Search Publications
Infrared Spectral Energy Distribution of Galaxies in the AKARI All Sky Survey: Correlations with Galaxy Properties, and Their Physical Origin
Takeuchi, Tsutomu T.; Makiya, Ryu; Totani, Tomonori +2 more
We have studied the properties of more than 1600 low-redshift galaxies by utilizing high-quality infrared flux measurements of the AKARI All-Sky Survey and physical quantities based on optical and 21-cm observations. Our goal is to understand the physics determining the infrared spectral energy distribution (SED). The ratio of the total infrared l…
Pitch angles of distant spiral galaxies
Savchenko, S. S.; Reshetnikov, V. P.
We have studied the pitch angles of spiral arms for 31 distant galaxies at z ∼ 0.7 from three Hubble Deep Fields (HDF-N, HDF-S, HUDF). Using the pitch angle-rotation velocity relation calibrated from nearby galaxies, we have estimated the rotation velocities of galaxies from the deep fields. These estimates have a low accuracy (∼50 km s-1
An X-ray view of the INTEGRAL/IBIS blazars
de Rosa, A.; Ubertini, P.; Bassani, L. +3 more
The aim of this work is a broad-band study, using the INTEGRAL, Swift and XMM-Newton satellites, of a sample of nine blazars (seven flat-spectrum radio quasars and two BL Lacertae objects) with redshift (z) up to about 4. The spectral analysis has shown clear evidence of a flattening of the continuum towards low energies (E < 3 keV observer fra…
Thermal analysis of fractures at Cerberus Fossae, Mars: Detection of air convection in the porous debris apron
Lopez, T.; Antoine, R.; Baratoux, D. +2 more
This study investigates the cause of high nighttime temperatures within Cerberus Fossae, a system of fractures affecting the Central Elysium Planitia. The inner parts (walls and floor) of the fractures are up to 40 K warmer than the surrounding plains. However, several temperature profiles exhibit a local temperature minima occurring in the centra…
The importance of thermal electron heating in Titan's ionosphere: Comparison with Cassini T34 flyby
Coates, A. J.; Russell, C. T.; Dougherty, M. K. +9 more
We use a new magnetohydrodynamic (MHD) model to study the effects of thermal-electron heating in Titan's ionosphere. This model improves the previously used multispecies MHD model by solving both the electron and ion pressure equations instead of a single plasma pressure equation. This improvement enables a more accurate evaluation of ion and elec…
Determining Absorption, Emissivity Reduction, and Local Suppression Coefficients inside Sunspots
Zhao, Junwei; Ilonidis, Stathis
The power of solar acoustic waves is reduced inside sunspots mainly due to absorption, emissivity reduction, and local suppression. The coefficients of these power-reduction mechanisms can be determined by comparing time - distance cross-covariances obtained from sunspots and from the quiet Sun. By analyzing 47 active regions observed by SOHO/MDI …
On the Flare-induced Seismicity in the Active Region NOAA 10930 and Related Enhancement of Global Waves in the Sun
García, R. A.; Tiwari, Sanjiv Kumar; Venkatakrishnan, P. +2 more
A major flare (of class X3.4) occurred on 2006 December 13 in the active region NOAA 10930. This flare event has remained interesting to solar researchers for studies related to particle acceleration during the flare process and the reconfiguration of magnetic fields as well as fine-scale features in the active region. The energy released during f…
Discovery and identification of infrared counterpart candidates of four Galactic centre low mass X-ray binaries
Chaty, S.; Curran, P. A.; Zurita Heras, J. A.
Context. The near infrared (nIR)/optical counterparts of low mass X-ray binaries (LMXBs) are often observationally dim and reside in high source density fields which make their identification problematic; however, without such a counterpart identification we are unable to investigate many of the properties of LMXB systems.
Aims: Here, in the …
Multi-spacecraft investigation of space turbulence: Lessons from Cluster and input to the Cross-Scale mission
Belmont, Gérard; Rezeau, Laurence; Sahraoui, Fouad +9 more
Investigating space plasma turbulence from single-point measurements is known to be characterized by unavoidable ambiguities in disentangling temporal and spatial variations. Solving this problem has been one of the major goals of the Cluster mission. For that purpose multipoint measurements techniques, such as the k-filtering, have been developed…
No Confirmed New Isolated Neutron Stars in the SDSS Data Release 4
Anderson, Scott F.; Haberl, Frank; Rosenfield, Philip +6 more
We report on follow-up observations of candidate X-ray-bright, radio-quiet isolated neutron stars (INSs) identified from correlations of the ROSAT All-Sky Survey (RASS) and the Sloan Digital Sky Survey (SDSS) Data Release 4 in Agüeros et al. We obtained Chandra X-ray Observatory exposures for 13 candidates in order to pinpoint the source of X-ray …