Science Archives Publication System

Chandra and XMM-Newton Observations of the Vela-like Pulsar B1046-58

DOI: 10.1086/507125 Bibcode: 2006ApJ...652..569G

Gaensler, B. M.; Gonzalez, M. E.; Kaspi, V. M. +1 more

We present results from Chandra and XMM-Newton observations of the radio pulsar B1046-58. A high-resolution spatial analysis reveals an asymmetric pulsar wind nebula (PWN), ~6^''×11^'' in size. The combined emission from the pulsar and its PWN is faint, with a best-fit power-law photon index of Γ=1.7^+0.4_-0.2

2006 • The Astrophysical Journal

XMM-Newton 29

Why is the mass function of NGC 6218 flat?

DOI: 10.1051/0004-6361:20053775 Bibcode: 2006A&A...449..161D

Pulone, L.; Paresce, F.; de Marchi, G.

We have used the FORS-1 camera on the VLT to study the main sequence (MS) of the globular cluster NGC 6218 in the V and R bands. The observations cover an area of 3.4 arcmin × 3.4 arcmin around the cluster centre and probe the stellar population out to the cluster's half-mass radius (r_h ≃ 2.2 arcmin). The colour-magnitude diagram (CMD) …

2006 • Astronomy and Astrophysics

Hipparcos 29

The Unusual X-Ray Spectrum of FU Orionis

DOI: 10.1086/502967 Bibcode: 2006ApJ...643..995S

Skinner, Stephen L.; Güdel, Manuel; Briggs, Kevin R.

FU Orionis objects (FUors) have undergone strong optical outbursts and are thought to be young low-mass stars accreting at high rates of up to M˙_acc~10^-4 M_solar yr^-1. FUors have been extensively studied at optical and infrared wavelengths, but little is known about their X-ray properties. We have thus in…

2006 • The Astrophysical Journal

XMM-Newton 28

Evidence of Orbital Motion in the Binary Brown Dwarf Kelu-1AB

DOI: 10.1086/502985 Bibcode: 2006PASP..118..611G

Kulkarni, S. R.; Gelino, Christopher R.; Stephens, Denise C.

We have resolved Kelu-1 into a binary system with a separation of ~290 mas using the Laser Guide Star Adaptive Optics system on the Keck II telescope. We have also reanalyzed a 1998 HST observation of Kelu-1 and find that the observed PSF is best fit by a binary object separated by 45 mas. Observations at multiple epochs confirm that the two objec…

2006 • Publications of the Astronomical Society of the Pacific

eHST 28

The sequestration of ethane on Titan in smog particles

DOI: 10.1038/nature05157 Bibcode: 2006Natur.443..669H

Hunten, D. M.

Saturn's largest satellite, Titan, has a dense atmosphere of nitrogen with a few per cent of methane. At visible wavelengths its surface is hidden by dense orange-brown smog, which is produced in the stratosphere by photochemical reactions following the dissociation of methane by solar ultraviolet light. The most abundant of the products of these …

2006 • Nature

Cassini 28

The super-soft source XMMU J052016.0-692505 in the LMC. A likely white dwarf Be/X-ray binary

DOI: 10.1051/0004-6361:20065490 Bibcode: 2006A&A...458..285K

Haberl, F.; Kahabka, P.; Filipović, M. D. +1 more

Aims.We report the discovery of the super-soft X-ray source XMMU J052016.0-692505 in the LMC with XMM-Newton.
Methods: .We analyse the EPIC spectra of XMMU J052016.0-692505 and study the likely optical counterpart LMCV2135.
Results: .Using an absorbed blackbody spectrum we derive a bolometric luminosity of ⪆ 10³⁴ erg s^-1

2006 • Astronomy and Astrophysics

XMM-Newton 28

Detecting X-ray QPOs in active galaxies

DOI: 10.1016/j.asr.2005.02.064 Bibcode: 2006AdSpR..38.1405V

Vaughan, Simon; Uttley, Philip

Since EXOSAT produced the first good quality X-ray light curves of Seyfert galaxies there have been several claims of quasi-periodic oscillations (QPOs). None of these have withstood repeated analyses and observations. We review some problems concerning the detection of QPOs.

2006 • Advances in Space Research

Exosat 28

Proper-Motion Measurements of the Cygnus Egg Nebula

DOI: 10.1086/500642 Bibcode: 2006ApJ...641.1113U

Ueta, Toshiya; Meixner, Margaret; Murakawa, Koji

We present the results of proper-motion measurements of the dust shell structure in the Egg Nebula (AFGL 2688, CRL 2688, V1610 Cyg), based on the archived two-epoch data at 2 µm taken with the Hubble Space Telescope. We measured the amount of motion of local structures in the nebula by determining their relative shifts over an interval of 5.…

2006 • The Astrophysical Journal

eHST 28

Auroral Plasma Acceleration Above Martian Magnetic Anomalies

DOI: 10.1007/s11214-006-9086-x Bibcode: 2006SSRv..126..333L

Coates, A. J.; Kallio, E.; Fedorov, A. +25 more

Aurora is caused by the precipitation of energetic particles into a planetary atmosphere, the light intensity being roughly proportional to the precipitating particle energy flux. From auroral research in the terrestrial magnetosphere it is known that bright auroral displays, discrete aurora, result from an enhanced energy deposition caused by dow…

2006 • Space Science Reviews

MEx 28

Observation of energy-dependent ionic charge states in impulsive solar energetic particle events

DOI: 10.1016/j.asr.2005.04.042 Bibcode: 2006AdSpR..38..493K

Klecker, B.; Kistler, L. M.; Kucharek, H. +3 more

We measured the mean ionic charge state of Fe in several ³He-rich and heavy-ion rich energetic particle events during the time period 1998 2000. We combined the ionic charge measurements of CELIAS/STOF onboard SOHO (10 100 keV/nuc) with the measurements of SEPICA onboard ACE (180 550 keV/nuc) to investigate the ionic charge distribution…

2006 • Advances in Space Research

SOHO 28