a tigre on the moon timing italian gamma ray experiment

A TIGRE on the Moon Timing Italian Gamma Ray Experiment

E. Costa, Y. Evangelista, M. Feroci, M. Rapisarda(*), P. SoffittaINAF – IASF Rome

(*) ENEA Frascati

P. Battaglia, L. Pagan ALCATEL ALENIA SPACE - ITALIA, Vimodrone

TIGRE TeamIASF Rome

Observation of the Universe from the Moon Frascati – 7 May 2007

2

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

TIGRE TeamIASF Rome


3

Mid- and Near-future observational advancements in X-ray Astronomy are expected in the field of:– High resolution spectroscopyHigh resolution spectroscopy (e.g., Con-X, XEUS)

– Hard X-raysHard X-rays (e.g., Simbol-X, NEXT)

Not much is expected for TimingTiming, where significant improvements require passing from the current (RXTE PCA) 0.5 m2 to collecting areas in the range of 50-100 m2.

The Science Scenario

TIGRE TeamIASF Rome


4

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)

1.1. Quasi-Periodic Oscillations in Galactic X-ray Quasi-Periodic Oscillations in Galactic X-ray BinariesBinaries

Why a 100 m2-class Experiment?

GRBsGRBs: 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.

MagnetarsMagnetars: transient ~30-100 Hz QPOs have been detected for the brightest flares, most likely originated by the seismic motions of the compact star.

2. 2. High Resolution Timing of Bursts and Flares fromHigh Resolution Timing of Bursts and Flares from Gamma Ray Bursters and MagnetarsGamma Ray Bursters and Magnetars

3.3. Survey of X-ray PulsarsSurvey of X-ray PulsarsThe 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

4.4. and then Flares from Black-hole candidates, type-I and then Flares from Black-hole candidates, type-I bursters, INSs, bursting pulsar, rapid burster, bursters, INSs, bursting pulsar, rapid burster, supergiant fast X-ray transients, RRATs, ….supergiant fast X-ray transients, RRATs, ….

TIGRE TeamIASF Rome


5

TIGRE in words: the AssemblyThree interchangeable operative modes:

A)A) Open fieldOpen field of view for unpredictable events (e.g., GRBs, SGRs, ..) and Survey of Pulsars

B)B) Slit collimatedSlit collimated for gross localization

C)C) CCodedoded MaskMask (collimatedcollimated) for Source Localization and Monitoring

Alto-azimuthalAlto-azimuthal orientation capability.

ModularityModularity and independence of modules (or sets of modules), for operative mode, orientation and power supply.

TIGRE TeamIASF Rome


6

TIGRE in words: the Experiment

ModularModular

Favourable (Area) / (Read-out electronics) ratio

Energy Range: 1-10/20 keV,

Good Position Resolution (0.1-3 mm),

Good Energy Resolution (<1 keV)

Current detector choice: Silicon Drift DetectorsSilicon Drift Detectors, possibly in their Controlled Drift DetectorControlled Drift Detector configuration

TIGRE TeamIASF Rome


7

TIGRE in numbers (1)

TIGRE TeamIASF Rome


8

TIGRE in numbers (2)

TIGRE TeamIASF Rome


9

TIGRE in images: our view

TIGRE TeamIASF Rome


10

TIGRE Operating Modes

Silicon detector

Slit CollimatorSlit Collimator

Orthogonal Transit for gross localization of sources

Parallel Transit to reduce background

MaskMask: for fine localization of sourcesOpen SkyOpen Sky for

Unknown Pulsars or Bursting events

TIGRE TeamIASF Rome


11

The Silicon Drift Detector (SDD)

The collecting anode capacitance is

very small (~ 0.1 pF) and independent

from the device area

very low noise readout

Energy Range: 1-30 keV

Active area 10 mm2

Si thickness 300 mm

JFET embedded

E threshold 0.6 keV

E resolution @ 20°C 5% FWHM @5.9 keV(0.5 sec sh. time) 0.9% FWHM @ 60 keV

Noise (ENC) 45 e- rms @ 20°

241Am55Fe

(C. Labanti et al., IASF-Bo)

(Gatti & Rehak 1984)

TIGRE TeamIASF Rome


12

The Controlled Drift Detector

“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)

Developed at INFN-Milano / Politecnico di Milano (A. Castoldi, E. Gatti, C. Guazzoni, L. Struder, et al., 2001+).

TIGRE TeamIASF Rome


13

TIGRE in images: seen from AAS-IDetectors

ArraySlit Collimator

Mask Collimator

Service Module

Solar Array

Star Sensor

TIGRE TeamIASF Rome


14

Observation Modes

Open Field Slit or Mask Collimator

TIGRE TeamIASF Rome


15

Alto-Azimuthal Orientation

North

South

TIGRE TeamIASF Rome


16

Independent Operation of Adjustable Sets of Modules

TIGRE TeamIASF Rome


17

Launch and Deployment (AAS-I)

2060 mm

1590 mm

The release mechanism could be spring-loaded

with pyro-bolts.

TIGRE TeamIASF Rome


18

Multi-Module Communication

Large antenna

module

module

module

module

module

module

TIGRE TeamIASF Rome


19

Mass Budget (AAS-I) Q.ty Unit mass [kg] total [kg] 30% contingency [kg]

CDD 49 0.01 0.35 0.46

FE electr. 49 0.10 5.00 6.50 FE radiator 1 0.16 0.16 0.21

Detector structure 1 39.20 39.20 50.96

Slit collimator 1 47.00 47.00 61.10 Mask collimator 1 3.60 3.60 4.68

Collimator housing 2 28.70 57.40 74.62

Star sensor 1 3.00 3.00 3.90 motor 4 2.50 10.00 13.00

Shaft+Gear box 1 2.25 2.25 2.93

Science elect. Box 2 6.87 13.74 17.86 Bus elect. Box 2 6.60 13.20 17.16

front panel 2 0.72 1.44 1.87

Lateral panel 2 0.74 1.48 1.92 Shear panel 2 0.69 1.38 1.79

Top panel 1 1.87 1.87 2.43

service module str. 1 2.10 2.10 2.73 service module top panel 1 0.72 0.72 0.94

Main radiator 2 3.20 6.40 8.32

Battery pack 4 100.00 400.00 520.00 Ground baseplate 1 22.10 22.10 28.73

Antennas 1 1.20 1.20 1.56

Solar array 2 33.30 66.60 86.58 Clamp panel 2 28.70 57.40 74.62

TOTAL [kg] 754.39 984.87

TIGRE TeamIASF Rome


20

Power Budget (AAS-I)

[W] CDD 49

Eletctronics 50 5 motor 15

star sensor 10

panels 5 antenna 0.5

FE heaters 24.8

DC/DC 31 TOTAL [W] 185.3

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.

TIGRE TeamIASF Rome


21

… fly me to the moon …

♬♬ ♬♬

♬♬

a tigre on the moon timing italian gamma ray experiment

Documents