Welcome to the 4 th Chandra CIAO

Welcome to the 4 th Chandra – CIAO Workshop 20 – 22 May 2002 Martin Elvis Smithsonian Astrophysical Observatory Chandra X-ray Center

Chandra X-ray Observatory Overview Martin Elvis Smithsonian Astrophysical Observatory CIAO Workshop 20 May 2001 Chandra X-ray Center

NASA Great Observatories CHANDRA Chandra X-ray Center

Focusing X-rays Chandra X-ray Center

Chandra Mission Summary u Launch: July 23, 1999 – STS-93/ Inertial Upper Stage / Integral Propulsion System – 10, 000 km x 140, 000 km, 28. 4 o Inclined Orbit u Design Lifetime > 5 Years (in NASA plan for 10 year life) u 10 -m Focal Length Wolter -1 Mirror: 4 nested Mirror Pairs Energy Range: 0. 1 -10 ke. V u u¼ u arcsecond resolution. Sub-0. 5 arcsec in practice 2 Imaging Focal Plane Science Instruments – ACIS (Advanced CCD Imaging Spectrometer) – HRC (High Resolution Camera) u 2 Objective Transmission Gratings for Dispersive Spectroscopy – LETG (Low-Energy Transmission Grating) – HETG (High-Energy Transmission Grating) Chandra X-ray Center

Mission and Observatory Description Chandra X-ray Center

High Resolution Mirror Assembly u u u 4 pairs of concentric thin-walled zerodur, grazing incidence Wolter Type-I mirrors >large area. ->800 cm 2 E<2 ke. V Antennae galaxies figured to 0. 5” FWHM -> sensitivity, -> megapixel images Focal length 10 m. -> response to 10 ke. V Many independent pixels High sensitivity Iridium edge u polished to 3 A -> low scattering high dynamic range PSR nebula PKS 1127 -145 95% High energy sources 1. 6” Chandra X-ray Center 100: 1 AGN/jet contrast

Aspect Camera and Fiducial Transfer System Aspect Camera 4. 25 inch dia. 15”pixels <0. 25” r ms (typical) Chandra X-ray Center

Chandra Science Instruments u ACIS-I Advanced CCD Imaging Spectrometer (ACIS) – CCD array with 16’x 16’ field of view (ACIS-I) – grating readout array (ACIS-S) u Z+ BI High Resolution Camera (HRC) – microchannel plate imager with 31’x 31’ field of view (HRC-I) – low energy grating readout array (HRC-S) – High time resolution u High Energy Transmission Grating Spectrometer (HETG) BI Y+ ACIS-S HRC-I – transmission grating pairs for medium and high energy u Low Energy Transmission Grating Spectrometer (LETG) – transmission grating for low energy Chandra X-ray Center HRC-S

Advanced CCD Imaging Spectrometer (ACIS) u Ten 1024 x 1024 pixel CCDs (any 6 simultaneously) – Intrinsic energy resolution ~100 e. V -> imaging spectroscopy – ACIS-I: 2 x 2 array for imaging (16 x 16 arcmin) – ACIS-S: 1 x 6 array for imaging (8 x 8 arcmin) or spectroscopy – 2 `back illuminated’ (BI) chips: good low E QE, higher throughput Chandra X-ray Center

CTI u u ACIS Issues Front Iluminated (FI) chips suffered proton damage just after launch. -> charge transfer inefficiency (CTI) -> much degraded energy resolution CTI correction (Townsley, PSU) restores linearity, most d. E/E Pileup u u 3. 2 s full frame readout time -> for sources >0. 1 ct/s suffer “pileup” I. e. 2 photons in same pixel/frame -> loss of energy information, and -> loss of PSF peak Pileup correction (J. Davis, MIT) available in CIAO, Sherpa Low Energy Calibration u u u Chandra X-ray Center Non-linear gain Changing QE See H. Donnely talk

Chandra Grating Spectrometers m=2 Incoming Radiation d m=1 m=0 m=-1 m = d sin Chandra X-ray Center m=-2

Grating Spectrometers: HETG u HETG: High Energy Transmission Gratings – Designed for use with ACIS-S providing E/delta(E) to 1000 between 0. 4 and 10. 0 ke. V – Two sets of gratings – Medium Energy Gratings (MEG) use outer 2 mirrors – High Energy Gratings (HEG) use inner 2 mirrors – Mounted at different angles to form an “X” dispersed pattern Capella HETG spectrum Chandra X-ray Center

Grating Spectrometers: LETG u LETG High Energy Transmission Gratings – – Provides highest resolving power at low energies Designed for use with HRC-S with 0. 07 – 7. 29 ke. V E/delta(E) > 1000 for 0. 07 < E < 0. 15 ke. V E/delta(E) < 1000 for E > 0. 15 ke. V Chandra X-ray Center

Chandra Operations u u u Mission science plan converted to command loads and uplinked to Chandra X-ray events collected and stored on Solid-State Recorders (SSR) Ground contact established every ~8 hours through Deep Space Network – SSR data downlinked – new command load uplinked (up to 72 hours of stored commands) u Data transferred to OCC through JPL for science processing Chandra X-ray Center ssssssssssss CXO CXC OCC

6. Chandra X-ray Center Architecture uplink downlink

Chandra Observing Cycle u u High (66%) observing efficiency TOOs, solar flares ->big hit on mission planning team Annual Proposal Cycle: Next Deadline: 15 March 2003 (anticipated) u u + Archive, Theory grants Funding expected to 2009 Chandra X-ray Center

enjoy the workshop! Chandra X-ray Center