We report the discovery and orbital solutions for two new OB binaries in the Cygnus OB2 Association, MT311 (B2V + B3V) and MT605 (B0.5V + B2.5:V). We also identify the system MT429 as a probable triple system consisting of a tight eclipsing 2.97 day B3V+B6V pair and a B0V at a projected separation of 138 AU. We further provide the first spectroscopic orbital solutions to the eclipsing, double-lined, O-star binary MT696 (O9.5V + B1:V), the double-lined, early B binary MT720 (B0-1V + B1-2V), and the double-lined, O-star binary MT771 (O7V + O9V). These systems exhibit orbital periods between 1.5 days and 12.3 days, with the majority having P <6 days. The two new binary discoveries and six spectroscopic solutions bring the total number of known massive binaries in the central region of the Cygnus OB2 Association to 20, with all but two having full orbital solutions.
We present the detection of new cometary X-ray emission lines in the 1.0 to 2.0 keV range using a sample of comets observed with the Chandra Xray observatory and acis spectrometer. We have selected 5 comets from the Chandra sample with good signal-to-noise spectra. The surveyed comets are: C/1999 S4 (linear), C/1999 T1 (McNaught-Hartley), 153P/2002 (Ikeya-Zhang), 2P/2003 (Encke), and C/2008 8P (Tuttle). We modeled the spectra with an extended version of our solar wind charge exchange (SWCX) emission model (Bodewits et al. 2007). Above 1 keV, we find Ikeya-Zhang to have strong emission lines at 1340 and 1850 eV that we identify as being created by solar wind charge exchange lines of Mg XI and Si XIII, respectively, and weaker emission lines at 1470, 1600, and 1950 eV formed by SWCX of Mg XII, Mg XI, andSi XIV, respectively. The Mg XI and XII and Si XIII and XIV lines are detected at a significant level for the other comets in our sample (LS4, MH, Encke, 8P), and these lines promise additional diagnostics to be included in SWCX models.The silicon lines in the 1700 to 2000 eV range are detected for all comets, but with the rising background and decreasing cometary emission, we caution these detections need further confirmation with higher resolution instruments.
Since the initial discovery of cometary charge exchange emission, more than 20 comets have been observed with a variety of X-ray and UV observatories. This observational sample offers a broad variety of comets, solar wind environments and observational conditions. It clearly demonstrates that solar wind charge exchange emission provides a wealth of diagnostics, which are visible as spatial, temporal, and spectral emission features. We review the possibilities and limitations of each of those in this contribution.
Official statistics have not kept pace with the deregulation of the labour market in the 1990s. Beginning in 1992 with the Rose Review' there have been several assessments of the gaps and what is required to plug them. The report of the Prime Ministerial Task Force on Employment in 1994 and the 1996 work of an interdepartmental working group reached similar conclusions about the needs. In the last two years some important advances have occurred. The 1996 Census of Population extended the coverage of education and training topics. Central government funding was obtained for Household Labour Force Survey supplements on education and training (once only) and income (annually). Results from all three supplements will be available in 1997. Feasibility studies, funded by a group of Government agencies, have been done on employer's training practices and expenditure. Statistics New Zealand has developed new classifications for levels of educational attainment and field of educational study. There are still a number of unmet needs, particularly in the areas of labour market dynamics, workplace industrial relations, employment-related business statistics and Maori labour force involvement. Options for funding these have been explored in 1996 with no positive outcomes yet.
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