相关论文: Pattern speed of main spiral arms in NGC 2997: Est…
In the 60's, Prof. Stroemgren proposed to use space velocities and ages of moderately young stars to compute their places of formation in order to study the spiral structure in the Galaxy. We have extended this idea to very young stellar…
All slightly extended sources were identified on deep K-band maps of 46 spiral galaxies reaching at least K=20.3 mag/arcsec2 at a signal-to-noise level of 3. The galaxies had inclination angles <65 deg and linear resolutions <100 pc with…
Observations in the near-infrared (NIR) allow a detailed study of young stellar clusters in grand-design spiral galaxies which in visual bands often are highly obscured by dust lanes along the arms. Deep JHK-maps of 10 spirals were obtained…
Deep, near-infrared JHK-maps were observed for 10 nearby, grand-design, spiral galaxies using HAWK-I/VLT to study the distribution of young stellar clusters in them and thereby determine whether strong spiral perturbations can influence…
We have searched for corotations (CR) in three Southern grand design spiral galaxies: NGC 1365, NGC 1566 and NGC 2997. We have also introduced a method of quantifying errors in the phase diagram used to detect CR. We established the m=2…
We present optical and IR surface photometry of M99 (NGC 4254) at g, r_S i, J and K'. We also present a K' image of M51 (NGC 5194) for comparison. Fourier decomposition of the disk light reveals that the radial distribution of power depends…
From the Sun, a look at the edge of each spiral arm in our Milky Way (seen tangentially, along the line of sight) can yield numerous insights. Using different arm tracers (dust, masers, synchrotron emission, CO gas, open star clusters), we…
Near infrared (NIR) and optical surface photometric analyses of the dusty galaxy NGC972 are presented. The photometric profiles in the BVRJHK bands can be fitted with a combination of gaussian and exponential profiles, corresponding to a…
The stellar content of the spiral galaxy NGC 247 is investigated. The main sequence turn-off (MSTO) in the inner 12 kpc of the disk corresponds to an age of 6 Myr. A mean star formation rate (SFR) of 0.1 solar masses per year during the…
We use the largest open clusters catalogue in the post-Gaia era to provide the observational view of the Galactic disk. By compiling the physical parameters like age, distance, and kinematic information, we investigate the spatial…
We present optical and IR surface photometry of M51 (NGC~5194) at B~V~R~I~J~K and CO$(2.3\mu )$. These data are used to establish whether K-band ($2.2\mu$) images of spiral galaxies provide reliable maps of stellar surface mass density…
We analyze three nearby spiral galaxies - NGC 1097, NGC 1566, and NGC 3627 - using images from the DustPedia database in seven infrared bands (3.6, 8, 24, 70, 100, 160, and 250 micron). For each image, we perform photometric decomposition…
We present spatially resolved distributions and kinematics of the stars and molecular gas in the central 320pc of NGC1097. The stellar continuum confirms the previously reported 3-arm spiral pattern extending into the central 100pc. The…
We present evidence that some of the compact, luminous, young star clusters recently discovered through images taken with the Hubble Space Telescope (HST) have masses comparable to those of old Galactic globular clusters. The "super star…
We present a first large-scale kinematic map of $\sim$50,000 young OB stars ($T_{\rm eff} \geq 10,000$ K), based on BOSS spectroscopy from the Milky Way Mapper OB program in the ongoing Sloan Digital Sky Survey V (SDSS-V). Using…
We present $B,V,R,J,H,K$ broad--band images of the barred galaxy NGC 1097. The optical and infrared colors maps trace the location of the major dust features. The dust lanes are relatively free of star formation and have low opacity. The…
We present high-resolution, high-sensitivity radio continuum observations of the nearby spiral galaxy NGC 2997 at 332, 616 and 1272 MHz using the Giant Metrewave Radio Telescope (GMRT). The integrated spectrum of this galaxy has a spectral…
We have obtained K-band Multi-Object Spectrograph (KMOS) near-IR spectroscopy for 14 red supergiant stars (RSGs) in the young massive star cluster NGC 2100 in the Large Magellanic Cloud (LMC). Stellar parameters including metallicity are…
More than a dozen young stars host spiral arms in their surrounding protoplanetary disks. The excitation mechanisms of such arms are under debate. The two leading hypotheses -- companion-disk interaction and gravitational instability (GI)…
We analyze optical and near-infrared data of a sample of 11 barred spiral galaxies, in order to establish a connection between star formation and bar/spiral dynamics. We find that 22 regions located in the bars, and 20 regions in the spiral…