Search Publications
A free-form prediction for the reappearance of supernova Refsdal in the Hubble Frontier Fields cluster MACSJ1149.5+2223
Broadhurst, Tom; Zheng, Wei; Zitrin, Adi +7 more
The massive cluster MACSJ1149.5+2223(z = 0.544) displays five very large lensed images of a well-resolved spiral galaxy at zspect = 1.491. It is within one of these images that the first example of a multiply lensed supernova (SN) has been detected recently as part of the Grism Lens-Amplified Survey from Space. The depth of this data al…
Bayesian model selection without evidences: application to the dark energy equation-of-state
Hobson, M. P.; Lasenby, A. N.; Hee, S. +1 more
A method is presented for Bayesian model selection without explicitly computing evidences, by using a combined likelihood and introducing an integer model selection parameter n so that Bayes factors, or more generally posterior odds ratios, may be read off directly from the posterior of n. If the total number of models under consideration is speci…
A primordial origin for molecular oxygen in comets: a chemical kinetics study of the formation and survival of O2 ice from clouds to discs
van Dishoeck, E. F.; Walsh, C.; Taquet, V. +1 more
Molecular oxygen has been confirmed as the fourth most abundant molecule in cometary material (O2/H2O ∼ 4 per cent) and is thought to have a primordial nature, I.e. coming from the interstellar cloud from which our Solar system was formed. However, interstellar O2 gas is notoriously difficult to detect and has only…
The evolved-star dust budget of the Small Magellanic Cloud: the critical role of a few key players
Boyer, M. L.; Meixner, M.; Kemper, F. +3 more
The life cycle of dust in the interstellar medium is heavily influenced by outflows from asymptotic giant branch (AGB) and red supergiant (RSG) stars, a large fraction of which is contributed by a few very dusty sources. We compute the dust input to the Small Magellanic Cloud (SMC) by fitting the multi-epoch mid-infrared spectral energy distributi…
Dissecting galaxies: spatial and spectral separation of emission excited by star formation and AGN activity
Kewley, Lisa J.; Juneau, Stéphanie; Davies, Rebecca L. +13 more
The optical spectra of Seyfert galaxies are often dominated by emission lines excited by both star formation and active galactic nucleus (AGN) activity. Standard calibrations (such as for the star formation rate) are not applicable to such composite (mixed) spectra. In this paper, we describe how integral field data can be used to spectrally and s…
Spectral analysis of the XMM-Newton data of GX 339-4 in the low/hard state: disc truncation and reflection
Zdziarski, Andrzej A.; Basak, Rupal
We analyse all available observations of GX 339-4 by XMM-Newton in the hard spectral state. We jointly fit the spectral data by Comptonization and the currently best reflection code, relxill. We consider in detail a contribution from a standard blackbody accretion disc, testing whether its inner radius can be set equal to that of the reflector. Ho…
RPC observation of the development and evolution of plasma interaction boundaries at 67P/Churyumov-Gerasimenko
Coates, A. J.; Kallio, E.; Glassmeier, K. -H. +32 more
One of the primary objectives of the Rosetta Plasma Consortium, a suite of five plasma instruments on-board the Rosetta spacecraft, is to observe the formation and evolution of plasma interaction regions at the comet 67P/Churyumov-Gerasimenko (67P/CG). Observations made between 2015 April and 2016 February show that solar wind-cometary plasma inte…
The mass and spin of the extreme Narrow Line Seyfert 1 Galaxy 1H 0707-495 and its implications for the trigger for relativistic jets
Done, Chris; Jin, Chichuan
Relativistic reflection models of the X-ray spectrum of the `complex' Narrow Line Seyfert 1 (NLS1) 1H 0707-495 require a high-spin, moderate-inclination, low-mass black hole. With these parameters fixed, the observed optical/UV emission directly determines the mass accretion rate through the outer disc and hence predicts the bolometric luminosity.…
Furiously fast and red: sub-second optical flaring in V404 Cyg during the 2015 outburst peak
Altamirano, D.; Knigge, C.; Dhillon, V. S. +25 more
We present observations of rapid (sub-second) optical flux variability in V404 Cyg during its 2015 June outburst. Simultaneous three-band observations with the ULTRACAM fast imager on four nights show steep power spectra dominated by slow variations on ∼100-1000 s time-scales. Near the peak of the outburst on June 26, a dramatic change occurs and …
Baryon content of massive galaxy clusters at 0.57 < z < 1.33
Schrabback, T.; Zenteno, A.; Desai, S. +22 more
We study the stellar, brightest cluster galaxy (BCG) and intracluster medium (ICM) masses of 14 South Pole Telescope (SPT) selected galaxy clusters with median redshift z = 0.9 and mass M500 = 6 × 1014 M⊙. We estimate stellar masses for each cluster and BCG using six photometric bands, the ICM mass using X-ray obse…