Search Publications
Direct Detection of Seasonal Changes on Triton with Hubble Space Telescope
Buratti, Bonnie J.; Bauer, James M.; Li, Jian-Yang +4 more
Triton is one of the few bodies in the solar system with observed cryo-volcanic activity, in the form of plumes at its south pole, which suggests large-scale surface volatile transport over time. Triton's large variations in obliquity have motivated prior predictions of changing atmospheric column densities of several orders of magnitude, driven b…
Characterization of Titan’s Ontario Lacus region from Cassini/VIMS observations
D'Aversa, E.; Lunine, J. I.; Coradini, A. +4 more
Liquid hydrocarbons were long predicted on Titan's surface before the RADAR instrument onboard Cassini detected lakes poleward of 70°N in July 2006. Before that the Cassini Imaging Science Subsystem (ISS) observed a lake-like feature in the South Pole, named Ontario Lacus, in July 2004. Here we analyze one observation of Ontario Lacus taken by the…
Mapping and spectroscopy of the planetary nebula NGC 7009 in the visual and infrared
Ramos-Larios, G.; Phillips, J. P.; Cuesta, L. C.
NGC 7009 is a fascinating example of a high-excitation, elliptical planetary nebula (PN) containing circumnebular rings, and FLIERs and jets along the major axis. We present visual spectroscopy along multiple position angles through the nucleus, taken with the Observatorio Astronomico Nacional (Mexico); mid-infrared (MIR) spectroscopy and imaging …
Properties of the integrated spectrum of serendipitous 2XMM catalog sources
Merloni, A.; Comastri, A.; Brusa, M. +2 more
Aims: Our analysis is aimed at characterizing the properties of the integrated spectrum of active galactic nuclei (AGNs), such as the ubiquity of the Fe Kα emission in AGNs and the dependence of the spectral parameters on the X-ray luminosity and redshift.
Methods: We selected 2646 point sources from the 2XMM catalog at high galactic lat…
Observations from Hinode/EIS of intensity oscillations above a bright point: signature of the leakage of acoustic oscillations in the inner corona
Srivastava, A. K.; Dwivedi, B. N.
We study the intensity oscillations in the upper chromosphere/transition region (TR) and corona, above a bright point (BP) in the solar atmosphere. We analyse the time series of HeII 256 Å, FeXII 195 Å and FeXV 284 Å, observed in a 40-arcsec slot close to the centre of the Sun above the BP by the extreme ultraviolet (EUV) imaging spectrometer (EIS…
Sequential Coronal Mass Ejections from AR8038 in May 1997
Liu, Y.; Luhmann, J. G.; Li, Y. +5 more
Three homologous coronal mass ejections (CMEs) occurred on 5, 12 and 16 May 1997 from the single magnetic polarity inversion line (PIL) of AR8038. The three events together provide STEREO-like quadrature views of the 12 May 1997 CME and EIT double dimming. The recurrent CMEs with the nearly identical post-CME potential state and the `sigmoid to ar…
A Detailed Study of the Rise Phase of a Long Duration X-Ray Flare in the Young Star TWA 11B
Micela, G.; Reale, F.; López-Santiago, J. +1 more
We analyzed a long duration flare observed in a serendipitous XMM-Newton detection of the M star CD-39 7717B (TWA 11B), member of the young stellar association TW Hya (~8 Myr). Only the rise phase (with a duration of ~35 ks) and possibly the flare peak were observed. We took advantage of the high count rate of the X-ray source to carry out a detai…
Gas Accretion in the M32 Nucleus: Past and Present
Seth, Anil C.
Using adaptive optics assisted Gemini/NIFS data, I study the present and past gas accretion in the central 3'' of the M32 nucleus. From changes in the spectral slope and CO line depths near the center, I find evidence for unresolved dust emission resulting from black hole (BH) accretion. With a luminosity of ~2 × 1038 erg s-1…
D/H ratio of Titan from Observations of the Cassini/Composite Infrared Spectrometer
Flasar, F. M.; Achterberg, R. K.; Jennings, D. E. +9 more
The Composite Infrared Spectrometer (CIRS) aboard the Cassini spacecraft, launched in 1997 October and inserted into Saturn's orbit in 2004 July for exploration of the Saturnian system, has been making observations of Titan during its close flybys. The infrared spectra of Titan observed over a wide range of latitudes cover the 10-1400 cm-1
XMM-Newton observations of unidentified INTEGRAL/IBIS sources
Bird, A. J.; Fiocchi, M.; Malizia, A. +4 more
About 30 per cent of the sources in the fourth INTEGRAL/IBIS catalogue are unidentified in that they lack an optical counterpart. To be able to classify them, X-ray observations are of crucial importance as they can place tighter constraints on the high-energy error box, which is usually of the order of a few arcminutes, and allow their broad-band…