Apr 1, 2001
in Chinese Journal of Astronomy and Astrophysics
We present results of MERLIN observations of five compact radio sources at 1.6 GHz, part of a large survey to identify compact symmetric objects (CSOs). We give for the first time MERLIN maps of two sources, 1604+315 and 1751+278. The five observed sources show very compact, unresolved point-like structure, which may imply that they axe good CSO candidates.
The newly observed $\Omega_c(3327)$ gives us a good chance to construct the $\Omega_c$ charmed baryon family. In this work, we carry out the mass spectrum analysis by a non-relativistic potential model using Gaussian Expansion
Method , and the study of its two-body Okubo-Zweig-Iizuka allowed strong decay behavior. Our results imply that the $\Omega_c(3327)$ is good candidate of $\Omega_c(1D)$ sta...
The newly discovered $\eta_1(1855)$ and the previously observed $\pi_1(1600)$ provide us with a good opportunity to study the $J^{P(C)}=1^{-(+)}$ light hybrid nonet. In this work, we use a semirelativistic quark potential model to study the masses of the $J^{P(C)}=1^{-(+)}$ light hybrid states, where the static potential for depicting the confinement force between the quark-antiquak pair in a hybr...
In this work, we study the doubly charmed dibaryon states with the $qqqqcc$ ($q =u, d, s$) configuration. The mass spectra of doubly charmed dibaryon states are obtained systematically within the chromomagnetic interaction model. In addition to the mass spectrum analysis, we further illustrate their two-body strong decay behaviours. Our results suggest that there may be narrow states or even stabl...
AR Scorpii (AR Sco), the only-known radio-pulsing white dwarf binary, shows unusual pulsating emission at the radio, infrared, optical and ultraviolet bands. To determine its astrometric parameters at the radio band independently, we conducted multi-epoch Very Long Baseline Interferometry (VLBI) phase-referencing observations with the European VLBI Network (EVN) at 5 GHz and the Chinese VLBI Netwo...
The electron drift in germanium detectors is modeled making many assumptions. Confronted with data, these assumptions have to be revisited. The temperature dependence of the drift of electrons was studied in detail for an n-type segmented point-contact germanium detector. The detector was mounted in a temperature controlled, electrically cooled cryostat. Surface events were induced with collimated...
We present new upgraded Giant Metrewave Radio Telescope (uGMRT) HI 21-cm observations of the ultra-luminous infrared galaxy IRAS 10565+2448, previously reported to show blueshifted, broad, and shallow HI absorption indicating an outflow. Our higher spatial resolution observations have localised this blueshifted outflow, which is $\sim$ 1.36 kpc southwest of the radio centre and has a blueshifted v...
The East Asian VLBI Network (EAVN) is an international VLBI facility in East Asia and is operated under mutual collaboration between East Asian countries, as well as part of Southeast Asian and European countries. EAVN currently consists of 16 radio telescopes and three correlators located in China, Japan, and Korea, and is operated mainly at three frequency bands, 6.7, 22, and 43 GHz with the lon...
The decay process $\Xi_{b}^{-} \rightarrow pK^{-}K^{-}$ is studied with the final state interaction approach by considering the contributions from the $S$-wave meson-baryon interactions, and also the intermediate state $\Lambda(1520)$ in the $D$-wave. The low-lying resonances $\Lambda(1405)$ and $\Lambda(1670)$ have significant contributions, which are both dynamically generated from the $S$-wave ...
The $e^+e^-\to \omega\eta$ and $e^+e^-\to\omega\pi^0\pi^0$ processes are ideal platforms to search for higher $\omega$ states. Focusing on the observations of two enhancement structures around 2.2 GeV existing in $e^+e^-\to \omega\eta$ and $e^+e^-\to\omega\pi^0\pi^0$ at BESIII, we analyze how the $\omega(4S)$ and $\omega(3D)$ states play the role in the $e^+e^-\to \omega\eta$ and $e^+e^-\to\omega\...