Search Publications
A State Transition of the Luminous X-Ray Binary in the Low-metallicity Blue Compact Dwarf Galaxy I Zw 18
Feng, Hua; Kaaret, Philip
We present a measurement of the X-ray spectrum of the luminous X-ray binary in I Zw 18, the blue compact dwarf galaxy with the lowest known metallicity. We find the highest flux yet observed, corresponding to an intrinsic luminosity near 1 × 1040 erg s-1 establishing it as an ultraluminous X-ray source (ULX). The energy spect…
SHARDS: stellar populations and star formation histories of a mass-selected sample of 0.65 < z < 1.1 galaxies
Barro, Guillermo; Pérez-González, Pablo G.; Tresse, Laurence +10 more
We report on results from the analysis of a stellar mass-selected (log (M*/M⊙) ≥ 9.0) sample of 1644 galaxies at 0.65 < z < 1.1 with ultradeep (mAB < 26.5) optical medium-band (R ∼ 50) photometry from the Survey for High-z Absorption Red and Dead Sources (SHARDS). The spectral resolution of SHARDS allows u…
Rapid loss of the plasma sheet energetic electrons associated with the growth of whistler mode waves inside the bursty bulk flows
Cao, J. B.; Yang, J. Y.; Yu, J. +5 more
the interval ~07:45:36-07:54:24 UT on 24 August 2005, Cluster satellites (C1 and C3) observed an obvious loss of energetic electrons (~3.2-95 keV) associated with the growth of whistler mode waves inside some bursty bulk flows (BBFs) in the midtail plasma sheet (XGSM ~ -17.25 RE). However, the fluxes of the higher-energy elec…
Direct Detections of Young Stars in Nearby Elliptical Galaxies
Bregman, Joel N.; Ford, H. Alyson
Small amounts of star formation in elliptical galaxies are suggested by several results: surprisingly young ages from optical line indices, cooling X-ray gas, and mid-infrared dust emission. Such star formation has previously been difficult to directly detect, but using ultraviolet Hubble Space Telescope Wide Field Camera 3 imaging, we have identi…
Sunskirting comets discovered with the LASCO coronagraphs over the decade 1996-2008
Llebaria, A.; Lamy, P.; A'Hearn, M. F. +3 more
In addition to an unprecedented number of Kreutz sungrazing comets, the LASCO coronagraphs have discovered some 238 unrelated “sunskirting” comets over the 12 years from 1996 to 2008. This new class is organized in several groups, and at least two comets have further been found periodic. This article presents the photometry and the heliocentric li…
Multiscale Magnetic Underdense Regions on the Solar Surface: Granular and Mesogranular Scales
Giordano, S.; Berrilli, F.; Scardigli, S.
The Sun is a non-equilibrium, dissipative system subject to an energy flow that originates in its core. Convective overshooting motions create temperature and velocity structures that show a temporal and spatial multiscale evolution. As a result, photospheric structures are generally considered to be a direct manifestation of convective plasma mot…
Water Maser Survey on AKARI and IRAS Sources: A Search for "Low-velocity" Water Fountains
Kwok, Sun; Yung, Bosco H. K.; Nakashima, Jun-ichi +3 more
We present the results of a 22 GHz H2O maser survey toward a new sample of asymptotic giant branch (AGB) and post-AGB star candidates. Most of the objects are selected for the first time based on the AKARI data, which have high flux sensitivity in the mid-infrared ranges. We aim at finding H2O maser sources in the transient p…
Quasi-periodic oscillations and energy spectra from the two brightest Ultra-Luminous X-ray sources in M82
Belloni, T.; Zampieri, L.; Caballero-García, M. D.
Ultra-Luminous X-ray sources (ULXs) are thought to be accreting black holes (BHs) that might host intermediate-mass black holes (IMBH), proposed to exist by theoretical studies, even though a firm detection (as a class) is still missing. The brightest ULX in M82 (M82 X-1) is probably one of the best candidates to host an IMBH. In this work, we ana…
Deep hard X-ray survey of the Large Magellanic Cloud
Tsygankov, S. S.; Lutovinov, A. A.; Grebenev, S. A. +1 more
Results of the deep survey of the Large Magellanic Cloud (LMC) obtained with the INTEGRAL observatory are presented. The long exposure ( ∼ 7 Ms) allowed us to detect 21 sources in this sky region: ten belonging to the LMC itself (7 HMXBs, 2 PSRs, 1 LMXB), six of extragalactic origin and three belonging to other galaxies in the Local Group - the Mi…
Dependence of O+ escape rate from the Venusian upper atmosphere on IMF directions
Fedorov, A.; Barabash, S.; Futaana, Y. +5 more
investigate the dependence of the O+ escape rate on the upstream interplanetary magnetic field (IMF) direction by using data from the Analyser of Space Plasma and Energetic Atoms (ASPERA-4) instrument and the magnetometer (MAG) onboard Venus Express. We consider two cases, namely the perpendicular IMF case (167 events) and the parallel …