A%20TIGRE%20on%20the%20Moon%20Timing%20Italian%20Gamma%20Ray%20Experiment

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A TIGRE on the Moon Timing Italian Gamma Ray
Experiment
E. Costa, Y. Evangelista, M. Feroci, M.
Rapisarda(), P. Soffitta INAF IASF Rome ()
ENEA Frascati P. Battaglia, L. Pagan ALCATEL
ALENIA SPACE - ITALIA, Vimodrone
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The Lunar Scenario

• The Moon offers a wide and stable surface
• Large Area Long Duration
  Experiments
• The Moon rotates
• Wide Field and Transit Experiments
• Transportation to the Moon will limit size and
  weight
• Modular approach for multiple deliveries

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The Science Scenario

• Mid- and Near-future observational
  advancements in X-ray Astronomy are expected in
  the field of
• High resolution spectroscopy (e.g., Con-X, XEUS)
• Hard X-rays (e.g., Simbol-X, NEXT)
• Not much is expected for Timing, where
  significant improvements require passing from the
  current (RXTE PCA) 0.5 m2 to collecting areas in
  the range of 50-100 m2.

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Why a 100 m2-class Experiment?

1. Quasi-Periodic Oscillations in Galactic X-ray
   Binaries

2. High Resolution Timing of Bursts and Flares
from Gamma Ray Bursters and Magnetars
To observe individual cycles of QPO emission and
directly study the accretion of matter onto the
blak hole from the innermorst stable orbit of the
accretion disk, where the strong field gravity
operates and the motion of matter is directly
related to fundamental parameters of the system.
(see also ASI-INAF 2004 study on perspectives for
High Energy Astrophysics)
GRBs in both the Hypernova and Merging stars
models, in the very early phases (i.e., first
milliseconds) the orbiting matter is expected to
cause fast pulsations of the emission, possibly
the only chance to directly observe the
properties of the GRB inner engine and of the
parent objects. Magnetars transient 30-100 Hz
QPOs have been detected for the brightest flares,
most likely originated by the seismic motions of
the compact star.
3. Survey of X-ray Pulsars
The class of radio-quiet isolated neutron stars
(e.g., Geminga-like) is far less populated than
radio-loud pulsars (10 vs 1500). This
difference is not yet understood, whether it is
due to real quenching of the radio emission or it
is due to a transient nature. An unprecedently
deep X-ray pulsar survey will likely compensate
observational selection effects bring to the
discovery of several Geminga-like pulsars and
assess this issue, constraining pulsar models
4. and then Flares from Black-hole candidates,
type-I bursters, INSs, bursting pulsar, rapid
burster, supergiant fast X-ray transients, RRATs,
.
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TIGRE in words the Assembly

• Three interchangeable operative modes
• Open field of view for unpredictable events
  (e.g., GRBs, SGRs, ..) and Survey of Pulsars
• Slit collimated for gross localization
• Coded Mask (collimated) for Source Localization
  and Monitoring
• Alto-azimuthal orientation capability.
• Modularity and independence of modules (or sets
  of modules), for operative mode, orientation and
  power supply.

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TIGRE in words the Experiment

• Modular
• Favourable (Area) / (Read-out electronics) ratio
• Energy Range 1-10/20 keV,
• Good Position Resolution (0.1-3 mm),
• Good Energy Resolution (lt1 keV)
• Current detector choice Silicon Drift Detectors,
  possibly in their Controlled Drift
  Detector configuration

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TIGRE in numbers (1)
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TIGRE in numbers (2)
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TIGRE in images our view
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TIGRE Operating Modes
Slit Collimator
Parallel Transit to reduce background
Orthogonal Transit for gross localization of
sources
Mask for fine localization of sources
Silicon detector
Open Sky for Unknown Pulsars or Bursting events
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The Silicon Drift Detector (SDD)
(Gatti Rehak 1984)
241Am
55Fe
Energy Range 1-30 keV Active area 10 mm2
Si thickness 300 mm JFET embedded E
threshold 0.6 keV E resolution _at_ 20C 5 FWHM
_at_5.9 keV (0.5 msec sh. time) 0.9 FWHM _at_ 60
keV Noise (ENC) 45 e- rms _at_ 20
The collecting anode capacitance is very small (
0.1 pF) and independent from the device
area ? very low noise readout
(C. Labanti et al., IASF-Bo)
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The Controlled Drift Detector
Developed at INFN-Milano / Politecnico di Milano
(A. Castoldi, E. Gatti, C. Guazzoni, L. Struder,
et al., 2001).
Evolution of SDD multi-linear SDD detector
with longitudinal coordinate derived by charge
drift time (T0 from backside electrode). Noise
performance comparable to SDD, position
resolution 100 ?m, read-out electronics for
multi-linear SDD only (N vs N2), room temperature
operation. Effective low energy threshold and
single detector area to be assessed.
(A. Castoldi et al., 2003)
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TIGRE in images seen from AAS-I
Detectors Array
Slit Collimator
Mask Collimator
Star Sensor
Solar Array
Service Module
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Observation Modes
Open Field
Slit or Mask Collimator
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Alto-Azimuthal Orientation
North
South
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Independent Operation of
Adjustable Sets of Modules
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Launch and Deployment (AAS-I)
1590 mm
2060 mm
The release mechanism could be spring-loaded with
pyro-bolts.
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Multi-Module Communication
module
module
Large antenna
module
module
module
module
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Mass Budget (AAS-I)
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Power Budget (AAS-I)
This budget includes large solar arrays to
recharge batteries while the module is
operating. Batteries have been dimensioned to
give the needed power continuously for a period
of 14 days (336 hours). The FE heaters power
consumption has been considered in the night only
operational configuration.
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?
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fly me to the moon
?