Search Publications
Toward a Measurement of the Transverse Peculiar Velocity of Galaxy Pairs
Darling, Jeremy; Truebenbach, Alexandra E.
The transverse peculiar velocities caused by the mass distribution of large-scale structure (LSS) provide a test of the theoretical matter power spectrum and the cosmological parameters that contribute to its shape. Typically, the matter density distribution of the nearby universe is measured through redshift or line-of-sight peculiar velocity sur…
A physical process of the radial acceleration of disc galaxies
Wilhelm, Klaus; Dwivedi, Bhola N.
An impact model of gravity designed to emulate Newton's law of gravitation is applied to the radial acceleration of disc galaxies. Based on this model (Wilhelm et al. 2013), the rotation velocity curves can be understood without the need to postulate any dark matter contribution. The increased acceleration in the plane of the disc is a consequence…
PFS/MEX limb observations of 4.3-µm CO2 non-LTE emission in the atmosphere of Mars
Sindoni, G.; Formisano, V.; Longobardo, A. +3 more
We present PFS-MEX limb observations of the CO2 non-local thermodynamic equilibrium (non-LTE) emission at 4.3 µm in the atmosphere of Mars collected in more than six Martian years. With unprecedented spatial and temporal coverage, and relatively high spectral resolution, this unique dataset promises to improve our understanding of…
Spatially Resolved Sub-millimeter Continuum Imaging of Neptune with ALMA
Iino, Takahiro; Yamada, Takayoshi
This paper reports the result of spatially resolved 646 GHz sub-millimeter imaging observation of Neptune obtained by the Atacama Large Millimeter and sub-millimeter Array. The observation was performed in 2012 August as the flux calibration and synthesized beam size were small enough to resolve Neptune’s disk at this time. This analysis aims to c…
Revisiting the Iron Abundance in the Hyper Iron-poor Star HE 1327-2326 with UV COS/HST Data
Ezzeddine, Rana; Frebel, Anna
We present a new iron abundance analysis of the hyper metal-poor star HE 1327-2326, based on Fe II lines detected in its UV spectral range for the first time. In a Cosmic Origins Spectrograph (COS) spectrum, five new Fe II lines could be measured. A Si I line was also detected for the first time. We determine a 1D local thermodynamic equilibrium (…
Strong lensing constraints on modified gravity models
Dai, De-Chang; Stojkovic, Dejan; Starkman, Glenn D.
We impose the first strong-lensing constraints on a wide class of modified gravity models where an extra field that modifies gravity also couples to photons (either directly or indirectly through a coupling with baryons) and thus modifies lensing. We use the nonsingular isothermal ellipsoid profile as an effective potential which produces flat gal…
On application of asymmetric Kan-like exact equilibria to the Earth magnetotail modeling
Semenov, Vladimir S.; Erkaev, Nikolai V.; Kubyshkina, Marina V. +3 more
A specific class of solutions of the Vlasov-Maxwell equations, developed by means of generalization of the well-known Harris-Fadeev-Kan-Manankova family of exact two-dimensional equilibria, is studied. The examined model reproduces the current sheet bending and shifting in the vertical plane, arising from the Earth dipole tilting and the solar win…
A statistical analysis of two-dimensional patterns and its application to astrometry
Zavada, Petr; Píška, Karel
Here we develop a general statistical procedure for the analysis of finite two-dimensional (2D) patterns inspired by the analysis of heavy-ion data. The method is used in the study of publicly available data obtained by the Gaia-ESA mission. We prove that the procedure can be sensitive to the limits of accuracy of measurement, and can also clearly…
Chandra Observations of NuSTAR Serendipitous Sources near the Galactic Plane
Aird, James; Stern, Daniel; Rahoui, Farid +8 more
The Nuclear Spectroscopic Telescope Array (NuSTAR) serendipitous survey has already uncovered a large number of active galactic nuclei (AGNs), providing new information about the composition of the cosmic X-ray background. For AGNs off the Galactic plane, it has been possible to use existing X-ray archival data to improve source localizations, ide…
Association between Tornadoes and Instability of Hosting Prominences
Poedts, Stefaan; Shergelashvili, Bidzina M.; Mghebrishvili, Irakli +4 more
We studied the dynamics of all prominence tornadoes detected by the Solar Dynamics Observatory/Atmospheric Imaging Assembly from 2011 January 01 to December 31. In total, 361 events were identified during the whole year, but only 166 tornadoes were traced until the end of their lifetime. Out of 166 tornadoes, 80 (48%) triggered CMEs in hosting pro…