1. WHIMEX Doing High Resolution X-ray Spectroscopy Right Webster Cash, Chuck Lillie and the WHIMEx Team Approved for public release, distribution unlimited With Special Thanks to Northrop Grumman for Development and Proposal Support

2. The WHIMEx Team Representative of the Community W. Cash Colorado N. Arav Virginia Tech S. Barber Open U M. Bautz MIT J. Bregman Michigan N. Brickhouse CFA M. Elvis CFA R. Heilman MIT A. Holland Open U A. Hornschemeier GSFC D. Huenemoerder MIT C. LillieNGAS R. McEntafferIowa R. MushotzkyMaryland P. NicastroCFA P. OakleyColorado S. O’Dell MSFC A. PtakGSFC M. Schattenburg MIT M. ShullColorado H. Tsunemi Osaka F. WalterStony Brook L. Winter Colorado S. WolkSA/CfA W. ZhangGSFC Approved for public release, distribution unlimited

3. Designed for the WHIM Problem The WHIM is the highest profile science that we can address in an Explorer The hugely exciting science of AGN’s, stars etc comes free after WHIM problem is solved. IXO Requirement was R~3000, A~1000cm 2 (We fought for a decade to get IXO to raise R above 300) IXO is gone, and there’s nothing else on the high resolution horizon Approved for public release, distribution unlimited

4. Origin of Concept IXO Technology Studies and Older Suborbital Work Science from Decadal Will Zhang’s slumped glass Wolter optics (NUSTAR/IXO) MIT Flat Mirrors and Metrology Web Cash and Randy McEntaffer’s Off-plane Gratings CCD Arrays - Open U, Osaka U, MIT, GSFC Reoptimized for an Explorer Approved for public release, distribution unlimited

5. Reduced Complexity A Single Wolter Mandrel A Single Grating Master 15” Quality 7m Focal Length with Deployable Bench Approved for public release, distribution unlimited

8. Payload Approved for public release, distribution unlimited

9. Figure of Merit Approved for public release, distribution unlimited

10. OVII and OVIII Diagnostic of WHIM 10-03662_1025a_154 Model WHIM Mass Distributions 0.016 0.014 0.012 0.010 0.008 Differential Mass Fraction 765 Log T (K) OVI detection range OVII OVIII Galactic Superwinds No Galactic Superwinds Approved for public release, distribution unlimited

11. Filament Column Densities Approved for public release, distribution unlimited

12. Simulated WHIMEx Spectrum Approved for public release, distribution unlimited

13. WHIMEx AGN Simulations COS WHIMex Chandra Approved for public release, distribution unlimited

14. High Resolution is Essential to Measuring the Basic Parameters (Slide courtesy of Schindhelm and Arav) Shape of line is crucial to separating continuum from saturated line. Without E/  E > 3000, can miss energy outflow by factor of 100! Approved for public release, distribution unlimited

15. 10-03662_1022_154 10 5 0 Counts s -1 A -1 16.716.816.917.017.1 Wavelength (A) Fe XVII AR Lac binary; (  =0.25,  v = 230 km/s) Approved for public release, distribution unlimited

16. Conclusions WHIMEx is Astronomy for and by the community It is the IXO XGS channel repackaged Can be implemented at the low end of the cost scale under consideration. Important Core Science and Exploration that Cannot be Addressed Other Ways Wide Open Guest Observing Can Be Built Now, But Needs Prototype Demonstration Also Needs a Community Statement of Why It is Relevant to the Decadal. There is much mischief between competing disciplines Approved for public release, distribution unlimited