Search Publications
Hubble Space Telescope STIS Spectroscopy of Nova T Aurigae 1891
Sion, Edward M.; Godon, Patrick; Larsen, Conor
T Aurigae is an eclipsing old nova that exploded in 1891. At a Gaia EDR3 distance of 815-871 pc, it is a relatively nearby old nova. Through ultraviolet spectral modeling and using the new precise Gaia distance, we find that the HST/STIS spectrum of T Aurigae is consistent with an accretion disk with a mass-transfer rate $\dot{M}$ of the order of …
Toward Understanding the B[e] Phenomenon. VIII. Nature and Variability of IRAS 07080+0605
Miroshnichenko, A. S.; Manset, N.; Zharikov, S. V. +13 more
We report the results of spectroscopic and photometric observations of the emission-line object IRAS 07080+0605 carried out in 2004-2021. We found that the object is significantly underluminous for its spectroscopic properties (T eff = 8500 ± 500 K, $\mathrm{log}$ g = 2.0 ± 0.5), if a strong visual attenuation by a factor of ~43 found t…
Spatially resolved mid-infrared observations of the circumstellar environment of the born-again object FG Sge
Ohnaka, K.; Jara Bravo, B. A.
Context. FG Sge has evolved from the hot central star of the young planetary nebula Hen 1-5 to a G-K supergiant in the last 100 yr. It is one of the three born-again objects that have been identified as of yet, and they are considered to have undergone a thermal pulse in the post-asymptotic giant branch evolution.
Aims: We present mid-infrare…
FG Sge: New Multicolor Photometry and Short-Term Dust Shell Clearing in 2019
Arkhipova, V. P.; Ikonnikova, N. P.; Tatarnikov, A. M. +6 more
We present the results of a new stage of the long-term photometric study of FG Sge which is a quickly evolving central star of the planetary nebula Hen 1-5. Our new observations carried out on the SAI MSU telescopes in the optical ($BVRCIC$) and infrared (IR) ($JHKLM$) regions in 2008-2021 and 2013-2021, respectively, allowed…
High-contrast imaging of HD 29992 and HD 196385 with the Gemini Planet Imager
Petrucci, R.; Jofré, E.; Gómez, M. +1 more
Based on high-contrast images obtained with the Gemini Planet Imager (GPI), we report the discovery of two point-like sources at angular separations ρ ~ 0.18 and 0.80 arcsec from the stars HD 29992 and HD 196385. A combined analysis of the new GPI observations and images from the literature indicates that the source close to HD 29992 could be a co…
ICARUS: in-situ studies of the solar corona beyond Parker Solar Probe and Solar Orbiter
Krucker, Säm; Sorriso-Valvo, Luca; Bruno, Roberto +51 more
The primary scientific goal of ICARUS (Investigation of Coronal AcceleRation and heating of solar wind Up to the Sun), a mother-daughter satellite mission, proposed in response to the ESA "Voyage 2050" Call, will be to determine how the magnetic field and plasma dynamics in the outer solar atmosphere give rise to the corona, the solar wind, and th…
Identifying interesting planetary systems for future X-ray observations
Poppenhaeger, Katja; Foster, Grace
X-ray observations of star-planet systems are important to grow our understanding of exoplanets; these observation allow for studies of photoevaporation of the exoplanetary atmosphere, and in some cases even estimations of the size of the outer planetary atmosphere. The German-Russian eROSITA instrument onboard the SRG (Spectrum Roentgen Gamma) mi…
Remote Sensing of Coronal Forces during a Solar Prominence Eruption
Thompson, B. J.; DeVore, C. R.; Uritsky, V. M.
We present a new methodology-the Keplerian Optical Dynamics Analysis (KODA)-for quantifying the dynamics of erupting magnetic structures in the solar corona. The technique involves adaptive spatiotemporal tracking of propagating intensity gradients and their characterization in terms of time-evolving Keplerian areas swept out by the position vecto…
RT Vir - A Semiregular Star With Maser Emission: Mathematical Modelling of Optical Variability
Andronov, I. L.; Kudashkina, L. S.
The historical light curve of the semiregular pulsating star RT Vir (SRb, Sp M8III) with a maser emission is analyzed based on the AAVSO database. The star is extensively studied in the IR, radio and the optical ranges. The value of the period from the CCVS (155d) conflicts with some observational data. Signs of a systematic variability were also …
Gaia-supported re-discovery of a remarkable weak line quasar from a variability and proper motion survey
Scholz, Ralf-Dieter; Meusinger, Helmut
We demonstrate that VPMS J170850.95+433223.7 is a weak line quasar (WLQ) which is remarkable in several respects. It was already classified as a probable quasar two decades ago, but with considerable uncertainty. The non-significant proper motion and parallax from the Gaia Early Data Release 3 have solidified this assumption. Based on previously u…