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Gas density in the orbital plane of a binary system in the common envelope evolutionary phase. Gas quantities are sampled along the black line (see ApJ 746, 74), revealing the presence of spiral shocks.

AMR Study of the Common Envelope Phase of Binary Evolution

Left: position-velocity diagrams of RW Aur A redshifted and blueshifted jets in [S II] emission line are shown in the upper two panels. Observed (black) and synthetic (red and blue for the redshifted and blueshifted jets, respectively) spectra are compared. Velocity centroids fitted from the observed (discrete symbols) and synthetic (thick lines) line spectra are shown in the lower panel. Right: Cross line-ratio plots obtained from observed (discrete symbols) and synthetic (shaded areas) spectra. The difference in physical conditions of the jets and the match between observations and models can be seen.

RW Aur A from the X-Wind Point of View: General Features

The figure compares between the light curves (>100MeV) of the observation and the theory.

Non-thermal Emissions from Pulsars

Schematic picture of the truncated outer disk separated from the inner disk by a coronal gap, indicating the energy and mass flow in the configuration.

The Existence of Inner Cool Disks in the Low Hard State of Accreting Black Holes

Outer-gap death line on the period vs. derivative period plane. Left: entire parameter space. Right: close-up of the millisecond parameter range.

Death Line of Gamma-ray Pulsars with Outer Gaps

Phase-averaged spectrum of the pulsed emission from the Crab pulsar predicted by the self-consistent outer gap model.

Pulsed Gamma-Ray Emission from the Crab Pulsar

Evolution of the photon index Γ (top panel) and the cutoff energy Ec (bottom panel) with the rotational phase is depicted by the (red) thick solid curve.

Spectral Hardening in the Trailing Peak of Gamma-ray Pulsar Light Curve

Comparisons between the observational intensity maps and the model images calculated from our theory for the galaxy NGC 5248. The left panels, from top to bottom, are B-band, CO (1-0), and K-band observations, respectively, where the K-band map is from HST archival data analyzed by the wavelet method. The right panels are our calculations with the corresponding fields of view, after reversion, projection, and reorientation of the original. The top panels indicate a field of view of 175" (13 kpc), the middle 35" (2.6 kpc), and the bottom 24" (1.8 kpc). The middle right panel has been convolved with the 1.9" x 1.4" synthesized beam shown in the middle left panel.

On the Spiral Structure of NGC 5248: An Analytic Approach

Surface density for single OLR. Spiral waves are excited at 2kpc by a fast bar potential, lying in the horizontal direction. The high density spiral regions would lead to starbust activities as shown in the right panel is when the self-gravity of the disk is introduced.

Evolution and Instability of a Self-gravitating Galactic Gaseous Disk under the Influence of a Fast Rotating Bar Potential

The results suggest that neutron stars in systems characterized by low thermal X-ray luminosities (i.e., SAX J1808-3658 and 1H 1905+000) may be of high mass.

X-ray and Gamma-ray Emissions from Rotation Powered Millisecond Pulsars

It can be seen that the donor can reveal emission lines in the infrared region. Observations of both the continuum and lines in this wavelength region will provide important insight on the thermal state of the donor star and, hence, provide an observational test of the binary evolutionary history of these systems.

Theoretical Spectra of the AM CVn Binary System SDSS J0926+3624: Effects of Irradiation onto the Donor Star

The figures show the number of systems (color coded) for a degree of asymmetry, as measured by K, as a function of the orbital separation, luminosity, mass of the AGB star, and mass of its companion.

The Incidence of Non-spherical Circumstellar Envelopes in AGB Stars

The above figures show the density enhancement of the spiral-onion shell shape (a) in the equatorial plane, (b) in a meridional plane, and (c) as a function of the distance from the system center along +x (red), -y (yellow), -x (green), +y (blue), and z (cyan) axes.

Gravitationally Induced Density Wake of a Circularly Orbiting Object As an Interpretative Framework of Ubiquitous Spirals and Arcs

A schematic sketch of the evolution in star-disk interaction.

Magnetospheric Accretion and Ejection of Matter in Resistive Magnetohydrodynamic Simulations

A schematic view of binary system during the transition from the accretion powered low mass X-ray binary phase to the rotation powered millisecond radio pulsar phase.

On the Transition from Accretion Powered to Rotation Powered Millisecond Pulsars

The Theoretical Institute for Advanced Research in Astrophysics (TIARA) was established in 2004 to provide an integrated program of research and education in theoretical astrophysics. The concept of TIARA was developed to take advantage of the growing body of observational data underlying the origin and evolution of stars and planets, of compact objects, and galaxies in the universe that is being gathered by the astronomical community in Taiwan and elsewhere. In the Institute, forefront theoretical research is carried out on the astrophysics of the formation and structure in the universe in a cooperative effort with the National Tsing Hua University (NTHU). TIARA aims to facilitate the efforts of researchers and the training of future theoretical astrophysicists throughout Taiwan and Asia and to integrate the results of the research into the undergraduate and graduate teaching programs at Taiwan's universities and academic institutions.

Since coming into existence, TIARA has hosted a winter/summer school and 2-4 workshops or topical programs of various scales each year. The level of activities is now similar to that at the Canadian Institute for Theoretical Astrophysics in Toronto, Canada (CITA) and the Kavli Institute for Theoretical Physics in Santa Barbara, California (KITP). The astrophysicists visiting Taiwan through its active visitors program, workshops, and schools, bring forefront research in theoretical astrophysics to both the observational and theoretical groups in the astronomy institutes, physics departments, and ASIAA in Taiwan. Since its establishment, TIARA has become one of the most active theoretical astrophysics institutes in Asia. Through TIARA members at IAA, a total of 186 papers have been published or in press, with 6 more submitted.

Together with the forefront observational facilities being developed by ASIAA, the TIARA programs stimulate interest in astronomy by graduate students at the universities and academic institutions, thus building and maintaining the human resources for future initiatives in theoretical and observational astronomy.

TIARA continues to develop its high performance computation capability to meet the needs of theorists and simulators to address critical scientific questions. To support the demands for numerical modeling and to support data analysis in the ALMA era, numerical simulations involving hydrodynamics, magnetohydrodynamics, astrochemistry, and radiation transfer are being developed through the CHARM program. The comparison of the latest observations and the latest theories in a quantitative manner will be an important TIARA initiative.