Search Publications

Recurrence of galactic cosmic-ray intensity and anisotropy in solar minima 23/24 and 24/25 observed by ACE/CRIS, STEREO, SOHO/EPHIN and neutron monitors. Fourier and wavelet analysis
DOI: 10.1051/0004-6361/202039651 Bibcode: 2021A&A...646A.128M

Modzelewska, R.; Gil, A.


Aims: We studied the 27-day variations of galactic cosmic rays (GCRs) based on neutron monitor (NM), ACE/CRIS, STEREO, and SOHO/EPHIN measurements in the solar minima 23/24 and 24/25, which are characterized by the opposite polarities of solar magnetic cycle. We used the opportunity to reanalyze the polarity dependence of the amplitudes of th…

2021 Astronomy and Astrophysics
SOHO 15
Radiative Driving of the AGN Outflows in the Narrow-line Seyfert 1 Galaxy NGC 4051
DOI: 10.3847/1538-4357/ac0246 Bibcode: 2021ApJ...916...31M

Fischer, Travis C.; Crenshaw, D. Michael; Schmitt, Henrique R. +5 more

We explore the properties of ionized gas in the nuclear and circumnuclear environment of the narrow-line Seyfert 1 galaxy NGC 4051 using spectroscopic and imaging observations from the Hubble Space Telescope (HST) and Apache Point Observatory's ARC 3.5 m Telescope. We identify an unresolved moderate-density intermediate-width component and a high-…

2021 The Astrophysical Journal
eHST 15
Nebular Hα emission in Type Ia supernova 2016jae
DOI: 10.1051/0004-6361/202141218 Bibcode: 2021A&A...652A.115E

Cappellaro, E.; Benetti, S.; Morrell, N. +7 more

There is a wide consensus that Type Ia supernovae (SNe Ia) originate from the thermonuclear explosion of CO white dwarfs (WDs), with the lack of hydrogen in the observed spectra as a distinctive feature. Here, we present supernova (SN) 2016jae, which was classified as an SN Ia from a spectrum obtained soon after its discovery. The SN reached a B-b…

2021 Astronomy and Astrophysics
Gaia 15
Dielectric Properties of the Medusae Fossae Formation and Implications for Ice Content
DOI: 10.1029/2020JE006601 Bibcode: 2021JGRE..12606601C

Campbell, Bruce A.; Morgan, Gareth A.; Watters, Thomas R.

The extensive Medusae Fossae Formation (MFF) along the dichotomy boundary on Mars has geologic features indicative of wind erosion of low density material. There is evidence suggesting a water ice component, but with considerable uncertainty linked to the unknown MFF porosity and compaction behavior. We use SHARAD radar sounder data to estimate th…

2021 Journal of Geophysical Research (Planets)
MEx 15
Tidally perturbed oblique pulsations in the hierarchical triple system V1031 Orionis
DOI: 10.1093/pasj/psab044 Bibcode: 2021PASJ...73..809L

Lee, Jae Woo

We present Transiting Exoplanet Survey Satellite (TESS) photometry of the triple star system V1031 Ori (AB)C, which exhibits short-period oscillations superimposed on an eclipsing light curve.The high-quality data were analyzed in detail and combined with the published spectroscopic measurements to obtain the fundamental stellar parameters of the …

2021 Publications of the Astronomical Society of Japan
Gaia 15
Constraining stellar rotation and planetary atmospheric evolution of a dozen systems hosting sub-Neptunes and super-Earths
DOI: 10.1051/0004-6361/202142010 Bibcode: 2021A&A...656A.157B

Fossati, L.; Kubyshkina, D.; Bonfanti, A. +1 more

Context. Planetary atmospheric evolution modelling is a prime tool for understanding the observed exoplanet population and constraining formation and migration mechanisms, but it can also be used to study the evolution of the activity level of planet hosts.
Aims: We constrain the planetary atmospheric mass fraction at the time of the dispersa…

2021 Astronomy and Astrophysics
CHEOPS 15
The rare X-ray flaring activity of the ultraluminous X-ray source NGC 4559 X7
DOI: 10.1093/mnras/stab913 Bibcode: 2021MNRAS.504..551P

Salvaterra, R.; Wolter, A.; Pintore, Fabio +9 more

Ultraluminous X-ray sources are considered amongst the most extremely accreting objects in the local Universe. The recent discoveries of pulsating neutron stars in ULXs strengthened the scenario of highly super-Eddington accretion mechanisms on stellar mass compact objects. In this work, we present the first long-term light curve of the source NGC…

2021 Monthly Notices of the Royal Astronomical Society
XMM-Newton 15
Ultracool dwarfs in deep extragalactic surveys using the virtual observatory: ALHAMBRA and COSMOS
DOI: 10.1093/mnras/staa3423 Bibcode: 2021MNRAS.501..281S

Béjar, V. J. S.; Martín, E. L.; Huélamo, N. +8 more

Ultracool dwarfs (UCDs) encompass a wide variety of compact stellar-like objects with spectra classified as late-M, L, T, and Y. Most of them have been discovered using wide-field imaging surveys. The Virtual Observatory (VO) has proven to be of great utility to efficiently exploit these astronomical resources. We aim to validate a VO methodology …

2021 Monthly Notices of the Royal Astronomical Society
Gaia 15
Mysterious, variable, and extremely hot: White dwarfs showing ultra-high excitation lines. I. Photometric variability
DOI: 10.1051/0004-6361/202140289 Bibcode: 2021A&A...647A.184R

Pelisoli, Ingrid; Reindl, Nicole; Schaffenroth, Veronika +3 more

Context. About 10% of all stars exhibit absorption lines of ultra-highly excited (UHE) metals (e.g., O VIII) in their optical spectra when entering the white dwarf cooling sequence. This is something that has never been observed in any other astrophysical object, and poses a decades-long mystery in our understanding of the late stages of stellar e…

2021 Astronomy and Astrophysics
Gaia eHST 15
Contemporaneous Multiwavelength and Precovery Observations of the Active Centaur P/2019 LD2 (ATLAS)
DOI: 10.3847/PSJ/abe23d Bibcode: 2021PSJ.....2...48K

Woodney, Laura M.; Volk, Kathryn; Kareta, Theodore +10 more

The Gateway Centaur and Jupiter co-orbital P/2019 LD2 (ATLAS) provides the first opportunity to observe the migration of a solar system small body from a Centaur orbit to a Jupiter Family Comet (JFC) four decades from now. The Gateway transition region is beyond where water ice can power cometary activity, and coma production there is as poorly un…

2021 The Planetary Science Journal
Gaia 15