ESA’s INTEGRAL Mission and US support for it Gerry Skinner Univ. Md / CRESST / NASA-GSFC Neil Gehrels NASA-GSFC 1

INTEGRAL Mission Summary ESA-led Gamma-Ray Mission with significant US and Russian Participation Launch October 17, 2002 Operations approved by ESA until at least Dec 2012 Science Gamma-ray astronomy (20 keV – 10 MeV) 2 Main gamma-ray instruments – SPI (spectrometer) & IBIS (imager) INTEGRAL is the only operating or planned mission providing imaging and spectrometry in the MeV energy band SPI Ge Detectors IBIS JEM-X SPI OMC IBIS CdTe Detectors 2 2 2

Integral Mission highlights First detection of polarization in hard X-rays from the Crab nebula - high significance result with independent confirmation by two teams using different instrument configurations Discovery of supergiant fast X-ray transients and their recognition as a new class of High Mass X-ray Binaries Gamma-ray line astronomy First clear detection of 1173 and 1333 keV 60Fe lines Mapping of 26Al 1809 keV line in galactic distribution and velocity space Mapping of 511 keV positron annihilation radiation; detection of asymmetry in disk emission Key role in detecting highly obscured sources Extragalactic: Obscured AGN Galactic : highly absorbed transients Discovery of hard powerlaw spectral components in the quiescent emission of many AXPs and SGRs INTEGRAL has played a key role in detecting highly obscured AGN, finding that obscured AGN are rarer than required by earlier explanations of the CXB. The discovery of hard powerlaw spectral components in the quiescent emission of six AXPs and SGRs, lending support to the resonant Compton upscattering model. 3

Highlights 1 Gamma-ray Polarization of the Crab Nebula SPI: Dean et al. Science 2008; IBIS: Forot et al ApJ 2008 π = 46 ± 10 % Ψ = 123° ± 10°  aligned with pulsar spin axis Two independent analyses using different Integral instruments reach highly consistent conclusions 0.1 - 1 MeV ; 0.2-0.8 MeV More tentative detections of polarization in 2 GRBs and in Cyg X-1 4

Highlights 2 Gamma-ray line spectroscopy 26Al 1809 keV line Galactic distribution mapped Doppler shifts due to rotation measurable 60Fe 1173 & 1332 keV lines Ratio 26Al : 60Fe 0.25 ± 0.09 constrains mixing and IMF of massive stars 511 keV e+ annhilation line Strong central bulge inconsistent with 26Al decay chain being dominant origin of positrons Unexpected asymmetry in inner disk emission 5

The US Role in Integral Flight Hardware contribution to SPI Spectrometer Pulse Shape Discrimination system (UCSD, UCB) Support ceased 2008 Provision of Ground Support Equipment and technical design input for IBIS Imager (MSFC) Support ceased 2008 One US Mission Scientist (Teegarden) Support ceased 2008 Software and analysis system support for SPI (GSFC) Support ceased 2008 Timing analysis software; Response matrix calculation and updates Software support at the Integral Science Data Centre (ISDC), Geneva Support ceased 2008 Provision of Goldstone ground station Still available to ESA, but no longer needed Funding for US PIs and Co-Is with successful Guest Observer proposals Support ceased 2010 US Guest Observer Facility Support ceased 2010; limited support through HEASARC US Data Archive Mirror Support continues through HEASARC PSD to reduce BG Software support at ISDC - one software person supported at the Geneva Integral Science Data Center through development 6

US Refereed Publications US Scientist Participation in Observations Statistics up to 2010 137 winning GI proposals with US PIs in AO-1 to 7 (18.5% of total) 55% of AO-6 and AO-7 proposals have US participation ~35 proposals from ~15 institutions funded per year 83 US first author publications (12% of total) 246 US author publications (37% of total) 368 ATELs containing either INTEGRAL direct or follow-up observations 16% of all ATELs 2003-present US Refereed Publications 7 7

Impact of termination of NASA support No GI program funding - US scientists with Integral time must find other funding sources (e.g. ADAP) or leave active participation to Non-US collaborators. No GOF ; no user support Negative message to ESA when they consider further mission extensions Potential problem if further SPI detectors fail and a modified response matrix is needed But mirror archive will continue at HEASARC (subject to 2011 Senior Review recommendations being endorsed) 7 Pis doesn’t sound much, but only 98 were approved world-wide (Integral observations tend to be long) Dont know if any ADAP proposals were submitted 8

INTEGRAL project and ADAP funding of US PIs and Co-Is + in ADAP 07 there were 3 INTEGRAL-related proposals of which 1 was funded at $146K over 3 years 9