Quantum affine vertex algebras associated to untwisted quantum affinization algebras

Let $\mathcal U_\hbar(\hat{\mathfrak g})$ be the untwisted quantum affinization of a symmetrizable quantum Kac-Moody algebra $\mathcal U_\hbar({\mathfrak g})$. For $\ell\in\mathbb C$, we construct an $\hbar$-adic quantum vertex algebra $V_{\hat{\mathfrak g},\hbar}(\ell,0)$, and establish a one-to-one correspondence between $\phi$-coordinated $V_{\hat{\mathfrak g},\hbar}(\ell,0)$-modules and restricted $\mathcal U_\hbar(\hat{\mathfrak g})$-modules of level $\ell$. Suppose that $\ell$ is a positive integer. We construct a quotient $\hbar$-adic quantum vertex algebra $L_{\hat{\mathfrak g},\hbar}(\ell,0)$ of $V_{\hat{\mathfrak g},\hbar}(\ell,0)$, and establish a one-to-one correspondence between certain $\phi$-coordinated $L_{\hat{\mathfrak g},\hbar}(\ell,0)$-modules and restricted integrable $\mathcal U_\hbar(\hat{\mathfrak g})$-modules of level $\ell$. Suppose further that ${\mathfrak g}$ is of finite type. We prove that $L_{\hat{\mathfrak g},\hbar}(\ell,0)/\hbar L_{\hat{\mathfrak g},\hbar}(\ell,0)$ is isomorphic to the simple affine vertex algebra $L_{\hat{\mathfrak g}}(\ell,0)$

Millimeter line observations toward four local galaxies

We present results of millimeter line observations toward four local gas-rich galaxies (NGC 3079, NGC 4258, NGC 6240 and VII Zw 31) with the IRAM 30 meter millimeter telescope. More than 33 lines in these four sources were detected, including normal dense gas tracers (HCN 1-0, HCO$^+$ 1-0, and C$_2$H 1-0, etc) and their isotopic species. H$^{13}$CN (1-0) and H$^{13}$CO$^+$ (1-0) are detected for the first time in NGC 4258. Optical depths of HCN 1-0 and HCO$^{+}$ 1-0 were estimated with detected isotopic lines in NGC 4258, which were 4.1 and 2.6, respectively. HC$_3$N $J=29-28$, which requires high volume density and high temperature to excite, was detected in NGC 6240. High ratios of HCO$^+$/HCN in NGC 4258 and NGC 6240 imply that this ratio might not be a perfect diagnostic tool between AGN and starburst environments, due to contamination/combination of both processes. The low HC$_3$N/HCN line ratios with less than 0.15 in NGC 4258, NGC 6240 and the non-detection of HC$_3$N line in NGC 3079 and VII Zw 31 indicates that these four galaxies are HC$_3$N-poor galaxies. The variation of fractional abundance of CN in different types of galaxies is large.Comment: 15pages, 13 figures; accepted for publication in MNRA

Experimental Study on the Thermodynamic Damage Power of Ammunition Deflagration in a Closed Explosive Device

The high temperature and high pressure gas produced by propellant deburning has strong thermal effect,which will produce strong thermal damage effect on the target. In this study, an improved closed explosive device was used to simulate the thermal shock loading of 5/7 single base propellant with a charge mass of 17.4 g, and the change law of heat flow density of propellant in the process of deflagration in a closed environment was tested. The experimental results show that the temperature rises rapidly during the deflagration of the 5/7 single-base propellant, and the maximum heat flow density can reach 17.68 MW/ m2 . The curves obtained from the three tests have good consistency in the change trend, which proves the engineering practicability of the improved closed explosive device in the study