Search Publications

Outlier Detection in the DESI Bright Galaxy Survey
DOI: 10.3847/2041-8213/acfa03 Bibcode: 2023ApJ...956L...6L

Melchior, Peter; Ward, Charlotte; Goulding, Andy +3 more

We present an unsupervised search for outliers in the Bright Galaxy Survey (BGS) data set from the DESI Early Data Release. This analysis utilizes an autoencoder to compress galaxy spectra into a compact, redshift-invariant latent space, and a normalizing flow to identify low-probability objects. The most prominent outliers show distinctive spectr…

2023 The Astrophysical Journal
Gaia 4
Shocks and Photoionization of the Inner 650 au Jet of the Interacting Binary Star R Aquarii from Multiwavelength Hubble Space Telescope Observations
DOI: 10.3847/1538-4357/acc068 Bibcode: 2023ApJ...947...11H

Montez, Rodolfo; Raymond, John C.; Karovska, Margarita +3 more

Astrophysical jets are present in a range of environments, including young stellar objects, X-ray binaries, and active galactic nuclei, but their formation is still not fully understood. As one of the nearest symbiotic binary stars, R Aquarii (D ~ 220 pc) offers a unique opportunity to study the inner region within ~600 au of the jet source, which…

2023 The Astrophysical Journal
eHST 4
Spectroscopic survey of faint planetary-nebula nuclei - II. The subdwarf O central star of Fr 2-30
DOI: 10.1093/mnras/stad1624 Bibcode: 2023MNRAS.523.3699B

Bond, Howard E.; Zeimann, Gregory R.; Werner, Klaus +1 more

Fr 2-30 = PN? G126.8-15.5 is a faint emission nebula, hosting a 14th-mag central star that we identify here for the first time. Deep Hα and [O III] images reveal a roughly elliptical nebula with dimensions of at least 22 arcmin × 14 arcmin, fading into a surrounding network of even fainter emission. Optical spectrograms of the central star show it…

2023 Monthly Notices of the Royal Astronomical Society
Gaia 4
Studying X-ray instruments with galaxy clusters
DOI: 10.1051/0004-6361/202245099 Bibcode: 2023A&A...676A.142N

Molendi, S.; Nevalainen, J.


Aims: Our aim is to apply a scientific approach to the problem of the effective area cross-calibration of the XMM-Newton EPIC instruments. Using a sample of galaxy clusters observed with XMM-Newton EPIC, we aim to quantify the effective area cross-calibration bias between the EPIC instruments as implemented in the public calibration database …

2023 Astronomy and Astrophysics
XMM-Newton 4
A Dwarf Galaxy Debris Stream Associated with Palomar 1 and the Anticenter Stream
DOI: 10.3847/2041-8213/acbb5c Bibcode: 2023ApJ...945L...5Y

Tan, Ke-Feng; Zhao, Gang; Zhao, Jing-Kun +2 more

We report the discovery of a new stream (dubbed as Yangtze) detected in Gaia Data Release 3. The stream is at a heliocentric distance of ~9.12 kpc and spans nearly 27° by 1.°9 on the sky. The color-magnitude diagram of Yangtze indicates a stellar population of age ~11 Gyr and [M/H] ~ -0.7 dex. It has a number density of about 5.5 stars deg-2<…

2023 The Astrophysical Journal
Gaia 4
Change detection and monitoring of active Martian surface phenomena with the Colour and Stereo Surface Imaging System (CaSSIS) onboard the ExoMars Trace Gas Orbiter (TGO)
DOI: 10.1016/j.icarus.2023.115443 Bibcode: 2023Icar..39415443R

Seelos, Frank P.; Tornabene, Livio L.; Osinski, Gordon R. +10 more

Mars is host to a variety of active surface processes that relate to changes in seasonal ice/frost, slope activity, wind and processes potentially relating to liquid water. Regular monitoring and change detection of these phenomena is crucial to not only provide us insights into present day Martian surface conditions, but also its past geologic an…

2023 Icarus
ExoMars-16 4
CHEX-MATE: A non-parametric deep learning technique to deproject and deconvolve galaxy cluster X-ray temperature profiles
DOI: 10.1051/0004-6361/202347234 Bibcode: 2023A&A...679A..51I

Arnaud, M.; Pointecouteau, E.; Pratt, G. W. +21 more

Temperature profiles of the hot galaxy cluster intracluster medium (ICM) have a complex non-linear structure that traditional parametric modelling may fail to fully approximate. For this study, we made use of neural networks, for the first time, to construct a data-driven non-parametric model of ICM temperature profiles. A new deconvolution algori…

2023 Astronomy and Astrophysics
XMM-Newton 4
Optical spectroscopy of Gaia detected protostars with DOT: Can we probe protostellar photospheres?
DOI: 10.1007/s12036-023-09982-4 Bibcode: 2023JApA...44...92N

Mathew, Blesson; Manoj, P.; Narang, Mayank +7 more

Optical spectroscopy offers the most direct view of the stellar properties and the accretion indicators. Standard accretion tracers, such as Hβ, Hα and Ca II triplet lines, and most photo…

2023 Journal of Astrophysics and Astronomy
Gaia 4
Internal kinematics of dwarf satellites of MW/M31-like galaxies in TNG50
DOI: 10.1093/mnras/stad2941 Bibcode: 2023MNRAS.526.3589M

van der Marel, Roeland P.; del Pino, Andrés; Aparicio, Antonio +2 more

We present a kinematic study of a thousand of dwarf satellites of MW/M31-like hosts from the IllustrisTNG50 simulation. Internal kinematics were derived for all the snapshots to obtain a historical record of their rotation velocity in the plane of the sky (|VT|) and the amplitude of their velocity gradients along the line of sight ($A_{…

2023 Monthly Notices of the Royal Astronomical Society
Gaia 4
Far-ultraviolet Dust Extinction and Molecular Hydrogen in the Diffuse Milky Way Interstellar Medium
DOI: 10.3847/1538-4357/ac9902 Bibcode: 2023ApJ...944...33V

Gordon, Karl D.; Van De Putte, Dries; Cartledge, Stefan I. B. +2 more

We aim to compare variations in the full-UV dust extinction curve (912-3000 Å), with the H I/H2/total H content along diffuse Milky Way sightlines, to investigate possible connections between ISM conditions and dust properties. We combine an existing sample of 75 UV extinction curves based on IUE and FUSE data, with atomic and molecular…

2023 The Astrophysical Journal
Gaia IUE eHST 4