Search Publications

An Asymmetric Dust Ring around a Very Low Mass Star ZZ Tau IRS
DOI: 10.3847/1538-3881/abf431 Bibcode: 2021AJ....161..264H

Dong, Ruobing; Hashimoto, Jun; Muto, Takayuki

We present Atacama Large Millimeter/submillimeter Array (ALMA) gas and dust observations at band 7 (339 GHz: 0.89 mm) of the protoplanetary disk around a very low mass star ZZ Tau IRS with a spatial resolution of 0"25. The 12CO J = 3 → 2 position-velocity diagram suggests a dynamical mass of ZZ Tau IRS of ∼0.1-0.3 M. The dis…

2021 The Astronomical Journal
Gaia 15
Massive young stellar objects in the Local Group irregular galaxy NGC 6822 identified using machine learning
DOI: 10.1093/mnras/stab2386 Bibcode: 2021MNRAS.507.5106K

van Loon, Jacco Th; Oliveira, Joana M.; Kinson, David A.

We present a supervised machine learning methodology to classify stellar populations in the Local Group dwarf-irregular galaxy NGC 6822. Near-IR colours (J - H, H - K, and J - K), K-band magnitudes and far-IR surface brightness (at 70 and 160 $\mu$m) measured from Spitzer and Herschel images are the features used to train a Probabilistic Random Fo…

2021 Monthly Notices of the Royal Astronomical Society
Gaia Herschel 15
The dependence of the hierarchical distribution of star clusters on galactic environment
DOI: 10.1093/mnras/stab2413 Bibcode: 2021MNRAS.507.5542M

Grebel, Eva K.; Smith, Linda J.; Calzetti, Daniela +15 more

We use the angular two-point correlation function (TPCF) to investigate the hierarchical distribution of young star clusters in 12 local (3-18 Mpc) star-forming galaxies using star cluster catalogs obtained with the Hubble Space Telescope (HST) as part of the Treasury Program Legacy ExtraGalactic UV Survey. The sample spans a range of different mo…

2021 Monthly Notices of the Royal Astronomical Society
eHST 15
Physical characterization of recently discovered globular clusters in the Sagittarius dwarf spheroidal galaxy. I. Metallicities, ages, and luminosities
DOI: 10.1051/0004-6361/202141067 Bibcode: 2021A&A...654A..23G

Minniti, D.; Alonso-García, J.; Gómez, M. +1 more

Context. Globular clusters (GCs) are important tools for rebuilding the accretion history of a galaxy. In particular, newly discovered GCs in the Sagittarius (Sgr) dwarf galaxy can be used as probes of the accretion event onto the Milky Way (MW).
Aims: Our main aim is to characterize the GC system of the Sgr dwarf galaxy by measuring its main…

2021 Astronomy and Astrophysics
Gaia 15
Tracing the Milky Way's Vestigial Nuclear Jet
DOI: 10.3847/1538-4357/ac224f Bibcode: 2021ApJ...922..254C

Bland-Hawthorn, Joss; Mukherjee, Dipanjan; Wagner, Alexander Y. +2 more

MeerKAT radio continuum and XMM-Newton X-ray images have recently revealed a spectacular bipolar channel at the Galactic Center that spans several degrees (~0.5 kpc). An intermittent jet likely formed this channel and is consistent with earlier evidence of a sustained, Seyfert-level outburst fueled by black hole accretion onto Sgr A* several Myr a…

2021 The Astrophysical Journal
eHST 15
Searching for new solar twins: The Inti survey for the Northern Sky
DOI: 10.1093/mnras/stab987 Bibcode: 2021MNRAS.504.1873Y

Meléndez, Jorge; Reggiani, Henrique; Schlaufman, Kevin C. +9 more

Solar twins are key in different areas of astrophysics, however only just over a hundred were identified and well-studied in the last two decades. In this work, we take advantage of the very precise Gaia (DR2/EDR3), Tycho, and 2MASS photometric systems to create the ${{Inti}}$ survey of new solar twins in the Northern Hemisphere. The spectra of ou…

2021 Monthly Notices of the Royal Astronomical Society
Gaia Hipparcos 15
Calibrating X-Ray Binary Luminosity Functions via Optical Reconnaissance. I. The Case of M83
DOI: 10.3847/1538-4357/abe531 Bibcode: 2021ApJ...912...31H

Chandar, Rupali; Mok, Angus; Gallo, Elena +4 more

Building on recent work by Chandar et al., we construct X-ray luminosity functions (XLFs) for different classes of X-ray binary (XRB) donors in the nearby star-forming galaxy M83 through a novel methodology. Rather than classifying low- versus high-mass XRBs based on the scaling of the number of X-ray sources with stellar mass and star formation r…

2021 The Astrophysical Journal
eHST 15
Structure and dynamics of the inner nebula around the symbiotic stellar system R Aquarii
DOI: 10.1051/0004-6361/202141002 Bibcode: 2021A&A...651A...4B

Alcolea, J.; Santander-García, M.; Bujarrabal, V. +5 more


Aims: We investigate the structure, dynamics, and chemistry of the molecule-rich nebula around the stellar symbiotic system R Aqr, which is significantly affected by the presence of a white dwarf (WD) companion. We study the effects of the strong dynamical interaction between the AGB wind and the WD and of photodissociation by the WD UV radia…

2021 Astronomy and Astrophysics
IUE 15
StrayCats: A Catalog of NuSTAR Stray Light Observations
DOI: 10.3847/1538-4357/abe045 Bibcode: 2021ApJ...909...30G

Hare, Jeremy; García, Javier A.; Madsen, Kristin K. +10 more

We present StrayCats, a catalog of NuSTAR stray light observations of X-ray sources. Stray light observations arise for sources 1°-4° away from the telescope pointing direction. At this off-axis angle, X-rays pass through a gap between the optics and aperture stop and so do not interact with the X-ray optics; instead, they directly illuminate the …

2021 The Astrophysical Journal
INTEGRAL 15
Statistical analysis of soft X-ray solar flares during solar cycles 22, 23, and 24
DOI: 10.1007/s10509-020-03909-z Bibcode: 2021Ap&SS.366....1X

Xiong, Bo; Li, Xiaolin; Wang, Ting +1 more

This paper presents a statistical analysis of soft X-ray flares during the period January 1986 to June 2017 covering the last three solar cycles (SCs) 22, 23, and 24. We have analyzed the distribution of flare number, the relationship between the occurrence rate of soft X-ray flares and solar activity, and the duration of different intensity class…

2021 Astrophysics and Space Science
SOHO 15