Search Publications
STIS optical spectroscopy of the lobes of CRL 618
Velázquez, P. F.; Raga, A. C.; Riera, A. +2 more
Context. Many proto-planetary nebulae show collimated structures sometimes showing multiple outflows.
Aims: We present the results of new optical spectroscopic observations (both medium (with a dispersion of 0.56 Å pixel-1) and low (2.73 and 4.92 Å pixel-1 for the G430L and G750L gratings) spectral resolution) of the lob…
Stellar properties of z ~ 1 Lyman-break galaxies from ACS slitless grism spectra
Walsh, J. R.; Rosati, P.; Kümmel, M. +5 more
Lyman-break galaxies are now regularly found in the high redshift Universe by searching for the break in the galaxy spectrum caused by the Lyman-limit redshifted into the optical or even near-IR. At lower redshift, this break is covered by the GALEX UV channels and small samples of z ~ 1 LBGs have been presented in the literature. Here we give res…
Shock-driven variation in ionospheric outflow during the 11 October 2001 moderate storm
Dandouras, I.; Klecker, B.; Kistler, L. M. +4 more
The Composition and Distribution Function (CODIF) Analyzer on board the Cluster spacecraft frequently observes narrow-energy, field-aligned O+ ions over the polar caps and in the lobes, particularly during storm times. This population is due to ion outflow from the cusp. During the 11 October 2001 moderate storm, CODIF, located in the s…
Velocity profile of interplanetary coronal mass ejections beyond 1 AU
Lara, A.; Flandes, A.; Borgazzi, A. +1 more
We analyze the dynamics of interplanetary coronal mass ejections (ICMEs) through the interplanetary medium from the lower solar corona to ∼5.3 AU. Our analysis uses a one-dimensional hydrodynamical model derived from the fluid equation of motion that considers an effective drag force under both the laminar and turbulent hypotheses (low and high Re…
Observational Signatures of Impulsively Heated Coronal Loops: Power-Law Distribution of Energies
Erdélyi, R.; Bradshaw, S. J.; Taroyan, Y.
It has been established that small scale heating events, known as nanoflares, are important for solar coronal heating if the power-law distribution of their energies has a slope α steeper than −2 (α<−2). Forward modeling of impulsively heated coronal loops with a set of prescribed power-law indices α is performed. The power-law distribution is …
Optical variability of the ultraluminous X-ray source NGC 1313 X-2
Falomo, R.; Soria, R.; Zampieri, L. +2 more
We analyzed the longest phase-connected photometric dataset available for NGC 1313 X-2, looking for the ∼6 day modulation reported by Liu et al. (2009). The folded B-band light curve shows a 6 days periodicity with a significance slightly larger than 3σ. The low statistical significance of this modulation, along with the lack of detection in the V…
Pre-main-sequence Stellar Populations across Shapley Constellation III. I. Photometric Analysis and Identification
Henning, Thomas; Da Rio, Nicola; Gouliermis, Dimitrios A. +11 more
We present our investigation of pre-main-sequence (PMS) stellar populations in the Large Magellanic Cloud (LMC) from imaging with Hubble Space Telescope Wide-Field Planetary Camera 2. Our targets of interest are four star-forming regions located at the periphery of the super-giant shell LMC 4 (Shapley Constellation III). The PMS stellar content of…
Reinstating the M31 X-Ray System RX J0042.3+4115 as a Black Hole X-Ray Binary and Compelling Evidence for an Extended Corona
Murray, S. S.; Garcia, M. R.; Barnard, R.
The M31 X-ray source RX J0042.3+4115 was originally identified as a black hole (BH) binary because it displayed characteristic low-state variability at conspicuously high luminosities; unfortunately, this variability was later found to be artificial. However, analysis of 84 Chandra ACIS observations, a Hubble Space Telescope Advanced Camera for Su…
Lower hybrid resonances stimulated by the four CLUSTER relaxation sounders deep inside the plasmasphere: observations and inferred plasma characteristics
Lointier, G.; Rauch, J. -L.; Trotignon, J. -G. +6 more
The frequency range of the WHISPER relaxation sounder instrument on board CLUSTER, 4-80 kHz, has been chosen so as to encompass the electron gyro-frequency, Fce, and the electron plasma frequency, Fp, in most regions to be explored. Measurement of those frequencies, which are triggered as resonances by the sounder, provides a…
Two Types of Extreme-ultraviolet Brightenings In AR 10926 Observed by Hinode/EIS
Moon, Y. -J.; Choe, G. S.; Kim, Sujin +3 more
We have investigated seven extreme-ultraviolet (EUV) brightenings in the active region AR 10926 on 2006 December 2 observed by the EUV Imaging Spectrometer on board the Hinode spacecraft. We have determined their Doppler velocities and non-thermal velocities from 15 EUV spectral lines (log T = 4.7 - 6.4) by fitting each line profile to a Gaussian …