First Results from MAGICextras.springer.com/2006/978-1-4020-4351-2/Jenam/... · La Palma, Canary...
Transcript of First Results from MAGICextras.springer.com/2006/978-1-4020-4351-2/Jenam/... · La Palma, Canary...
First Results from MAGICthe Major Atmospheric Gamma-ray Imaging Cerenkov telescope
M.V. FonsecaUniversidad Complutense de Madrid
for the MAGIC Collaboration
JENAM 2004
EGRET- 100 MeV < Eγ < 10 GeV- A ~ 0.15 m2
> 270 sources (170 unidentified)
First Generation IACTs- Eγ > 300 GeV- A ~ 40000 m2
~ 18 sources
Something must happen inThe unknown energy range
10 GeV < Eγ < 300 GeV
The Gamma Ray Universe
Space detectors (GLAST 2007)Large field of viewSmall collection area (~1 m2)Energy sensitivity up to ~100 GeV
Ground detectors (ECO1000, MAGIC)Small field of viewLarge collection area (~104-105m2)Energy sensitivity from ~10 GeV
Large Cherenkov TelescopeOptimised for:
- low threshold: Eγ < 30 GeV - fast repositioning: tR < 30 s.
Many new technological elements
Cosmic Ray Detection Approaches
EnergyThresholdDown to30 GeV
A-Resolution: 0.2° @ 30 GeVdown to 0.1° > 100 GeV
E-Resolution: 30% @ 30 GeVdown to 15% > 100 GeV
3C2793C273
The “Big” Four
CANGAROO III(Australia & Japan)
Spring 20044 telescopes 10 meters Ø
Woomera, Australia
Windhoek, NamibiaHESS
(Germany & France)Summer 2002
4 ( 16) telescopes10 meters Ø
Roque delos Muchachos, Canary Islands
MAGICMAGIC(Germany, Italy & Spain)(Germany, Italy & Spain)
Winter 2002Winter 20021 telescope 17 meters Ø1 telescope 17 meters Ø
Montosa Canyon,Arizona
VERITAS(USA & England)
2005?7 telescopes10 meters Ø
Dark MatterDark Matter
PulsarsPulsars
GRBsGRBs
Quantum Gravity Quantum Gravity effectseffects
γγ--Ray HorizonRay Horizon
The MAGIC Physics Topics
SNRsSNRsAGNsAGNs
Diffuse Diffuse γγBckgrdBckgrd
Active Galactic Nuclei• Highest variability in
X-ray and γ rays• Multiwavelenght
campaigns necessary for source physics
• Closest to supermassive BH at Very High Energies
NGC 4261
Pulsars: Pulsar in Crab nebula• Rotating neutron star • Pulsed emission cutoff
10-50 GeV• Outer gap/
polar cap model ?• Continous TeV radiation
from shockfront
optical X-rayinfrared
radio
E.de Oña,next talk& R.Reyes poster 1.9
The Gamma Ray Horizon• High energy γ photons interact with γ of
the cosmic FIR to UV background by:
γHE γBKG e+e-
Attenuation• Cutoff in source spectrum
Knowledge of gamma ray horizon:Limits on cosmological parameters Cosmic star formation history
Lack of measurements
Cosmic Background light
• Origin of GRBs : Galactic or Cosmological
• Theoretical Emission Models:- Standard fireball, Internal & External Shock
• Multiwavelength study
• GeV studies possible if:– fast repositioning ~10 s– low E threshold ~30 GeV
Pulse Duration
“short”
“long”
Gamma Ray BurstsUniformity
10 s
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
Mean Repositioning Time ~ 20 s
Point ANY place in the sky in ~30 s
What do we need to study GRBs? Telescope Fast Movement
~100 Physicists17 Institutes11 Countries
MPI Munich, GermanyU. Würzburg, Germany
U. Von Humboldt, Berlín, Germany
IFAE Barcelona, SpainUAB Barcelona, Spain
UCM Madrid, Spain
U. Padova/INFN Padova, ItalyU. Siena/INFN Pisa, Italy
U.Udine/INFN Trieste, Italy
ETH, Zurich, Switzerland
Crimean Observatory, UkraineU.C. Davis, U.S.A.
U. Lodz, PolandINR Moscow, Russia
U. Potshefstroom, South AfricaTuorla Observatory, Finland
Yerevan Phys. Institute, ArmeniaLa Palma, Canary Islands, Spain
THE MAGIC COLLABORATION
TNG
MAGIC
NOTING
Canary Islands
La Palma
The Site: Roque de Los Muchachos
The Site:The Site: Roque Roque de Los de Los MuchachosMuchachos
Control HouseControl House
MAGIC TelescopeMAGIC Telescope
HEGRAHEGRA--CTsCTs
EnergyThreshold
Ω - Pixel Solid Angleτ - Integration time
A - Mirror Areaε - Quantum Efficiency
Lowering the Energy Threshold
ετφ
AEth
Ω∝
Energy Threshold Mirror Area17 m diameter240 m2 diamond milled Al85%-90% reflectivityBuilt by MERO
ετφ
AEth
Ω∝
Lowering the Energy Threshold
Energy Threshold Pixel Solid Angle
EMI 9116A, 9117ARb-bialkali photocathode
Borosilicate hemispherical window
577 PMTs
Lowering the Energy Threshold
1”
2”
ετφ
AEth
Ω∝
Energy Threshold Quantum Efficiency
Lacquer
PTP+B-72+Dichloromethane
1. Increase γ path length
2. Light collector to cross twice the photocathode
∆QE ~ +30% XX
Lowering the Energy Threshold
ετφ
AEth
Ω∝
Lowering the Energy Threshold
Integration timeEnergy Threshold
Flash ADC @ 330 MHz, 8 bit
High Gain
High/Low gain (x5)
Dynamic range: 2000 (high/low gain)DAQ: Continuous ~20 Mbytes/sec ~1% deadtime @ 1 kHzInternal FIFO for 150 000 events (>20 kHz) Gamma Ray Bursts
Lowering the Energy Threshold
ετφ
AEth
Ω∝
DiscriminatorsDiscriminators
Level 1Level 1
# of photoelectrons
tight time coincidence
Level 2Level 2advanced pattern
recognition
The Trigger Architecture
A) Optimize focus on lamp (920 m)B) Memorize panel & laser positions
PSF
Laserpointers
Tracking of Jupiter
With AMC (positions from tables)
Without AMC
focusseddefocussed
Increasing zenith angle
Active Mirror Control
Muon rings
Real muon event
Muon rings can be used for calibration and flat-fieldingImages are determined by geometry onlyGood correlation between arc length and SIZEMeasure the charge in ring calculate conversion factorsUsed for calibration (25% agreement with LED pulser)
Image description by Hillas parametersWidth, LengthConcentrationSizeAlpha
Signal discrimination based on cuts of these parameters
γ showers point to source Alpha <10°
Analysis Technique
See M.Lopez et al. (poster 3.56)
Preliminary results: Crab
Excess = 287 events
Background = 303 events
Crab nebula (galactic SNR)Steady Gamma emission (standard candle): useful for calibration Very first look: ~50 minutes observation time detection !~ 8.0 events/minute after simple cuts
Significance ~ 10 σSignificance ~ 10 σ
Preliminary results: Mrk 421
Excess = 1307 events
Background = 565 events
Significance ~ 27 σSignificance ~ 27 σ
Mrk 421 (BL Lac, z=0.031) was flaring in FebruaryObservation time ~100 minutes27 sigma significance after simple cuts
MAGIC Milestones2000-2003 Construction of the telescope
Dec 2001 Dec 2001 -- FrameFrame 2002 2002 -- FrameFrame
2002 2002 -- CameraCamera
20032003
Nov 2002 Nov 2002 -- Trigger/DAQTrigger/DAQ
MAGIC Milestones
29 May 2003 First cosmics observed
2000-2003 Construction of the telescope
MAGIC Milestones
10 Oct 2003 Inauguration29 May 2003 First cosmics observed
2000-2003 Construction of the telescope
15 Feb 2004 First γ-ray source detections
MAGIC Milestones
10 Oct 2003 Inauguration29 May 2003 First cosmics observed
2000-2003 Construction of the telescope
MAGICMAGIC--II II (17 m)(17 m)MAGICMAGIC--I I (17 m)(17 m)
DesignDesign StudyStudy forfor ECOECO--1000 (35 m)1000 (35 m)a 34m a 34m telescoptelescopeeastroastro--phph/0403180/0403180
Build a second telescope⇒ Same mechanical structure⇒ Test bench for technical developments
Future Prospects and Developments
Conclusions
MAGIC MAGIC isis out out there forthere for real!real!
MAGIC MAGIC willwill explore explore the subthe sub--100 100 GeV window thanks to the many innovations GeV window thanks to the many innovations that have been introducedthat have been introduced
Many people have contributedMany people have contributed ((many studentsmany students…) …)
MAGIC has MAGIC has detected the first sourcesdetected the first sources ((CrabCrab,Mrk421) ,Mrk421) just just -- 6 6 months after the inauguration months after the inauguration -- onlyonly 3 1/2 3 1/2 years after initial funds were raisedyears after initial funds were raised
Lots of work still toLots of work still to be done! (be done! (calibrationscalibrations, “, “Low ELow Ethth”, …)”, …)
EnterEnter normal normal operation modeoperation mode in in OctoberOctober 20042004
MAGIC MAGIC isis a a discovery telescopediscovery telescopeAim at the detection of many new sourcesAim at the detection of many new sources !!
FIN