Search Publications
J0526+5934: A peculiar ultra-short-period double white dwarf
Rebassa-Mansergas, Alberto; Hollands, Mark; Parsons, Steven G. +6 more
Context. Ultra-short-period compact binaries are important sources of gravitational waves. The class of short-period compact binaries includes, for example, the progenitors of type Ia supernovae and the progenitors of merger episodes that may lead to massive and magnetic single white dwarfs. J0526+5934 is one such example: it is an unresolved comp…
Astrometry and Precise Radial Velocities Yield a Complete Orbital Solution for the Nearby Eccentric Brown Dwarf LHS 1610 b
Callingham, J. R.; Cochran, William D.; Mahadevan, Suvrath +18 more
The LHS 1610 system consists of a nearby (d = 9.7 pc) M5 dwarf hosting a candidate brown dwarf companion in a 10.6 days, eccentric (e ∼ 0.37) orbit. We confirm this brown dwarf designation and estimate its mass (
INTEGRAL view of GRB 221009A. Prompt energetics and week-long hard X-ray afterglow
Mereghetti, Sandro; Tiengo, Andrea; Kuulkers, Erik +11 more
The gamma-ray burst GRB 221009A is among the most luminous of its kind and its proximity to Earth has made it an exceptionally rare observational event. The International Gamma-ray Astrophysics Laboratory (INTEGRAL) was in an optimal aspect position to use its all-sky instruments for recording the prompt emission and early gamma-ray afterglow in u…
Chemical Cartography with APOGEE: Two-process Parameters and Residual Abundances for 288,789 Stars from Data Release 17
Masseron, Thomas; Hayes, Christian R.; Sit, Tawny +4 more
Stellar abundance measurements are subject to systematic errors that induce extra scatter and artificial correlations in elemental abundance patterns. We derive empirical calibration offsets to remove systematic trends with surface gravity
Survey of extended main-sequence turn-offs in galactic open clusters: stellar rotations from Gaia RVS spectra
Milone, A. P.; Cordoni, G.; Marino, A. F. +6 more
The origin of extended main-sequence turn-offs (eMSTO) in star clusters younger than 2 Gyr still challenges our current understanding of stellar evolution. Exploiting data from Gaia Data Release 3 (DR3), we investigate eMSTOs in a large sample of 32 Galactic open clusters younger than 2.4 Gyr. We first validate Gaia rotational velocities from radi…
Variation of the electron flux spectrum along a solar flare loop as inferred from STIX hard X-ray observations
Volpara, Anna; Massa, Paolo; Krucker, Säm +3 more
Context. Regularized imaging spectroscopy was introduced for the construction of electron flux images at different energies from count visibilities recorded by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). In this work we seek to extend this approach to data from the Spectrometer/Telescope for Imaging X-rays (STIX) on board th…
JWST Observations of Starbursts: Massive Star Clusters in the Central Starburst of M82
Boogaard, Leindert A.; Meier, David S.; Böker, Torsten +25 more
We present a near-infrared (NIR) candidate star cluster catalog for the central kiloparsec of M82 based on new JWST NIRCam images. We identify star cluster candidates using the F250M filter, finding 1357 star cluster candidates with stellar masses >104 M ⊙. Compared to previous optical catalogs, nearly all (87%) of the can…
Searching for Planets Orbiting Fomalhaut with JWST/NIRCam
Johnstone, Doug; Rieke, George H.; Krist, John E. +20 more
We report observations with the JWST/NIRCam coronagraph of the Fomalhaut (α PsA) system. This nearby A star hosts a complex debris disk system discovered by the IRAS satellite. Observations in F444W and F356W filters using the round 430R mask achieve a contrast ratio of ~4 × 10-7 at 1″ and ~4 × 10-8 outside of 3″. These obser…
Three sub-Jovian-mass microlensing planets: MOA-2022-BLG-563Lb, KMT-2023-BLG-0469Lb, and KMT-2023-BLG-0735Lb
Han, Cheongho; Lee, Chung-Uk; Zang, Weicheng +45 more
Aims: We analyze the anomalies appearing in the light curves of the three microlensing events MOA-2022-BLG-563, KMT-2023-BLG-0469, and KMT-2023-BLG-0735. The anomalies exhibit common short-term dip features that appear near the peak.
Methods: From the detailed analyses of the light curves, we find that the anomalies were produced by plan…
Deep JWST/NIRCam imaging of Supernova 1987A
Larsson, J.; Lundqvist, P.; Spyromilio, J. +46 more
JWST/NIRCam obtained high angular resolution (0.05-0.1 arcsec), deep near-infrared 1-5 $\mu$m imaging of Supernova (SN) 1987A taken 35 yr after the explosion. In the NIRCam images, we identify: (1) faint H2 crescents, which are emissions located between the ejecta and the equatorial ring, (2) a bar, which is a substructure of the ejecta…