Search Publications

Multipoint study of the energy release and transport in the 28 March 2022, M4 flare using STIX, EUI, and AIA during the first Solar Orbiter nominal mission perihelion
DOI: 10.1051/0004-6361/202346354 Bibcode: 2023A&A...679A..99P

Krucker, Säm; Veronig, Astrid M.; Dissauer, Karin +8 more

Context. The Spectrometer Telescope for Imaging X-rays (STIX) on board Solar Orbiter enables exciting multipoint studies of energy release and transport in solar flares by observing the Sun from many different distances and vantage points out of the Sun-Earth line.
Aims: We present a case study of an M4-class flare that occurred on 28 March 2…

2023 Astronomy and Astrophysics
SolarOrbiter 7
A Catalog of Distance Determinations for the LAMOST DR8 K Giants in the Galactic Halo
DOI: 10.3847/1538-3881/acc9bb Bibcode: 2023AJ....165..224Z

Zhao, Gang; Rix, Hans-Walter; Yang, Chengqun +4 more

We present a catalog of distances for 19,544 K giants drawn from Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) DR8. Most of them are located in the halo of the Milky Way up to ~120 kpc. There are 15% K giants without Sloan Digital Sky Survey (SDSS) photometry, for which we supplements with Pan-STARRS1 (PS1) photometry calibrat…

2023 The Astronomical Journal
Gaia 7
The VISCACHA survey. VIII. Chemical evolution history of the Small Magellanic Cloud west halo clusters
DOI: 10.1051/0004-6361/202346648 Bibcode: 2023A&A...677A..35S

Minniti, D.; Bica, E.; Maia, F. +12 more

The chemical evolution history of the Small Magellanic Cloud (SMC) has been a matter of debate for decades. The challenges in understanding the SMC chemical evolution are related to a very slow star formation rate (SFR) combined with bursts triggered by the multiple interactions between the SMC and the Large Magellanic Cloud, a significant (∼0.5 d…

2023 Astronomy and Astrophysics
Gaia 7
Disintegration of Long-period Comet C/2021 A1 (Leonard)
DOI: 10.3847/1538-3881/acb53b Bibcode: 2023AJ....165..122J

Mutchler, Max; Jewitt, David; Agarwal, Jessica +3 more

We present imaging observations of the disintegrating long-period comet C/2021 A1 (Leonard). High-resolution observations with the Hubble Space Telescope show no evidence for surviving fragments, and place a 3σ upper limit on their possible radius of ~60 m (albedo 0.1 assumed). In contrast, wide-field observations from the Swan Hill Observatory, A…

2023 The Astronomical Journal
eHST 7
The structural properties of multiple populations in the dynamically young globular cluster NGC 2419
DOI: 10.1051/0004-6361/202346792 Bibcode: 2023A&A...677A...8O

Vesperini, Enrico; Cadelano, Mario; Dalessandro, Emanuele +3 more

NGC 2419 is likely the globular cluster (GC) with the lowest dynamical age in the Galaxy. This makes it an extremely interesting target for studying the properties of its multiple populations (MPs), as they are likely to have been affected only modestly by long-term dynamical evolution effects. Here we present for the first time a detailed analysi…

2023 Astronomy and Astrophysics
Gaia eHST 7
Searching for the warm-hot intergalactic medium using XMM-Newton high-resolution X-ray spectra
DOI: 10.1093/mnras/stad698 Bibcode: 2023MNRAS.521.3098G

Churazov, E.; Kallman, T. R.; García, Javier A. +1 more

The problem of missing baryons in the local universe remains an open question. One proposed alternative is that at low redshifts missing baryons are in the form of the warm-hot intergalactic medium (WHIM). In order to test this idea, we present a detailed analysis of X-ray high-resolution spectra of six extragalactic sources, Mrk 421, 1ES 1028+511…

2023 Monthly Notices of the Royal Astronomical Society
XMM-Newton 7
In-flight validation of the Metis visible-light polarimeter coronagraph on board Solar Orbiter
DOI: 10.1051/0004-6361/202244069 Bibcode: 2023A&A...672A..14L

Sasso, C.; Romoli, M.; Andretta, V. +21 more

Context. The Metis coronagraph is one of the remote sensing instruments of the ESA-NASA Solar Orbiter mission. The goal for the instrument is to enable the study of the solar atmosphere and solar wind by simultaneously acquiring images of the solar corona at two different wavelengths: visible light (VL), within a band ranging from 580 nm to 640 nm…

2023 Astronomy and Astrophysics
SOHO SolarOrbiter 7
Constraining the assembly time of the stellar haloes of nearby Milky Way-mass galaxies through AGB populations
DOI: 10.1093/mnras/stad2480 Bibcode: 2023MNRAS.525.4497H

Bell, Eric F.; Holwerda, Benne W.; Monachesi, Antonela +5 more

The star formation histories (SFHs) of galactic stellar haloes offer crucial insights into the merger history of the galaxy and the effects of those mergers on their hosts. Such measurements have revealed that while the Milky Way's most important merger was 8-10 Gyr ago, M31's largest merger was more recent, within the last few Gyr. Unfortunately,…

2023 Monthly Notices of the Royal Astronomical Society
eHST 7
Catching a nova X-ray/UV flash in the visible? Early spectroscopy of the very slow Nova Velorum 2022 (Gaia22alz)
DOI: 10.1093/mnras/stad1914 Bibcode: 2023MNRAS.524.1946A

Mukai, K.; Sokoloski, J. L.; Mróz, P. +22 more

We present early spectral observations of the very slow Galactic nova Gaia22alz, over its gradual rise to peak brightness that lasted 180 d. During the first 50 d, when the nova was only 3-4 mag above its normal brightness, the spectra showed narrow (FWHM ≈ 400 km s-1) emission lines of H Balmer, He I, He II, and C IV but no P Cygni abs…

2023 Monthly Notices of the Royal Astronomical Society
Gaia 7
Revisiting Orbital Evolution in HAT-P-2 b and Confirmation of HAT-P-2 c
DOI: 10.3847/1538-3881/acedf1 Bibcode: 2023AJ....166..136D

Fulton, Benjamin J.; Howard, Andrew W.; Winn, Joshua N. +5 more

One possible formation mechanism for Hot Jupiters is that high-eccentricity gas giants experience tidal interactions with their host star that cause them to lose orbital energy and migrate inwards. We study these types of tidal interactions in an eccentric Hot Jupiter called HAT-P-2 b, which is a system where a long-period companion has been sugge…

2023 The Astronomical Journal
Gaia Hipparcos 7