Search Publications
A Two-dimensional Map of the Color Excess in NGC 3603
Grebel, Eva K.; Pang, Xiaoying; Pasquali, Anna
Using archival Hubble Space Telescope/Wide Field Camera 3 images centered on the young HD 97950 star cluster in the giant H II region NGC 3603, we computed the pixel-to-pixel distribution of the color excess, E(B - V)g, of the gas associated with this cluster from its Hα/Paβ flux ratio. At the assumed distance of 6.9 kpc, the resulting …
Observation of a Sharp Negative Dipolarization Front in the Reconnection Outflow Region
Zhou, Meng; Deng, Xiao-Hua; Pang, Ye +1 more
A sharp dipolarization front (DF) has recently been detected in the Earth's magnetotail and is associated with complex kinetic effects. We present one event where a tailward propagating negative DF (with Bz decreasing sharply to negative value) was observed near a reconnection region. The thickness of the negative DF is comparable with …
The X-Ray Counterpart of the High-B Pulsar PSR J0726-2612
van Kerkwijk, M. H.; Speagle, J. S.; Kaplan, D. L.
Middle-aged, cooling neutron stars are observed both as relatively rapidly spinning radio pulsars and as more slowly spinning, strongly magnetized isolated neutron stars (INSs), which stand out by their thermal X-ray spectra. The difference between the two classes may be that the INSs initially had much stronger magnetic fields, which decayed. To …
TC-1 observations of a flux rope: Generation by multiple X line reconnection
Rème, H.; Cao, J. B.; Carr, C. M. +2 more
On 29 December 2004 the Double Star TC-1 satellite most probably stays close to a reconnection line for about 20 min. The direction of the X line can be evaluated according to the component merging model. During the time of observations, TC-1 also detects a flux transfer event (FTE). It is found that the FTE axis is parallel to such an X line. Thi…
Comparison between Cassini and Voyager observations of Jupiter's decametric and hectometric radio emissions
Imai, Masafumi; Imai, Kazumasa; Higgins, Charles A. +1 more
In this paper, we attempt to clarify the relationship between Jovian hectometric (HOM) and non-Io-related decametric (non-Io-DAM) radio structure. For that purpose, we extend the analysis by including more data and investigating statistical properties of the Jovian DAM and HOM radio emissions based on Cassini and Voyager observations, especially b…
The origin of gas in extended narrow-line regions of nearby Seyfert galaxies - I. NGC 7212
Moiseev, A. V.; La Mura, G.; Ciroi, S. +6 more
The extended narrow-line region (ENLR) of an active galactic nucleus (AGN) is a region of highly ionized gas with a size of a few up to 15-20 kpc. When it shows a conical or biconical shape with the apexes pointing towards the active nucleus, this region is also called an ionization cone. Ionization cones are evidence of the unified model, which p…
Herschel Observations of the T Cha Transition Disk: Constraining the Outer Disk Properties
Henning, Thomas; Pinte, Christophe; Cieza, Lucas A. +7 more
T Cha is a nearby (d ~ 100 pc) transition disk known to have an optically thin gap separating optically thick inner and outer disk components. Huélamo et al. recently reported the presence of a low-mass object candidate within the gap of the T Cha disk, giving credence to the suspected planetary origin of this gap. Here we present the Herschel pho…
Solar-cycle variation of zonal and meridional flow
Howe, R.; Komm, R.; Hill, F. +2 more
We study the variation with the solar cycle of the zonal and meridional flows in the near-surface layers of the solar convection zone. We have analyzed MDI Dynamics-Program data with ring-diagram analysis covering the rising phase of cycle 23, while the analyzed GONG high-resolution data cover the maximum and declining phase of cycle 23. For the z…
Detection of Brown Dwarf Like Objects in the Core of NGC 3603
McCarthy, Patrick J.; Calzetti, Daniela; Whitmore, Bradley C. +23 more
We used near-infrared data obtained with the Wide Field Camera 3 on the Hubble Space Telescope to identify objects having the colors of brown dwarfs (BDs) in the field of the massive galactic cluster NGC 3603. These are identified through a combination of narrow- and medium-band filters which span the J and H bands and are particularly sensitive t…
Uncovering the Wave Nature of the EIT Wave for the 2010 January 17 Event through Its Correlation to the Background Magnetosonic Speed
Wu, S. T.; Feng, X. S.; Jiang, C. W. +3 more
An EIT wave, which typically appears as a diffuse brightening that propagates across the solar disk, is one of the major discoveries of the Extreme ultraviolet Imaging Telescope on board the Solar and Heliospheric Observatory. However, the physical nature of the so-called EIT wave continues to be debated. In order to understand the relationship be…