Search Publications

Carbon and Oxygen Abundances in Low Metallicity Dwarf Galaxies
DOI: 10.3847/0004-637X/827/2/126 Bibcode: 2016ApJ...827..126B

Skillman, Evan D.; Erb, Dawn K.; Berg, Danielle A. +2 more

The study of carbon and oxygen abundances yields information on the time evolution and nucleosynthetic origins of these elements, yet they remain relatively unexplored. At low metallicities, (12+log(O/H) < 8.0), nebular carbon measurements are limited to rest-frame UV collisionally excited emission lines. Therefore, we present the UV spectropho…

2016 The Astrophysical Journal
eHST 167
No Thermal Inversion and a Solar Water Abundance for the Hot Jupiter HD 209458b from HST/WFC3 Spectroscopy
DOI: 10.3847/0004-6256/152/6/203 Bibcode: 2016AJ....152..203L

Madhusudhan, Nikku; Fortney, Jonathan J.; Stevenson, Kevin B. +6 more

The nature of the thermal structure of hot Jupiter atmospheres is one of the key questions raised by the characterization of transiting exoplanets over the past decade. There have been claims that many hot Jupiters exhibit atmospheric thermal inversions. However, these claims have been based on broadband photometry rather than the unambiguous iden…

2016 The Astronomical Journal
eHST 166
The Shape of the Inner Milky Way Halo from Observations of the Pal 5 and GD--1 Stellar Streams
DOI: 10.3847/1538-4357/833/1/31 Bibcode: 2016ApJ...833...31B

Bovy, Jo; Kallivayalil, Nitya; Fritz, Tobias K. +1 more

We constrain the shape of the Milky Way’s halo by dynamical modeling of the observed phase-space tracks of the Pal 5 and GD-1 tidal streams. We find that the only information about the potential gleaned from the tracks of these streams are precise measurements of the shape of the gravitational potential—the ratio of vertical to radial acceleration…

2016 The Astrophysical Journal
Gaia 164
Mass Measurements in Protoplanetary Disks from Hydrogen Deuteride
DOI: 10.3847/0004-637X/831/2/167 Bibcode: 2016ApJ...831..167M

Henning, Th.; van Dishoeck, E. F.; Pontoppidan, K. M. +8 more

The total gas mass of a protoplanetary disk is a fundamental, but poorly determined, quantity. A new technique has been demonstrated to assess directly the bulk molecular gas reservoir of molecular hydrogen using the HD J = 1-0 line at 112 µm. In this work we present a Herschel Space Observatory 10 survey of six additional T Tauri…

2016 The Astrophysical Journal
AKARI Herschel 162
Planck intermediate results. XXXII. The relative orientation between the magnetic field and structures traced by interstellar dust
DOI: 10.1051/0004-6361/201425044 Bibcode: 2016A&A...586A.135P

Kneissl, R.; Miville-Deschênes, M. -A.; Boulanger, F. +201 more

The role of the magnetic field in the formation of the filamentary structures observed in the interstellar medium (ISM) is a debated topic owing to the paucity of relevant observations needed to test existing models. The Planck all-sky maps of linearly polarized emission from dust at 353 GHz provide the required combination of imaging and statisti…

2016 Astronomy and Astrophysics
Planck 162
Masses and scaling relations for nuclear star clusters, and their co-existence with central black holes
DOI: 10.1093/mnras/stw093 Bibcode: 2016MNRAS.457.2122G

Lützgendorf, Nora; Böker, Torsten; Neumayer, Nadine +2 more

Galactic nuclei typically host either a Nuclear Star Cluster (NSC, prevalent in galaxies with masses $\lesssim 10^{10}M_\odot$) or a Massive Black Hole (MBH, common in galaxies with masses $\gtrsim 10^{12}M_\odot$). In the intermediate mass range, some nuclei host both a NSC and a MBH. In this paper, we explore scaling relations between NSC mass (…

2016 Monthly Notices of the Royal Astronomical Society
eHST 162
Reconciling CMB and structure growth measurements with dark energy interactions
DOI: 10.1103/PhysRevD.94.043518 Bibcode: 2016PhRvD..94d3518P

Pourtsidou, Alkistis; Tram, Thomas

We study a coupled quintessence model with pure momentum exchange and present the effects of such an interaction on the cosmic microwave background (CMB) and matter power spectrum. For a wide range of negative values of the coupling parameter β structure growth is suppressed and the model can reconcile the tension between cosmic microwave backgrou…

2016 Physical Review D
Planck 160
Galaxy And Mass Assembly (GAMA): Panchromatic Data Release (far-UV-far-IR) and the low-z energy budget
DOI: 10.1093/mnras/stv2505 Bibcode: 2016MNRAS.455.3911D

Holwerda, Benne W.; Wilkins, Stephen M.; Conselice, Christopher J. +63 more

We present the Galaxy And Mass Assembly (GAMA) Panchromatic Data Release (PDR) constituting over 230 deg2 of imaging with photometry in 21 bands extending from the far-UV to the far-IR. These data complement our spectroscopic campaign of over 300k galaxies, and are compiled from observations with a variety of facilities including: GALax…

2016 Monthly Notices of the Royal Astronomical Society
Herschel 159
Evidence for dark matter interactions in cosmological precision data?
DOI: 10.1088/1475-7516/2016/02/037 Bibcode: 2016JCAP...02..037L

Lesgourgues, Julien; Marques-Tavares, Gustavo; Schmaltz, Martin

We study a two-parameter extension of the cosmological standard model ΛCDM in which cold dark matter interacts with a new form of dark radiation. The two parameters correspond to the energy density in the dark radiation fluid ΔNfluid and the interaction strength between dark matter and dark radiation. The interactions give rise to a ver…

2016 Journal of Cosmology and Astroparticle Physics
Planck 158
A quasi-periodic modulation of the iron line centroid energy in the black hole binary H1743-322
DOI: 10.1093/mnras/stw1245 Bibcode: 2016MNRAS.461.1967I

Ingram, Adam; Done, Chris; Middleton, Matthew +5 more

Accreting stellar-mass black holes often show a `Type-C' quasi-periodic oscillation (QPO) in their X-ray flux and an iron emission line in their X-ray spectrum. The iron line is generated through continuum photons reflecting off the accretion disc, and its shape is distorted by relativistic motion of the orbiting plasma and the gravitational pull …

2016 Monthly Notices of the Royal Astronomical Society
XMM-Newton 158