Search Publications
Fast X-ray transients towards the Galactic bulge with the Rossi X-ray Timing Explorer
Negueruela, I.; Swank, J. H.; Markwardt, C. B. +1 more
In X-ray binaries, rapid variability in X-ray flux of greater than an order of magnitude on time-scales of a day or less appears to be a signature of wind accretion from a supergiant companion. When the variability takes the form of rare, brief, bright outbursts with only faint emission between them, the systems are called supergiant fast X-ray tr…
Spatially Dependent Heating and Ionization in an ICME Observed by Both ACE and Ulysses
Laming, J. Martin; von Steiger, Rudolf; Rakowski, Cara E. +1 more
The 2005 January 21 interplanetary coronal mass ejection (ICME) observed by multiple spacecraft at L1 was also observed from January 21-February 4 at Ulysses (5.3 AU). Previous studies of this ICME have found evidence suggesting that the flanks of a magnetic cloud like structure associated with this ICME were observed at L1 while a more central cu…
Double mid-latitude dynamical reconnection at the magnetopause: An efficient mechanism allowing solar wind to enter the Earth's magnetosphere
Califano, F.; Pegoraro, F.; Faganello, M. +1 more
Three-dimensional simulations of the Kelvin-Helmholtz (KH) instability in a magnetic configuration reproducing typical conditions at the flank Earth's magnetosphere during northward periods show the system's ability to generate favorable conditions for magnetic reconnection to occur at mid-latitude. Once these conditions are established, magnetic …
On the Variations of Fundamental Constants and Active Galactic Nucleus Feedback in the Quasi-stellar Object Host Galaxy RXJ0911.4+0551 at z = 2.79
Menten, K. M.; Walter, F.; Henkel, C. +4 more
We report on sensitive observations of the CO(J = 7→6) and C I(3 P 2 → 3 P 1) transitions in the z = 2.79 QSO host galaxy RXJ0911.4+0551 using the IRAM Plateau de Bure interferometer. Our extremely high signal-to-noise spectra combined with the narrow CO line width of this source (FWHM = 120 km s-1<…
Spectral and timing properties of the accreting X-ray millisecond pulsar IGR J17498-2921
Stella, L.; Bozzo, E.; Kuiper, L. +5 more
Context. IGR J17498-2921 is the third X-ray transient accreting millisecond pulsar discovered by INTEGRAL. It was in outburst for about 40 days beginning on August 08, 2011.
Aims: We analyze the spectral and timing properties of the object and the characteristics of X-ray bursts to constrain the physical processes responsible for the X-ray pr…
Impact of solar EUV flux on CO Cameron band and CO2+ UV doublet emissions in the dayglow of Mars
Bhardwaj, Anil; Jain, Sonal Kumar
This study is aimed at making a calculation about the impact of the two most commonly used solar EUV flux models - SOLAR2000 (S2K) of Tobiska (2004) and EUVAC model of Richards et al. (1994) - on photoelectron fluxes, volume emission rates, ion densities and CO Cameron and CO2+ UV doublet band dayglow emissions on Mars in thr…
On the Relationship between the Coronal Magnetic Decay Index and Coronal Mass Ejection Speed
Xu, Yan; Liu, Chang; Jing, Ju +1 more
Numerical simulations suggest that kink and torus instabilities are two potential contributors to the initiation and prorogation of eruptive events. A magnetic parameter called the decay index (i.e., the coronal magnetic gradient of the overlying fields above the eruptive flux ropes) could play an important role in controlling the kinematics of er…
Interferometric CO(3-2) Observations toward the Central Region of NGC 1068
Matsushita, Satoki; Hwang, Chorng-Yuan; Espada, Daniel +2 more
We present CO(3-2) interferometric observations of the central region of the Seyfert 2 galaxy NGC 1068 using the Submillimeter Array, together with CO(1-0) data taken with the Owens Valley Radio Observatory Millimeter Array. Both the CO(3-2) and CO(1-0) emission lines are mainly distributed within ~5 arcsec of the nucleus and along the spiral arms…
NGC 5548: Lack of a Broad Fe Kα Line and Constraints on the Location of the Hard X-Ray Source
Liu, Y.; Elvis, M.; Krongold, Y. +2 more
We present an analysis of the co-added and individual 0.7-40 keV spectra from seven Suzaku observations of the Sy 1.5 galaxy NGC 5548 taken over a period of eight weeks. We conclude that the source has a moderately ionized, three-zone warm absorber, a power-law continuum, and exhibits contributions from cold, distant reflection. Relativistic refle…
Thermal infrared properties of classical and type II Cepheids. Diffraction limited 10 µm imaging with VLT/VISIR
Kervella, P.; Mérand, A.; Gallenne, A.
We present new thermal infrared (IR) photometry and spectral energy distributions (SEDs) of eight classical Cepheids (type I) and three type II Cepheids, using VISIR thermal IR photometric measurements, supplemented with literature data. We used the BURST mode of the instrument to get diffraction-limited images at 8.59, 11.25, and 11.85 µm. …