Dark matter dominated dwarf disc galaxy Segue 1 (2009)
Xiang-Gruess, Meng, Lou, Yu-Qing, Duschl, Wolfgang J.
Several observations reveal that dwarf galaxy Segue 1 has a dark matter (DM) halo at least ~ 200 times more massive than its visible baryon mass of only ~ 103 solar masses. The baryon mass is...
Global Collapses and Expansions in Star-Forming Clouds (2009)
Spectral molecular line profile observations of star-forming molecular clouds sometimes show distinct red asymmetric double-peaked molecular line profiles with weaker blue peaks and stronger red...
Perturbation Analysis of a General Polytropic Homologously Collapsing Stellar Core (2009)
For dynamic background models of Goldreich & Weber and Lou & Cao, we examine 3-dimensional perturbation properties of oscillations and instabilities in a general polytropic homologously collapsing...
Molecular Line Profiles of Collapsing Gas Clouds (2009)
Gao, Yang, Lou, Yu-Qing, Wu, Kinwah
Emission line profiles of tracer molecule H$_2$CO 140 GHz transition from gravitational core collapsing clouds in the dynamic process of forming protostars are calculated, using a simple ray-tracing...
Dynamic Evolution Model of Isothermal Voids and Shocks (2009)
We explore self-similar hydrodynamic evolution of central voids embedded in an isothermal gas of spherical symmetry under the self-gravity. More specifically, we study voids expanding at constant...
General Polytropic Magnetofluid under Self-Gravity: Voids and Shocks (2009)
We study the self-similar magnetohydrodynamics (MHD) of a quasi-spherical expanding void (viz. cavity or bubble) in the centre of a self-gravitating gas sphere with a general polytropic equation of...
Magnetized massive stars as magnetar progenitors (2009)
The origin of ultra-intense magnetic fields on magnetars is a mystery in modern astrophysics. We model the core collapse dynamics of massive progenitor stars with high surface magnetic fields in the...
Mass and Mean Velocity Dispersion Relations for Supermassive Black Holes in Galactic Bulges (2008)
Growing evidence indicate supermassive black holes (SMBHs) in the mass range of $M_{\rm BH}$$\sim 10^6-10^{10}M_{\odot}$ lurking in central bulges of many galaxies. Extensive observations reveal...
Supermassive Black Holes in Galactic Bulges (2008)
Growing evidence indicate supermassive black holes (SMBHs) in a mass range of $M_{\rm BH}$$\sim 106-10^{10}M_{\odot}$ lurking in central stellar bulges of galaxies.Extensive observations reveal...
Rebound Shock Breakouts of Exploding Massive Stars: A MHD Void Model (2008)
With a self-similar magnetohydrodynamic (MHD) model of an exploding progenitor star and an outgoing rebound shock and with the thermal bremsstrahlung as the major radiation mechanism in X-ray bands,...
Homologous Core Collapse in a Massive Star and Self-Similar Evolution of Rebound Shocks (2008)
During the gravitational core collapse of a massive progenitor star which may give rise to at least a class of gamma-ray bursts (GRBs) associated with supernovae, a stellar core rapidly passes...
Self-Similar Polytropic Champagne Flows in H II Regions (2008)
We explore large-scale hydrodynamics of H II regions for various self-similar shock flows of a polytropic gas cloud under self-gravity and with quasi-spherical symmetry. We formulate cloud dynamics...
Dynamic Evolution of a Quasi-Spherical General Polytropic Magnetofluid with Self-Gravity (2008)
In various astrophysical contexts, we analyze self-similar behaviours of magnetohydrodynamic (MHD) evolution of a quasi-spherical polytropic magnetized gas under self-gravity with the specific...
Self-Similar Shocks and Winds in Galaxy Clusters (2008)
Lou, Yu-Qing, Jiang, Yan-Fei, Jin, Chi-Chuan
A theoretical model framework of spherical symmetry is presented for a composite astrophysical system of two polytropic fluids coupled together by gravity to explore large-scale shocks and flow...
Collisional interaction limits between dark matters and baryons in `cooling flow' clusters (2007)
Presuming weak collisional interactions to exchange the kinetic energy between dark matter and baryonic matter in a galaxy cluster, we re-examine the effectiveness of this process in several `cooling...
Self-Similar Dynamics of a Relativistically Hot Gas (2007)
In the presence of self-gravity, we investigate the self-similar dynamics of a relativistically hot gas with or without shocks in astrophysical processes of stellar core collapse, formation of...
Self-Similar Dynamics of a Magnetized Polytropic Gas (2007)
In broad astrophysical contexts of large-scale gravitational collapses and outflows and as a basis for various further astrophysical applications, we formulate and investigate a theoretical problem...
Magnetohydrodynamic Rebound Shocks of Supernovae (2007)
We construct magnetohydrodynamic (MHD) similarity rebound shocks joining `quasi-static' asymptotic solutions around the central degenerate core to explore an MHD model for the evolution of random...
Self-Similar Shocks in Polytropic Gas Flows around Star-Forming Regions (2006)
Self-similar shock solutions in spherically symmetric polytropic gas flows are constructed and analyzed in contexts of proto-star formation processes. Among other possible solutions, we model a...
New Self-Similar Solutions of Polytropic Gas Dynamics (2006)
We explore semi-complete self-similar solutions for the polytropic gas dynamics involving self-gravity under spherical symmetry, examine behaviours of the sonic critical curve, and present new...
Scale-Free Thin Discs with an Isopedic Magnetic Field (2006)
Global stationary configurations of both aligned and logarithmic spiral MHD perturbations are constructed analytically within an axisymmetric background ofrazor-thin scale-free gas disc, which is...
We investigate a theoretical MHD disc problem involving a composite disc system of gravitationally coupled stellar and gaseous discs with a coplanar magnetic field in the presence of an axisymmetric...
Dispersal of Gaseous Circumstellar Discs around High-Mass Stars (2006)
We study the dispersal of a gaseous disc surrounding a central high-mass stellar core once this circumstellar disc becomes fully ionized. If the stellar and surrounding EUV and X-ray radiations are...
Envelope Expansion with Core Collapse. III. Similarity Isothermal Shocks in a Magnetofluid (2006)
Yu, Cong, Lou, Yu-Qing, Bian, Fu-Yan, Wu, Yan
We explore MHD solutions for envelope expansions with core collapse (EECC) with isothermal MHD shocks in a quasi-spherical symmetry and outline potential astrophysical applications of such magnetized...
We investigate self-similar magnetohydrodynamic (MHD) processes in an isothermal self-gravitating fluid with a quasi-spherical symmetry and extend the envelope expansion with core collapse (EECC)...
Spherical Isothermal Self-Similar Shock Flows (2005)
We explore self-similar dynamical processes in a spherical isothermal self-gravitational fluid with an emphasis on shocks and outline astrophysical applications of such shock solutions. The previous...
Using the fluid-magnetofluid formalism, we obtain axisymmetric stability criteria for a composite disc system consisting of stellar and gaseous magnetized singular isothermal discs (MSIDs). Lou & Zou...
Forming supermassive black holes by accreting dark and baryon matter (2005)
Hu, Jian, Shen, Yue, Lou, Yu-Qing, Zhang, Shuangnan
Given a large-scale mixture of self-interacting dark matter (SIDM) particles and baryon matter distributed in the early Universe, we advance here a two-phase accretion scenario for forming...
We investigate self-similar magnetohydrodynamic (MHD) processes in an isothermal self-gravitating fluid with a quasi-spherical symmetry and extend the envelope expansion with core collapse (EECC)...
Spherical Isothermal Self-Similar Shock Flows (2005)
We explore self-similar dynamical processes in a spherical isothermal self-gravitational fluid with an emphasis on shocks and outline astrophysical applications of such shock solutions. The previous...
The Progenitor of Supernova 2004dj in a Star Cluster (2005)
Wang, Xiaofeng, Yang, Yanbin, Zhang, Tianmeng, Ma, Jun, Zhou, Xu, Li, Weidong, ...
The progenitor of type II-plateau supernova (SN) 2004dj is identified with a supergiant in a compact star cluster known as "Sandage Star 96" (S96) in the nearby spiral galaxy NGC 2403, which was...
We investigate self-similar magnetohydrodynamic (MHD) processes in an isothermal self-gravitating fluid with a quasi-spherical symmetry and extend the envelope expansion with core collapse (EECC)...
Spherical Isothermal Self-Similar Shock Flows (2005)
We explore self-similar dynamical processes in a spherical isothermal self-gravitational fluid with an emphasis on shocks and outline astrophysical applications of such shock solutions. The previous...
We investigate self-similar magnetohydrodynamic (MHD) processes in an isothermal self-gravitating fluid with a quasi-spherical symmetry and extend the envelope expansion with core collapse (EECC)...
Spherical Isothermal Self-Similar Shock Flows (2005)
We explore self-similar dynamical processes in a spherical isothermal self-gravitational fluid with an emphasis on shocks and outline astrophysical applications of such shock solutions. The previous...
Correlations among Multi-Wavelength Luminosities of Star-Forming Galaxies (2004)
It has been known for two decades that a tight correlation exists between far-infrared (FIR) and radio (1.4 and 4.8 GHz) global fluxes/luminosities from galaxies, which may be explained in terms of...
Structures in a class of magnetized scale-free discs (2004)
Shen, Yue, Liu, Xin, Lou, Yu-Qing
We construct analytically stationary global configurations for both aligned and logarithmic spiral coplanar magnetohydrodynamic (MHD) perturbations in an axisymmetric background MHD disc with a...
MHD tidal waves on a spinning magnetic compact star (2004)
In an X-ray binary system, the companion star feeds the compact neutron star with plasma materials via accretions. The spinning neutron star is likely covered with a thin "magnetized ocean" and may...
Outflows and inflows in astrophysical systems (2004)
We seek for self-similar solutions describing the time-dependent evolution of self-gravity systems with either spherical symmetry or axisymmetric disk geometry. By assuming self-similar variable...
Shocked similarity collapses and flows in star formation processes (2004)
We propose self-similar shocked flow models for certain dynamical evolution phases of young stellar objects (YSOs), `champagne flows' of H {\sevenrm II} regions surrounding OB stars and shaping...
Gravitationally coupled scale-free discs (2004)
In a composite fluid system of two gravitationally coupled barotropic scale-free discs bearing a rotation curve $v\propto r^{-\beta}$ and a power-law surface mass density $\Sigma_0\propto...
X-ray triple rings around the M87 jets in the central Virgo cluster (2004)
Feng, Hua, Zhang, Shuang-Nan, Lou, Yu-Qing, Li, Ti-Pei
The Chandra X-ray data of the central Virgo cluster are re-examined to reveal a triple-ring structure around the galaxy M87, reminiscent of the spectacular triple-ring pattern of the SN1987A in the...
In a composite system of gravitationally coupled stellar and gaseous discs, we perform linear stability analysis for axisymmetric coplanar perturbations using the two-fluid formalism. The background...
Magnetic Sunyaev-Zel'dovich effect in galaxy clusters (2004)
This Letter explores influences of intracluster magnetic fields ($\gsim 1\mu$G) submerged in the hot electron gas on classic Sunyaev-Zel'dovich effect (SZE) and thermal bremsstrahlung in X-ray...
We construct aligned and unaligned stationary perturbation configurations in a composite system of stellar and coplanarly magnetized gaseous singular isothermal discs (SIDs) coupled by gravity. In...
Envelope Expansion with Core Collapse. I. Spherical Isothermal Similarity Solutions (2003)
We investigate self-similar dynamical processes in an isothermal self-gravitational fluid with spherical symmetry. In reference to earlier complementary solution results of Larson, Penston, Shu,...
Stationary Nonaxisymmetric Configurations of Magnetized Singular Isothermal Disks (2003)
We construct both aligned and unaligned (logarithmic spiral) stationary configurations of nonaxisymmetric magnetohydrodynamic (MHD) disks from either a full or a partial razor-thin power-law...
Axisymmetric stability criterion for two gravitationally coupled singular isothermal discs (2003)
Using the two-fluid formalism with the polytropic approximation, we examine the axisymmetric stability criterion for a composite system of gravitationally coupled stellar and gaseous singular...
Multi-wavelength observations from radio to soft X-ray bands of large-scale galactic spiral structures offer synthesized and comprehensive views of nearby disk galaxies. In the presence of a massive...
Experiments aboard the Ulysses spacecraft discovered quasi-periodic bursts of relativistic electrons and of radio emissions with ~40-minute period(QP-40) from the south pole of Jupiter in February...
Perturbation configurations in a two-fluid system of singular isothermal disks (2003)
We investigate properties of stationary aligned and unaligned spiral perturbation configurations in a composite system of gravitationally coupled stellar and gaseous singular isothermal disks (SIDs)...
Circumnuclear Spiral Arms and Starburst Rings in Magnetized Barred Spiral Galaxies (2001)
Lou, Yu-Qing, Fan, ZuHui, Yuan, Chi, Leon, Stephane
The Seyfert galaxy NGC 1097 has an extended neutral hydrogen disk, a companion, a prominent bar and a luminous circumnuclear starburst "ring". Magnetic fields as revealed by nonthermal...
Thesis (Ph. D.)--Harvard University, 1987.