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H α fluxes and extinction distances for planetary nebulae in the IPHAS survey of the northern galactic plane
Barlow, M. J.; Sabin, L.; Jones, D. +7 more
We report H α filter photometry for 197 Northern hemisphere planetary nebulae (PNe) obtained using imaging data from the IPHAS survey. H α+[N II] fluxes were measured for 46 confirmed or possible PNe discovered by the IPHAS survey and for 151 previously catalogued PNe that fell within the area of the northern Galactic Plane surveyed by IPHAS. Afte…
The first spectroscopically confirmed brown dwarfs in NGC 2264
Scholz, Aleks; Teixeira, Paula S.; Mužić, Koraljka +2 more
We present spectroscopic follow-up observations of 68 red, faint candidates from our multi-epoch, multiwavelength, previously published survey of NGC 2264. Using near-infrared spectra from VLT/KMOS, we measure spectral types and extinction for 32 young low-mass sources. We confirm 13 as brown dwarfs in NGC 2264, with spectral types between M6 and …
Fast synthetic spectral fitting for large stellar samples: a critical test with 25 bright stars of known rotation
Snellen, I.; Schröder, K. -P.; Mittag, M. +2 more
This work presents and tests a reliable, but nonetheless fast, method for determining the physical parameters of large stellar samples with moderate-resolution spectra, with extensive host star-exoplanet studies in mind. The proposed strategy complements spectral synthesis for obtaining spectroscopically sensitive parameters (i.e. effective temper…
Estimating the age-metallicity distribution of a stellar sample from the probability distributions of the individual stars
Lindegren, Lennart; Sahlholdt, Christian L.
Estimating age distributions, or star formation histories, of stellar populations in the Milky Way is important in order to study the evolution of trends in elemental abundances and kinematics. We build on previous work to develop an algorithm for estimating the age-metallicity distribution which uses the full age-metallicity probability density f…
Probing the spectral shape of dust emission with the DustPedia galaxy sample
Clark, Christopher J. R.; Mosenkov, Aleksandr V.; De Looze, Ilse +10 more
The objective of this paper is to understand the variance of the far-infrared (FIR) spectral energy distribution (SED) of the DustPedia galaxies, and its link with the stellar and dust properties. An interesting aspect of the dust emission is the inferred FIR colours which could inform us about the dust content of galaxies, and how it varies with …
Detecting episodes of star formation using Bayesian model selection
Acquaviva, Viviana; Lawler, Andrew J.
Bayesian model comparison frameworks can be used when fitting models to data in order to infer the appropriate model complexity in a data-driven manner. We aim to use them to detect the correct number of major episodes of star formation from the analysis of the spectral energy distributions (SEDs) of galaxies, modelled after 3D-HST galaxies at z ∼…
Long-term XMM-Newton view of magnetar CXOU J010043.1-721134: comprehensive spectral and temporal results
Chatterjee, Rwitika; Agrawal, Vivek K.; Nandi, Anuj
We present an in-depth analysis and results of eleven XMM-Newton data sets, spanning 2000-2016, of the anomalous X-ray Pulsar CXOU J010043.1-721134 that has been classified as a magnetar. We find a spin period of 8.0275(1) s as of December 2016 and calculate the period derivative to be (1.76 ± 0.02) × 10-11 s s-1, which trans…
NGC 6124: a young open cluster with anomalous- and fast-rotating giant stars
Pereira, C. B.; Holanda, N.; Drake, N. A. +5 more
We present the results of a chemical analysis of fast and anomalous rotator giants members of the young open cluster NGC 6124. For this purpose, we carried out abundances of the mixing sensitive species such as Li, C, N, Na, and 12C/13C isotopic ratio, as well as other chemical species for a sample of four giants among the se…
The near-UV transit of HD 189733b with the XMM-Newton optical monitor
Wheatley, Peter J.; Louden, Tom; Steinrueck, Maria E. +6 more
We present analysis of XMM-Newton optical monitor observations in the near-ultraviolet of HD 189733, covering 20 primary transits of its hot Jupiter planet. The transit is clearly detected with both the UVW2 and UVM2 filters, and our fits to the data reveal transit depths in agreement with that observed optically. The measured depths correspond to…
A 2-d orbital period for a redback millisecond pulsar candidate in the globular cluster NGC 6397
Maccarone, Thomas J.; Heinke, Craig O.; Pichardo Marcano, Manuel +2 more
We report optical modulation of the companion to the X-ray source U18 in the globular cluster NGC 6397. U18, with combined evidence from radio and X-ray measurements, is a strong candidate as the second redback in this cluster, initially missed in pulsar searches. This object is a bright variable star with an anomalous red colour and optical varia…