Vincent Van Gogh, “The starry night”

Extreme Universe Space Observatory

An Innovative Space Mission doing astronomy by looking downward from the Space Station at the Earth Atmosphere

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

hadron collisions: large energy density (1)

Classical hadron interaction (E The reaction is fast.

p < 10 18 eV) A large part of the energy goes into the leading particle (often the same as projectile).

At energy density > 3 MeV/fm 3 (E p > 10 18 eV) thermalisation can occur.

Same basic phenomena than Quark-Gluon-Plasma (deconfinement ) The reaction is slow.

No more leading particle. The energy goes into transverse energy (E T increases).

Fast interaction (leading particle)

Basic illustration (fluo vs ground?)

Slow interaction (thermalisation) Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Disoriented Chiral Condensate (DCC) (Baked Alaska); a theory by J.D. Bjorken (1)

Hadron-hadron collisions with cms energies where there is an especially large (no jets) transverse energy release. The high-multiplicity, high E T collision debris will expand outward the collision region at the speed of light for a few fermi before decoupling in real hadrons.

Hadrons Hot Shell   Incident hadrons Disoriented Chiral Condensate (a) (b) (c) At intermediate times, we have a hot thin shell with a relatively colder interior which will relax to something akin a vacuum. This vacuum is almost degenerate owing to the chiral symmetry, which is spontaneously broken.

This vacuum will radiate its pionic orientation, which is the observable of interest. So, if the deflection of the vacuum is in the p 0 direction, all condensate will be p 0 ’s (anti-Centauro) and if orthogonal, all pions will be charged (Centauro). These pions, emitted from a large volume, have a low p T - J. Bjorken

Results and perspective in particle physics

. Rencontres de la vallée d’Aoste. M. Greco editor, 1993 - G. Amelina-Camelia, J.D. Bjorken and S.E. Larsson

Pion production from baked-Alaska disoriented chiral condensate

; Phys Rev D 56(1997)6942 Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Disoriented Chiral Condensate (DCC) (Baked Alaska); a theory by J.D. Bjorken (2)

 Basically: assuming that the event-by event deviation of the quark condensate from its usual orientation, one finds that the distribution

P(f)

of the neutral fraction

dP df

 1

N dN df

 2 1

f f



N

at large p

N

0 

tot N N

p p 0  

N

p  

N N

p

tot

0 is given by Most notably, this implies that for Disoriented Chiral Condensate, the probability of finding extreme values of

f

is very different from ordinary pion production (which is given by a binomial distribution), in which the fluctuations are expected to be peaked at

f

= 1/3 and fall exponentially away from the peak.

1 binomial distribution 0,1 DCC

This JACEE event (p interaction in calorimeter) is evidence for “texture” in the lego plot 360 270 photons charged particles 180 JACEE 4LIIG-27 S E g = 15.4 TeV proton primary

DCC distribution 0,01

90

0,001 Binomial

photon

0,0001

threshold

f f

10 -5 0 2 4 N 6 8 10

The most favorable are p-nucleus reactions (sizable matter to traverse, but still a thin hot shell.

So, how do fluo and ground measurements behave in these conditions?

0 3 5  7 Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004 9

Calorimetry vs pattern

If the ratio of the electrons to the charged pions in a shower stays constant, its repartition in rapidity bins could very well be not uniform. This is not too important when looking at the fluorescence, for it is a calorimetric measurement. (and furthermore the number of electrons at the shower max is extremely stable and proportional to energy), even if the electrons repartition in  is not uniform.

However, if one looks at the pattern of particles hitting the ground (

the ratio of particles outside a circle to particles inside

), the result will not be so robust, on an event-by event showers with the same energy.

The high E T of the first hadronic collisions will put more particles not what seems to be observed?

outside

, and is it Fluorescence measurements are then probably more precise in energy determination.

Angular resolution is also more precise for the statistics in photo-electrons (fluo) are better than those on ground stations (at least for muons which are alone for inclined showers).

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

How to check (if a problem exists)

The crucial plot.

A piece of cake for AUGER!

And, why wait?

K.H. Kampert just showed it!

(1 st preliminary hybrid event shown in Florence, now many more points)

Deconfinement ?

(or something else) 0. 01 0.1

1 Ground e nergy (10 20 eV)

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

10

Has the GZK suppression been discovered?

J.N. Bahcall and E. Waxman hep-ph/0206217 v5 27 Feb 2003

In this important paper, Bahcall and Waxman claim that there is no need for exotic new physics to account for the observed events with energies greater than 10 20 eV, except for the AGASA data.

They adjust individually the absolute energy calibrations of the various experiments (with fractional E shifts all well within published systematic errors in E) so that they agree @ 10 19 eV, and find that the agreement is excellent from 10 18 to 5x10 19 eV. -------> Envelope of EUSO data in five years if No GZK ------------------------------------------- Energy scale Expected Observed ------------------------------------------- Fly’s Eye 34 4 AGASA 40 6 Yakutsk 46 6 A fit with their “Extra-Galactic + Galactic and No GZK (an extrapolation of the E 6x10 18 to 4x10 19 -2.75

energy spectrum in the precise region eV)” is shown on the left.

The table compares the events above 10 20 eV and shows a strong deficit (>5

observed.

 ) of observed events.

Hence, this is a strong suggestion that the GZK cutoff has been

But this is based ONLY in the precise data at “low” energy

---> we need precise data from 5x10 19 to 10 21 eV.

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

SPACE vs GROUND (1)

ESA's Integral detects closest cosmic gamma-ray burst 5 August 2004

A gamma-ray burst detected by ESA's Integral gamma-ray observatory on 3 December 2003 has been thoroughly studied for months by an armada of space and ground-based observatories.

Astronomers have now concluded that this event, called GRB 031203, is the closest cosmic gamma-ray burst on record, but also the faintest .

This also suggests that an entire population of sub-energetic gamma-ray bursts has so far gone unnoticed...

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

SPACE vs GROUND (2) AMS p

AMS shuttle

He

Parametrization F (R) = F 0 R g with R (rigidity) in GV

NO PRECISION… NO HOPE!

AMS ISS Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

What EUSO looks like

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

High statistics

Target mass: 10 12 - 10 13 tons

SIZES

Fixed Moving Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

EUSO: Who does what ?

Ground Segment : Portugal LIDAR : Switzerland - Italy Electronics : France - Italy Analog - Digital Mechanics : France - Italy Photo-detector : Japan ≈ 200 000 pixels Optics : USA f ≈ 2m Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

US Optics I

Quic kTime™ et un décompress eur TIFF (non compress é) sont requis pour v is ionner c ette image.

The ISS is known to move quite a lot.

QuickTime™ et un décompresseur TIFF (non compressé) sont requis pour v isionner cette image.

A a

lens

(refraction) tilt produces a smaller movement of the image than

mirror

(reflection) tilt.

QuickTime™ et un décompresseur TIFF (non compressé) sont requis pour visionner cette image.

QuickTime™ et un décompresseur TIFF (non compressé) sont requis pour visionner cett e image.

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

CYTOP?

French activities LPSC (Grenoble) & APC/PCC (Collège de France)

Simulations - ESAF Atmosphere Analysis, Lidar Communication Outreach F.Vannucci

Analog electronics Front End QuickTime™ et un décom press eur TIFF (non com press é) sont requis pour visionner cette image.

Thermal conductivity of FSA (Summer, 6 m 2 , 850/200W) Mechanics and thermal study of the focal surface Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Germany (Munich) calibrations

And elsewhere…

Italy-Alenia ESA Japan USA

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Acceptance and counting rates I

Shower, detector and trigger simulation: Shower production : Corsika -> parameterization GIL Photons production : Fluorescence (Kakimoto et al.) and Cerenkov Atmosphere transport Optics : Rayleigh, Mie, Ozone (LOWTRAN7) : Transfers and aberrations Photo-detectors Trigger : Filters and quantum efficiency : Thresholds and persistence (N thre , N pers ) Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Acceptance and counting rates II

The absolute threshold is anchored by ∆  and the detection efficiency.

The trigger performances determine the acceptance evolution versus energy.

The asymptotic efficiency will be determined by the cloud coverage. Efficiency times the power -2.7 law Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Clouds effects I

The cloud coverage will play an important role : • Eventually mask part of the shower (S max ), • Increase the Cerenkov light reflection; The cloud coverage is given by the ISCCP database : 280x280 km

2

pixel size: Longitude, latitude, every 3 hours --> altitude, albedo, cloud fraction.

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Clouds effects II

NO CLOUDS CLOUDS Clouds reduce efficiency from ≈ 86%  ≈ 53% Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Clouds effects versus shower energy

E = 5x10

19

eV E = 1x10

20

eV E = 5x10

20

eV Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Duty cycle

Duty cycle (time fraction usable for measurements) depends on the "photon background" : Without moon, this background is estimated (measured) to 300 ph/m

2

/nsec/sr It originates from the stars light and to the "Airglow" It does not depend critically on the cloud coverage (≈ +20%) Moonlight will limit the duty cycle.

• for12.8% of the time, moon is under horizon, • for 18% light increase is insignificant, • for 25% light increase < 100 ph/m 2 /nsec/sr.

To that, too short nights have to be removed (<10% of them).

Euso has a warranty of a 3 years effective measurement time (and, see this talk end, if JAXA HTV is used, there is no return).

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

A possible measurement … (duty cycle 12%)

Super-GZK, in the French terminology, really means: No GZK Courtesy of AGASA N evt GZK (E >10 20 eV) >100 Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Angular resolution

Precise showers analysis will be made on an “event by event” basis: each shower will get errors specifically depending of the observation conditions.

As of today, only a statistical error estimation is considered.

Angular resolution : ∆

q

< 1° if

q

shower > 60°

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Energy resolution, errors I

“End-to-End” simulation software allow to estimate errors (statistical and systematical) associated to all parameters: Fluorescence, quantum effic., optics transmission, temperature, density, atmospheric transmission, angle,… Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Energy resolution, errors II



dN pe



dL E



E c X rad



N e

(

X

)

dX N e

(

X

) 4 p

R

2

S lens



Y

(  ,

X

)

T atmos

(  ,

X

)

QE

(  ) 

filter

(  )

T lens

(  )

d



Nature

Missing energy E  e Method + (1 st Int. + Nb of p.e) e  fluorescence Atmospheric correction Optics + detector Temperature and Pressure Q shower (2°) Mass (p -Fe)

Total Error

5% 5% 10%+10% 20% -> 10% 15% 10% 5% 2% 5%

27%

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Horizontal showers and Neutrinos

• Shower

length

depends on the encountered density • 

Fluorescence

production (O 2 being a quencher) depends only on altitude (< 15km)

Shower width (∆T) will then depend only on altitude.

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Neutrinos and Hadrons showers

• The probability to observe an (≈ horizontal) hadronic shower with a maximum under 10 km is extremely weak.

• Instead, this probability is maximum for neutrinos.

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Neutrinos acceptance and boundary fluxes

EUSO total acceptance for neutrinos (interacting in atmosphere) is ≈ 0.15 x 10 km 2 .sr

Corresponding to a detection limit of J( E )*E 2 ≈ 70 eV cm -2 sr -1 For horizontal showers (>85°), a 15 times increase is to be foreseen.

Acceptance with identification Neutrino acceptance is low, but if fluxes are adequate, the observation of an horizontal shower, under 10 km, should be the hallmark of neutrinos.

The n t , interacting with the earth crust would have an acceptance x 10-100 For horizontal showers (no ground array), the ratio of EUSO to AUGER areas is 100, plus - shower length ≈ AUGER F ==> full shower never observed in its totality - EUSO scans the whole sky Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Ups and downs (and ups…) Situation until June 2004:

ESA: Science division is in charge. As we are phase A, they do not give money, but examine scientifically.

In France, IN2P3 pays for phase A (INFN in Italy…).

NASA: Code S (Science) is in charge. In phase B and get money. Will be reexamined at end of phase B. But will not go further phases alone.

JAXA: ISS division. Are in phase A, going to phase B, Riken paying. ESA ISS division (with Science div. Physicists) says EUSO passed phase A successfully.

June 04:

ESA Science directorate says no to phase B for AUGER and Shuttle reasons. Real reason is money.

A. Watson replies that AUGER first results will be in 05 and not 08 or 09. JAXA proposes their HTV to replace Shuttle.

ESA MSM (ISS) division offers to replace Science division.

August 20 2004

Director of Science division at ESA agrees that EUSO switches from his division to the MSM (ISS) division (keeping control however).

It looks like ASI (and CNES hopefully) finds this OK. Livio Scarsi is in Riken with ESA, NASA and JAXA.

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Japanese docks

JEM-EF

•JEM-EF in ISS

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Payload Interface/Resource

a. Power 3kW × 2ch (120VDC) 2 locations (EFU#1,#2) b. C&DH High rate data 8ch Video data 8ch Ethernet 7ch c. TCS Maximum Heat Transfer Total 10kW (plug the cooling liquid).

More power (3 kW instead of 1 kW) means:

- more computing, hence a local trigger based on continuity of pixels ==> threshold can go down to less than 1x10 19 eV (maybe even less, see Hank Crawford) - PMT bases with more current ==> better stability Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

EUSO-HTV revised configuration: description

FRGF (Focal Surface Module structure to be redesigned to support FRGF loads) Passive MCAS Passive FRAM for on-orbit attachment of LIDAR Radiator Batteries and Electronic Boxes HTV I/Fs (wheels and TSM) supported by EUSO P/L structure Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

HTV door problems

1750 m m Stop 2080 mm 1650 mm 2765 m m

HTV DOOR

30 cm free. If we add the 12 cm at the bottom, then we have 42 cm. Enough to accomodate LIDAR + fixations?

2695 m m

EUSO ENVELOPPE

300 mm for the lid Lens1 Bellows Lens2 Gain = 820 mm Gain =500 mm Gain = 850 mm

HTV

330 m m Foc surf 200 mm for electronics, boxes, etc.

12 cm free 2450 m m 2500 m m Cytop diffractive July 05 Scale = 1/20

Door EUSO horizontal in HTV (Alenia solution) EUSO vertical in HTV (CdF, Riken & UAH solution)

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

In the future

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004

Philippe Gorodetzky - EUSO collaboration PCC / APC - Collège de France XIII ISVHECRI Pylos, September 6-12, 2004