Search Publications

The Gaia spectrophotometric standard stars survey - V. Preliminary flux tables for the calibration of Gaia DR2 and (E)DR3
DOI: 10.1093/mnras/stab766 Bibcode: 2021MNRAS.503.3660P

Harrison, D. L.; Jordi, C.; Rainer, M. +15 more

We present the flux tables of the spectrophotometric standard stars (SPSS) used to calibrate in flux the Gaia DR2 and (E)DR3 data releases. The latest SPSS grid version contains 112 stars, whose flux tables agree to better than 1 per cent with the CALSPEC spectra of 11 flux standards for the calibration of the Hubble Space Telescope. The synthetic…

2021 Monthly Notices of the Royal Astronomical Society
Gaia 18
On the Contribution of the X-Ray Source to the Extended Nebular He II Emission in IZW18
DOI: 10.3847/2041-8213/abe41b Bibcode: 2021ApJ...908L..54K

Guerrero, M. A.; Ramos-Larios, G.; Kehrig, C. +1 more

Nebular He II emission implies the presence of energetic photons (E ≥ 54 eV). Despite the great deal of effort dedicated to understanding He II ionization, its origin has remained mysterious, particularly in metal-deficient star-forming (SF) galaxies. Unfolding He II-emitting, metal-poor starbursts at z ∼ 0 can yield insight into the powerful ioni…

2021 The Astrophysical Journal
XMM-Newton 18
Outflows, envelopes, and disks as evolutionary indicators in Lupus young stellar objects
DOI: 10.1051/0004-6361/202039228 Bibcode: 2021A&A...648A..41V

de Gregorio-Monsalvo, I.; Lopez, C.; Fernández-López, M. +4 more

Context. The Lupus star-forming complex includes some of the closest low-mass star-forming regions, and together they house objects that span evolutionary stages from prestellar to premain sequence.
Aims: By studying seven objects in the Lupus clouds from prestellar to protostellar stages, we aim to test if a coherence exists between commonly…

2021 Astronomy and Astrophysics
AKARI 18
Evidence Suggesting That 'Oumuamua Is the 30 Myr Old Product of a Molecular Cloud
DOI: 10.3847/1538-4357/ac0729 Bibcode: 2021ApJ...917...20H

Hsieh, Cheng-Han; Laughlin, Gregory; Arce, Héctor G.

The appearance of interstellar objects (ISOs) in the solar system-and specifically the arrival of 1I/'Oumuamua-points to a significant number density of free-floating bodies in the solar neighborhood. We review the details of 'Oumuamua's pre-encounter Galactic orbit, which intersected the solar system at very nearly its maximum vertical and radial…

2021 The Astrophysical Journal
Gaia 18
Evidence of the multi-thermal nature of spicular downflows. Impact on solar atmospheric heating
DOI: 10.1051/0004-6361/202141404 Bibcode: 2021A&A...654A..51B

Joshi, Jayant; Martínez-Sykora, Juan; De Pontieu, Bart +4 more

Context. Spectroscopic observations of the emission lines formed in the solar transition region commonly show persistent downflows on the order of 10−15 km s−1. The cause of such downflows, however, is still not fully clear and has remained a matter of debate.
Aims: We aim to understand the cause of such downflows by studying the c…

2021 Astronomy and Astrophysics
IRIS 18
INTEGRAL Limits on Past High-energy Activity from FRB 20200120E in M81
DOI: 10.3847/2041-8213/ac2ee7 Bibcode: 2021ApJ...921L...3M

Götz, D.; Mereghetti, S.; Rigoselli, M. +1 more

The repeating fast radio burst FRB 20200120E is located in a globular cluster belonging to the nearby M81 galaxy. Its small distance (3.6 Mpc) and accurate localization make it an interesting target to search for bursting activity at high energies. From 2003 November to 2021 September, the INTEGRAL satellite has obtained an exposure time of 18 Ms …

2021 The Astrophysical Journal
INTEGRAL 18
Measuring chemical abundances with infrared nebular lines: HII-CHI-MISTRY-IR
DOI: 10.1051/0004-6361/202039716 Bibcode: 2021A&A...652A..23F

Spinoglio, L.; Amorín, R.; Pérez-Montero, E. +2 more

We provide a new method for deriving heavy element abundances taking advantage of the unique suite of fine-structure lines in the mid- to far-infrared (IR) range. Using grids of photo-ionisation models that cover a wide range in O/H and N/O abundances and ionisation parameter, our code HII-CHI-MISTRY-IR (HCM-IR) provides model-based abundances bas…

2021 Astronomy and Astrophysics
Herschel 18
Hunting for intermediate-mass black holes in globular clusters: an astrometric study of NGC 6441
DOI: 10.1093/mnras/stab474 Bibcode: 2021MNRAS.503.1490H

van der Marel, Roeland P.; Neumayer, Nadine; Watkins, Laura L. +6 more

We present an astrometric study of the proper motions (PMs) in the core of the globular cluster NGC 6441. The core of this cluster has a high density and observations with current instrumentation are very challenging. We combine ground-based, high-angular-resolution NACO@VLT images with Hubble Space Telescope ACS/HRC data and measure PMs with a te…

2021 Monthly Notices of the Royal Astronomical Society
Gaia eHST 18
Future Prospects for Solar EUV and Soft X-ray Solar Spectroscopy Missions
DOI: 10.3389/fspas.2021.662790 Bibcode: 2021FrASS...8...50Y

Young, Peter R.

Future prospects for solar spectroscopy missions operating in the extreme ultraviolet (EUV) and soft X-ray (SXR) wavelength ranges, 1.2--1600~\AA, are discussed. NASA is the major funder of Solar Physics missions, and brief summaries of the opportunities for mission development under NASA are given. Upcoming major solar missions from other nations…

2021 Frontiers in Astronomy and Space Sciences
SolarOrbiter 18
The AMBRE Project: Origin and evolution of sulfur in the Milky Way
DOI: 10.1051/0004-6361/202040147 Bibcode: 2021A&A...647A.162P

Recio-Blanco, A.; de Laverny, P.; Álvarez, M. A. +4 more

Context. Sulfur is a volatile chemical element that plays an important role in tracing the chemical evolution of the Milky Way and external galaxies. However, its nucleosynthesis origin and abundance variations in the Galaxy are still unclear because the number of available stellar sulfur abundance measurements is currently rather small.
Aims…

2021 Astronomy and Astrophysics
Gaia 18