1P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow

Jem-Euso and its two satellites: Euso-Balloon and TA-Euso

"Doing Astronomy by looking downward"says Andrea Santangelo (but TA ?)

Actually, Jem-Euso is a two star system (Piergiorgio and Toshi) with many small satellite systems moving around in the big collaboration.

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 2

well done al dente not cooked

1 particle per km2 per century

requires a huge surface

CHARGED PARTICLE

ASTRONOMY

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 3

Method: fluorescence (full calorimetry as opposed to sampling)

Large field of view: ± 30° thanks to double sided spherical Fresnel lenses

At 400 km (ISS): 2 105 km2 (nadir mode) up to 106 km2 (tilted mode)

No need for stereo: 400 km >> shower length (TPC with a drift velocity = c)

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 4

Lenses: Japan + USPSF = 3 mm (PMT pixel = 2.88 x 2.88 mm)Material is PMMA and / or CYTOP (amorphous teflon)

Focal surface: Japan + France + Poland + Italy + Germany + Korea Made of 143 PDM (photo detector module)- 1 PDM = 9 EC (Elementary cell). Curved (R = 2.6 m)- 1 EC = 4 PMTs (smallest flat unit). One HV / EC- 1 PMT = 64 (8 x 8) pixels. Each pixel has photo-electron counting, and each group of 8 is connected to an integrator (KI) used for intense lights. Front end electronics are one ASIC / PMT. PMTs have BG3 filters (300-430 nm)

1 PDM = 6 x 6 PMTs, = 48 X 48 pixels = 24 x 24 km on ground (nadir). This size was chosen so that most showers are contained in one PDM. Level one trigger is made with a PDM board (FPGA). Then, the Cluster Control Board collects data for the 8 neigbouring PDMs.

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 5

This MAPMT with 64 anodes is what makes Jem-Euso really possible

We measured the pixel to pixel separation with a light beam of 100 µm resolution. Above is a scan showing this separation is less than our resolution. No dead space, perfect for a telescope focal surface!

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 6

PDM Frame

ASIC test board

Light source

Step Motor

64ch PMT

Light source

FPGA

Test of 1st level trigger

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 7

The altitude of the Xmax is crucial. It is given by the time difference between the max of the shower and the diffuse reflection of the Cerenkov light accompanying the shower. So, we have to know if there are clouds, and if yes at what altitude. This is the purpose of the Atmospheric Monitoring System (Yes, the acronym is what you think!), composed of a 10-12 µm IR camera (10-12 µm) provided by Spain and a 355 nm laser (Lidar but the receiver is Jem-Euso), shooting to a MEMS mirror aiming at the interesting showers. Lidar system in on the Swiss responsibility.

MEMS

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 8

New and very important: Russian group led by Mikhail is interested in the deployment mechanism, and the lid mechanism

Deployed

Stowed for transport in HTV rocket

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 9

Other house specialties: a) High voltage system

A normal voltage divider for 5000 PMTs would use 5 kW, and would not be strong enough when the light is above 50 times the background.We use instead voltage dividers (Cockroft Walton, CW) made by our friend Jacek Szabelski . There is one CW per EC (1987 ECs). They use a total of 60 W, and their impedance is perfect for a PMT (low at last dynodes, high at cathodes).

Light can increase dramatically (a lightning can be seen in daylight). We want to protect the PMTs AND measure these strong lights. When the light reaches 100 times the background, photoelectron counting does not work any more (pile-up), and the KI (integrator in front-end) tells the system to switch down only the voltage to the cathode, all other dynodes staying constant. The "gain" (or rather the collection efficiency) is reduced by 100, in less than 10 µs. This can repeat until the original gain of 106 goes down to 1.Then we can study large lights like elves, meteors, and even see if a large shower will be seen at the same spot than a lightning.

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 10

Other house specialties: b) Calibrations

We use the fact that we work mainly in single photo-electron counting. The difference in pC between the 1 spe peak and the pedestal (0 spe) is the gain. The surface of the 1 spe peak normalized to the number of sent photons is the PMT efficiency, and it can be measured through a patented method with a precision of 2%. This we will do before the flight for each of the 0.33 106 pixels of the focal surface.

During the flight, at each "day", the lid being closed, small integrating spheres will send light to the FS. The gain will be controlled in an absolute way, while the efficiency will be relative (but has been precisely measured in an absolute way before). We do something analog to control the lenses transparency.An absolute method which could be precise to some 10-20% is to open a small diaphragm in the lid (we are talking about that with our Russian members who make the Jem-Euso envelope) and look at the diffuse reflection on dense clouds (albedo of 80%) of the full moon.Another absolute method, precise to 20-30%, will be the use of special Xenon flashers specially made and operated on top of mountains or on high altitude NASA planes by our American colleagues.

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 11

Integrating sphere: perfect splitter NIST photodiode accurate to 1.5%

LED

Collimator: two 1 mm holes separated by 20 mm

PMT andvoltagedivider

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 12

Who is doing what?

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 13

Main program: cosmic ray showersand horizontal neutrinos

Secondary program:TLEs and meteors

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 14

Programmatics (1)

• Status at ESA: JEM-EUSO is being studied (since 2010) as a project of the ELIPS program. ESA acts toward a coordinated interagency effort. This has been very clearly confirmed by ESA on many occasions: recently with a letter sent to A. Olinto.

• Status at ROSCOSOMOS: Tsniimash (Roscosmos ISS) has expressed a clear interest in pursuing a wider participation of Russia in JEM-EUSO; Prof. Panasyuk has presented JEM-EUSO in January to and has obtained the endorsement of the STEC Committee. The Russian team is working on the procedure for the approval of a large-scale participation.

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 15

Programmatics (2)• Status at NASA: US proposal to SALMON AO (2011) was not

selected. ISS resources are the key item. New proposal to the APRA program has been submitted, asking both resources for the EUSO Balloon and for the main mission. A new stronger team is emerging in the US (with Angela).

• Status at JAXA: They encourage the participation of ROSCOSMOS but still consider NASA an essential partner. (Japan manages its participation to the ISS via NASA.) Collaboration with TA is very important.

• In the countries different level of funds: EUSO Balloon and TA-EUSO running at full speed, in parallel phase A study of the main mission.

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 16

EXPECTED EXPOSURE

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 17

And now, the two main satellites: TA-Euso and Euso-Balloon1) TA-EUSO

Tests and calibration at Telescope Array site, Utah

• Installation foreseen in winter 2012

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 18

Cross-calibration tests at Telescope Array site, Utah • Collaboration with ICRR, Institute of Cosmic rays, Tokyo University, Kashiwa

campus Installation winter 2012

• Main purpose: calibration using scaled telescope• Cross calibration with TA FD. TA-Euso resolution 5 times TA FD.a) When lidar or electron beam shoots, store the data to have an absolute

calibration.b) Take few showers in coincidence with TA. c) repeat the game in Auger. Cross-calibration of the system in Auger and TA

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 19

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 20

Installation for second week of november

Extremely important in the Japanse Cosmic Ray community

Bi-weekly meetings with TASkype conferencesLocation surveyLogistics under discussion

Cost sharing.

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 21

TA FD(Fluorescence

detector)

ELS: Electron Light Source

TA-EUSO location

TA site, UTAH, Black Mesa

PDM detector

LASER Team Size (mm)

Lenses

PDM detector block

Electronics block

Set on ground inside a modified Chinese container

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 22

2) EUSO-BALLOON

In 2009, Peter von Ballmoos group at IRAP (Toulouse, a few hundred meters from the french Space Agency CNES), decided to join the french Jem-Euso teams: APC and LAL.

He is a renowned balloon physicist, and it was proposed to CNES to make a kind of Jem-Euso pathfinder: Euso-Balloon. It was accepted by CNES exactly one year ago.

The idea is to use a PDM (6 x 6 PMTs, the basic Jem-Euso brick), with simple 1 m x 1 m square Fresnel lenses (same that TA-Euso) for the following goals:

- Test of electronics in a more severe environment than Jem-Euso: 3 mbar at 40 km altitude, where the Paschen effect is strongest: where, in vacuum 0.5 mm is enough to insulate 1000 V, 20 mm are required at 3 mbar. Here potting is mandatory everywhere HV is involved.

- Measure the light background with pixels similar to Jem-Euso (up to now, all balloons had no optics). It is more or less well known as the reflections of stars on ground plus the Airglow layer at about 100 km altitude.

- see a shower from space (we can see about one per night above 1018 eV)

This instrument is then very similar to TA-Euso, but two big exceptions: no potting, and good accessibility in TA-Euso

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 23

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 24

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 25

Optical system for balloon

• Three Fresnel lens • 1 square meter• 12o field of view

RFS = 2.6 m

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 26

JEM-EUSO Balloon – The CNES Steering committee has approved the

recommendation – On the 28 of February we have officially entered

phase B– Decision for implementation most likely in July 2012

CNES Decision First launch in Spring 2014 (from Kiruna or Canada)

Try to deliver the instrument mid – 2013.

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 2740cm PrototypeCherenkov Observation

with 40cm in Japan

40 cm Prototype Manufactured at RIKENand installed at Akeno, AGASA site (2001)

40cm Test at UAH

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 28

Finally, UFFO, a Russian-Korean (both teams in Jem-Euso) project, to be launched together with TUS, uses also a PDM but the pixels are covered with inorganic scintillators to detect gamma-rays in the range 10-1000 keV.

PDM

Coded mask

MEMS

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 29

This short diaporama is dedicated to the memory of our pioneer,

Yoshi Takahashi, who believed that humor is not incompatible with science.

This is true also for many peoples in this audience.

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 30

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 31

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 32

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 33

P. Gorodetzky for the Jem_Euso collaboration ECRS 2012, July 3 to 7, Moscow State University, Moscow 34