Search Publications
Theoretical Light-curve Models of the Symbiotic Nova CN Cha-Optical Flat Peak for 3 Yr
Kato, Mariko; Hachisu, Izumi
CN Cha is a slow symbiotic nova characterized by a 3 yr long optical flat peak followed by a rapid decline. We present theoretical light curves for CN Cha, based on hydrostatic approximation, and estimate the white-dwarf (WD) mass to be ~0.6 M ⊙ for a low metal abundance of Z = 0.004. These kinds of flat-peak novae are border objects be…
Photometric follow-up of the 20 Myr old multi-planet host star V1298 Tau with CHEOPS and ground-based telescopes
Béjar, V. J. S.; Zapatero Osorio, M. R.; Scandariato, G. +25 more
Context. The 20 Myr old star V1298 Tau hosts at least four planets. Since its discovery, this system has been a target of intensive photometric and spectroscopic monitoring. To date, the characterisation of its architecture and planets' fundamental properties has been very challenging.
Aims: The determination of the orbital ephemeris of the o…
Calibrating the effective magnitudes of type Ia supernovae with a model-independent method
Li, Zhongmu; Chen, Jing; Hu, Jian +2 more
This research explores the correlation between the absolute magnitude and the redshift of type Ia supernovae (SNe Ia) with a model-independent approach. The Pantheon sample of SNe Ia and strong gravitational lensing systems (SGLS) are used. With the cosmic distance-duality relation (CDDR), the evolution parameter of the magnitude, the light curve …
Extreme Red-wing Enhancements of UV Lines during the 2022 March 30 X1.3 Solar Flare
Polito, Vanessa; Xu, Yan; Jing, Ju +3 more
Here, we present the study of a compact emission source during an X1.3 flare on 2022 March 30. Within a ~41 s period (17:34:48 UT to 17:35:29 UT), Interface Region Imaging Spectrograph observations show spectral lines of Mg II, C II, and Si IV with extremely broadened, asymmetric red wings. This source of interest (SOI) is compact, ~1.″6, and is l…
Dark dust. III. The high-quality single-cloud reddening curve sample: Scrutinizing extinction curves in the Milky Way
Krełowski, J.; Siebenmorgen, R.; Chini, Rolf +2 more
The nature of dust in the diffuse interstellar medium can be best investigated by means of reddening curves where only a single interstellar cloud lies between the observer and the background source. Published reddening curves often suffer from various systematic uncertainties. We merged a sample of 820 reddening curves of stars for which both FOR…
Applied Machine-Learning Models to Identify Spectral Sub-Types of M Dwarfs from Photometric Surveys
Sithajan, Sirinrat; Meethong, Sukanya
M dwarfs are the most abundant stars in the Solar Neighborhood and they are prime targets for searching for rocky planets in habitable zones. Consequently, a detailed characterization of these stars is in demand. The spectral sub-type is one of the parameters that is used for the characterization and it is traditionally derived from the observed s…
A 9 Month Hubble Space Telescope Near-UV Survey of M87. I. Light and Color Curves of 94 Novae, and a Redetermination of the Nova Rate
Graur, Or; Shara, Michael M.; Meyer, Eileen T. +10 more
M87 has been monitored with a cadence of 5 days over a span of 9 months through the near-ultraviolet (NUV; F275W) and optical (F606W) filters of the Wide Field Camera 3 (WFC3) of the Hubble Space Telescope. This unprecedented dataset yields the NUV and optical light and color curves of 94 M87 novae, characterizing the outburst and decline properti…
Global surficial water content stored in hydrated silicates at Mars from OMEGA/MEx
Poulet, François; Cardesín-Moinelo, Alejandro; Martin, Patrick +2 more
Assessing the water content at the surface of Mars is key to understand the history of water and past climate of the planet but it also is very important for future exploration and potential In Situ Resource Utilization (ISRU). Numerous locations on the surface, known to harbor hydrated minerals, have been detected and their mineralogical assembla…
Piercing the dusty veil of hyper-luminous infrared galaxies: Sub-arcsecond 144 MHz ILT observations of HLIRGs in the Lockman Hole
Bondi, M.; Prandoni, I.; Małek, K. +10 more
Context. Hyper-luminous infrared galaxies (HLIRGs) are among the most extreme systems in the Universe. With infrared (IR) luminosities of LIR > 1013 L⊙ they can have IR-derived star formation rates (SFRs) exceeding 103 M⊙ yr−1. Theoretical models have a hard time reproducing the …
On the Periodicities in Solar Rotation and Activity Determined from Sunspot-Group Data and Possible Connection with Rossby-Like Waves
Hanslmeier, Arnold; Ruždjak, Domagoj; Brajša, Roman +2 more
Analyses of solar rotation and activity, and their variations, can improve the understanding of the formation and interaction of the solar-activity bands and therefore give important observational constraints on the modelling of the solar dynamo and improve the forecast capability in solar activity and space weather. Sunspot-position data obtained…