47 citations · 145 across the 18 of their papers we have counts for
18 papers
Dimming and pulsation shock of the coalesced star V838 Monocerotis
T. Kamiński, C. E. Woodward, T. Liimets +3
V838 Mon is the remnant of a stellar merger that occurred in 2002. Twenty-four years after the merger, the remnant closely resembles a red supergiant, but its luminosity is sustain…
KDP as a thermal blocking filter -- Deep near IR observations with a warm narrow band filter
J. K. M. Viuho, A. A. Djupvik, A. N. Sørensen +5
Ground-based astronomy suffers from strong atmospheric line- and thermal continuum emission, at the near infrared (NIR, 0.7-1.1m), and short-wave infrared (SWIR, 1.1-2.5m) wa…
The Diamond Ring in Cygnus X: Advanced stage of an expanding bubble of ionised carbon
Simon M. Dannhauer, Sebastian Vider, Nicola Schneider +18
The "Diamond Ring" in Cygnus X, southwest of the DR21 ridge, is a nearly circular structure of 6 pc in diameter, prominent in FIR emission and enclosed by clumpy molecular cl…
Advancing accuracy in age determinations of old-disk stars using an oscillating red giant in an eclipsing binary
J. S. Thomsen, A. Miglio, K. Brogaard +26
The study of resonant oscillation modes in low-mass red giant branch stars enables their ages to be inferred with exceptional (10%) precision, unlocking the possibility to re…
Observations of UX Ori in deep minima with the Nordic Optical Telescope. I. Analysis of spectral lines
L. V. Tambovtseva, A. A. Djupvik, V. P. Grinin +11
UX Orionis stars are the most active young stars; they undergo sporadic fadings of 2 - 4 magnitudes in the V-band, due to variable circumstellar extinction caused by a nearly edge-…
Detection of binary companions below the diffraction limit with lucky imaging
Miguel A. Cagigas, R. Clavero, Manuel P. Cagigal +10
We provide a technique for resolving intermediate-separation binaries stars with medium-sized telescopes (i.e. diameter less than or equal to 2.5 m) at wavelengths around 825 nm in…
A 500 pc volume-limited sample of hot subluminous stars I. Space density, scale height, and population properties
H. Dawson, S. Geier, U. Heber +25
We present the first volume-limited sample of spectroscopically confirmed hot subluminous stars out to 500 pc, defined using the accurate parallax measurements from the {\em Gaia}…
Modelling UX Ori Star Eclipses based on Spectral Observations with the Nordic Optical Telescope. I. RR Tau
V. P. Grinin, L. V. Tambovtseva, A. A. Djupvik +12
Based on observations obtained with the Nordic Optical Telescope we investigate the spectral variability of the Herbig Ae star RR Tau. This star belongs to the UX Ori family, chara…
Density streams in the disc winds of Classical T Tauri stars
P. P. Petrov, K. N. Grankin, E. V. Babina +5
Spectral and photometric variability of the Classical T Tauri stars RY Tau and SU Aur from 2013 to 2022 is analyzed. We find that in SU Aur the H-alpha line's flux at radial veloci…
V838 Mon: A slow waking up of Sleeping Beauty?
T. Liimets, I. Kolka, M. Kraus +15
Context. V838 Monocerotis is a peculiar binary that underwent an immense stellar explosion in 2002, leaving behind an expanding cool supergiant and a hot B3V companion. Five years…
Expanding shells around young clusters -- S 171/Be 59
G. F. Gahm, M. J. C. Wilhelm, C. M. Persson +2
Some HII regions that surround young stellar clusters are bordered by molecular shells that appear to expand at a rate inconsistent with our current model simulations. In this stud…
Star formation in two irradiated globules around Cygnus OB2
F. Comerón, N. Schneider, A. A. Djupvik
We investigate the young stellar populations associated with DR 18 and ECX 6-21, which are two isolated globules irradiated by the O-type stars of the Cygnus OB2 association. Both…
The extended population associated with W40
F. Comerón, A. A. Djupvik, N. Schneider
W40 is a heavily obscured bipolar HII region projected in the direction of the Aquila Rift and ionized by hot stars in a central, partly embedded cluster. The study of the cluster…
The Infrared Evolution of Dust in V838 Monocerotis
C. E. Woodward, A. Evans, D. P. K. Banerjee +7
Luminous Red Variables (LRVs) are most likely eruptions that are the outcome of stellar mergers. V838 Mon is one of the best-studied members of this class, representing an archetyp…
SRG/ART-XC discovery of SRGA J204318.2+443815: towards the complete population of faint X-ray pulsars
A. A. Lutovinov, S. S. Tsygankov, I. A. Mereminskiy +19
We report a discovery of a new long-period X-ray pulsar SRGA J204318.2+443815/SRGe J204319.0+443820 in the Be binary system. The source was found in the second all-sky survey by th…
K2-31b, a grazing transiting hot Jupiter on an 1.26-day orbit around a bright G7V star
S. Grziwa, D. Gandolfi, Sz. Csizmadia +25
We report the discovery of K2-31b, the first confirmed transiting hot Jupiter detected by the K2 space mission. We combined K2 photometry with FastCam lucky imaging and FIES and HA…
Kepler-77b: a very low albedo, Saturn-mass transiting planet around a metal-rich solar-like star
D. Gandolfi, H. Parviainen, M. Fridlund +18
We report the discovery of Kepler-77b (alias KOI-127.01), a Saturn-mass transiting planet in a 3.6-day orbit around a metal-rich solar-like star. We combined the publicly available…
The Crab pulsar and its pulsar-wind nebula in the optical and infrared
A. Tziamtzis, P. Lundqvist, A. A. Djupvik
We investigate the emission mechanism and evolution of pulsars that are associated with supernova remnants. We used imaging techniques in both the optical and near infrared, using…