Search Publications
The nuclear environment of the NLS1 Mrk 335: Obscuration of the X-ray line emission by a variable outflow
Harrison, F. A.; Schartel, N.; Santos-Lleó, M. +12 more
We present XMM-Newton, NuSTAR, Swift, and Hubble Space Telescope observations of the Narrow-line Seyfert 1 galaxy Mrk 335 in a protracted low state in 2018 and 2019. The X-ray flux is at the lowest level so far observed, and the extremely low continuum flux reveals a host of soft X-ray emission lines from photoionized gas. The simultaneous UV flux…
The structure of the Mg II broad line emitting region in Type 1 AGNs
Popović, Luka Č.; Kovačević-Dojčinović, Jelena; Marčeta-Mandić, Sladjana
We investigate the structure of the Mg II broad line emission region in a sample of 284 Type 1 active galactic nuclei (AGNs), through comparing the kinematical parameters of the broad Mg II and broad Hβ lines. We found that the Mg II emitting region has more complex kinematics than the Hβ one. It seems that the Mg II broad line originates from two…
Benchmark ages for the Gaia benchmark stars
Feltzing, Sofia; Lindegren, Lennart; Sahlholdt, Christian L. +1 more
In the era of large-scale surveys of stars in the Milky Way, stellar ages are crucial for studying the evolution of the Galaxy. But determining ages of field stars is notoriously difficult; therefore, we attempt to determine benchmark ages for the extensively studied Gaia benchmark stars which can be used for validation purposes. By searching the …
A statistically significant lack of debris discs in medium separation binary systems
Wyatt, Mark C.; Kennedy, Grant M.; Su, Kate Y. L. +1 more
We compile a sample of 341 binary and multiple star systems with the aim of searching for and characterizing Kuiper belt-like debris discs. The sample is assembled by combining several smaller samples studied in previously published work with targets from two unpublished Herschel surveys. We find that 38 systems show excess emission at 70 or 100 &…
Random Forest identification of the thin disc, thick disc, and halo Gaia-DR2 white dwarf population
Solano, E.; Rebassa-Mansergas, A.; Torres, S. +3 more
Gaia-DR2 has provided an unprecedented number of white dwarf candidates of our Galaxy. In particular, it is estimated that Gaia-DR2 has observed nearly 400 000 of these objects and close to 18 000 up to 100 pc from the Sun. This large quantity of data requires a thorough analysis in order to uncover their main Galactic population properties, in pa…
OCCASO - III. Iron peak and α elements of 18 open clusters. Comparison with chemical evolution models and field stars
Jordi, C.; Casamiquela, L.; Anders, F. +10 more
The study of open-cluster chemical abundances provides insights on stellar nucleosynthesis processes and on Galactic chemo-dynamical evolution. In this paper we present an extended abundance analysis of 10 species (Fe, Ni, Cr, V, Sc, Si, Ca, Ti, Mg, O) for red giant stars in 18 OCCASO clusters. This represents a homogeneous sample regarding the in…
PAHs as tracers of the molecular gas in star-forming galaxies
Daddi, E.; Elbaz, D.; Gómez-Guijarro, C. +12 more
We combine new CO(1-0) line observations of 24 intermediate redshift galaxies (0.03 < z < 0.28) along with literature data of galaxies at 0 < z < 4 to explore scaling relations between the dust and gas content using polycyclic aromatic hydrocarbon (PAH) 6.2 µm (L6.2), CO (L^' }_CO), and infrared (LIR) lumino…
A deep view of a fossil relic in the Galactic bulge: the Globular Cluster HP 1
Bica, E.; Nardiello, D.; Barbuy, B. +7 more
HP 1 is an α-enhanced and moderately metal-poor bulge globular cluster with a blue horizontal branch. These combined characteristics make it a probable relic of the early star formation in the innermost Galactic regions. Here, we present a detailed analysis of a deep near-infrared (NIR) photometry of HP 1 obtained with the NIR GSAOI + GeMS camera …
Jets blowing bubbles in the young radio galaxy 4C 31.04
Groves, Brent; Mukherjee, Dipanjan; Wagner, Alexander Y. +5 more
We report the discovery of shocked molecular and ionized gas resulting from jet-driven feedback in the low-redshift (z = 0.0602) compact radio galaxy 4C 31.04 using near-IR imaging spectroscopy. 4C 31.04 is a ∼100 pc double-lobed Compact Steep Spectrum source believed to be a very young active galactic nucleus (AGN). It is hosted by a giant ellipt…
Probing the final-stage progenitor evolution for Type IIP Supernova 2017eaw in NGC 6946
Wang, Lifan; Wang, Xiaofeng; Zhang, Jujia +6 more
We presented a detailed analysis of progenitor properties of type IIP supernova 2017eaw in NGC 6946, based on the pre-explosion images and early-time observations obtained immediately after the explosion. An unusually red star, with MF814W = -6.9 mag and mF606W - mF814W = 2.9 ± 0.2 mag, can be identified at the SN …