5/21/2015G.C.Stewart Berlin 1 ASTROSAT: A Multi-Wavelength Satellite 1st Dedicated Indian Astronomical Mission ISRO Satellite Centre (ISAC), Bangalore Tata Institute of Fundamental Research, Mumbai University of Leicester Indian Institute of Astrophysics (IIA), Bangalore Inter-University Centre for Astronomy & Astrophysics (IUCAA), Pune. Canadian Space Agency Raman Research Institute, Bangalore Vikram Sarabhai Space Centre, Trivandrum X-RAY UV/Opt

5/21/2015G.C.Stewart Berlin 2 ASTROSAT (1.55 tons  600 kms, nearly equatorial orbit by PSLV, 3 gyros and 2 star trackers for attitude control by reaction wheel system with a Magnetic torquer ) Soft X-ray Telescope 3 Large Area Xenon Proportional Counters 2 UV(+Opt ) Imaging Telescopes CZTI Folded Solar panels Radiator Plates For SXT and CZT Scanning Sky Monitor (SSM)

5/21/2015G.C.Stewart Berlin 3 UVIT: Two Telescopes  f/12 RC Optics  Focal Length: 4756mm  Diameter: 38 cm  Simultaneous Wide Angle ( ~ 28’) images in FUV ( nm) in one and NUV ( nm) & VIS ( nm) in the other  MCP based intensified CMOS detectors  Spatial Resolution : 1.8”  Sensitivity in FUV: mag. 20 in 1000 s  Temporal Resolution ~ 30 ms, full frame ( < 5 ms, small window )  Gratings for Slit-less spectroscopy in FUV & NUV  R ~ 100

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5/21/2015G.C.Stewart Berlin 5 UVIT: filters

5/21/2015G.C.Stewart Berlin 6 GALEX UVIT FoV (Circular dia) 1.24 degrees 27 arc-min No. of bands 2 (NUV, FUV) 2 channels (NUV, FUV) + Vis Filters in NUV NIL 5 filters Filters in FUV NIL 5 filters [multiple colour-colour diagrams] Spectroscopy Grism Grating Resolution R ~ R ~ 100 No. of grism/grating 1 per band 2 per band Angular resolution arcsec 1.8 arc-sec (FWHM) Saturation < 10 mag < 8.0 mag (neutral density filter) [can image fields with bright objects] Time resolution ~ 10 milli-sec ~ 5.0 milli-sec (window mode) ~ 30 milli-sec full field

Energy Range: 3-80 keV (50  Mylar window, 2 atm. of 90 % Xenon + 10 % Methane) Effective Area :6000 cm² 20 keV) Energy Resolution :~10% FWHM at 22 keV Field of View:1° x 1° FWHM (Collimator : 50µ Sn + 25µ Cu + 100µ Al ) Blocking shield on sides and bottom : 1mm Sn mm Cu Timing Accuracy:10 μsec in time tagged mode (oven-controlled oscillator). Onboard purifier for the xenon gas Large Area Xenon Proportional Counter (LAXPC): Characteristics 5/21/2015G.C.Stewart Berlin 7

5/21/2015G.C.Stewart Berlin 8 LAXPC: Effective Area

Large Area X-ray Proportional Counter (LAXPC) 5/21/2015G.C.Stewart Berlin 9

5/21/2015G.C.Stewart Berlin 10 LAXPC: Collimator

CZT Imager characteristics Area1024 cm 2 Pixels16384 Pixel size2.4 mm X 2.4 mm (5 mm thick) Read-outASIC based (128 chips of 128 channels) Imaging methodCoded Aperture Mask (CAM) Field of View17 X 17 deg 2 (uncollimated) 6 X 6 (10 – 100 keV) – CAM Angular resolution8 arcmin Energy 100 keV Energy range10 – 100 keV - Up to 1 MeV (Photometric) Sensitivity0.5 mCrab (5 sigma; 10 4 s) 5/21/2015 G.C.Stewart Berlin 11

CZT-Imager with a coded mask (Qualification Model) 5/21/2015G.C.Stewart Berlin 12

CZT Detector 4 cm X 4 cm CZT crystal Connectors HV Connector Thermal conductor Thermal conductor ASIC 5/21/2015G.C.Stewart Berlin 13

5/21/2015G.C.Stewart Berlin 14 SXT Characteristics Telescope Length: 2465 mm (Telescope + camera + baffle + door) Top Envelope Diameter: 386 mm Focal Length: 2000 mm Epoxy Replicated Gold Mirrors on Al substrates in conical Approximation to Wolter I geometry. Radius of mirrors: mm; Reflector Length: 100 mm Reflector thickness: 0.2 mm (Al) + Epoxy (~50 microns) + gold (1400 Angstroms) Minimum reflector spacing: 0.5 mm No. of reflectors: 320 (40 per quadrant) Detector (Swift Heritage): E2V CCD x 600 Field of view: 41.3 x 41.3 arcmin PSF: 3 – 4 arcmins Sensitivity (expected): few x cgs (1 cps/mCrab)

5/21/2015G.C.Stewart Berlin 15 Soft X-ray Telescope

5/21/ Four Fe-55 calibration (corner) sources One Fe 55 calibration door source Optical Blocking Filter CCD Assy. including TEC PCB with front-end electronics G.C.Stewart Berlin

5/21/2015G.C.Stewart Berlin 17 SXT Engineering and Flight Models

Astrosat SXT FM FPCA in Thermal Vacuum Chamber at Birmingham University 5/21/2015G.C.Stewart Berlin 18

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X-ray Reflectivity Smoothness of 8 – 10 Angstroms 5/21/2015G.C.Stewart Berlin 20

5/21/2015G.C.Stewart Berlin 21 CCD Performance Nominal Noise ~6 – 10 e - Resolution at Mn ~157 eV (Lab Electronics)

SXT CCD (Eng.) Data with TIFR built Electronics 5/21/ and 6.4 keV peaks Si escape peaks 3.70 and 4.15 keV Isolated pixels only Resolution ~140 eV G.C.Stewart Berlin

Door and Corner X-ray Calibration Sources Optical LED Image 5/21/2015G.C.Stewart Berlin 23

SXT Effective Area vs. Energy (after subtraction of shadowing effects due to holding structure) 5/21/ G.C.Stewart Berlin

SXT Half Power Diameter for a point source at 1 keV 5/21/ G.C.Stewart Berlin

Galactic centre with SXT 5/21/2015G.C.Stewart Berlin 26

Scanning Sky Monitor (SSM)  Detector : 3 x Proportional counters with resistive anodes  Ratio of signals on either ends of anode gives position.  Energy Range : keV  Position resolution : 1.5 mm  Field of View : 10 o x 90 o (FWHM)  Sensitivity : 30 mCrab (5 min integration)  Time resolution : 1 ms  Angular resolution : ~ 10 arc min 5/21/2015G.C.Stewart Berlin 27

5/21/2015G.C.Stewart Berlin 28 Status  Engineering Environmental Tests almost complete  Flight Model Construction Well Advanced (UVIT detectors and SXT CCD camera complete)  Spacecraft Assembly begun – most subsystems complete  Launcher Assigned  Launch Date

ASTROSAT – Key Strengths  Simultaneous V/UV to hard X-ray measurements  LEO+ 7 0 inclinclination  Low, stable? Background  Large area at high X-ray energies  UV imaging capability  Low pile-up in CCD  Fast Slewing ?? 5/21/2015G.C.Stewart Berlin 29

ASTROSAT – Key Projects 1.AGN/Binaries: Simultaneous UV to hard X-ray timing/monitoring 2.Galactic Novae: UV to X-ray Observations (TOO program) 3.Magnetars: Multi-wave observations 4.LMXBs: Persistent Pulsations and thermonuclear bursts 5.Galactic Black Holes and micro / nano quasars 6.Binary X-ray Pulsars: Cyclotron Resonance Scattering Features (X-ray Observations) 7.Clusters of galaxies: X-ray & UV Observations 5/21/2015G.C.Stewart Berlin 30

ASTROSAT – Key Projects 10.Supernova Remnants: X-ray and UV Observations 11.UVIT observations of a) Star Forming galaxies, b) Young stellar objects, c) Galactic Structure, d) Proto- and Planetary Nebulae e) UV Extinction in the Galaxy (Archival Data) 12.Miscellaneous: a) Study nano quasars and Compton thick sources, b) Observations of Stellar Flares, c) GLAST/INTEGRAL/BAT Sources, d) Surveys - multi wave, deep fields 5/21/2015G.C.Stewart Berlin 31

AGN (bright) 4/5 decade SEDs - Resolving all the spectral components : UV and soft X-rays (thermal) from accretion disk, hard X-ray reflection component, intrinsic power-law component Variability correlation and lags between UV, soft and hard X-rays Variability correlation and lags between Fe-K line and Compton Reflection Bright Compton thick 5/21/2015G.C.Stewart Berlin 32

Large X-ray bandwidth and hard X-ray sensitivity with low background: Clusters of galaxies Science Drivers Measure temperature/abundance out to the virial radius and thus measure their total mass Measure the hard X-ray (non-thermal) emission component – its relation with the motions of central bright galaxies, and large scale magnetic field 5/21/2015G.C.Stewart Berlin 33

5/21/2015G.C.Stewart Berlin 34 SXT: Clusters of galaxies C SXT LAXPC CZTI H Spectral model from Rephaeli et al. (1999)

5/21/2015G.C.Stewart Berlin 35 Studying C-thin and C-thick AGN: CXB N H in cm ~ x x >

Binary X-ray Pulsars with Astrosat Simulated 10 ks observations of hard X-ray spectrum of Accreting Pulsar 4U The cyclotron lines are well resolved by ASTROSAT 5/21/2015G.C.Stewart Berlin 36

5/21/2015G.C.Stewart Berlin 37 PV Phase (6 months) Guaranteed Time (6 months 2 nd Year3 rd Year3+? Yr X-ray Teams67% 32.5%20%_ UVIT Team33% 17.5%10%_ Indian Proposals __35%45%65% International Proposals ___10%20% Canada__5% Leicester__3% TOO__5% Calibration__2% Time Allocation

5/21/2015G.C.Stewart Berlin 38 Coming Next Year !

Simultaneous UV to hard X-ray spectral measurements with ASTROSAT: Blazars, HPQs, OVVs etc. Science Drivers: Jet Physics, particle injection and acceleration Synchrotron X-ray emission from the highest energy e- Electron/proton injection. Acceleration and cooling related variability patterns in Sync. components of FSRQs and LBLs. UV and soft X-ray variability can pin down the transition between the emission from slow and fast cooling e- and thus obtain estimates of magnetic field and Doppler factors of the jets. Shocks in jets. Geom: viewing angle, jet opening angle. Underlying Accretion disk in Blazars ? Can be revealed during minima when the beamed component is suppressed. 5/21/2015G.C.Stewart Berlin 39