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HII Region Metallicity Constraints Near the Site of the Strongly Lensed Supernova "SN Refsdal" at Redshift 1.49
(2015-04-27)
We present the local HII region metallicity near the site of the recently discovered multiply lensed supernova (SN; "SN Refsdal") at redshift 1.49. "SN Refsdal" is located at the outer spiral arm ($\sim$7 kpc) of the lensed ...
Subclasses of Type Ia Supernovae as the origin of [α/Fe] ratios in dwarf spheroidal galaxies
(2015-04-23)
Recent extensive observations of Type Ia Supernovae (SNe Ia) have revealed the existence of a diversity of SNe Ia, including SNe Iax. We introduce two possible channels in the single degenerate scenario: 1) double detonations ...
Galaxy Zoo: evidence for Diverse Star Formation Histories through the Green Valley
(2015-04-17)
Does galaxy evolution proceed through the green valley via multiple pathways or as a single population? Motivated by recent results highlighting radically different evolutionary pathways between early- and late-type galaxies, ...
Submm-bright X-ray absorbed QSOs at z~2 : insights into the co-evolution of AGN and star-formation
(2015-03-21)
We have assembled a sample of 5 X-ray-absorbed and submm-luminous type 1 QSOs at $z \sim 2$ which are simultaneously growing their central black holes through accretion and forming stars copiously. We present here the ...
First detection of the field star overdensity in the Perseus arm
(2015-03-20)
Aims. The main goal of this study is to detect the stellar overdensity associated with the Perseus arm in the anticenter direction. Methods. We used the physical parameters derived from Str\"omgren photometric data to ...
Galaxy Zoo : the dependence of the star formation-stellar mass relation on spiral disk morphology
(2015-03-19)
We measure the stellar mass-star formation rate relation in star-forming disk galaxies at z1. Of the galaxies lying significantly above the M-SFR relation in the local Universe, more than 50% are mergers. We interpret this ...
Serendipitous discovery of a dying Giant Radio Galaxy associated with NGC 1534, using the Murchison Widefield Array
(2015-03-01)
Recent observations with the Murchison Widefield Array at 185~MHz have serendipitously unveiled a heretofore unknown giant and relatively nearby ($z = 0.0178$) radio galaxy associated with NGC\,1534. The diffuse emission ...
The cluster environments of radio-loud AGN
(Cambridge University Press, 2015)
Radio-loud AGN play an important role in galaxy evolution. We need to understand their properties, and the processes that affect their behaviour in order to model galaxy formation and development. We here present preliminary ...
Tomography of Galactic star-forming regions and spiral arms with the Square Kilometer Array
(Proceedings of Science (PoS), 2014-12-19)
Very Long Baseline Interferometry (VLBI) at radio wavelengths can provide astrometry accurate to 10 micro-arcseconds or better (i.e. better than the target GAIA accuracy) without being limited by dust obscuration. This ...
The first Murchison Widefield Array low frequency radio observations of cluster scale non-thermal emission : the case of Abell 3667
(2014-11-21)
We present the first Murchison Widefield Array observations of the well-known cluster of galaxies Abell 3667 (A3667) between 105 and 241 MHz. A3667 is one of the best known examples of a galaxy cluster hosting a double ...