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Brightness and Fluctuation of the Mid-Infrared Sky from AKARI Observations towards the North Ecliptic Pole
Brightness Fluctuation Mid-Infrared Sky AKARI Observations the North Ecliptic Pole
2012/2/21
We present the smoothness of the mid-infrared sky from observations by the Japanese infrared astronomical satellite AKARI. AKARI monitored the north ecliptic pole (NEP) during its cold phase with nine...
Do Fermi-LAT observations really imply very large Lorentz factors in GRB outflows ?
gamma-ray burst: general gamma-ray burst: individual: GRB 080916C radiative transfer radiation mechanisms: non-thermal
2011/10/20
Recent detections of GeV photons in a few GRBs by Fermi-LAT imply huge bulk Lorentz factors to avoid a large gamma gamma optical depth at high energy. Estimates can be as high as Gamma ~ 1000 in the m...
Blazars as Ultra-High-Energy Cosmic-Ray Sources: Implications for TeV Gamma-Ray Observations
Ultra-High-Energy Cosmic-Ray Sources Implications TeV Gamma-Ray Observations
2011/10/20
Spectral fitting of correlated multiwavelength data of BL Lac objects and Fanaroff-Riley I radio galaxies gives the mean comoving magnetic field strength B', the bulk outflow Doppler factor Gamma, and...
X-ray Observations of Radio Transients without Optical Hosts
X-ray Observations Radio Transients without Optical Hosts
2011/10/19
We present a 50 ks Chandra ACIS-I X-ray observation of the Bower et al. VLA archival field. The observations reach a limiting sensitivity of ~1E-4 counts/s, corresponding to a flux of a few times 1E-1...
TESELA: a new Virtual Observatory tool to determine blank fields for astronomical observations
Observatory determine blank fields astronomical observations
2011/10/12
The observation of blank fields, regions of the sky devoid of stars down to a given threshold magnitude, constitutes one of the typical important calibration procedures required for the proper reducti...
RXTE Observations of the Low-Mass X-Ray Binary 4U 1608-522 in Upper-Banana State
RXTE Observations Low-Mass X-Ray Binary 4U 1608-522 Upper-Banana State
2011/10/11
To investigate the physics of mass accretion onto weakly-magnetized neutron stars, 95 archival RXTE datasets of an atoll source 4U 1608-522, acquired over 1996-2004 in so-called upper-banana state, we...
MEM and CLEAN Imaging of VLBA Polarisation Observations of Compact Active Galactic Nuclei
CLEAN Imaging VLBA Polarisation Compact Active Galactic Nuclei
2011/10/10
The Maximum Entropy Method (MEM) for the deconvolution of radio interferometry images is mathematically well based and presents a number of advantages over the usual CLEAN deconvolution, such as appre...
Quasi periodic oscillations of solar active regions in connection with their flare activity - NoRH observations
Oscillations, Solar Radio Emission Radio Bursts, Association with Flares
2011/9/29
The sunspot-associated sources at the frequency of 17 GHz give information on plasma parameters in the regions of magnetic field about B=2000 G at the level of the chromosphere-corona transition regio...
Chemical abundances in the protoplanetary disk LV2 (Orion) - II: High dispersion VLT observations and microjet properties
ISM – abundances HII regions ISM:stars: pre-main-sequence protostars protoplan- etary disks
2011/9/29
Integral field spectroscopy of the LV2 proplyd is presented taken with the VLT/FLAMES Argus array at an angular resolution of 0.31x0.31 arcsec^2 and velocity resolutions down to 2 km/s per pixel. Foll...
Multi-Wavelength Observations of a Flux Rope Failed in the Eruption and Associated M-Class Flare from NOAA AR 11045
coronal loops magnetic eld ux rope magnetic reconnection
2011/9/27
We present the multi-wavelength observations of a flux rope that was trying to erupt from NOAA AR 11045 and the associated M-class solar flare on 12 February 2010 using space and ground based observat...
Unveiling the nature of IGR J17177-3656 with X-ray, NIR and Radio observations
accretion accretion disks – X-rays binaries – binaries
2011/8/24
We report on the first broad-band (1-200 keV) simultaneous Chandra-INTEGRAL observations of the recently discovered hard X-ray transient IGR J17177-3656 that took place on 2011, March 22, about two we...
Chandra High Energy Grating Observations of the Fe Ka Line Core in Type 2 Seyfert Galaxies: A Comparison with Type 1 Nuclei
galaxies active – line:profile – X-rays:galaxies
2011/8/24
We present a study of the core of the Fe Ka emission line at ~6.4 keV in a sample of type II Seyfert galaxies observed by the Chandra High Energy Grating (HEG). The sample consists of 29 observations ...
Chandra High Energy Grating Observations of the Fe Ka Line Core in Type 2 Seyfert Galaxies: A Comparison with Type 1 Nuclei
Grating Observations Seyfert Galaxies Comparison
2011/9/26
We present a study of the core of the Fe Ka emission line at ~6.4 keV in a sample of type II Seyfert galaxies observed by the Chandra High Energy Grating (HEG). The sample consists of 29 observations ...
XMM-Newton observations of the supergiant fast X-ray transients XTEJ1739-302, IGRJ08408-4503 and IGRJ18410-0535
XMM-Newton X-ray supergiant fast
2011/8/24
We report here on the XMM-Newton observations of the three supergiant fast X-ray transients (SFXT) XTE J1739-302, IGRJ08408-4503, and IGRJ18410-0535. For the latter source we only discuss some prelimi...
The role of the initial surface density profiles of the disc on giant planet formation: comparing with observations
the initial surface density profiles the disc on giant planet formation
2011/1/10
In order to explain the main characteristics of the observed population of extrasolar planets and the giant planets in the Solar System, we need to get a clear understanding of which are the initial c...