Search Publications
Ion nose spectral structures observed by the Van Allen Probes
Kistler, L. M.; Zhang, J. -C.; Spence, H. E. +5 more
We present a statistical study of nose-like structures observed in energetic hydrogen, helium, and oxygen ions near the inner edge of the plasma sheet. Nose structures are spectral features named after the characteristic shapes of energy bands or gaps in the energy-time spectrograms of in situ measured ion fluxes. Using 22 months of observations f…
Galactic survey of 44Ti sources with the IBIS telescope onboard INTEGRAL
Sunyaev, Rashid A.; Tsygankov, Sergey S.; Lutovinov, Alexander A. +4 more
We report the results of the deepest Galactic plane (|b| < 17.5°) survey in the 67.9 and 78.4 keV nuclear de-excitation lines of titanium-44 (44Ti) performed using the data acquired with the IBIS/ISGRI instrument onboard the INTEGRAL satellite during 12 yr of operation. The peak sensitivity of our survey reached an unprecedented leve…
An Investigation of the Sources of Earth-directed Solar Wind during Carrington Rotation 2053
van Driel-Gesztelyi, L.; Fazakerley, A. N.; Harra, L. K.
In this work we analyze multiple sources of solar wind through a full Carrington Rotation (CR 2053) by analyzing the solar data through spectroscopic observations of the plasma upflow regions and the in situ data of the wind itself. Following earlier authors, we link solar and in situ observations by a combination of ballistic backmapping and pote…
The Dimensionless Age of the Universe: A Riddle for Our Time
Kirshner, Robert P.; Avelino, Arturo
We present the interesting coincidence of cosmology and astrophysics that points toward a dimensionless age of the Universe H 0 t 0 that is close to one. Despite cosmic deceleration for 9 Gyr and acceleration since then, we find H 0 t 0 = 0.96 ± 0.01 for the ΛCDM model that fits SN Ia data from Pan-STARR…
Sodium Absorption Systems toward SN Ia 2014J Originate on Interstellar Scales
Foley, R. J.; Sato, B.; Tanaka, M. +21 more
Na I D absorbing systems toward Type Ia supernovae (SNe Ia) have been intensively studied over the last decade with the aim of finding circumstellar material (CSM), which is an indirect probe of the progenitor system. However, it is difficult to deconvolve CSM components from non-variable, and often dominant, components created by interstellar mat…
ROSETTA lander Philae - soil strength analysis
Arnold, Walter; Roll, Reinhard; Witte, Lars
The landing of Philae, the lander of ESA's ROSETTA-mission, on November 12th 2014 on Comet 67P/Churyumov-Gerasimenko, was planned as a descent with passive landing activating a damper system and anchoring by harpoons at touch-down. The lander was not fixed to the ground at touch-down due to failing harpoons. The lander damper, however, was actuate…
The long-wavelength thermal emission of the Pluto-Charon system from Herschel observations. Evidence for emissivity effects
Fornasier, S.; Lellouch, E.; Panuzzo, P. +9 more
Thermal observations of the Pluto-Charon system acquired by the Herschel Space Observatory in February 2012 are presented. They consist of photometric measurements with the PACS and SPIRE instruments (nine visits to the Pluto system each), covering six wavelengths from 70 to 500 µm altogether. The thermal light curve of Pluto-Charon is obser…
Improved automatic estimation of winds at the cloud top of Venus using superposition of cross-correlation surfaces
Horinouchi, Takeshi; Ikegawa, Shinichi
Accurate wind observation is a key to study atmospheric dynamics. A new automated cloud tracking method for the dayside of Venus is proposed and evaluated by using the ultraviolet images obtained by the Venus Monitoring Camera onboard the Venus Express orbiter. It uses multiple images obtained successively over a few hours. Cross-correlations are …
The Discovery of Lensed Radio and X-Ray Sources behind the Frontier Fields Cluster MACS J0717.5+3745 with the JVLA and Chandra
Churazov, E.; Zitrin, A.; Rosati, P. +24 more
We report on high-resolution JVLA and Chandra observations of the Hubble Space Telescope (HST) Frontier Cluster MACS J0717.5+3745. MACS J0717.5+3745 offers the largest contiguous magnified area of any known cluster, making it a promising target to search for lensed radio and X-ray sources. With the high-resolution 1.0-6.5 GHz JVLA imaging in A and…
INTEGRAL/IBIS deep extragalactic survey: M81, LMC and 3C 273/Coma fields
Sunyaev, Rashid A.; Lutovinov, Alexander A.; Sazonov, Sergey Yu. +3 more
We present results of a deep survey of three extragalactic fields, M81 (exposure of 9.7 Ms), Large Magellanic Cloud (6.8 Ms) and 3C 273/Coma (9.3 Ms), in the hard X-ray (17-60 keV) energy band with the IBIS telescope onboard the INTEGRAL observatory, based on 12 years of observations (2003-2015). The combined survey reaches a 4σ peak sensitivity o…