Search Publications
Unveiling Luminous Lyα Emitters at z ≈ 6 through JWST/NIRCam Imaging in the COSMOS Field
Ning, Yuanhang; Cai, Zheng; Lin, Xiaojing +7 more
We study a sample of 14 spectroscopically confirmed Lyα emitters (LAEs) in the late era of reionization (at redshift z ≈ 6) based on the JWST/NIRCam imaging data set. These LAEs with high Lyα luminosity of L(Lyα) ∼1042.4–1043.4 erg s‑1 have been covered by the (ongoing) COSMOS-Web survey over 0.28 deg2 i…
SN 2020pvb: A Type IIn-P supernova with a precursor outburst
Lundqvist, P.; Gal-Yam, A.; Geier, S. +37 more
We present photometric and spectroscopic datasets for SN 2020pvb, a Type IIn-P supernova (SN) that is similar to SNe 1994W, 2005cl, 2009kn, and 2011ht, with a precursor outburst detected (PS1 w band ∼-13.8 mag) around four months before the B-band maximum light. SN 2020pvb presents a relatively bright light curve that peaked at MB = −17…
Methane emission from a cool brown dwarf
Kiman, Rocio; Kirkpatrick, J. Davy; Gelino, Christopher R. +21 more
Beyond our Solar System, aurorae have been inferred from radio observations of isolated brown dwarfs1,2. Within our Solar System, giant planets have auroral emission with signatures across the electromagnetic spectrum including infrared emission of H3+ and methane. Isolated brown dwarfs with auroral signatures in t…
Large exomoons unlikely around Kepler-1625 b and Kepler-1708 b
Heller, René; Hippke, Michael
There are more than 200 moons in our Solar System, but their relatively small radii make similarly sized extrasolar moons very hard to detect with current instruments. The best exomoon candidates so far are two nearly Neptune-sized bodies orbiting the Jupiter-sized transiting exoplanets Kepler-1625 b and Kepler-1708 b, but their existence has been…
A survey for radio emission from white dwarfs in the VLA Sky Survey
Dhillon, V. S.; Strader, Jay; Dage, Kristen C. +22 more
Radio emission has been detected from tens of white dwarfs, in particular in accreting systems. Additionally, radio emission has been predicted as a possible outcome of a planetary system around a white dwarf. We searched for 3 GHz radio continuum emission in 846 000 candidate white dwarfs previously identified in Gaia using the Very Large Array S…
Axisymmetric High Spot Coverage on Exoplanet Host HD 189733 A
Rackham, Benjamin V.; de Wit, Julien; Narrett, Isaac S.
Transmission spectroscopy is a powerful tool to study exoplanet atmospheres, which can be affected by the ability of stellar photospheric heterogeneity to mimic or mask exoplanetary spectral signatures. The canonical HD 189733 system provides a textbook example of this spectroscopic discrepancy with features that have been variously interpreted as…
Coordinated JWST Imaging of Three Distance Indicators in a Supernova Host Galaxy and an Estimate of the Tip of the Red Giant Branch Color Dependence
Madore, Barry F.; Freedman, Wendy L.; Jang, In Sung +3 more
Boasting a 6.5 m mirror in space, JWST can increase by several times the number of supernovae (SNe) to which a redshift-independent distance has been measured with a precision distance indicator (e.g., tip of the red giant branch (TRGB) or Cepheids); the limited number of such SN calibrators currently dominates the uncertainty budget in distance l…
Reanalysis of the MACHO Constraints on PBH in the Light of Gaia DR3 Data
García-Bellido, Juan; Hawkins, Michael
The recent astrometric data of hundreds of millions of stars from Gaia DR3 has allowed for a precise determination of the Milky Way rotation curve up to 28 kpc. The data suggest a rapid decline in the density of dark matter beyond 19 kpc. We fit the whole rotation curve with four components (gas, disk, bulge, and halo), and compute the microlensin…
G321.3–3.9: A new supernova remnant observed with multi-band radio data and in the SRG/eROSITA All-Sky Surveys
Nicastro, L.; Becker, W.; Hurley-Walker, N. +3 more
Aims. G321.3–3.9 was first identified as a partial shell at radio frequencies a few decades ago. Although it continued to be observed, no additional studies were undertaken until recently. Methods. In this paper, we present results from a large selection of radio and X-ray data that cover the position of G321.3–3.9. We confirmed G321.3–3.9 as a ne…
The positional probability and true host star identification of TESS exoplanet candidates
Armstrong, David J.; Hadjigeorghiou, Andreas
We present a method for deriving a probabilistic estimate of the true source of a detected TESS transiting event. Our method relies on comparing the observed photometric centroid offset for the target star with models of the offset that would occur if the event was either on the target or any of the Gaia identified nearby sources. The comparison i…