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A potential φ Per-type (Be+sdO) binary: FY CMa

Stahl, O.; Rivinius, Th.; Štefl, S. +2 more

The spectrum of the Be star FY CMa is shown to vary periodically with P=37.26±0.03 d. The types of variation, exhibiting transient strong shell phases and a radial-velocity variable He I emission component, suggest the star to be of the same type as φ Per, i.e. having an evolved hot companion ionizing the outer parts of the primary's circumstellar…

X-Rays from the Mira AB Binary System

Soker, Noam; Kastner, Joel H.

We present the results of XMM-Newton X-ray observations of the Mira AB binary system, which consists of a pulsating, asymptotic giant branch primary and nearby (~0.6" separation) secondary of uncertain nature. The European Photon Imaging Camera (EPIC) CCD (MOS and pn) X-ray spectra of Mira AB are relatively soft, peaking at ~1 keV, with only very …

Stagnated Outflow of O⁺⁵ Ions in the Source Region of the Slow Solar Wind at Solar Minimum

Chen, Y.; Strachan, L.; Hu, Y. +1 more

Using recent coordinated UVCS and LASCO measurements by Strachan and coworkers to constrain the heating parameters of a one-dimensional single-fluid minor ion model, we calculate the outflow velocity profile of O⁺⁵ ions in the flow tube overlying the helmet streamer, which has been supposed to be the source region of the slow solar wind…

A First XMM-Newton Look at the Relativistic Double Pulsar PSR J0737-3039

Bignami, G. F.; Tiengo, A.; Mereghetti, S. +5 more

We present the results of a 50 ks long X-ray observation of the relativistic double pulsar system PSR J0737-3039 obtained with the XMM-Newton satellite in 2004 March. The source has a soft spectrum (with a power-law photon index of 3.5^+0.5_-0.3 ) and a 0.2-10 keV luminosity of ~3×10³⁰ ergs s^-1 (assuming a…

The energetic NeUtral Atom Detector Unit (NUADU) for China's Double Star Mission and its calibration

Barabash, Stas; McKenna-Lawlor, Susan; Shen, Chao +11 more

An account is provided of an advanced Energetic NeUtral Atom Detector Unit (NUADU) designed for China's Double Star Mission. Special emphasis is given to describing the detector head of the instrument and its calibration.

J320 (PN G190.3-17.7) as a poly-polar planetary nebula surrounded by point-symmetric knots

López, J. A.; Meaburn, J.; Holloway, A. J. +2 more

Spatially resolved, long-slit spectra obtained with the Manchester echelle spectrometer of the planetary nebula J320 have been compared with Hubble Space Telescope and ground-based images. The morphology and kinematics of the nebular core have been convincingly modelled using the XSHAPE code.

Two and possibly three bipolar lobes, expanding at…

RR Lyrae Stars in M32: Signatures of an Ancient Population

Mateo, Mario; Alonso-García, Javier; Worthey, Guy

We report the discovery of variable stars in the dwarf elliptical galaxy M32 using a series of images obtained with the Wide Field Planetary Camera 2 on the Hubble Space Telescope. The colors, luminosities, and approximate periods of the majority of these stars indicate that they are RR Lyrae stars. Comparisons with the number of such stars identi…

Visible and infrared spectroscopy of minerals and mixtures with the OMEGA/MARS-EXPRESS instrument

Gendrin, Aline; Bibring, Jean-Pierre; Langevin, Yves +4 more

We present the reflectance measurements made with OMEGA during ground calibration on a selection of minerals and mixtures considered as candidates for constituents of the Mars surface. OMEGA is the visible and infrared mapping spectrometer designed to fly on-board the ESA/MARS-EXPRESS probe. These measurements allow to evaluate the instrument perf…

First detection of cold dust in the northern shell of NGC 5128 (Centaurus A)

Schiminovich, D.; Carilli, C. L.; van der Hulst, J. M. +2 more

Deep far-infrared (FIR) imaging data obtained with ISOPHOT at 90 µm, 150 µm, and 200 µm detected the thermal emission from cold dust in the northern shell region of NGC 5128 (Centaurus A), where previously neutral hydrogen and molecular gas has been found. A somewhat extended FIR emission region is present in both the 150 µ…

Variable Stars in the Archival HST Data of Globular Clusters M13, M30 and NGC 6712

Pietrukowicz, P.; Kaluzny, J.

We have analyzed archival HST/WFPC2 time-series data of the central parts of globular clusters M13, M30 and NGC 6712 in search for variable objects. Among a total of 21 identified variables there are 15 new discoveries. The sample includes nine RR Lyr stars, two SX Phe stars and seven W UMa-type contact binaries. One object is preliminarily classi…