Search Publications

High resolution X-ray spectroscopy of V4641 Sgr during its 2020 outburst
DOI: 10.1093/mnras/stac2213 Bibcode: 2022MNRAS.516..124S

Heinke, C. O.; Miller, J. M.; Gandhi, P. +7 more

We observed the Galactic black hole X-ray binary V4641 Sgr with the high resolution transmission gratings on Chandra during the source's 2020 outburst. Over two epochs of Chandra gratings observations, we see numerous highly ionized metal lines, superimposed on a hot, disc-dominated X-ray continuum. The measured inner disc temperatures and luminos…

2022 Monthly Notices of the Royal Astronomical Society
Gaia 9
SHARP - VIII. J0924+0219 lens mass distribution and time-delay prediction through adaptive-optics imaging
DOI: 10.1093/mnras/stac1081 Bibcode: 2022MNRAS.513.2349C

Treu, Tommaso; Lagattuta, David J.; Fassnacht, Christopher D. +6 more

Strongly lensed quasars can provide measurements of the Hubble constant (H0) independent of any other methods. One of the key ingredients is exquisite high-resolution imaging data, such as Hubble Space Telescope (HST) imaging and adaptive-optics (AO) imaging from ground-based telescopes, which provide strong constraints on the mass dist…

2022 Monthly Notices of the Royal Astronomical Society
eHST 9
The Internal Proper Motion Kinematics of NGC 346: Past Formation and Future Evolution
DOI: 10.3847/1538-4357/ac8005 Bibcode: 2022ApJ...936..135S

Anderson, J.; Lennon, D. J.; Sabbi, E. +6 more

We investigate the internal kinematics of the young star-forming region NGC 346 in the Small Magellanic Cloud (SMC). We used two epochs of deep F555W and F814W Hubble Space Telescope Advanced Camera for Surveys observations with an 11 yr baseline to determine proper motions and study the kinematics of different populations, as identified by their …

2022 The Astrophysical Journal
Gaia eHST 9
A Mid-infrared Study of Directly Imaged Planetary-mass Companions Using Archival Spitzer/IRAC Images
DOI: 10.3847/1538-3881/ac3745 Bibcode: 2022AJ....163...36M

Kraus, Adam L.; Martinez, Raquel A.

The atmospheres and accretion disks of planetary-mass and substellar companions provide an unprecedented look into planet and moon formation processes, most notably the frequency and lifetime of circumplanetary disks. In our ongoing effort to leverage the extraordinary sensitivity of the Spitzer/Infrared Array Camera (IRAC) at 3.6, 4.5, 5.8, and 8…

2022 The Astronomical Journal
Gaia eHST 9
V392 Persei: A γ-ray bright nova eruption from a known dwarf nova
DOI: 10.1093/mnras/stac1577 Bibcode: 2022MNRAS.514.6183M

Boyd, D.; Starrfield, S.; Page, K. L. +57 more

V392 Persei is a known dwarf nova (DN) that underwent a classical nova eruption in 2018. Here we report ground-based optical, Swift UV and X-ray, and Fermi-LAT γ-ray observations following the eruption for almost three years. V392 Per is one of the fastest evolving novae yet observed, with a t2 decline time of 2 d. Early spectra present…

2022 Monthly Notices of the Royal Astronomical Society
Gaia 9
The VMC survey. XLV. Proper motion of the outer LMC and the impact of the SMC
DOI: 10.1051/0004-6361/202142148 Bibcode: 2022A&A...663A.107S

de Grijs, Richard; Ripepi, Vincenzo; Cioni, Maria-Rosa L. +8 more

Context. The Large Magellanic Cloud (LMC) is the most luminous satellite galaxy of the Milky Way and, owing to its companion, the Small Magellanic Cloud (SMC), represents an excellent laboratory to study the interaction of dwarf galaxies.
Aims: The aim of this study is to investigate the kinematics of the outer regions of the LMC by using ste…

2022 Astronomy and Astrophysics
Gaia 9
New Constraints on Cosmic Particle Populations at the Galactic Center Using X-Ray Observations of the Molecular Cloud Sagittarius B2
DOI: 10.3847/1538-4357/ac7717 Bibcode: 2022ApJ...934...19R

Zhang, Shuo; Clavel, Maïca; Perez, Kerstin +2 more

The Sagittarius B2 (Sgr B2) molecular cloud complex is an X-ray reflection nebula whose nonthermal X-ray emissions have continued to decrease since 2001 as it reprocesses one or more past energetic outbursts from the supermassive black hole Sagittarius A* at the Galactic Center. The X-ray reflection model explains the observed time variability of …

2022 The Astrophysical Journal
Herschel XMM-Newton 9
Acceleration and Expansion of a Coronal Mass Ejection in the High Corona: Role of Magnetic Reconnection
DOI: 10.3847/1538-4357/ac75d4 Bibcode: 2022ApJ...933..169Z

Temmer, Manuela; Lugaz, Noé; Zhuang, Bin +2 more

The important role played by magnetic reconnection in the early acceleration of coronal mass ejections (CMEs) has been widely discussed. However, as CMEs may have expansion speeds comparable to their propagation speeds in the corona, it is not clear whether and how reconnection contributes to the true acceleration and expansion separately. To addr…

2022 The Astrophysical Journal
SOHO 9
On the Magnetosphere-Ionosphere Coupling During the May 2021 Geomagnetic Storm
DOI: 10.1029/2021SW003016 Bibcode: 2022SpWea..2003016P

Ubertini, P.; Battiston, R.; Plainaki, C. +20 more

On 12 May 2021 the interplanetary doppelgänger of the 9 May 2021 coronal mass ejection impacted the Earth's magnetosphere, giving rise to a strong geomagnetic storm. This paper discusses the evolution of the various events linking the solar activity to the Earth's ionosphere with special focus on the effects observed in the circumterrestrial envir…

2022 Space Weather
SOHO 9
VLT spectropolarimetry of comet 67P: dust environment around the end of its intense southern summer
DOI: 10.1051/0004-6361/202141865 Bibcode: 2022A&A...657A..40K

Kolokolova, Ludmilla; Agarwal, Jessica; Snodgrass, Colin +5 more

Context. A cornucopia of Rosetta and ground-based observational data sheds light on the evolution of the characteristics of dust particles from comet 67P/Churyumov-Gerasimenko (hereafter 67P) with seasons, implying the different dust environments in the source regions on the surface of the comet.
Aims: We aim to constrain the properties of th…

2022 Astronomy and Astrophysics
Rosetta 9