Search Publications
Decorrelation Times of Photospheric Fields and Flows
Welsch, B. T.; Kusano, K.; Yamamoto, T. T. +1 more
We use autocorrelation to investigate evolution in flow fields inferred by applying Fourier local correlation tracking (FLCT) to a sequence of high-resolution (0farcs3), high-cadence (sime 2 minute) line-of-sight magnetograms of NOAA active region (AR) 10930 recorded by the narrowband filter imager of the Solar Optical Telescope aboard the Hinode …
Characterization of the X-Ray Light Curve of the γ Cas-like B1e Star HD 110432
Smith, Myron A.; Motch, Christian; Lopes de Oliveira, Raimundo
HD 110432 (BZ Cru B1Ve) is the brightest member of a small group of "γ Cas analogs" that emit copious hard X-ray flux, punctuated by ubiquitous "flares." To characterize the X-ray time history of this star, we made a series of six RXTE multi-visit observations in 2010 and an extended observation with the XMM-Newton in 2007. We analyzed these new l…
Identification of Galactic Bulge Survey X-Ray Sources with Tycho-2 Stars
Maccarone, T. J.; Torres, M. A. P.; Nelemans, G. +6 more
We identify 69 X-ray sources discovered by the Galactic Bulge Survey (GBS) that are coincident with or very close to bright stars in the Tycho-2 catalog. Additionally, two other GBS sources are resolved binary companions to Tycho-2 stars where both components are separately detected in X-rays. Most of these are likely to be real matches, but we id…
The Mass-Richness Relation of MaxBCG Clusters from Quasar Lensing Magnification Using Variability
Baltay, Charles; Rabinowitz, David; Bauer, Anne H. +3 more
Accurate measurement of galaxy cluster masses is an essential component not only in studies of cluster physics but also for probes of cosmology. However, different mass measurement techniques frequently yield discrepant results. The Sloan Digital Sky Survey MaxBCG catalog's mass-richness relation has previously been constrained using weak lensing …
RW Aur A from the X-Wind Point of View: General Features
Liu, Chun-Fan; Shang, Hsien
In this paper, the RW Aur A microjet is studied from the point of view of X-wind models. The archived Hubble Space Telescope/STIS spectra of the optical forbidden lines [O I], [S II], and [N II] from RW Aur A, taken in Cycle 8 with seven parallel slits along the jet axis, spaced at 0farcs07 apart, were analyzed. Images, position-velocity diagrams,…
Disturbed Zone and Piston Shock Ahead of Coronal Mass Ejection
Eselevich, M.; Eselevich, V.
The 2010 June 13 coronal mass ejection (CME) propagating toward the position angle P.A. ≈ 245° (measured counterclockwise from the Sun's north pole) was studied from the SDO/AIA and SOHO/LASCO C2, C3 data. We show that ahead of the CME frontal structure, as a result of its interaction with the undisturbed solar wind, a disturbed region (with an in…
Three-dimensional Structure and Evolution of Extreme-ultraviolet Bright Points Observed by STEREO/SECCHI/EUVI
Moon, Yong-Jae; Chae, Jongchul; Zhang, Jie +4 more
We unveil the three-dimensional structure of quiet-Sun EUV bright points and their temporal evolution by applying a triangulation method to time series of images taken by SECCHI/EUVI on board the STEREO twin spacecraft. For this study we examine the heights and lengths as the components of the three-dimensional structure of EUV bright points and t…
Physical Properties of Lyα Emitters at z ~ 0.3 from UV-to-FIR Measurements
Berta, S.; Magnelli, B.; Lutz, D. +25 more
The analysis of the physical properties of low-redshift Lyα emitters (LAEs) can provide clues in the study of their high-redshift analogs. At z ~ 0.3, LAEs are bright enough to be detected over almost the entire electromagnetic spectrum and it is possible to carry out a more precise and complete study than at higher redshifts. In this work, we exa…
Early Ultraviolet Observations of a Type IIn Supernova (2007pk)
Brown, P. J.; Oates, S. R.; Holland, S. T. +6 more
We present some of the earliest UV observations of a Type IIn supernova (SN)—SN 2007pk, where UV and optical observations using Swift's Ultra-Violet/Optical Telescope began 3 days after discovery or ~5 days after shock breakout. The SN observations commence at approximately maximum light in the UV and u-band filters, suggesting that the UV light c…
Preprocessing Magnetic Fields with Chromospheric Longitudinal Fields
Kusano, K.; Yamamoto, Tetsuya T.
Nonlinear force-free field (NLFFF) extrapolation is a powerful tool for the modeling of the magnetic field in the solar corona. However, since the photospheric magnetic field does not in general satisfy the force-free condition, some kind of processing is required to assimilate data into the model. In this paper, we report the results of new prepr…