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High-Resolution X-Ray Imaging of the Center of IC 342
DOI: 10.1086/591023 Bibcode: 2008ApJ...686..995M

Mak, Daisy S. Y.; Pun, Chun S. J.; Kong, Albert K. H.

We present the results of a high-resolution (θFWHM ~ 0.5'') 12 ks Chandra HRC-I observation of the starburst galaxy IC 342 taken on 2006 April 2. We identify 23 X-ray sources within the central 30' × 30' region of IC 342 and resolve the historical ultraluminous X-ray source (ULX), X3, near the nucleus into two sources, namely, C12 and C…

2008 The Astrophysical Journal
XMM-Newton eHST 7
A Systematic Survey of H I Lyα and O VI Doublet Profiles Observed in Polar Coronal Holes at Solar Minimum
DOI: 10.1086/524885 Bibcode: 2008ApJ...674.1167N

Nakagawa, Akinari

A systematic, comprehensive survey of H I Lyα and O VI doublet profiles in polar coronal holes is performed using spectroscopic observation by the SOHO Ultraviolet Coronagraph Spectrometer (UVCS) at solar minimum in 1996-1997. By decomposing coronal hole profiles into component Gaussians, we determine detailed height distributions of profile param…

2008 The Astrophysical Journal
SOHO 6
Relativistic Outflows in Two Quasars in the Chandra Deep Field South
DOI: 10.1086/592141 Bibcode: 2008ApJ...688..116Z

Wang, J. X.; Zheng, Z. Y.

In this paper we provide new 1 Ms Chandra ACIS spectra of two quasars in the Chandra Deep Field South (CDF-S) which had strong and extremely blueshifted X-ray emission/absorption line features in previous 1 Ms spectra, with outflowing bulk velocity v ~ 0.65-0.84c. In the new 1 Ms spectra, the relativistic blueshifted line feature is solidly confir…

2008 The Astrophysical Journal
eHST 5
XMM-Newton Observations of the Red Type 1.8 Quasar 2M1049+5837: Reflection from Cold and Warm (Ionized) Matter
DOI: 10.1086/588039 Bibcode: 2008ApJ...680..110W

Wilkes, B. J.; Pounds, K. A.; Schmidt, G. D.

Chandra observations of the type 1.8, low-redshift (z = 0.115), red (J - KS ~ 2) quasar 2MASSJ 104943+583750 (2M1049+5837) indicated an unusually hard X-ray spectrum (HR ~ 0.6), suggesting obscuration of NH ~ 4 × 1022 cm-2 and a flat Γ ~ 0.4 power-law slope. A higher signal-to-noise ratio XMM-Newton obse…

2008 The Astrophysical Journal
XMM-Newton 5
The Tilted Solar Dipole as Observed and Modeled during the 1996 Solar Minimum
DOI: 10.1086/589684 Bibcode: 2008ApJ...682.1306N

Raouafi, N. -E.; Petrie, G. J. D.; Norton, A. A.

We examine the tilt of the solar magnetic dipole away from the rotational axis near the 1996 solar minimum. A persistent tilted dipole may result from an MHD instability acting on the toroidal bands in the solar interior. Nonaxisymmetric eruption of sunspots has been predicted by dynamo theory and observed in sunspot location patterns. The decay o…

2008 The Astrophysical Journal
SOHO 5
Discovery and Interpretation of an X-Ray Period in the Galactic Center Source CXOGC J174536.1-285638
DOI: 10.1086/592593 Bibcode: 2008ApJ...689.1222M

Muno, Michael P.; Eikenberry, Stephen S.; Bandyopadhyay, Reba M. +1 more

We present X-ray and infrared observations of the X-ray source CXOGC J174536.1-285638. Previous observations suggest that this source may be an accreting binary with a high-mass donor (HMXB) or a colliding wind binary (CWB). Based on the Chandra and XMM-Newton light curve, we have found an apparent 189 +/- 6 day periodicity with better than 99.997…

2008 The Astrophysical Journal
XMM-Newton 4
IC 4406: A Radio-Infrared View
DOI: 10.1086/589228 Bibcode: 2008ApJ...682.1047C

Hora, Joseph L.; Trigilio, Corrado; Cerrigone, Luciano +1 more

IC 4406 is a large (about 100'' × 30'') southern bipolar planetary nebula composed of two elongated lobes extending from a bright central region where there is evidence for the presence of a large torus of gas and dust. We show new observations of this source performed with IRAC (Spitzer Space Telescope) and the Australia Telescope Compact Array. …

2008 The Astrophysical Journal
eHST 4
SUBARU High-Dispersion Spectroscopy of Hα and [N II] 6583 Å Emission in the HH 46/47 Jet
DOI: 10.1086/588644 Bibcode: 2008ApJ...684.1260N

Pyo, Tae-Soo; Takami, Michihiro; Hayashi, Masahiko +2 more

We present slit-scan observations of the Hα and [N II] 6583 Å emission lines toward the HH 46/47 jet with the Subaru Telescope. The spectral resolution of R = 3.6 × 104 allowed us to study the kinematics of individual features in unprecedented detail. The spectra show (1) the main jet component (VLSR ~ - 160 km s-1

2008 The Astrophysical Journal
eHST 4
RX J1648.7+6109: Witnessing the Formation of a Massive Group/Poor Cluster and Its Brightest Galaxy
DOI: 10.1086/590550 Bibcode: 2008ApJ...685..138J

Mulchaey, John S.; Lubin, Lori M.; Jeltema, Tesla E.

Using deep Chandra and optical spectroscopic observations, we investigate an intriguing young massive group, RX J1648.7+6109, at z = 0.376, and we combine these observations with previous measurements to fit the scaling relations of intermediate-redshift groups and poor clusters. RX J1648 appears to be in an early stage of formation; while it foll…

2008 The Astrophysical Journal
eHST 4
A Search for Temperature and Density Variations in NGC 7027 with the Hubble Space Telescope
DOI: 10.1086/528676 Bibcode: 2008ApJ...676..390B

Bieging, John H.; Tielens, A. G. G. M.; Boley, Paul A. +1 more

We observed the young planetary nebula NGC 7027 with the HST Imaging Spectrograph (STIS) in long-slit mode at five slit positions along the major axis of the nebula, over the wavelength range from 3000 to ~10,000 Å. We used dereddened line ratios to determine line-of-sight average values for (1) He++ and He+ ionization fracti…

2008 The Astrophysical Journal
eHST 4