Elisabete de Gouveia Dal Pino (IAG-USP, Brazil)

On behalf of the CTA Collaboration

FAPESP Workshop

March, 2015

Thanks to W. Hoffmann, B. Rudak, E.Moulin, A. Zech, D. Mazim, J. Hinton, D. Torres

Unveiling the Gamma Ray

Universe

tevcat.uchicago.edu/

Supernovae

Pulsar wind neb.

Stellar clusters,…

Binary systems

Unidentified

AGN

Starburst-Gal.

TeV sky today (144 sources, 49 extragalactic)

po gg

p± m

±n

p + nucleus p +X

Image accelerators with gamma rays

Spectraand flux reflect

those of acc. particles

SEEING COSMIC ACCELERATORS

e+, e- :

IC, SSC -> g-ray photons

Detecting very high energy gamma rays:Cherenkov telescopes

Cherenkov Image

Cherenkov “light pool”on the ground:area ~105 m2

dormant nowH.E.S.S.

50 GeV to ∼ 50 TeV, collecting area ∼ 105m2,

∼ 4º FoV, angular res. ~ 0.1º

(TeV)

Key design goals: 10-fold increased sensitivity at TeV energies 10-fold increased effective energy coverage Larger field of view for surveys Improved angular resolution Full sky coverage: and array in each

hemisphere

CTA: What one can (hopefully) afford

Energies down to 20 GeV Cosmology++

Rapid Slewing20 seconds

transients

Energy Resolution≈10% lines,

features

Sensitivity & Collection

Area×10 all topics

Field of View≈8° surveys,

extended objects

Angular Resolution

Few arcminute morphology

Energies up to 300 TeV Pevatrons

REQUIREMENTS & DRIVERS

Core-energy array:23 x 12 m tel. (MST)Davies-Cotton reflector

- FOV: 7-8 degreesmCrab sensitivityin the 100 GeV–10 TeVdomain

Low-energy section:4 x 23 m tel. (LST)- Parabolic reflector- FOV: 4-5 degreesenergy thresholdof some 10 GeV High-energy section:

70 x 5-6 m tel. (SST)Davies-Cotton reflector(or Schwarzschild-Couder)- FOV: ~10 degrees10 km2 area at multi-TeV energies

(one) possible configurationSouthern 100 M€ Array (2006 costs)

Sensitivity (in units of Crab flux)for detection in each 0.2-decade energy band

LST

MST

SST

background andsystematics limited

background limited

rate (=area) limited

dark matterSignatures of EBL,

IGMF, LIV

ANGULAR

RESOLUTION

CTA SCIENCE CASE

Theme 1: Cosmic Particle Acceleration How and where are particles accelerated?

How do they propagate?

What is their impact on the environment?

Theme 2: Probing Extreme Environments Processes close to neutron stars and black holes?

Processes in relativistic jets, winds and explosions?

Exploring cosmic voids

Theme 3: Physics Frontiers – beyond the SM What is the nature of Dark Matter? How is it distributed?

Is the speed of light a constant for high energy photons?

Do axion-like particles exist?

EBL and IGMF…

EXAMPLE: GALACTIC PLANE SURVEY

H.E.S.S.

CTA, for same exposure

expect ~1000 detected sources

CTA

Current GalacticVHE sources (with distance estimates)

HESS

CTA

REACH

CTA VERSUS FERMI – TRANSIENT

SOURCES

Hinton & Funk

DARK MATTER ANNIHILATION

Canonical

cross section

Complex, structured VHE source (BH)

Gas clouds illuminated by Pevatron?

Dark matter halo emission?

Launch of Fermi bubbles?

GALACTIC CENTER REGION

5 sigma contours

CTA TELESCOPES

23 m diameter

389 m2 dish area

28 m focal length

1.5 m mirror facets

4.5o field of view

0.1o pixels

Camera ∅ over 2 m

Carbon-fibre structure

for 20 s positioning

Active mirror control

4 LSTs on South site

4 LSTs on North site

Prototype = 1st telescope

LARGE

TELESCOPE

(LST)

LST FULL PROTOTYPE

Will be constructed on La

Palma, starting in 2015

Elevation

drive

prototype

Dish structure

prototype

MEDIUM-SIZED 12 M TELESCOPEOPTIMIZED FOR THE 100 GEV TO ~10 TEV RANGE

100 m2 dish area

16 m focal length

1.2 m mirror facets

8o field of view

~2000 x 0.18o pixels

25 MSTs on South site

15 MSTs on North site

Berlin

MST prototype

operational

PHOTOMULTIPLIER CAMERAS

Recording signal waveform for “interesting” (triggered) images

Options:

Capacitor pipeline + analog trigger + (identical) “drawers”

NectarCam (Pixel cluster prototypes operational)

LSTCam (Pixel cluster prototypes operational)

Flash-ADC + digital trigger + rack-based electronics

Flashcam (144 pixel prototype operational)

SST - OPTIMIZED FOR THE RANGE ABOVE 10 TEV

SINGLE MIRROR SSTPROTOTYPE INAUGURATION JUNE 2

DUAL-MIRROR TELESCOPES

Vassiliev, Fegan, Brousseau

Astropart.Phys.28:10-27,2007

Reduced plate scale

Reduced psf

Uniform psf across f.o.v.

➜ Cost-effective small

telescopes with compact

sensors (SST-2M)

➜ Higher-performance

telescopes with small pixels

(SCT)

SST - OPTIMIZED FOR THE RANGE ABOVE 10 TEV

DUAL MIRROR ASTRI SSTPROTOTYPE INAUGURATION SEPTEMBER 24

ASTRI PROTOTYPE INAUGURATION

September 24th, 2014

Sierra la Nave Obs., Catania

ASTRI-CTA SST-2M PROTOTYPE

ASTRI CAMERA

The ASTRI Mini-Array: CTA precursor

The goal is the deployment and operation

of the mini-array with 9 SST-2M

telescopes at the CTA south site

Italy

Brasil

South

Africa

BRAZILIAN FUNDING FOR ASTRI-

CTA-MINI-ARRAY

Fundacao de Amparo `a Pesquisa do Estado de Sao Paulo

1.5 MEuro for building 3 SST-2M telescopes of the Mini-Array

IAG-USP

University of Sao Paulo

Sao Carlos

Sao Paulo

Rio de Janeiro

Universidade de Sao Paulo

Instituto de Astronomia, Geofisica e Ciencias Atmosfericas

Universidade Federal do Rio

Centro Brasileiro Pesquisas FisicasVitor de Souza

Carlos Todeiro Peixoto

Gustavo Rojas (UFSCar)

Ivone Albuquerque (IFUSP)

Ulisses Barres de Almeida

Ronald Cintra Shellard

Edivaldo M. Santos

Joao Torres MelloInstituto de Fisica de Sao Carlos

Elisabete de Gouveia Dal Pino

Rodrigo Nemmen

Grzegorz Koval

Claudio Melioli

Reinaldo Santos-Lima

Chandra Singh

Renato Gimenes (Eng.)

Carlos Firmino (Eng.)

Made in

Brazil

CTA Mini-Array

MST support

LST support

Argentina, Armenia, Austria, Brazil, Bulgaria, Czech Republic, Croatia, Finland,

France, Germany, Greece, India, Italy, Ireland, Japan, Namibia, Netherlands,

Norway, Poland, Slovenia, Spain, South Africa, Sweden, Switzerland, UK, USA

CTA MEMBERS: 28 COUNTRIES>800 SCIENTISTS AND ENGINEERS FROM >100

INSTITUTIONS

SITE CANDIDATES

+30

-30

Warning: map not quite accurate

two sites to cover full sky

at 20o-30o N, S

Critical

Design

Review

Site

Decision(s)

Design generic site

infrastructure

Design site-

specific

infrastructure

Implement site infrastructure

Site characterisationDetailed site

char., surveys

Continued monitoring of environmental and

atmospheric conditions

Telescope design

and prototyping

Produce Pre-Production

telescopes

Deploy and operate

Pre-Production telescopes

Final design

mods.

Mass-produce and deploy

telescopes

2015 2016 2017

Production

Readiness

Reviews

2018

Founding Decision

Pre-Production

Readiness Reviews

CTA SCIENCE

In-depth understanding

of known objects and

their mechanisms

Expected discoveries

of new object classes

The fun part:

Things we haven’t thought of ?

PHOTON PROPAGATION: AXION LIMITS

Axion conversion ??

De Angelis et al.arXiv:0707.2695,0707.4312

Sanchez-Conde et al.,arXiv:0905.3270

M. Meyer et al.arXiv:1302.1208

Increased transparency of Universe Modulation of spectra

In neV Axion mass range comparable toor better than dedicated experiments

Pg➝g

e.g. H.E.S.S. arXiv:1311.3148

PHOTON PROPAGATION: LI VIOLATION

g

HESS, arXiv:1101.3650arXiv:0810.3475

Velocity dispersion across TeV energy rangeless than ~20 s for ~109 yr travel ⋍ 10-15

➜ LIV mass scale > 2.1018 GeV (~E), 6.1010 GeV (~E2)

EarthAGN

A DIFFERENT BEAST:

OBSERVATORY

CTAObservatory

CTA Observatory users

CTA Consortium

Observation

proposals

Data

Key Science Projects

Data from Key Science Projects

“Gamma ray astronomy traces the energy skeleton of the Universe”

How do cosmic particle accelerators work?

Do do particles propagate?

Do do particles influence their cosmic environment?

ASTRI DUAL MIRROR CONCEPT

FROM CURRENT ARRAYS TO CTA

light pool radius

R ≈100-150 m

≈ typical telescope spacing

Sweet spot for

best triggering

and reconstruction:

most showers miss it!

large detection area

more images per shower

lower trigger threshold

SPECTRA OF SUPERNOVA REMNANTS

( from S. Funk)

No Pevatron yet! Cas A

(SN IIb)

RX J1713.7

(SN II/Ib ?)