The High Altitude Water Cherenkov(HAWC) TeV Gamma-Ray Observatory	

Eduardo de la Fuente Acosta
for the HAWC Collaboration
Universidad de Guadalajara, CUCEI, México
edfuente@gmail.com

Supernova and Gamma Ray Burst, 2013, Yukawa Institute for Theorethical Physics,
University of Kyoto, Octubre-November, 2013

Outline	

1	I.-	 	INTRODUCTION		

II.- 	GAMMA RAYS REMARKS		

III.- 	MILAGRO OBSEVATORY: THE FIRST GENERATION OF WATER	

CHERENKOV DETECTORS (WCD)		

IV.- 	HIGH ALTITUDE WATER CERENKOV (HAWC); THE SECOND	

GENERATION OF WCD		V.- 	

HAWC (DESIGN, COLABORATION, ELECTRONICS, DATES,	PERFORMANCE, SCIENTIFIC CASE)	

VI.- 	FIRST LIGHT AND PRELIMINARY RESULTS 		

VII.-	FUTURE		

Introduction
Gamma Ray Remarks
Milagro Observatory	 HAWC		

Results		 Future	I.- INTRODUCTION	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC

2	Results		 Future	I.- INTRODUCTION	

3

Wide Field of View, ContinuousOperations	TeV Sensitivity	

FERMI, AGILE, EGRET
HAWC
ARGO
MilagroTibet ASγ

Introduction

Gamma Ray Remarks

Milagro Observatory

VERITASHE
VERITASSSHESSMAGICMAGIC	 HAWC	

Results		 Future	I.- INTRODUCTION	Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC

4	Results		 Future	II.- Gamma Ray Emission Mechanism	

5TeV γ-rays:
production processes!

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	II.- Gamma Ray Emission Mechanism	Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results	

6	 Future	7II.- Gamma Ray Probe Accelarated Particles	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	II.- Gamma Ray Observations on Earth ?	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results	

8	 Future	II.- Gamma Ray Observations on Earth ?	

9YES	

Atmospheric	Cascades	

Cherenkov Effect	

http://www.clab.edc.uoc.gr/materials/pc/dive/cosmic_rays.html	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	II.- Gamma Ray Observations on Earth ?	

Atmospheric cascade	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results	

10	 Future	II.- Gamma Ray Observations on Earth ?	 11
Atmospheric cascade components (Gamma rays, Cosmic rays, Neutrons):	

Hadronic Component dominates in emission over the Electromagnetic Component,
therefore for gamma rays observations, a good Gamma/Hadron rejection is needed 	Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	II.- Gamma Ray Observations on Earth ?	 12
Cherenkov Effect	- In a material with refractive index, n, a charged
particle emits if its velocity is greater than thelocal phase velocity of light .	

- The charged particle polarizes the atoms along
its trajectory	

Shorter wavelenghts,
more intense	- These time dependent dipole emit
electromagnetic radiation	

Frank-Tamm Theory (1937, Nobel 1950)	

- Ifv < c / n, the dipole distribution issymmetric around the particle position, andthe sum of all dipoles vanishes	- If v > c / n, the distribution is asymmetric andthe total time dependent dipole is not null,thus radiates.		

Introduction
Gamma Ray Remarks
Milagro Observatory	 HAWC	

Results		 Future	II.- Gamma Ray Observations on Earth ?	 13
Air Cherenkov Detectors	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	II.- Gamma Ray Observations on Earth ?	 14
Water Cherenkov Detectors	

Shower Front	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	Results		 Future	III.- First Generation on WCD	Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results	15	 Future	III.- First Generation on WCD	16See MILAGRO (LANL; 60 x
80 x 8 m; Abdo et al., 2007,2009, for details.
Threshold: 500 GeV. 6.5
years of data (Jul 2000 –Jan 2007); crab nebula 15
sigmas, GP clearly visible	

Abdo et al., ApJ Lett 2009	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	IV.- High Altitude Water Cherenkov (HAWC)
Observatory: Second Generation (WCD)	

1715 times Milagro Sensitivity	Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	IV.- High Altitude Water Cherenkov (HAWC)
Observatory: Second Generation (WCD)	

18

High Altitude lowers energy threshold	

4100m
2800m
The scale lenght for the energy loss of e and photons when interacts
with matter (gr cm-2)• Higher Altitude means fewer radiation lengths andmore particles• Fluctuations in first interaction means more particles• For example 5% of events (e-3=5%) will have 5 x moreparticles
Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	IV.- High Altitude Water Cherenkov (HAWC)
Observatory: Second Generation (WCD)	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	Results	

19	 Future	IV.- High Altitude Water Cherenkov (HAWC)
Observatory: Second Generation (WCD)	

20

HAWC Large field of view, continously operating high energy gamma ray
observatory (100 GeV to hundreds TeV). One of the primary goals of HAWC isto identify new TeV gamma-ray sources and extended measurements of known
sources to higher energies. Spectra studies up to 10 TeV (e.g., SEDs), Monitoring(Transients, GRB, AGN), Large Scale (Anisotropy), Diffuse emission.	

-	AIMS		

Provide an unbiased map of the TeV sky (2.5π sr/day)	

Study transient emission from sources like AGNs	

Search for 100 GeV emission from GRBs	

Measure the energy spectrum of Galactic sources up to the highest energies	Measure diffuse emission between 1 and 100 TeV	Study small and large scale anisotropy of cosmic rays at energies > 1 TeV	

Search for new physics at TeV energies	

Provide TeV alerts for other instruments	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	V.- High Altitude Water Cherenkov (HAWC)
Observatory: Second Generation (WCD)	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results	

21	 Future	V.- High Altitude Water Cherenkov (HAWC); Design	

22

300 hundred tanks(detectors) atcompletion, covering
20,000 m2, 4100 m asl.

Each tank with 200,000
liters of ultra-pure waterand 4 PMTs

Modular Construction, actual 111 detectors areoperational
Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	V.- High Altitude Water Cherenkov (HAWC); Design	Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results	

23	 Future	24

V.- High Altitude Water Cherenkov (HAWC); Electronics	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	25

V.- High Altitude Water Cherenkov (HAWC); Electronics	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	26

V.- High Altitude Water Cherenkov (HAWC); Performance	See: Abeysekara et al., “Sensitivity of the High Altitude Water Cherenkov Detector to Sources of MultiTeV Gamma Rays”, Astroparticle Physics, accepted (arxiv: 1306.5800)	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	

27

V.- High Altitude Water Cherenkov (HAWC); Performance	Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	28

V.- High Altitude Water Cherenkov (HAWC); Performance	

Better Gamma /H a d ro n R e j e c t i o nt h a n M i l a g ro a n d
A R G O - Y B J . Ve r yimportant issue.	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	VI.- First Light and Preliminary Results	

29

HAWC 30 (detectors) Full Moon	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	VI.- First Light and Prelimary Results	

30

The observation of the Moon shadow can provide a direct check ofthe relation between size and primary energy: è Energy
Calibration

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	VI.- First Light and Prelimary Results	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results	

31	 Future	VI.- Prelimary Results	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC

32	Results		 Future	VI.- Prelimary Results	

33

Unexpected Anisotropy of 10 TeV Cosmic Rays; Gyroradius of 10TeV proton in 2µG field is 1000 AU	

Astroparticle Physics, in preparation 	

Point of Contact: Segev Benzvi and Dan Fiorino; Univesity of Wisconsin	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	VI.- Prelimary Results	

34

ARGO-YBG vs. HAWC 95	

Astroparticle Physics, in preparation 	

Point of Contact: Segev Benzvi and Dan Fiorino; Univesity of Wisconsin	

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	VI.- Prelimary Results	

Point of Contact and Credit: Dmitry Lennarz (PSU). See also Julie McEnery (NASA Goodard) talk on GRB conference 	

Paper in preparation, see also Abeysekara et al., Astropart.Phys. 35 (2012) 641-650. Also arXiv: 1108.6034	

1108.6034 [astro-ph.HE]	

Introduction
Gamma Ray Remarks
Milagro Observatory	 HAWC	

Results		

35	 Future	VII.- Preliminary Results (Diffuse Emission)	

36

Paper to be published, See Huntemeyer et al., 2013, Proceedings of the ICRC 2013
Point of Contact: Petra Huntemeyer, Michele Hui, and Hugo Ayala (Michigan Tech, Houghton)

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	VII.- Future (Supernova Remnants)	

37

Mexican Group (IA-UNAM, UAEH, U de G, ICN-UNAM) created tostudy supernova remnants (plerions and Pulsar Wind Nebula; see
Ambrocio-Cruz & de la Fuente poster).
Focus in those Supernova Remants reported by MILAGRO
Perform optical (Polarimetry and Fabry-Perot), X-Ray, and Gamma-Ray
with HAWC. Contrasting between observations		Polarization can be produced by anisotropic radiation processes (Light scattering,Zeeman effect, Synchrotron emission, Dichroic absorption, birefringence); A more direct
way to investigate the magnetic field configuration.		

Multi-Wavelenghts (MW) observations are useful to detect structures and brightfeatures associated with the PWN, to confirm theoretical models associated with thenature of the emission, and determine regions of diferent emission (e.g., Radio;
Syncrotron, and Gamma Rays; accelerated protons interacting with molecular clouds) inSupernova Remnants.		

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	38VII.- Future and Sinergy of HAWC with other experiments	

Complements TeV atmospheric Cherenkov telescopes (whichhave <3 degree field of view and <10% duty factor)
Identifies new and flaring sources for follow up observation of morphology
and sub TeV spectra
Extends TeV spectra to higher energies

Complements GeV All Sky Survey
Monitors 1000s of Fermi GeV sources at higher energies

Complements TeV neutrino observations
Identifies new and flaring TeV sources to improve the sensitivity andinterpretation of blind searches

Complements Advanced LIGO		

Simultaneous observations of nearby, short GRBs from ns-ns inspiral

Introduction

Gamma Ray Remarks

Milagro Observatory	 HAWC	

Results		 Future	THANK YOU!