Search Publications
From outburst to quiescence: spectroscopic evolution of V1838 Aql imbedded in a bow-shock nebula
Chavushyan, V.; Neustroev, V.; García-Díaz, Ma T. +15 more
We analyse new optical spectroscopic, direct-image and X-ray observations of the recently discovered a high-proper motion cataclysmic variable V1838 Aql. The data were obtained during its 2013 superoutburst and its subsequent quiescent state. An extended emission around the source was observed up to 30 d after the peak of the superoutburst, interp…
A systematic study of ULIRGs using near-infrared absorption bands reveals a strong UV environment in their star-forming regions
Nakagawa, Takao; Baba, Shunsuke; Isobe, Naoki +3 more
We present a systematic study of the 3.0 µm H2O ice and the 3.4 µm aliphatic carbon absorption features toward 48 local ultraluminous infrared galaxies (ULIRGs) using spectra obtained by the AKARI Infrared Camera to investigate the UV environment in their star-forming regions. All the ULIRGs in our sample exhibit a ratio of …
Variable stars in young open cluster NGC 2244
Michalska, Gabriela
We present results of a UBVIC variability survey in the young open cluster NGC 2244. In total, we found 245 variable stars. Most of them, 211 stars, are variables with irregular variations. Furthermore, 23 periodic variables were found. We also detected four candidates for δ Scuti stars and seven eclipsing binaries. Based on the mid-inf…
Chandra Observations of the Massive Star-forming Region Onsala 2
Skinner, Stephen L.; Güdel, Manuel; Sokal, Kimberly R.
Previous radio and infrared observations have revealed an obscured region of high-mass star formation in Cygnus known as Onsala 2 (ON2). Within this region lies the optically revealed young stellar cluster Berkeley 87, which contains several OB stars and the rare oxygen-type Wolf-Rayet star WR 142. Previous radio studies of ON2 have also discovere…
A Sub-damped Lyα Absorber with Unusual Abundances: Evidence of Gas Recycling in a Low-redshift Galaxy Group
Frye, Brenda L.; Bowen, David V.; Tripp, Todd M. +3 more
Using Hubble Space Telescope/Space Telescope Imaging Spectrograph G140M spectroscopy, we investigate an absorption-line system at z = 0.07489 in the spectrum of the quasi-stellar object PG 1543+489 (z QSO = 0.401). The sightline passes within ρ = 66 kpc of an edge-on 2{L}* disk galaxy at a similar redshift, but the galaxy be…
Young star clusters and the structure of the second Galactic quadrant II
Molina Lera, J. A.; Baume, G.; Gamen, R.
Galactic spiral arms are traced using young objects as giant molecular clouds, H II regions, OB stars, or young open/embedded clusters. To improve the knowledge of the Galactic structure in the second quadrant we selected, from more than 200 open clusters covered by the SDSS, a sample of 10 young stellar clusters to conduct a spectrophotometric st…
A study of accretion and disk diagnostics in the NGC 2264 cluster
Alencar, Silvia H. P.; Calvet, Nuria; Sousa, Alana P. +3 more
Context. Understanding disk dissipation is essential for studying how planets form. Disk gaps and holes, which almost correspond to dust-free regions, are inferred from infrared observations of T Tauri stars (TTS), indicating the existence of a transitional phase between thick accreting disks and debris disks. Transition disks are usually referred…
Inquiring into the nature of the Abell 2667 brightest cluster galaxy: physical properties from MUSE
Berta, S.; Popesso, P.; Rodighiero, G. +21 more
Based on HST and MUSE data, we probe the stellar and gas properties (i.e. kinematics, stellar mass, star formation rate) of the radio-loud brightest cluster galaxy (BCG) located at the centre of the X-ray-luminous cool-core cluster Abell 2667 (z = 0.2343). The bi-dimensional modelling of the BCG surface brightness profile reveals the presence of a…
On the possibilities of classical nova identifications among historical Far Eastern guest star observations
Hoffmann, Susanne M.; Vogt, Nikolaus; Tappert, Claus
More than 100 guest star observations have been obtained by Chinese, Korean, Japanese, and Vietnamese astronomers between ∼600 BCE and ∼1690 CE. Comparing the coordinates from the information given in old texts for eight supernova recoveries with modern supernova remnant positions, we estimate the typical positional accuracy of the order of 0.3–7°…
Islands of ice on Mars and Pluto
Bapst, Jonathan; Byrne, Shane; Becerra, Patricio +1 more
Ice sheets, such as the polar layered deposits (PLDs) of Mars, are of great interest as records of past climate. Smaller outlier ice deposits near the north and south PLDs are likely more sensitive to climate changes and thus may hold information about more recent climate history. However, the southern outlier deposits have largely remained unmapp…