Search Publications
Morphology of galaxies in the Coma cluster region down to M_B = -14.25. I. A catalog of 473 members
Andreon, S.; Michard, R.
This paper presents morphological type, membership, and U{-}V color for a sample of galaxies in the Coma cluster direction, complete down to M_B=-15.00 mag and extending down to M_B=-14.25 mag. We have examined 1155 objects from the GMP 1983 catalog on B and V images of the CFH12K camera, and obtained the Hubble type in most cases. Coma cluster me…
NGC 300 X-1 and IC 10 X-1: a new breed of black hole binary?
Barnard, R.; Clark, J. S.; Kolb, U. C.
Context: IC 10 X-1 has recently been confirmed as a black hole (BH) + Wolf-Rayet (WR) X-ray binary, and NGC 300 X-1 is thought to be. The only other known BH+WR candidate is Cygnus X-3. IC 10 X-1 and NGC 300 X-1 have similar X-ray properties, with 0.3-10 keV luminosities ~1038 erg s-1, and their X-ray lightcurves exhibit orbi…
X-ray absorption in distant type II QSOs
Barcons, X.; Carrera, F. J.; Watson, M. G. +7 more
Aims: We present the results of the X-ray spectral analysis of an XMM-Newton-selected type II QSO sample with z ≥ 0.5 and 0.5-10 keV flux of 0.3-33×10-14 erg/s/cm^2. The distribution of absorbing column densities in type II QSOs is investigated and the dependence of absorption on X-ray luminosity and redshift is studied.
Methods: We…
A probable close brown dwarf companion to GJ 1046 (M 2.5V)
Kürster, M.; Reffert, S.; Endl, M.
Context: Brown dwarf companions to stars at separations of a few AU or less are rare objects, and none have been found so far around early-type M dwarfs (M 0V-M 5V). With GJ 1046 (M 2.5V), a strong candidate for such a system with a separation of 0.42 AU is presented.
Aims: We aim at constraining the mass of the companion in order to decide wh…
Suppression of convection around small magnetic concentrations
Ichimoto, K.; Katsukawa, Y.; Shimojo, M. +3 more
Aims: It is well known that convective motions in the photosphere are suppressed by magnetic fields. However, it has been difficult to study the interaction between convection and small magnetic features, such as G-band bright points (GBPs) or pores with polarimetric measurements, because of the available spatial resolution (~1´´). This situation …
High-redshift blazar identification for Swift J1656.3-3302
Palazzi, E.; Masetti, N.; Gehrels, N. +9 more
We report on the high-redshift blazar identification of a new gamma-ray source, Swift J1656.3-3302, detected with the BAT imager onboard the Swift satellite and the IBIS instrument on the INTEGRAL satellite. Follow-up optical spectroscopy has allowed us to identify the counterpart as an R∼ 19 mag source that shows broad Lyman-α, Si iv, He ii, C iv…
Multi-spacecraft observations of polar coronal plumes
Feng, L.; Wilhelm, K.; Curdt, W. +1 more
Aims:Coronal plumes, along with their structure and rôle in the acceleration of the fast solar wind, are of considerable importance in understanding the physics of the solar atmosphere, in particular, when contrasted with the adjacent plasma, the so-called interplume regions.
Methods: Observations of coronal plumes in a coronal hole were obtai…
The XMM-Newton survey of the ELAIS-S1 field. II. Optical identifications and multiwavelength catalogue of X-ray sources
Berta, S.; Pozzi, F.; Fiore, F. +13 more
We present the optical identifications and a multi-band catalogue of a sample of 478 X-ray sources detected in the XMM-Newton and Chandra surveys of the central 0.6 deg2 of the ELAIS-S1 field. The most likely optical/infrared counterpart of each X-ray source was identified using the chance coincidence probability in the R and IRAC 3.6 &…
A C-level flare observed in an arch filament system: reconnection between pre-existing and emerging field lines?
Romano, P.; Spadaro, D.; Contarino, L. +3 more
Context: Observations show that solar flares are often caused by the emergence of new magnetic flux from subphotospheric layers and by the interaction of the rising field lines with the ambient magnetic field. In this framework, recent theoretical models of magnetic flux emergence have investigated the effectiveness of magnetic reconnection as a f…
HE 0515-4414: an unusual sub-damped Ly α system revisited
Reimers, D.; Baade, R.; Quast, R.
Aims:We examine the ionization, abundances, and differential dust depletion of metals, the kinematic structure, and the physical conditions in the molecular hydrogen-bearing sub-damped Ly α system toward HE 0515-4414.
Methods: We used the STIS and VLT UVES spectrographs to obtain high-resolution recordings of the damped Ly α profile and numero…