Search Publications
Lunar Occultations of 18 Stellar Sources from the 2.4 m Thai National Telescope
Dhillon, V. S.; Marsh, T. R.; Richichi, A. +3 more
We report further results from the program of lunar occultation (LO) observations started at the 2.4 m Thai National Telescope (TNT) in 2014. We have recorded LO events of 18 stellar sources, leading to the detection of four angular diameters and two binary stars. With two exceptions, these are first-time determinations. We could resolve angular d…
Asymmetrical response of dayside ion precipitation to a large rotation of the IMF
Berchem, J.; Richard, R. L.; Escoubet, C. P. +2 more
We have carried out global magnetohydrodynamics (MHD) simulations together with large-scale kinetic simulations to investigate the response of the dayside magnetospheric ion precipitation to a large rotation (135°) of the interplanetary magnetic field (IMF). The study uses simplified global MHD model (no dipole tilt and constant ionospheric conduc…
Combining strong lensing and dynamics in galaxy clusters: integrating MAMPOSSt within LENSTOOL. I. Application on SL2S J02140-0535
Gastaldello, F.; Jullo, E.; Biviano, A. +12 more
Context. The mass distribution in galaxy clusters and groups is an important cosmological probe. It has become clear in recent years that mass profiles are best recovered when combining complementary probes of the gravitational potential. Strong lensing (SL) is very accurate in the inner regions, but other probes are required to constrain the mass…
Solar irradiance observations with PREMOS filter radiometers on the PICARD mission: In-flight performance and data release
Egorova, T.; Schmutz, W.; Rozanov, E. +22 more
Context. The PREcision Monitoring Sensor (PREMOS) is a solar radiometer on board the French PICARD mission that was launched in June 2010 and decommissioned in April 2014.
Aims: The PREMOS radiometer obtains solar irradiance measurements in specific spectral windows in the UV, visible, and near-infrared. In this paper, the PREMOS data and cal…
Extensive X-ray variability studies of NGC 7314 using long XMM-Newton observations
Papadakis, I. E.; Vaughan, S.; Emmanoulopoulos, D. +1 more
We present a detailed X-ray variability study of the low-mass active galactic nuclei (AGN) NGC 7314 using the two newly obtained XMM-Newton observations (140 and 130 ks), together with two archival data sets of shorter duration (45 and 84 ks). The relationship between the X-ray variability characteristics and other physical source properties (such…
Peculiar lapse of periodic eclipsing event at low-mass X-ray binary GRS 1747-312 during Suzaku observation in 2009
Dotani, Tadayasu; Maeda, Yoshitomo; Mori, Hideyuki +6 more
GRS 1747-312 is a neutron star low-mass X-ray binary in the globular cluster Terzan 6, located at a distance of 9.5 kpc from the Earth. During its outbursts, periodic eclipses were known to occur. Observations for the outbursts were performed with Chandra in 2004 and Swift in 2013. XMM-Newton observed its quiescent state in 2004. In addition, when…
Wave propagation in a solar quiet region and the influence of the magnetic canopy
Tziotziou, K.; Tsiropoula, G.; Kontogiannis, I.
Aims: We seek indications or evidence of transmission/conversion of magnetoacoustic waves at the magnetic canopy, as a result of its impact on the properties of the wave field of the photosphere and chromosphere.
Methods: We use cross-wavelet analysis to measure phase differences between intensity and Doppler signal oscillations in the H…
On the Absence of EUV Emission from Comet C/2012 S1 (ISON)
Pesnell, W. Dean; Bryans, Paul
When the sungrazing comet C/2012 S1 (ISON) made its perihelion passage within two solar radii of the Sun’s surface, it was expected to be a bright emitter at extreme ultraviolet (EUV) wavelengths. However, despite solar EUV telescopes repointing to track the orbit of the comet, no emission was detected. This “null result” is interesting in its own…
X-ray nova MAXI J1828-249. Evolution of the broadband spectrum during its 2013-2014 outburst
Grebenev, S. A.; Burenin, R. A.; Krivonos, R. A. +2 more
Based on data from the SWIFT, INTEGRAL, MAXI/ISS orbital observatories, and the ground-based RTT-150 telescope, we have investigated the broadband (from the optical to the hard X-ray bands) spectrum of the X-ray nova MAXI J1828-249 and its evolution during the outburst of the source in 2013-2014. The optical and infrared emissions from the nova ar…
Formation of a solar Hα filament from orphan penumbrae
Solanki, S. K.; Lagg, A.; van Noort, M. +1 more
Aims: The formation and evolution of an Hα filament in active region (AR) 10953 is described.
Methods: Observations from the Solar Optical Telescope (SOT) aboard the Hinode satellite starting from UT 18:09 on 27th April 2007 until UT 06:08 on 1st May 2007 were analysed. 20 scans of the 6302 Å Fe I line pair recorded by SOT/SP were invert…