Search Publications
XMM-Newton Observations of MBM 12: More Constraints on the Solar Wind Charge Exchange and Local Bubble Emissions
Snowden, Steven L.; Smith, Randall K.; Plucinsky, Paul P. +3 more
We present the first analysis of an XMM-Newton observation of the nearby molecular cloud MBM 12. We find that in the direction of MBM 12 the total O VII (0.57 keV) triplet emission is 1.8+0.5 -0.6 photons cm-2 s-1 sr-1 (or line units, LU) while for the O VIII (0.65 keV) line emission we find a…
Maximum Coronal Mass Ejection Speed as an Indicator of Solar and Geomagnetic Activities
Goode, P. R.; Gopalswamy, N.; Yurchyshyn, V. B. +4 more
We investigate the relationship between the monthly averaged maximal speeds of coronal mass ejections (CMEs), international sunspot number (ISSN), and the geomagnetic Dst and Ap indices covering the 1996-2008 time interval (solar cycle 23). Our new findings are as follows. (1) There is a noteworthy relationship between monthly averaged maximum CME…
Multiwavelength Observations of the Gamma-Ray Blazar PKS 0528+134 in Quiescence
Lähteenmäki, A.; Umana, G.; Lott, B. +29 more
We present multiwavelength observations of the ultraluminous blazar-type radio loud quasar PKS 0528+134 in quiescence during the period 2009 July-December. Four Target-of-Opportunity observations with the XMM-Newton satellite in the 0.2-10 keV range were supplemented with optical observations at the MDM Observatory, radio and optical data from the…
Probing Population III Stars in Galaxy IOK-1 at z = 6.96 Through He II Emission
Fan, Xiaohui; Jiang, Linhua; Cai, Zheng +7 more
The He II λ1640 emission line has been suggested as a direct probe of Population III (Pop III) stars at high redshift, since it can arise from highly energetic ionizing photons associated with hot, metal-free stars. We use the Hubble Space Telescope WFC3/F130N IR narrowband filter to probe He II λ1640 emission in galaxy IOK-1 at z = 6.96. The sens…
Forward Modeling Cavity Density: A Multi-instrument Diagnostic
Gibson, S. E.; Schmit, D. J.
The thermodynamic properties of coronal prominence cavities present a unique probe into the energy and mass budget of prominences. Using a three-dimensional morphological model, we forward model the polarization brightness and extreme-ultraviolet (EUV) emission of a cavity and its surrounding streamer. Using a genetic algorithm, we find the best-f…
The Rest-frame Ultraviolet Light Profile Shapes of Lyα-emitting Galaxies at z = 3.1
Blanc, Guillermo A.; Gronwall, Caryl; Gawiser, Eric +4 more
We present a morphological analysis of the rest-frame ultraviolet emission of 78 resolved, high signal-to-noise z ~ 3.1 Lyα emitters (LAEs) in the Extended Chandra Deep Field-South. Using Hubble Space Telescope/Advanced Camera for Surveys V-band images taken as part of the Galaxy Evolution from Morphology and SEDs, Great Observatories Origins Deep…
Imaging the Time Evolution of Eta Carinae's Colliding Winds with HST
Corcoran, Michael F.; Gull, Theodore R.; Madura, Thomas I. +1 more
We report new Hubble Space Telescope/Space Telescope Imaging Spectrograph observations that map the high-ionization forbidden line emission in the inner arcsecond of Eta Car, the first that fully image the extended wind-wind interaction region of the massive colliding wind binary. These observations were obtained after the 2009.0 periastron at orb…
Four New Black Hole Candidates Identified in M31 Globular Clusters with Chandra and XMM-Newton
Murray, S. S.; Barnard, R.; Garcia, M. +2 more
We have identified four new black hole candidates (BHCs) in M31 globular clusters (GCs) using 123 Chandra and 4 XMM-Newton observations of the M31 central region. The X-ray source associated with Bo 163 (XB163) is a recurrent transient with the highest observed luminosity, ~1.4× 1038 erg s-1, considerably brighter than any ou…
Clues to the Star Formation in NGC 346 across Time and Space
Panagia, Nino; Sabbi, Elena; De Marchi, Guido
We have studied the properties of the stellar populations in the field of the NGC 346 cluster in the Small Magellanic Cloud, using the results of a novel self-consistent method that provides a reliable identification of pre-main sequence (PMS) objects actively undergoing mass accretion, regardless of their age. The 680 identified bona fide PMS sta…
Long-term Evolution of Magnetic and Dynamical Properties in A Sunspot Light Bridge
Shimizu, Toshifumi
Sunspot light bridges (LBs)—long bright lanes appearing in umbra—sometimes show dynamical behaviors such as plasma ejections, brightenings, and fast gas flows in the photosphere and lower chromosphere, but we have not understood what causes these dynamics. The Hinode Solar Optical Telescope successfully captured the entire period of the evolution …