Search Publications
The FERRUM project: Experimental lifetimes and transition probabilities from highly excited even 4d levels in Fe ii
Nilsson, H.; Lundberg, H.; Hartman, H. +1 more
We report lifetime measurements of the 6 levels in the 3d6(5D)4d e6G term in Fe ii at an energy of 10.4 eV, and f-values for 14 transitions from the investigated levels. The lifetimes were measured using time-resolved laser-induced fluorescence on ions in a laser-produced plasma. The high excitation energy, and the…
Characteristics of four SPE groups with different origins and acceleration processes
Cho, K. -S.; Kim, R. -S.; Park, Y. -D. +3 more
Solar proton events (SPEs) can be categorized into four groups based on their associations with flare or CME inferred from onset timings as well as acceleration patterns using multienergy observations. In this study, we have investigated whether there are any typical characteristics of associated events and acceleration sites in each group using 4…
On the black hole masses in ultra-luminous X-ray sources
Zhou, Xin-Lin
Ultra-luminous X-ray sources (ULXs) are off-nuclear X-ray sources in nearby galaxies with X-ray luminosities ⩾ 1039 erg s-1. The measurement of the black hole (BH) masses of ULXs is a long-standing problem. Here we estimate BH masses in a sample of ULXs with XMM-Newton observations using two different mass indicators, the X-r…
Ponding, draining and tilting of the Cerberus Plains; a cryolacustrine origin for the sinuous ridge and channel networks in Rahway Vallis, Mars
Balme, M. R.; Conway, S. J.; Gallagher, C. +1 more
Rahway Vallis sits within a shallow basin (the "Rahway basin") in the Cerberus Plains of Mars containing a branching network of channels converging on the basin floor. Using topographic cross-profiles of the channels we have found that they are set within broader, subtly-expressed, valleys. These valleys are shallow (around 15 m vertically compare…
Differential measurement of atmospheric refraction using a telescope with double fields of view
Zhao, Ming; Yu, Yong; Cao, Jian-Jun +2 more
For the sake of advancing theoretical research about atmospheric refraction, the atmospheric refraction observed at lower angles of elevation is still worth analyzing and exploring. In some engineering applications, objects with a larger zenith distance must sometimes be observed. Carrying out observational research on atmospheric refraction at lo…
The low energy magnetic spectrometer on Ulysses and ACE response to near relativistic protons
Filipe Maia, Dalmiro Jorge; Gonçalves, Patrícia; Morgado, Bruno +2 more
Aims: We show that the Heliosphere Instrument for Spectra Composition and Anisotropy at Low Energies (HISCALE) on board the Ulysses spacecraft and the Electron Proton Alpha Monitor (EPAM) on board the Advance Composition Explorer (ACE) spacecraft can be used to measure properties for ion populations with kinetic energies in excess of 1 GeV. T…
A Statistical Study of H I Gas in Nearby Narrow-Line AGN-Hosting Galaxies
Wu, Hong; Zhu, Yi-Nan
As a quenching mechanism, active galactic nucleus (AGN) feedback could suppress on going star formation in host galaxies. On the basis of a sample of galaxies selected from the Arecibo Legacy Fast ALFA (ALFALFA) H i survey, the dependence of the H i mass (MH i), stellar mass (M*), and H i-to-stellar mass ratio (MH i
Source-plane Reconstruction of the Giant Gravitational Arc in A2667: A Candidate Wolf-Rayet Galaxy at z ~ 1
Richard, Johan; Izzo, Luca; Jullo, Eric +3 more
We present a new analysis of Hubble Space Telescope, Spitzer Space Telescope, and Very Large Telescope imaging and spectroscopic data of a bright lensed galaxy at z = 1.0334 in the lensing cluster A2667. Using this high-resolution imaging, we present an updated lens model that allows us to fully understand the lensing geometry and reconstruct the …
Proving strong magnetic fields near to the central black hole in the quasar PG0043+039 via cyclotron lines
Schartel, N.; Rodríguez-Pascual, P. M.; Santos-Lleó, M. +3 more
Context. The optical luminous quasar PG0043+039 has not been detected before in deep X-ray observations indicating the most extreme optical-to-X-ray slope index αox of all quasars.
Aims: This study aims to detect PG0043+039 in a deep X-ray exposure. Furthermore, we wanted to check out whether this object shows specific spectral pro…
Time series with tailored nonlinearities
Räth, C.; Laut, I.
It is demonstrated how to generate time series with tailored nonlinearities by inducing well-defined constraints on the Fourier phases. Correlations between the phase information of adjacent phases and (static and dynamic) measures of nonlinearities are established and their origin is explained. By applying a set of simple constraints on the phase…