Search Publications
Nitrogen enrichment and clustered star formation at the dawn of the Galaxy
Belokurov, Vasily; Kravtsov, Andrey
Anomalously high nitrogen-to-oxygen abundance ratios [N/O] are observed in globular clusters (GCs), among the field stars of the Milky Way (MW), and even in the gas in a z ≈ 11 galaxy. Using data from the APOGEE Data Release 17 and the Gaia Data Release 3, we present several independent lines of evidence that most of the MW's high-[N/O] stars were…
ALMA confirmation of an obscured hyperluminous radio-loud AGN at z = 6.853 associated with a dusty starburst in the 1.5 deg2 COSMOS field
Fan, Xiaohui; Stark, Daniel P.; Endsley, Ryan +7 more
We present band 6 ALMA observations of a heavily obscured radio-loud (L1.4 GHz = 1025.4 W Hz-1) active galactic nucleus (AGN) candidate at zphot = 6.83 ± 0.06 found in the 1.5 deg2 COSMOS field. The ALMA data reveal detections of exceptionally strong [C II]158 $\mu$m (z[C II] = 6.85…
The abundance of z ≳ 10 galaxy candidates in the HUDF using deep JWST NIRCam medium-band imaging
Cullen, F.; McLure, R. J.; Dunlop, J. S. +4 more
We utilize JWST NIRCam medium-band imaging to search for extreme redshift (z ≥ 9.5) galaxy candidates in the Hubble ultra deep field (HUDF) and the additional pointing within the GOODS-South field provided by the second NIRCam module. Our search reveals six robust candidates, three of which have recently been spectroscopically confirmed. One of th…
STRIDES: automated uniform models for 30 quadruply imaged quasars
Bacon, D.; Smith, M.; Annis, J. +69 more
Gravitational time delays provide a powerful one-step measurement of H0, independent of all other probes. One key ingredient in time-delay cosmography are high-accuracy lens models. Those are currently expensive to obtain, both, in terms of computing and investigator time (105-106 CPU hours and ~0.5-1 yr, respectiv…
JWST/NIRCam observations of stars and H II regions in z ≃ 6-8 galaxies: properties of star-forming complexes on 150 pc scales
Charlot, Stéphane; Chen, Zuyi; Stark, Daniel P. +3 more
The onset of the JWST-era provides a much-improved opportunity to characterize the resolved structure of early star-forming systems. Previous Spitzer observations of z ≳ 6 galaxies revealed the presence of old stars and luminous H II regions (via [O III]+H β emission), but the poor resolution stunted our ability to map their locations with respect…
The occurrence rate of giant planets orbiting low-mass stars with TESS
Bayliss, Daniel; Van Eylen, Vincent; Bryant, Edward M.
We present a systematic search for transiting giant planets ($0.6 \mbox{$R_{\rm J}$}\le \mbox{$R_{\rm P}$}\le 2.0 \mbox{$R_{\rm J}$}$) orbiting nearby low-mass stars ($\mbox{$M_{*}$}\le 0.71 \mbox{${\rm M}_{\odot }$}$). The formation of giant planets around low-mass stars is predicted to be rare by the core-accretion planet formation theory. We se…
Gamma-ray bursts, quasars, baryonic acoustic oscillations, and supernovae Ia: new statistical insights and cosmological constraints
Nagataki, S.; Bargiacchi, G.; Capozziello, S. +1 more
The recent $\sim 4 \, \sigma$ Hubble constant, H0, tension is observed between the value of H0 from the cosmic microwave background (CMB) and Type Ia supernovae (SNe Ia). It is a decade since this tension is excruciating the modern astrophysical community. To shed light on this problem is key to consider probes at intermediat…
Uncovering the geometry of the hot X-ray corona in the Seyfert galaxy NGC 4151 with IXPE
Antonelli, L. A.; Costa, E.; Bianchi, S. +106 more
We present an X-ray spectropolarimetric analysis of the bright Seyfert galaxy NGC 4151. The source has been observed with the Imaging X-ray Polarimetry Explorer (IXPE) for 700 ks, complemented with simultaneous XMM-Newton (50 ks) and NuSTAR (100 ks) pointings. A polarization degree Π = 4.9 ± 1.1 per cent and angle Ψ = 86° ± 7° east of north (68 pe…
The ASAS-SN catalogue of variable stars X: discovery of 116 000 new variable stars using G-band photometry
Kochanek, C. S.; Stanek, K. Z.; Dong, Subo +7 more
The All-Sky Automated Survey for Supernovae (ASAS-SN) is the first optical survey to monitor the entire sky, currently with a cadence of ≲ 24 h down to g ≲ 18.5 mag. ASAS-SN has routinely operated since 2013, collecting ~ 2 000 to over 7 500 epochs of V- and g-band observations per field to date. This work illustrates the first analysis of ASAS-SN…
A measurement of the distance to the Galactic centre using the kinematics of bar stars
Bovy, Jo; Mackereth, J. Ted; Hunt, Jason A. S. +3 more
The distance to the Galactic centre R0 is a fundamental parameter for understanding the Milky Way, because all observations of our Galaxy are made from our heliocentric reference point. The uncertainty in R0 limits our knowledge of many aspects of the Milky Way, including its total mass and the relative mass of its major comp…