1604.00005
The distortion of the cosmic microwave background spectrum due to intergalactic dust
Imara, Loeb
IR emission from intergalactic dust might compromise the ability of future experiments to detect subtle spectral distortions in the CMB from the early Universe. Provide the first estimate of foreground contamination of the CMB signal due to diffuse dust emission in the IGM. Use models of the extragalactic background light to calculate they intensity of IGM dust emission and find that emission by IGM dust at z<0.5 exceeds the sensitivity of planned Primordial Inflation Explorer (PIXIE) to CMB spectral distortions by 1-3 orders of magnitudes. Place an upper limit on 0.23% on the contribution to the far-IR background from IGM dust emission.
1604.00006
Dynamical ejections of massive stars from your star clusters under diverse initial conditions
Oh, Kroupa
Study the effects of initial conditions (ICs) of star clusters and their massive star population on dynamical ejections of stars from star clusters up to an age of 3 Myr, particularly focusing on massive systems, using a large set of direct N-body calculations for moderately massive star clusters (Mecl=1e3.5 Msun). Vary the ICs of the calculations such as the initial half-mass radius of the clusters, initial binary populations for massive stars and initial mass segregation. Find that the initial density is the most influential parameter for the ejection fraction of the massive systems. The clusters with an initial half-mass radius of 0.1 (0.3) pc can eject put to 50% (30%) of their O-star systems on average. Most of the models show that the average ejection fraction decreases with decreasing stellar mass. For clusters efficient at ejecting O stars, the mass function of the ejected stars is top-heavy compared to the given IMF, while the mass function of stars remaining in the cluster becomes slightly steeper (top-light) than the IMF. The top-light mass functions of stars in 3Myr old clusters in the N-body models are in good agreement with the mean mass function of young intermediate mass clusters in M31 as found by Weisz et al. Show that the multiplicity fraction of the ejected massive stars can be as high as 60%, that massive high-order multiple systems can be dynamically ejected, and that high-order multiples become common especially in the cluster. Furthermore, binary populations of the ejected massive systems are discussed. When a large survey of the kinematics of the field massive stars becomes available, e.g. through Gaia, the results may be used to constan the birth configuration of massive stars in star clusters.
1604.00034
The role of quenching time in the evolution of the mass-size relation of passive galaxies from the WISP survey
Zanella, et al
Do not find a significant trend in the distributions of the difference between the observed radius and the one predicted by the mass-size relation. The relation between the galaxy age and its distance from the mass-size relation, if it exists, is rather shallow, wit ha slope alpha >~=-.6. At face value, this finding suggests that multiple dry and/or wet minor mergers, rather than the appearance of newly quenched galaxies, are mainly responsible for the observed time evolution of the mass-size relation in passive galaxies.
1604.00271
Synergies between SALT and Herschel, Euclid & the SKA: strong gravitational lensing & galaxy evolution
Serjeant
GL has seen a surge of interest n the past few years. The handful of SL systems known in the year 2000 has now been replaced with hundreds, thanks to innovative multi-wavelength selection, and there is an imminent prospect of thousands of lenses from Herschel and other sub-millimeter surveys. Euclid and SKA promise tens or even hundreds of thousands. GL is one of the very few probes capable of mapping DM halo distributions. Lensing also provides independent cosmo parameter estimates and enables the study of galaxy populations that are otherwise too faint for detained study. SALT is extremely well placed to have an enormous impact with follow-up observations of FG lenses and BG sources from e.g. Herschel, the SPT, ACT, Euclid and SKA. This paper reviews the prospects for high-impact SALT science and the many constraints of galaxy evolution want can result.
1604.00282
Strong gravitational lenses and multi-wavelength galaxy surveys with AKARI, Herschel, SPICA and Euclid
Serjeant
Submillimetre and millimeter-wave surveys with Herschel and SPT have revolutionized the discovery of SL systems. Their follow-ups have been greatly facilitated by the multi-wavelength supplementary data in the survey fields. The forthcoming Euclid optical/near-IR space telescope will also detected SL systems in large numbers, and orbital constraints are likely to require placing its deep survey at the North Ecliptic Pole (the natural deep field for a wide class of ground-based and space-based observations including AKARI, JWST and SPICA). In this paper, review the current status of the multi-wavelength survey coverage in the NEP, and discuss the prospects for the detection of SL in forthcoming or proposed facilities such as Euclid, FIRSPEX and SPICA.
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