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Galaxy Clusters in the IRAC Dark Field. I. Growth of the Red Sequence
Surace, J. A.; Yan, L.; Krick, J. E. +4 more
Using three newly identified galaxy clusters at z ~ 1 (photometric redshift) we measure the evolution of the galaxies within clusters from high redshift to the present day by studying the growth of the red cluster sequence. The clusters are located in the Spitzer Infrared Array Camera (IRAC) Dark Field, an extremely deep mid-infrared survey near t…
The Intermediate Polar EI UMa: A Prepolar Cataclysmic Variable
Mukai, Koji; Ringwald, F. A.; Welsh, William F. +1 more
We present optical and X-ray time series photometry of EI UMa that reveal modulation at 746 and 770 s, which we interpret as the white dwarf spin and spin-orbit sidebands. These detections, combined with previous X-ray studies, establish EI UMa as an intermediate polar. We estimate the mass accretion rate to be ~3.6 × 1017 g s-1
Modeling UX Ursae Majoris: An Abundance of Challenges
Szkody, Paula; Sion, Edward M.; Godon, Patrick +2 more
We present a system model for optical and far-UV spectra of the nova-like variable UX UMa involving a white dwarf, secondary star, gas stream, hot spot, and accretion disk using our code BINSYN and based on an initially adopted system distance. Calculated SED intensity data successfully fit successive tomographically extracted annuli longward of t…
Ultraviolet Observations of the X-Ray Photoionized Wind of Cygnus X-1 during X-Ray Soft/High State
Bolton, C. T.; Vrtilek, S. D.; Gies, D. +2 more
High-resolution ultraviolet observations of Cygnus X-1 were obtained at two epochs roughly 1 year apart using the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. Orbital phase ranges around phiorb = 0 and 0.5 were covered at each epoch, and the spectra show P Cygni line features from high (N V, C IV, Si IV) and absor…
The Chandra ACIS Survey of M33 (ChASeM33): Investigating the Hot Ionized Medium in NGC 604
Blair, William P.; Hughes, John P.; Ghavamian, Parviz +7 more
NGC 604 is the largest H II region in M33, second only within the Local Group to 30 Dor, and is important as a laboratory for understanding how massive young stellar clusters interact with the surrounding interstellar medium. Here we present deep (300 ks) X-ray imagery of NGC 604 obtained as part of the Chandra ACIS Survey of M33 (ChASeM33), which…
Comparison of Heliospheric In Situ Data with the Quasi-steady Solar Wind Models
Riley, P.; Lepri, S. T.; Antiochos, S. K. +2 more
The standard theory for the solar-heliospheric magnetic field is the so-called quasi-steady model in which the field is determined by the observed magnetic flux at the photosphere and the balance between magnetic and plasma forces in the corona. In this model, the solar magnetic flux that opens to the heliosphere can increase or decrease as the ph…
Helium Line Formation and Abundance during a C-Class Flare
Andretta, Vincenzo; Teriaca, Luca; Mauas, Pablo J. D. +1 more
During a coordinated campaign that took place in 2001 May, a C-class flare was observed both with SOHO instruments and with the Dunn Solar Telescope of the National Solar Observatory at Sacramento Peak. In two previous papers we described the observations and discussed some dynamical aspects of the earlier phases of the flare, as well as the heliu…
The Reddest DR3 SDSS/XMM-Newton Quasars
Elvis, M.; Risaliti, G.; Young, M.
We have cross-correlated the SDSS DR3 Schneider et al. (2005) quasar catalog with the XMM-Newton archive. Color and redshift selections (g - r >= 0.5 and 0.9 < z < 2.1) result in a sample of 17 red, moderate-redshift quasars. The redshift selection minimizes possible contamination due to host galaxy emission and Lyα forest absorption. Bot…
The Solar Eruption of 2005 May 13 and Its Effects: Long-Baseline Interplanetary Scintillation Observations of the Earth-Directed Coronal Mass Ejection
Breen, A. R.; Jackson, B. V.; Bisi, M. M. +7 more
Long-baseline observations of interplanetary scintillation (IPS) provide a unique source of information on solar wind speed and meridional direction across the inner regions of the solar system. We report the results of a series of coordinated IPS observations of an Earth-directed CME. A significant development in the interpretation of these data …
The Chandra ACIS Survey of M33 (ChASeM33): Transient X-Ray Sources Discovered in M33
Mazeh, T.; Williams, Benjamin F.; Sasaki, Manami +7 more
The Chandra ACIS Survey of M33 (ChASeM33) has acquired seven fields of ACIS data covering M33 with 200 ks of exposure in each field. A catalog from the first 10 months of data, along with archival Chandra observations dating back to the year 2000, is currently available. We have searched these data for transient sources that are measured to have a…