相关论文: Really Cool Stars at the Galactic Center

We present our recent efforts to unveil and understand the origin of massive stars outside the three massive star clusters in the Galactic Center. From our HST/NICMOS survey of the Galactic Center, we have identified 180 Paschen-alpha…

We present the first detailed dissection of the circumgalactic medium (CGM) of massive starburst galaxies at z > 2. Our target is a submillimeter galaxy (SMG) at z = 2.674 that has a star formation rate of 1200 $M_\odot$/yr and a molecular…

We report new results of our search for rare, cool carbon stars located at large distances from the galactic plane. Eighteen new C stars were discovered. Six are remarkable by showing the two peculiarities of a strong infrared excess at 12…

We report preliminary results based on new near-infrared observations of the central stellar cluster of our Galaxy conducted with the infrared spectrometer ISAAC at the ESO VLT UT1 and the MPE speckle camera SHARP at the ESO NTT. We…

The stellar population in the central parsec of the Galaxy is dominated by an old (several Gyr) population, but young, massive stars dominate the luminosity function. We have studied the most luminous of these stars, GCIRS 7, in order to…

We present near-infrared H-, K-, L- and M-band photometry of the Galactic Center from images obtained at the ESO VLT in May and August 2002, using the NAOS/CONICA (H and K) and the ISAAC (L and M) instruments. The large field of view (70" x…

Davies and King have suggested that the bright stars observed on short-period orbits about Sgr A* (``S stars'') are old, low-mass stripped AGB stars rather than young, high-mass main-sequence stars. If the observationally inferred effective…

During the period Aug.23-Sept.24 2003, the INTEGRAL observatory performed an ultra deep survey of the Galactic Center region with a record sensitivity at energies higher than 20 keV. We have analized images of the Galactic Center region…

The evidence for the presence of a concentration of dark matter at the Galactic center is now very compelling. There is no question that the stellar and gas kinematics within 0.01 pc is dominated by under-luminous matter in the form of…

We present infrared spectral indices (1.0-2.3 um) of Galactic late-type giants and red supergiants (RSGs). We used existing and new spectra obtained at resolution power R=2000 with SpeX on the IRTF telescope. While a large CO equivalent…

We reanalyze published kinematic and photometric data for the cool star population in the central 10 pc (240 arcsec) of the Galaxy, while (a) isolating the photometric data appropriate to this population, and (b) properly allowing for…

We present new results from an ongoing survey of carbon-rich asymptotic giant (AGB) stars in the halo of our Galaxy. After selecting candidates primarily through their 2MASS colours, slit spectroscopy was achieved at the ESO NTT telescope.…

While the number of stars in the Galactic bulge with detailed chemical abundance measurements is increasingly rapidly, the inner Galactic bulge ( |b| < 2$^\circ$) remains poorly studied, due to heavy interstellar absorption and photometric…

A massive young star cluster, initially embedded in its parent molecular cloud, will spiral into the Galactic Center from $\lta 30m_6^{1/2}\pc$ during the life-time of its most massive stars, if the combined total mass is $\sim…

Comparison of ISM absorption in the UV spectrum of LS 4825, a B1 Ib-II star d=21+/-5 kpc from the Sun toward l = 1.67 deg and b = -6.63 deg, with ISM absorption toward an aligned foreground star at d < 7.0+/-1.7 kpc, allows us to isolate…

The region bounded by the inner tens of light years at the center of the Milky Way contains five principal components that coexist within the central deep gravitational potential well. These constituents are a black hole candidate (Sgr~A*)…

IRS 7 is an M red supergiant star which is located at $5".5$ north of Sagittarius A$^\ast$. We detected firstly the continuum emission at 340 GHz of IRS 7 using ALMA. The total flux density of IRS 7 is $S_\nu=448\pm45 \mu$Jy. The flux…

We report the discovery of 19 hot, evolved, massive stars near the Galactic center region (GCR). These objects were selected for spectroscopy owing to their detection as strong sources of Paschen-alpha emission-line excess, following a…

We present new proper motion measurements and simultaneous orbital solutions for three newly identified (S0-16, S0-19, and S0-20) and four previously known (S0-1, S0-2, S0-4, and S0-5) stars at the Galactic Center. This analysis pinpoints…

We present results on the nature of extreme ejective feedback episodes and the physical conditions of a population of massive ($\rm M_* \sim 10^{11} M_{\odot}$), compact starburst galaxies at z = 0.4-0.7. We use data from Keck/NIRSPEC,…