Roberto BattistonUniversità and INFN Perugia

LNF March 22nd 2006

Technologies for microsatellites

Space is an opportunity to change system of reference…….

Leonides storm seen from spaceFe, 1 mm3 , 40 km/s , E = 0.5 J1 proton, E= 1020 ev = 16 J

Credits to P. Jenniskens (NASA/Ames, SETI Inst.)

……to see things from another perspective

Half a centuryafter the Sputnik and

the discovery of Van Allen Belts, space is fully maintain its

unique potential for discovery and surprises

THE ROUTE OF “INCREASED ACCURACY”

The sensitivity of the instrumentation and the technologies Have improved dramatically

The more we understand about the Cosmos the more we are challenged to build sophisticated instruments, to match the sensitivity scale set by the physics of the Universe at different Time and Space scales.

Very complex instruments have been deployed and even more sophisticated one are scheduled or dreamed

Edwin P. HubbleMount Wilson Mount Palomar

Hubble (1929) HST (1999)

km/s/Mpc5000 H km/s/Mpc700 H

Dominated by systematic errors! 10.z

NASA Beyond Einstein Program

Not only large facilities, however, have a discovery potential, like in

today HEP at accelerators

Clever, small experiments, using new or “first time used in space” technologies

continues to give rise to fantastic surprises like at the time of Van Allen

THE ROUTE OF “GETTING THERE FIRST”

Further progress o tog rr ysa a !

COSMIC RAYS

Baby EUSO

MULTIANODEPHOTOMULTIPLIER TUBE ASSEMBLYH7546

MEGSAT 1 e 2

CONTROLLER

COMUNICATION AND POWER INTERFACE

FRONT END

HIGH VOLTAGE POWER

SUPPLIES

AURORA CH.

BACKGROUND CH.

CONNECTION BOARD

405

325

330

AURORA ON MEGSAT-2

A. Monfardini1,2, R. Stalio1,2, P. Trampus2, R. Battiston3,4,

M. Menichelli4 , N.Mahne2, P. Mazzinghi5

1 University of Trieste; 2 Carso, Area Science Park, Trieste,

3 University of Perugia, 4 INFN, Perugia, 5 INOA, Firenze

Silicon PM

Fotografia di un wafer

Fotografia di un SiPM

Functional measurement set-up (1)

Preamplifier board: received from Pisa two stage preamplifier based on THRS4303 chip (high bandwidth: 1.8 GHz, fixed gain: 10 V/V) overall gain: theoretical 10x10x2/5 = 40, measured 42

Preamplifier

SiPM

Blue light LED (470 nm)

Faraday box

50

SiPM Signal Current pulse

IN

SiPM SignalVoltage pulse

THRS4303x10

THRS4303x10

150

100

50 OUT

SiPM amplified voltage pulse

Bias 33V (2V overvoltage)

One pixel dark count signals

Two pixels dark count signals

A1

A2= 2A1

Bias 34V (3V overvoltage)

One pixel dark count signals

A1’ > A1

A2’ = 2A1

’

Two pixels dark count signals

Dark count signals

Threshold(see next slide)

Recovery time: ~ 20ns

Rise time: ~ 1ns

1.E+02

1.E+03

1.E+04

1.E+05

1.E+06

1.E+07

0 50 100 150 200 250 300 350

threshold (mV)

dar

k ra

te (

Hz)

32 V

32.5 V 33 V

33.5 V 34 V

34.5 V 35 V

36 V

T = 23°C, Vbreakdown = 31 V

Dark count ratePlateau of one pixel dark count signals

Plateau of two pixels dark count signals

Single pixels dark count rate: our SiPMs: 5 MHz (5V overvoltage, T=23°C) Russian SiPMs: 2 MHz (5V overvoltage)

Russian SiPM from CPTAVbreakdown = 47 V

Gain

SiPM gain: linear variable with overvoltage in the range 5x105 2x106

Histogram of the signals area

Markers delimitating the integration zone of the signal

0.0E+00

5.0E+05

1.0E+06

1.5E+06

2.0E+06

2.5E+06

3.0E+06

0 1 2 3 4 5 6

Overvoltage [Vbias - Vbreakdown] (V)

On

e p

ixel

gai

n

gain - single pick area

Lineare (gain - single pick area)

Vbreakdown = 31V

Two pixels dark count signals

One pixeldark count signals

SiPM signals under pulsed lightVery preliminary and qualitatively results

BLUE pulsed light (470 nm)

SiPM sensible to the blue light

Dark count signals

Pisa measurements Very good resolution of single photoelectrons

Trigger

SiPM signal

RED pulsed light

N. Dinu (Irst)

DaSipm Bologna Group

As we have done for the PMT, we developed a Montecarlo model that allows us to simulate the SiPM behaviour. Even if the model is phenomenological and not physical the results reproduced the real mesuraments.These means that the SiPM behaviour is quite understood at least in his main characteristics.

G. Levi et al.

DaSipm Bologna Group

Scintillator

SiPMs + FE

future TOF counter

Beeing unsensible to magnetic field, SiPMs do not need light guides.Scintillators will be read through WLS fibers directly coupled to the SiPM.A first evaluation of weight saving is around 50-60kg, considering only the light guide and PMT.Lighter and simpler supporting structure and low voltage power supplies will increase this figures.

Light guide + PMT = 25 cm SiPM + FE = 2.5 cm

MEMS Space Telescope for UHECR Study

(MEMSTEL)

IL H. PARK (Ewha W. University, Seoul)

Research Center for MEMS Space Telescope

funded by Ministry of Science and Technology in Mar. 2006

Principle of MEMS Tracking Telescope

•Archimedes Mirror : Mirror Segments, Soldiers Operation

•Park’s Mirror : Micromirrors, VLSI Control

•Aberration free focusing & Wide FOV•Tracking capability

VLSI Micromirror

Photodetector

ObjectAir Shower

Micromirror & Circuits

Photodetctor

Prestudy 1-axis Analog Micromirror Design, Fabrication, Test

Electrostatic Comb-drive Actuator

Specification• 1-axis • Max angle: 4 degrees

at 100V  • Frequency: > 5 kHz • Cell size: 372 x 970

um2 • Micromirror size : 372

x 150 x 30 um3 • Comb size: 260 x 6 x

30 um3 • Torsion spring size :

120 x 3.5 x 30 um3

Design

Fab Test

Prestudy 2-axis Micromirror Fab. Simulation

Hidden comb drive actuator (1-axis at present, 2-axis under way)

2-axis Side comb drive actuator

Prestudy MEMS Tracking Simulation

Fresnel mirror

Incident angle = 20o

MEMS mirror

Incident angle = 20o

Micromirrorarray

Detector plane

Mirrorplane

Fresnel mirror

Incident angle = 0o

Analog Board

Digital Board

PMT or SiPM (1296 ch)

PMT Power Supply

NIR Detector

NIR Electronics

Micromirror Array

MEMS Telescope Payload Design

MEMSTEL ParametersMEMSTEL Payload parameters

Orbit height 400 km

Mirror diameter 1 m

Focal distance0.34 ~ 0.8 m

(variable)

No. of Photodetector Ch

1296

FOV 40 ~ 70o (variable)

Field resolution10 - 2.5 - 0.6 km

(variable)

Trigger latency 3 ~ 10 usec

Aperture 85,000 ~ 300,000

km2

Payload weight 20 kg

Power 20 Watt

Micromirror Parameters

Power/cell  < 0.1 μA

tilting angle5 ~ 10 degree

angle resolution

0.1 degree

Cell size

100x100 μm2 ~ 1000x1000 μm2

Rotation x, y axis

Fill factor 95 %

cost (for 4"wafer)

$1000

High Energy Quantum Optics: Compton Gamma Detectors

A stack of Si/CdTe strips/pixels

in a BGO well (10,000 ch)

Takahashi et al.SPIE 2003

Micro-particle detector

What’s next in the “NeXT” mission

Narrow FOV Compton Telescope(100 keV- 1 MeV)

• Extremely Low Background( High S/B ratio)• Capability of the polarization measurement

E1

E2

Quantum optics

Photoelectric effect and polarization (R. Bellazzini)

4

222

4

5

2

cos1

24

137cossin2

7

h

mcZro

The photoelectric effect is very sensitive to photon polarization

2cos

Projecting on the plane orthogonal to the

propagation direction…

8-layer PCB fan out to front end hybrid

Angle and amount of polarization is computed from the angular distribution of the photoelectron tracks

GEM: provides gas amplification and fast trigger

The detector

Readout plane: 512 pixels, 260 um pitch, 2.4 x 2.4 mm2 active area

The new detector!

• 2101 pixels (80 um pitch) comprehensive of preamplifier/shaper, S/H and routing (serial readout)• 200 electrons ENC• External trigger for parallel S/H on all channels• 200 us for complete readout• 100 uW/channel power consumption

Full custom ASIC (CMOS technology) directly used as a multi pixels readout electrode.

Reconstruction algorithms, data analysis

New reconstruction algorithms now under study:• Exploit higher moments of reconstructed charge distribution• Improve imaging capabilities• Enhance accuracy in angular reconstruction• Study the effect of cuts on polarimetric sensitivity.

GRAVITATION

A gravitationally Hyper sensitive experiment !

HYPER

Bose Enstein condensates

Interferometry: 109 atoms an unique wave function

Space Time fluctuation:getting to the Plank scale

by cold atoms interferometry

HYPER - precision cold atom interferometry in space

NEW HIGHLIGHTS IN ATOM OPTICSPARIS2001/2

1st BEC ON A CHIP

Highest gradients with minimum Currents

= Lower Magnetic Fields (Metrology)

= Lower Power (Transportable Microsensors)

Simpler Production

FUTURE EFFORTS

APPLYING THESE TECHNIQUES FOR FUNDAMENTAL PROBLEMS IN METROLOGY

Who can build a cheap micro/nano satellite ?

Universtities + Research Centers +Small Hightech industries

Best example: University of Surrey (UK)

Most impressive example : China DhF CAST

• PHD TOPICS WITHIN SSC • SMALL SATELLITE SAR • CHIPSAT • FORMATION FLYING . • COST-EFFECTIVE NAVIGATION AND RANGING FOR LUNAR AND INNER

PLANETS MISSIONS • IR SENSORS • HYPERSPECTRAL IMAGERY • SATELLITE AUTONOMY • MULTI_USER ACCESS TO SATELLITES • DEBRIS MITIGATION • RENDEZVOUS/DOCKING • LUNAR LANDER & MARTIAN HELICOPTERS

Additional benefits of this approach

• New way of doing “fundamental physics”• the most effective things that a small satellite can

do.• ways in which everyone can involve in space

science

Think of

Lower hurdles for easier access to space

Small but Smart and Quick

It is not easy to “involve in the field of Space Science”

Only many possibilities can encourage many players to take part in;

10cm x 10cm x 10cmCube Sat. (U. Tokyo)2003/June/30 LaunchCost < $ 100K (including launch)

Conclusion

• The universe is the current frontier for new exciting physics

• Space is a privileged reference frame to study the universe• Very large, powerful facilities will bring us to new

frontiers in knowledge• Small satellites, as intermediate steps to reach the most

ambitious goal set by major satellites, both testing new technologies and educating a new generation of laboratory oriented astroparticle physicsts

……and hopefully bringing us some big surprises