Search Publications
Ancient groundwater flow in the Valles Marineris on Mars inferred from fault trace ridges
Treiman, Allan H.
Groundwater is a crucial reservoir in Mars's global water cycle and plays an important role in aqueous alteration of bedrock. Understanding groundwater flow is also important for assessing the possibility of past and present martian life. The Valles Marineris is a series of fault-bounded troughs and chasms stretching over 4,000km from west to east…
TeV J2032+4130: a not-so-dark accelerator?
Rodriguez, J.; Finley, J. P.; Konopelko, A. +5 more
The HEGRA γ-ray source TeV J2032+4130 is considered the prototypical `dark accelerator', since it was the first TeV source detected with no firm counterparts at lower frequencies. The Whipple collaboration observed this source in 2003-05 and the emission hotspot appears displaced about 9 arcmin to the northeast of the HEGRA position, though given …
A Low-Frequency (30 - 110 MHz) Antenna System for Observations of Polarized Radio Emission from the Solar Corona
Ramesh, R.; Kathiravan, C.; Barve, Indrajit V. +2 more
An interferometer antenna system to observe polarized radio emission from the solar corona at different frequencies in the range 30 - 110 MHz has been commissioned recently by the Indian Institute of Astrophysics at the Gauribidanur Radio Observatory (latitude 13°36'12''N and longitude 77°27'07''E), abou…
Observational evidence for return currents in solar flare loops
Benz, A. O.; Battaglia, M.
Context: The common flare scenario comprises an acceleration site in the corona and particle transport to the chromosphere. Using satellites available to date it has become possible to distinguish between the two processes of acceleration and transport, and study the particle propagation in flare loops in detail, as well as complete comparisons wi…
The Globular Cluster System of M60 (NGC 4649). I. Canada-France-Hawaii Telescope MOS Spectroscopy and Database
Rey, Soo-Chang; Lee, Myung Gyoon; Hwang, Ho Seong +7 more
We present radial velocity measurements for globular clusters in M60, a giant elliptical galaxy in the Virgo Cluster. Target globular cluster candidates were selected using Washington photometry based on deep 16' × 16' images taken at the KPNO 4 m telescope and using VI photometry derived from Hubble Space Telescope WFPC2 arc…
Diagnosis of magnetic structures and intermittency in space-plasma turbulence using the technique of surrogate data
Sahraoui, F.
Intermittency is usually identified in turbulent flows as non-Gaussian tails of the probability density functions (PDFs) of the turbulent field derivatives. Here we investigate the role of phase coherence among the Fourier modes in creating intermittency in magnetized space plasmas using the technique of surrogate data. We apply the technique to t…
First asteroseismic results from CoRoT
Auvergne, M.; Fridlund, M.; Ribas, I. +64 more
About one year after the end of the first observational run and six months after the first CoRoT data delivery, we comment the data exploitation progress for different types of stars. We consider first results to illustrate how these data of unprecedented quality shed a new light on the field of stellar seismology.
Near-infrared integral field spectroscopy of the Homunculus nebula around η Carinae using Gemini/CIRPASS
Sharp, R. G.; Damineli, A.; Groh, J. H. +2 more
This work presents the first integral field spectroscopy of the Homunculus nebula around η Carinae in the near-infrared spectral region (J band). We confirmed the presence of a hole on the polar region of each lobe, as indicated by previous near-IR long-slit spectra and mid-IR images. The holes can be described as a cylinder of height (i.e. the th…
X-Ray Tail in NGC 7619
Trinchieri, Ginevra; Fabbiano, Giuseppina; Kim, Dong-Woo +1 more
We present new observational results of NGC 7619, an elliptical galaxy with a prominent X-ray tail and a dominant member of the Pegasus group. With Chandra and XMM-Newton observations, we confirm the presence of a long X-ray tail in the southwest direction; moreover, we identify for the first time a sharp discontinuity of the X-ray surface brightn…
The physical structure of the point-symmetric and quadrupolar planetary nebula NGC 6309
Torrelles, J. M.; Miranda, L. F.; Vázquez, R. +4 more
Aims:We analyse the point-symmetric planetary nebula
Methods: We used VLA-D λ3.6-cm continuum, ground-based, and HST-archive imaging as well as long slit high-…