extensive R&D program. This document presents the physics opportunities at the STCF, describes conceptual designs of the STCF detector system, and discusses future plans for detector R&D and physics case studies

STCF Conceptual Design Report: Volume 1 -- Physics & Detector

International audienceThe Super $\tau$-Charm facility (STCF) is an electron-positron collider proposed by the Chinese particle physics community. It is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of $0.5\times 10^{35}{\rm cm}^{-2}{\rm s}^{-1}$ or higher. The STCF will produce a data sample about a factor of 100 larger than that by the present $\tau$-Charm factory -- the BEPCII, providing a unique platform for exploring the asymmetry of matter-antimatter (charge-parity violation), in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions, as well as searching for exotic hadrons and physics beyond the Standard Model. The STCF project in China is under development with an extensive R&D program. This document presents the physics opportunities at the STCF, describes conceptual designs of the STCF detector system, and discusses future plans for detector R&D and physics case studies