Search Publications
H2S in the L1157-B1 bow shock
Viti, Serena; Bachiller, Rafael; Ceccarelli, Cecilia +8 more
Sulphur-bearing molecules are highly reactive in the gas phase of the interstellar medium. However, the form in which most of the sulphur is locked on to interstellar dust grains is unknown. By taking advantage of the short time-scales of shocks in young molecular outflows, one could track back the main form of sulphur in the ices. In this paper, …
Structure and stability in TMC-1: Analysis of NH3 molecular line and Herschel continuum data
Kirk, J.; Ward-Thompson, D.; Kraus, A. +5 more
Aims: We examined the velocity, density, and temperature structure of Taurus molecular cloud-1 (TMC-1), a filamentary cloud in a nearby quiescent star forming area, to understand its morphology and evolution.
Methods: We observed high signal-to-noise (S/N), high velocity resolution NH3(1,1), and (2, 2) emission on an extended …
Abundance stratification in Type Ia supernovae - V. SN 1986G bridging the gap between normal and subluminous SNe Ia
Pian, E.; Ashall, C.; Mazzali, P. A. +1 more
A detailed spectroscopic analysis of SN 1986G has been performed. SN 1986G `bridges the gap' between normal and subluminous Type Ia supernovae (SNe Ia). The abundance tomography technique is used to determine the abundance distribution of the elements in the ejecta. SN 1986G was found to be a low-energy Chandrasekhar mass explosion. Its kinetic en…
Explaining the reportedly overmassive black holes in early-type galaxies with intermediate-scale discs
Graham, Alister W.; Savorgnan, Giulia A. D.
The classification `early-type' galaxy includes both elliptically and lenticular-shaped galaxies. Theoretically, the spheroid-to-disc flux ratio of an early-type galaxy can assume any positive value, but in practice studies often consider only spheroid/disc decompositions in which the disc neatly dominates over the spheroid at large galaxy radii, …
The formation of bulges, discs and two-component galaxies in the CANDELS Survey at z < 3
Conselice, Christopher J.; Mortlock, Alice; Dekel, Avishai +5 more
We examine a sample of 1495 galaxies in the CANDELS fields to determine the evolution of two-component galaxies, including bulges and discs, within massive galaxies at the epoch 1 < z < 3 when the Hubble sequence forms. We fit all of our galaxies' light profiles with a single Sérsic fit, as well as with a combination of exponential and Sérsi…
Characterizing X-Ray and Radio Emission in the Black Hole X-Ray Binary V404 Cygni during Quiescence
Gandhi, Poshak; Chakrabarty, Deepto; Walton, Dominic J. +17 more
We present results from multi-wavelength simultaneous X-ray and radio observations of the black hole X-ray binary V404 Cyg in quiescence. Our coverage with NuSTAR provides the very first opportunity to study the X-ray spectrum of V404 Cyg at energies above 10 keV. The unabsorbed broadband (0.3-30 keV) quiescent luminosity of the source is 8.9 × 10…
The HerMES submillimetre local and low-redshift luminosity functions
Aussel, H.; Pérez-Fournon, I.; Valtchanov, I. +43 more
We used wide-area surveys over 39 deg2 by the HerMES (Herschel Multi-tiered Extragalactic Survey) collaboration, performed with the Herschel Observatory SPIRE multiwavelength camera, to estimate the low-redshift, 0.02 < z < 0.5, monochromatic luminosity functions (LFs) of galaxies at 250, 350 and 500 µm. Within this redshift…
Herschel-resolved Outer Belts of Two-belt Debris Disks—Evidence of Icy Grains
Bryden, G.; Stapelfeldt, K. R.; Werner, M. W. +1 more
We present dual-band Herschel/PACS imaging for 59 main-sequence stars with known warm dust (T warm ∼ 200 K), characterized by Spitzer. Of 57 debris disks detected at Herschel wavelengths (70 and/or 100 and 160 µm), about half have spectral energy distributions (SEDs) that suggest two-ring disk architectures mirroring that of the a…
X-ray detection of warm ionized matter in the Galactic halo
Piro, L.; Guainazzi, M.; Elvis, M. +5 more
We report on a systematic investigation of the cold and mildly ionized gaseous baryonic metal components of our Galaxy, through the analysis of high-resolution Chandra and XMM-Newton spectra of two samples of Galactic and extragalactic sources. The comparison between lines of sight towards sources located in the disc of our Galaxy and extragalacti…
Broad-band spectral analysis of the accreting millisecond X-ray pulsar SAX J1748.9-2021
Sanna, A.; Di Salvo, T.; Burderi, L. +6 more
We analysed a 115-ks XMM-Newton observation and the stacking of 8 d of INTEGRAL observations, taken during the raise of the 2015 outburst of the accreting millisecond X-ray pulsar SAX J1748.9-2021. The source showed numerous type-I burst episodes during the XMM-Newton observation, and for this reason we studied separately the persistent and burst …