Search Publications
XMM-Newton Observation of PSR B2224+65 and Its Jet
Cheng, K. S.; Takata, J.; Hui, C. Y. +4 more
We have investigated the pulsar PSR B2224+65 and its X-ray jet with XMM-Newton. Apart from the long X-ray jet which is almost perpendicular to the direction of proper motion, a putative extended feature at the pulsar position, which is oriented in the opposite direction to the proper motion, is also suggested by this deep X-ray imaging. Non-detect…
Elusive Ethylene Detected in Saturn's Northern Storm Region
Fletcher, L. N.; Irwin, P. G. J.; Achterberg, R. K. +9 more
The massive eruption at 40°N (planetographic latitude) on Saturn in 2010 December has produced significant and lasting effects in the northern hemisphere on temperature and species abundances. The northern storm region was observed on many occasions in 2011 by Cassini's Composite Infrared Spectrometer (CIRS). In 2011 May, temperatures in the strat…
Herschel Far-infrared Photometric Monitoring of Protostars in the Orion Nebula Cluster
Billot, N.; Megeath, S. T.; Morales-Calderón, M. +2 more
We have obtained time series observations of the Orion Nebula Cluster at 70 µm and 160 µm from the Herschel/PACS Photometer. This represents the first wide-field far-infrared photometric monitoring of a young star-forming region. The acquired 35' × 35' maps show complex extended structures, with unprecedented detail, that trace the int…
Solar Rotation Effects on the Heliosheath Flow near Solar Minima
Pogorelov, Nikolai V.; Borovikov, Sergey N.; Ebert, Robert W.
The interaction between fast and slow solar wind (SW) due to the Sun's rotation creates corotating interaction regions (CIRs), which further interact with each other creating complex plasma structures at large heliospheric distances. We investigate the global influence of CIRs on the SW flow in the inner heliosheath between the heliospheric termin…
The 3.3 µm Polycyclic Aromatic Hydrocarbon Emission as a Star Formation Rate Indicator
Inami, Hanae; Nakagawa, Takao; Oyabu, Shinki +13 more
Polycyclic aromatic hydrocarbon (PAH) emission features dominate the mid-infrared spectra of star-forming galaxies and can be useful to calibrate star formation rates (SFRs) and diagnose ionized states of grains. However, the PAH 3.3 µm feature has not been studied as much as other PAH features since it is weaker than others and resides outs…
Is Active Region Core Variability Age Dependent?
Warren, Harry P.; Ugarte-Urra, Ignacio
The presence of both steady and transient loops in active region cores has been reported from soft X-ray and extreme-ultraviolet observations of the solar corona. The relationship between the different loop populations, however, remains an open question. We present an investigation of the short-term variability of loops in the core of two active r…
Discovery of an Active Supermassive Black Hole in the Bulgeless Galaxy NGC 4561
Ferrarese, L.; Fiore, F.; Mathur, S. +2 more
We present XMM-Newton observations of the Chandra-detected nuclear X-ray source in NGC 4561. The hard X-ray spectrum can be described by a model composed of an absorbed power law with Γ = 2.5+0.4 - 0.3 and column density NH = 1.9+0.1 - 0.2 × 1022 atoms cm-2. The absorptio…
On the Nature of the Progenitor of the Type Ia SN2011fe in M101
Liu, Jifeng; Wang, Tao; Di Stefano, Rosanne +1 more
The explosion of a Type Ia supernova, SN2011fe, in the nearby Pinwheel galaxy (M101 at 6.4 Mpc) provides an opportunity to study pre-explosion images and search for the progenitor, which should consist of a white dwarf (WD), possibly surrounded by an accretion disk, in orbit with another star. We report on our use of deep Chandra observations and …
Dust to Dust: Three Years in the Evolution of the Unusual SN 2008S
Garnavich, P. M.; Kochanek, C. S.; Stanek, K. Z. +5 more
We obtained late-time optical and near-IR imaging of SN 2008S with the Large Binocular Telescope, near-IR data with the Hubble Space Telescope, and mid-IR data with the Spitzer Space Telescope. We find that (1) it is again invisible at optical (UBVR) wavelengths to magnitude limits of approximately 25 mag, (2) while detected in the near-IR (H) at …
Hundred Thousand Degree Gas in the Virgo Cluster of Galaxies
Manset, N.; Sparks, W. B.; Pringle, J. E. +6 more
The physical relationship between low-excitation gas filaments at ~104 K, seen in optical line emission, and diffuse X-ray emitting coronal gas at ~107 K in the centers of many galaxy clusters is not understood. It is unclear whether the ~104 K filaments have cooled and condensed from the ambient hot (~107