Search Publications
Discovery of 2716 hot emission-line stars from LAMOST DR5
Mathew, Blesson; Kartha, Sreeja S.; Kumar, Yerra Bharat +4 more
We present a catalog of 3339 hot emission-line stars (ELSs) identified from 451 695 O, B and A type spectra, provided by LAMOST Data Release 5 (DR5). We developed an automated Python routine that identified 5437 spectra having a peak between 6561 and 6568 Å. False detections and bad spectra were removed, leaving 4138 good emission-line spectra of …
Anomalous gas in ESO 149-G003: a MeerKAT-16 view
Józsa, Gyula I. G.; Wang, Jing; Paterson, Kerry +28 more
ESO 149-G003 is a close-by, isolated dwarf irregular galaxy. Previous observations with the ATCA indicated the presence of anomalous neutral hydrogen ( $\rm{H{\small I}}$ ) deviating from the kinematics of a regularly rotating disc. We conducted follow-up observations with the MeerKAT radio telescope during the 16-dish Early Science programme as w…
The total solar irradiance during the recent solar minimum period measured by SOHO/VIRGO
Schmutz, W.; Finsterle, W.; Montillet, J. P. +3 more
Various space missions have measured the total solar irradiance (TSI) since 1978. Among them the experiments Precision Monitoring of Solar Variability (PREMOS) on the PICARD satellite (2010-2014) and the Variability of Irradiance and Gravity Oscillations (VIRGO) on the mission Solar and Heliospheric Observatory, which started in 1996 and is still …
Combining white light and UV Lyman-α coronagraphic images to determine the solar wind speed. The quick inversion method
Bemporad, A.; Frassati, F.; Giordano, S. +1 more
Context. The availability of multi-channel coronagraphic images in different wavelength intervals acquired from the space will provide a new view of the solar corona, allowing us to investigate the 2D distribution and time evolution of many plasma physical parameters, such as plasma density, temperature, and outflow speed.
Aims: This work foc…
Rotation Periods of TESS Objects of Interest from the Magellan-TESS Survey with Multiband Photometry from Evryscope and TESS
Law, Nicholas M.; Teske, Johanna; Wang, Sharon Xuesong +8 more
Stellar radial-velocity (RV) jitter due to surface activity may bias the RV semiamplitude and mass of rocky planets. The amplitude of the jitter may be estimated from the uncertainty in the rotation period, allowing the mass to be more accurately obtained. We find candidate rotation periods for 17 out of 35 TESS Objects of Interest (TOI) hosting &…
Disintegration of Long-period Comet C/2019 Y4 (ATLAS). I. Hubble Space Telescope Observations
Mutchler, Max; Weaver, Harold A.; Jewitt, David +8 more
The near-Sun comet C/2019 Y4 (ATLAS) is the first member of a long-period comet group observed to disintegrate well before perihelion. Here we present our investigation into this disintegration event using images obtained in a three-day Hubble Space Telescope campaign. We identify two fragment clusters produced by the initial disintegration event,…
Discovery of a multiphase O VI and O VII absorber in the circumgalactic/intergalactic transition region
Finoguenov, Alexis; Schaye, Joop; Muzahid, Sowgat +4 more
Aims: The observational constraints on the baryon content of the warm-hot intergalactic medium (WHIM) rely almost entirely on far ultraviolet (FUV) measurements. However, cosmological, hydrodynamical simulations predict strong correlations between the spatial distributions of FUV and X-ray absorbing WHIM. We investigate this prediction by ana…
Exploring the planetary-mass population in the Upper Scorpius association
Hambly, N. C.; Lodieu, N.; Cross, N. J. G.
We aim at identifying very low-mass isolated planetary-mass member candidates in the nearest OB association to the Sun, Upper Scorpius (USco) (145 pc; 5-10 Myr), to constrain the form and shape of the luminosity function and mass spectrum in this regime. We conducted a deep multiband (Y = 21.2, J = 20.5, Z = 22.0 mag) photometric survey of 6 deg
Searching for energy-resolved quasi-periodic oscillations in AGN
Middleton, Matthew J.; Ashton, Dominic I.
X-ray quasi-periodic oscillations (QPOs) in active galactic nucleus (AGN) allow us to probe and understand the nature of accretion in highly curved space-time, yet the most robust form of detection (i.e. repeat detections over multiple observations) has been limited to a single source to-date, with only tentative claims of single observation detec…
Parsec-scale alignments of radio-optical offsets with jets in AGNs from multifrequency geodetic VLBI, Gaia EDR3, and the MOJAVE program
Liu, N.; Zhu, Z.; Barache, C. +5 more
Aims: We aim to study the relative positions of quasar emission centers at different wavelengths in order to help link the various realizations of the International Celestial Reference System (ICRS), and to unveil systematic uncertainties and individual source behavior at different wavelengths.
Methods: We based our study on four catalog…