Search Publications
On the nature of the extragalactic number counts in the K-band
Pelló, R.; Pérez-González, P. G.; Guzmán, R. +10 more
Context: The galaxy number counts has been traditionally used to test models of galaxy evolution. However, the origin of significant differences in the shape of number counts at different wavelengths is still unclear. By relating the most remarkable features in the number counts with the underlying galaxy population it is possible to introduce fur…
The Two Integral X-Ray Transients IGR J17091-3624 and IGR J17098-3628: A Multiwavelength Long-Term Campaign
Hill, A. B.; Giroletti, M.; Capitanio, F. +7 more
IGR J17091-3624 and IGR J17098-3628 are two X-ray transients discovered by INTEGRAL and classified as possible black hole candidates. We present here the results obtained from the analysis of multiwavelength data sets collected by different instruments from 2005 until the end of 2007 on both sources. IGR J17098-3628 has been regularly detected by …
Suzaku X-Ray Study of an Anomalous Source XSS J12270-4859
Ishida, Manabu; Tsujimoto, Masahiro; Ebisawa, Ken +1 more
We report on the results of a Suzaku X-ray observation of XSSJ12270-4859, one of the hard X-ray sources in the INTEGRAL catalogue. This object has been classified as an intermediate polar (IP) by its optical spectra, and a putative X-ray period of ∼860s. With a 30ks exposure by Suzaku, we obtained a well-exposed spectrum in the 0.2--70keV band. We…
Mass Distribution in the Central Few Parsecs of Our Galaxy
Figer, Donald F.; Oh, Seung-Kyung; Kim, Sung-Soo S.
We estimate the enclosed mass profile in the central 10 pc of the Milky Way by analyzing the infrared photometry and the velocity observations of dynamically relaxed stellar population in the Galactic center. HST/NICMOS and Gemini Adaptive Optics images in the archive are used to obtain the number density profile, and proper motion and radial velo…
Identification of photoelectron energy peaks in Saturn's inner neutral torus
Schippers, P.; André, N.; Coates, A. J. +5 more
We present observations from the Cassini Plasma Electron Spectrometer (CAPS/ELS) of characteristic peaks in the electron energy spectrum that are identified in the innermost regions of the Saturnian magnetosphere during low-latitude orbits of the Cassini spacecraft around Saturn. We show how a narrow electron energy peak at about 20 eV and a possi…
An XMM-Newton Spectral and Timing Study of IGR J16207 - 5129: An Obscured and Non-Pulsating HMXB
Kaaret, Philip; Walter, Roland; Tomsick, John A. +3 more
We report on a ~12 hr XMM-Newton observation of the supergiant high-mass X-ray binary (HMXB) IGR J16207 - 5129. This is only the second soft X-ray (0.4-15 keV, in this case) study of the source since it was discovered by the International Gamma-Ray Astrophysics Laboratory satellite. The average energy spectrum is very similar to those of neutron s…
Small Carbonaceous Molecules, Ethylene Oxide (c-C2H4O) and Cyclopropenylidene (c-C3H2): Sources of the Unidentified Infrared Bands?
Bernstein, Lawrence S.; Lynch, David K.
We suggest that small carbonaceous molecules (SCMs) may be the sources of the unidentified infrared bands (UIRs) and the underlying continuum. We show that the IR spectroscopy of ethylene oxide (EO, c-C2H4O) and cyclopropenylidene (CP, c-C3H2) closely correlates with the major UIR bands at 3.3, 6.2, 7.7,…
The present-day atmosphere of Mars: Where does it come from?
Chassefière, Eric; Gillmann, Cédric; Lognonné, Philippe +1 more
Recent observations and missions to Mars have provided us with new insight into the past habitability of Mars and its history. At the same time they have raised many questions on the planet evolution. We show that even with the few data available we can propose a scenario for the evolution of the Martian atmosphere in the last three billion years.…
Near-IR search for lensed supernovae behind galaxy clusters. I. Observations and transient detection efficiency
Lidman, C.; Amanullah, R.; Goobar, A. +11 more
Context: Massive galaxy clusters at intermediate redshift can magnify the flux of distant background sources by several magnitudes.
Aims: We exploit this effect to search for lensed distant supernovae that may otherwise be too faint to be detected.
Methods: A supernova search was conducted at near infrared wavelengths using the ISAAC instr…
Evaluation of magnetic helicity density in the wave number domain using multi-point measurements in space
Glassmeier, K. -H.; Narita, Y.; Kleindienst, G.
We develop an estimator for the magnetic helicity density, a measure of the spiral geometry of magnetic field lines, in the wave number domain as a wave diagnostic tool based on multi-point measurements in space. The estimator is numerically tested with a synthetic data set and then applied to an observation of magnetic field fluctuations in the E…