Search Publications
Simulating cosmological substructure in the solar neighbourhood
Grand, Robert J. J.; Gómez, Facundo A.; Marinacci, Federico +8 more
We explore the predictive power of cosmological, hydrodynamical simulations for stellar phase-space substructure and velocity correlations with the AURIGA simulations and AURIGAIA mock Gaia catalogues. We show that at the solar circle the AURIGA simulations commonly host phase-space structures in the stellar component that have constant orbital en…
TT Arietis: 40 yr of photometry
Bruch, Albert
In an effort to characterize variations on the time-scale of hours and smaller during the high and low states of the nova-like variable TT Ari, light curves taken over the course of more than 40 yr are analysed. It is found that the well-known negative superhump observed during the high state persists until the present day at an average period of …
Evidence for a clumpy disc-wind in the star-forming Seyfert 2 galaxy MCG-03-58-007
Campana, S.; Schartel, N.; Santos-Lleó, M. +9 more
We report the results of a detailed analysis of a deep simultaneous 130 ksXMM-Newton and NuSTAR observation of the nearby (z = 0.0315) and bright (L_bol∼ 3× 10^{45} erg s^{-1}) starburst-active galactic nucleus (AGN) Seyfert 2 system: MCG-03-58-007. From the broad-band fitting we show that most of the obscuration needs to be modelled with a toroid…
Molecular envelope around the HII region RCW 120
Wiebe, D. S.; Anderson, L. D.; Kirsanova, M. S. +5 more
The H II region RCW 120 is a well-known object, which is often considered as a target to verify theoretical models of gas and dust dynamics in the interstellar medium. However, the exact geometry of RCW 120 is still a matter of debate. In this work, we analyse observational data on molecular emission in RCW 120 and show that 13CO(2-1) a…
Using deep Residual Networks to search for galaxy-Ly α emitter lens candidates based on spectroscopic selection
Wang, Jiancheng; Shu, Yiping; Li, Rui +4 more
More than 100 galaxy-scale strong gravitational lens systems have been found by searching for the emission lines coming from galaxies with redshifts higher than the lens galaxies. Based on this spectroscopic-selection method, we introduce the deep Residual Networks (ResNet; a kind of deep Convolutional Neural Networks) to search for the galaxy-Ly …
SOFIA/FORCAST resolves 30-40 µm extended dust emission in nearby active galactic nuclei
Togi, Aditya; Alonso-Herrero, Almudena; Fuller, Lindsay +7 more
We present arcsecond-scale observations of the active galactic nuclei (AGNs) of seven nearby Seyfert galaxies observed from the Stratospheric Observatory For Infrared Astronomy (SOFIA) using the 31.5 and 37.1 µm filters of the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST). We isolate unresolved emission from the torus and fi…
Multiwavelength observations of the EUV variable metal-rich white dwarf GD 394
Redfield, Seth; Casewell, Sarah L.; Burleigh, Matthew R. +13 more
We present new Hubble Space Telescope (HST) ultraviolet and ground-based optical observations of the hot, metal-rich white dwarf GD 394. Extreme-ultraviolet (EUV) observations in 1992-1996 revealed a 1.15 d periodicity with a 25 per cent amplitude, hypothesized to be due to metals in a surface accretion spot. We obtained phase resolved HST/Space T…
The GALAH Survey: lithium-strong KM dwarfs
Zwitter, T.; Buder, S.; Casagrande, L. +10 more
Identifying and characterizing young stars in the Solar neighbourhood is essential to find and describe planets in the early stages of their evolution. This work seeks to identify nearby young stars showing a lithium 6708 Å absorption line in the GALAH survey. A robust, data-driven approach is used to search for corresponding templates in the pool…
C IV absorbers tracing cool gas in dense galaxy group/cluster environments
Charlton, Jane C.; Muzahid, Sowgat; Narayanan, Anand +3 more
We present analysis on three intervening H I-C IV absorption systems tracing gas within galaxy group/cluster environments, identified in the HST/COS far-UV spectra of the background quasars PG 1148 + 549 (zabs = 0.003 46), SBS 1122 + 594 (zabs = 0.004 02), and RXJ 1230.8 + 0115 (zabs = 0.005 74). The ionization mod…
Hemispheric asymmetry in meridional flow and the sunspot cycle
Antia, H. M.; Nandy, Dibyendu; Lekshmi, B.
Magnetohydrodynamic dynamo modelling shows that the large-scale solar meridional plasma flow plays an important role in governing the dynamics of the sunspot cycle. Observations indicate that meridional flow velocities at each solar latitude and depth vary over time and are asymmetric across the equator. Here, using helioseismic observations we ex…