Search Publications
Constraining holographic cosmology using Planck data
Afshordi, Niayesh; Gould, Elizabeth; Skenderis, Kostas
Holographic cosmology offers a novel framework for describing the very early Universe in which cosmological predictions are expressed in terms of the observables of a three-dimensional quantum field theory (QFT). This framework includes conventional slow-roll inflation, which is described in terms of a strongly coupled QFT, but it also allows for …
Multi-wavelength Spectral Analysis of Ellerman Bombs Observed by FISS and IRIS
Cao, Wenda; Ding, M. D.; Hong, Jie
Ellerman bombs (EBs) are a kind of solar activity that is suggested to occur in the lower solar atmosphere. Recent observations using the Interface Region Imaging Spectrograph (IRIS) show connections between EBs and IRIS bombs (IBs), which imply that EBs might be heated to a much higher temperature (8 × 104 K) than previous results. Her…
Absolute-magnitude Calibration for W UMa-type Systems Based on Gaia Data
Rucinski, Slavek M.; Mateo, Nicole M.
Tycho-Gaia Astrometric Solution (TGAS) parallax data are used to determine absolute magnitudes M V for 318 W UMa-type (EW) contact binary stars. A very steep (slope ≃ -9), single-parameter ({log}P), linear calibration can be used to predict M V to about 0.1-0.3 mag over the whole range of accessible orbital period, 0.22&l…
Observational Constraints on Correlated Star Formation and Active Galactic Nuclei in Late-stage Galaxy Mergers
Zakamska, Nadia L.; Comerford, Julia M.; Barrows, R. Scott +1 more
Galaxy mergers are capable of triggering both star formation and active galactic nuclei (AGNs) and therefore may represent an important pathway in the co-evolution of galaxies and supermassive black holes (SMBHs). However, correlated enhancements of merger-induced star formation and AGN triggering may be hidden by the variable conditions and times…
Draining the Local Void
Shaya, Edward J.; Tully, R. Brent; Karachentsev, Igor D. +2 more
Two galaxies that lie deep within the Local Void provide a test of the expectation that voids expand. The modest ({M}B∼ -14) HI bearing dwarf galaxies ALFAZOAJ1952+1428 and KK246 have been imaged with Hubble Space Telescope in order to study the stellar populations and determine distances from the luminosities of stars at the tip of the…
A Nearly Naked Supermassive Black Hole
Darling, Jeremy; Petrov, L.; Condon, J. J. +1 more
During a systematic search for supermassive black holes (SMBHs) not in galactic nuclei, we identified the compact, symmetric radio source B3 1715+425 with an emission-line galaxy offset ≈ 8.5 {kpc} from the nucleus of the brightest cluster galaxy (BCG) in the redshift z = 0.1754 cluster ZwCl 8193. B3 1715+425 is too bright (brightness temperature …
Hub-filament System in IRAS 05480+2545: Young Stellar Cluster and 6.7 GHz Methanol Maser
Dewangan, L. K.; Ojha, D. K.; Baug, T.
To probe the star formation (SF) process, we present a multi-wavelength study of IRAS 05480+2545 (hereafter I05480+2545). Analysis of Herschel data reveals a massive clump (M clump ∼ 1875 {M}⊙ ; peak N(H2) ∼ 4.8 × 1022 cm-2 A V ∼ 51 mag) containing the 6.7 GHz methanol maser and I…
Cassini ISS observation of Saturn's north polar vortex and comparison to the south polar vortex
Dyudina, Ulyana A.; Ingersoll, Andrew P.; Ewald, Shawn P. +2 more
We present analyses of Saturn's north pole using high-resolution images captured in late 2012 by the Cassini spacecraft's Imaging Science Subsystem (ISS) camera. The images reveal the presence of an intense cyclonic vortex centered at the north pole. In the red and green visible continuum wavelengths, the north polar region exhibits a cyclonically…
Neptune long-lived atmospheric features in 2013-2015 from small (28-cm) to large (10-m) telescopes
Hueso, R.; Sánchez-Lavega, A.; Rojas, J. F. +32 more
Since 2013, observations of Neptune with small telescopes (28-50 cm) have resulted in several detections of long-lived bright atmospheric features that have also been observed by large telescopes such as Keck II or Hubble. The combination of both types of images allows the study of the long-term evolution of major cloud systems in the planet. In 2…
Distances of cataclysmic variables and related objects derived from Gaia Data Release 1
Ramsay, Gavin; Wheatley, Peter J.; Gänsicke, Boris T. +1 more
We consider the parallaxes of sixteen cataclysmic variables and related objects that are included in the TGAS catalogue, which is part of the Gaia first data release, and compared these with previous parallax measurements. The parallax of the dwarf nova SS Cyg is consistent with the parallax determination made using the VLBI, but with only one of …