ASTROSAT LAXPC

Biswajit PaulRaman Research Institute, Bangalore

On behalf of the LAXPC Team

ASTROSAT

EXOSAT-ME : 1983-19861.5-15 keV, 1800 sq cmWith LE Imaging Telescopes (CMA)

GINGA-LAC: 1987-19912-37 keV, 4000 sq cmWith All Sky Monitor

RXTE-PCA: 1996-200?2-30 keV, 6000 sq cmAll Sky Monitor and Hard X-ray Instrument

ASTROSAT-LAXPC:2-80 keV, 6000 sq cmWith All Sky Monitor, Soft/Hard X-ray Instruments, UVIT

Large Area X-ray Astronomical Observatories

USA Exp,2000 sq cmIXAE, 1200 sq cm

IXAE

LAXPC Characteristics Area : 6,000 - 7,500 cm2

Mass: 390 kg

Time Resolution: 10 µs, dead time 30-35 µs

Front-end and Processing Electronics: separate electronics for each detector

Data Storage: Onboard Memory 570 MB per Orbit

Detection Efficiency: 90-100 % upto 20 keV, ~40% upto 80 keV

Energy Resolution: 12-13% at 20-60 keV

Life Time: 3-10 Years, no Consumable

LAXPC: Effective Area

LAXPC: Energy Resolution

LAXPC: Complex Energy Response

• Energy response generation:Monte Carlo simulation / Ground calibration

Spectral Leakage in PCA and LAXPC

PCA LAXPC

Spectral Leakage in PCA

LAXPC Schematic

LAXPC: Complex Energy Response

PCA: Energy resolution of single events and escape events

ASTROSAT Ground Trace

LAXPC Advantages

Large effective area in hard X-ray band

Stable background

Low Spectral leakage

Wide energy band2-80 keV with LAXPC0.3-8 keV with SXT10-150 keV with CZT

Simultaneous, sensitive, multi-band UV/Optical observations

Only timing instrument it this time frame

Studies with LAXPCOnly Timing Instrument it this Time Frame

Hard X-ray Response

X-ray Pulsars (Pulsations, QPOs, Transient Nature, Orbital Evolutions)LMXBs (KHz and Low Frequency QPOs, Hard X-rays)Millisecond Accreting PulsarsRotation Powered Pulsars (Simultaneous Radio observations)BHCs (QPOs and variations in a wide range of time scale)

Pulsar Cyclotron Line Cluster Hard X-rays ?

Sky SurveySky Monitoring

Timing Studies

BH High Frequency QPOs (MAXI!)

CRSF with ASTROSAT LAXPC

Survey with Slew Data and Deep Survey

Radio X-ray Simultaneous Observations of

Millisecond Pulsars: Absolute Timing

ASTROSAT Launch

WindowOctober-December 2011

A Thomson X-ray polarimeter has been designed, developed and successfully tested.

Detectors, Front end electronics, Processing

Electronics, Collimators with flat top response

Test and calibration setup, Rotational stage

An Engineering Model is under fabrication

•Minimum Detectable Polarisation of 3% at 5σ (50 mCrab)

•No of sources: 50

Thomson X-ray Polarimeter for a small satellite mission

Unpolarised sourcePolarised source

Results

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