Search Publications
Mapping the core of the Tarantula Nebula with VLT-MUSE - III. A template for metal-poor starburst regions in the visual and far-ultraviolet
Castro, N.; Crowther, Paul A.
We present the integrated VLT-MUSE spectrum of the central 2 × 2 arcmin2 (30 × 30 pc2) of NGC 2070, the dominant giant H II region of the Tarantula Nebula in the Large Magellanic Cloud, together with an empirical far-ultraviolet spectrum constructed via LMC template stars from the ULLYSES survey and Hubble Tarantula Treasury …
Oxygen abundance of γ Vel from [O III] 88 µm Herschel/PACS spectroscopy
Hillier, D. J.; Morris, P. W.; Barlow, M. J. +4 more
We present Herschel PACS spectroscopy of the [O III] 88.4 µm fine-structure line in the nearby WC8+O binary system γ Vel to determine its oxygen abundance. The critical density of this line corresponds to several 105R* such that it is spatially extended in PACS observations at the 336 pc distance to γ Vel. Two approache…
An ultraviolet spectral study of fullerene-rich planetary nebulae
García-Hernández, D. A.; Gómez-Muñoz, M. A.; Manchado, A. +2 more
Several planetary nebulae (PNe) have been found to contain both polycyclic aromatic hydrocarbon (PAH-like) species and fullerenes (C60) distinguished by their mid-infrared emission. Previous laboratory and astronomical studies suggest that the formation of both species could be related to the decomposition, by photochemical processing, …
The impact of periastron passage on the X-ray and optical properties of the Symbiotic System R Aquarii
Guerrero, M. A.; Toalá, J. A.; Karovska, M. +4 more
Multi-epoch Chandra and XMM-Newton observations of the symbiotic system R Aquarii (R Aqr) spanning 22 yr are analysed by means of a reflection model produced by an accretion disc. This methodology helps dissecting the contribution from different components in the X-ray spectra of R Aqr: the soft emission from the jet and extended emission, the hea…
Revisiting the accretion disc spectra of dwarf novae and nova-like variables: implications for the standard disc model
Pringle, J. E.; Naylor, T.; Zsidi, Gabriella +1 more
Accretion discs are fundamental to much of astronomy. They can occur around stars, both young and old, around compact objects they provide a window into the extremes of physics, and around supermassive black holes in galaxy centres, they generate spectacular luminosities that can outshine the entire galaxy. However, our understanding of the inner …
The 3D geometry of reflection nebulae IC 59 and IC 63 with their illuminating star gamma Cas
Lai, Thomas S. -Y.; Witt, Adolf N.; Caputo, Miranda +1 more
The early-type star gamma Cas illuminates the reflection nebulae IC 59 and IC 63, creating two photodissociation regions (PDRs). Uncertainties about the distances to the nebulae and the resulting uncertainty about the density of the radiation fields incident on their surfaces have hampered the study of these PDRs during the past three decades. We …
Multitechnique study of the B[e] supergiant RMC 82
Carciofi, A. C.; Seriacopi, D. B.; de Amorim, T. H. +9 more
B[e] supergiants (sgB[e]) are rare objects whose evolutionary stage remains uncertain. Observationally, they display strong Balmer emission lines, infrared excess, and intrinsic polarization, indicating a non-spherical circumstellar envelope. We present a study of the sgB[e] RMC 82, using new spectropolarimetric data complemented by photometry fro…
The B & V light curves for recurrent nova T CrB from 1842-2022, the unique pre- and post-eruption high-states, the complex period changes, and the upcoming eruption in 2025.5 ± 1.3
Schaefer, Bradley E.
T CrB is one of the most-famous and brightest novae known, and is a recurrent nova with prior eruptions in 1866 and 1946 that peak at V = 2.0. I have constructed light curves spanning 1842-2022 with 213 730 magnitudes, where the B and V magnitudes are fully corrected to the Johnson system. These light curves first reveal a unique complex high-stat…
Line luminosities of Galactic and Magellanic Cloud Wolf-Rayet stars
Crowther, Paul A.; Bestenlehner, Joachim M.; Rate, G.
We provide line luminosities and spectroscopic templates of prominent optical emission lines of 133 Galactic Wolf-Rayet (WR) stars by exploiting Gaia DR3 parallaxes and optical spectrophotometry, and provide comparisons with 112 counterparts in the Magellanic Clouds. Average line luminosities of the broad blue (He II λ4686, C III λλ4647,51, N III …
An HST COS ultraviolet spectroscopic survey of 311 DA white dwarfs - I. Fundamental parameters and comparative studies
Hermes, J. J.; Redfield, Seth; Sahu, Snehalata +8 more
White dwarf studies carry significant implications across multiple fields of astrophysics, including exoplanets, supernova explosions, and cosmological investigations. Thus, accurate determinations of their fundamental parameters (Teff and log g) are of utmost importance. While optical surveys have provided measurements for many white d…