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An ALMA Early Science survey of molecular absorption lines toward PKS 1830-211. Analysis of the absorption profiles
Menten, K. M.; Combes, F.; Horellou, C. +17 more
We present the first results of an ALMA spectral survey of strong absorption lines for common interstellar species in the z = 0.89 molecular absorber toward the lensed blazar PKS 1830-211. The dataset brings essential information on the structure and composition of the absorbing gas in the foreground galaxy. In particular, we find absorption over …
Magnetic reconnection, buoyancy, and flapping motions in magnetotail explosions
Merkin, V. G.; Sitnov, M. I.; Mauk, B. H. +5 more
A key process in the interaction of magnetospheres with the solar wind is the explosive release of energy stored in the magnetotail. Based on observational evidence, magnetic reconnection is widely believed to be responsible. However, the very possibility of spontaneous reconnection in collisionless magnetotail plasmas has been questioned in kinet…
Influence of physical galaxy properties on Lyα escape in star-forming galaxies
Hayes, Matthew; Schaerer, Daniel; Östlin, Göran +4 more
Context. Among the different observational techniques used to select high-redshift galaxies, the hydrogen recombination line Lyman-alpha (Lyα) is of particular interest because it gives access to the measurement of cosmological quantities such as the star formation rate (SFR) of distant galaxy populations. However, interpreting this line and calib…
An Accreting White Dwarf near the Chandrasekhar Limit in the Andromeda Galaxy
Cenko, S. Bradley; Kong, Albert K. H.; Perley, Daniel A. +13 more
The intermediate Palomar Transient Factory (iPTF) detection of the most recent outburst of the recurrent nova (RN) system RX J0045.4+4154 in the Andromeda galaxy has enabled the unprecedented study of a massive (M > 1.3 M ⊙) accreting white dwarf (WD). We detected this nova as part of the near-daily iPTF monitoring of M31 to a depth …
Compatibility of Planck and BICEP2 results in light of inflation
Ringeval, Christophe; Trotta, Roberto; Martin, Jérôme +1 more
We investigate the implications for inflation of the detection of B-modes polarization in the cosmic microwave background by BICEP2. We show that the hypothesis of the primordial origin of the measurement is favored only by the first four band powers, while the others would prefer unreasonably large values of the tensor-to-scalar ratio. Using only…
The exclusion of a significant range of ages in a massive star cluster
Deng, Licai; de Grijs, Richard; Li, Chengyuan
Stars spend most of their lifetimes on the main sequence in the Hertzsprung-Russell diagram. The extended main-sequence turn-off regions--containing stars leaving the main sequence after having spent all of the hydrogen in their cores--found in massive (more than a few tens of thousands of solar masses), intermediate-age (about one to three billio…
The Host Galaxies of Fast-ejecta Core-collapse Supernovae
Filippenko, Alexei V.; Kelly, Patrick L.; Modjaz, Maryam +1 more
Spectra of broad-lined Type Ic supernovae (SNe Ic-BL), the only kind of SN observed at the locations of long-duration gamma-ray bursts (LGRBs), exhibit wide features indicative of high ejecta velocities (~0.1c). We study the host galaxies of a sample of 245 low-redshift (z < 0.2) core-collapse SNe, including 17 SNe Ic-BL, discovered by galaxy-u…
The colour distribution of galaxies at redshift five
Ferguson, H. C.; Finkelstein, S. L.; Bowler, R. A. A. +11 more
We present the results of a study investigating the rest-frame ultraviolet (UV) spectral slopes of redshift z ≈ 5 Lyman-break galaxies (LBGs). By combining deep Hubble Space Telescope imaging of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey and Hubble Ultra-Deep Field with ground-based imaging from the UKIRT Infrared Deep Sky …
From voids to Coma: the prevalence of pre-processing in the local Universe
Gutermuth, Robert A.; Cybulski, Ryan; Yun, Min S. +1 more
We examine the effects of pre-processing across the Coma Supercluster, including 3505 galaxies over ∼500 deg2, by quantifying the degree to which star-forming (SF) activity is quenched as a function of environment. We characterize environment using the complementary techniques of Voronoi Tessellation, to measure the density field, and t…
The flux rope nature of coronal mass ejections
Vourlidas, Angelos
Coronal mass ejections (CMEs) are ejections of magnetized plasma from the solar corona. They are the most spectacular examples of explosive energy release on the Sun. Their magnetic structure is of particular importance because it determines their effects on the terrestrial magnetosphere. Here, I present recent observational evidence for the exist…