Frank Krennrich, for the VERITAS Collaboration (Iowa State University) Results from VERITAS...

Frank Krennrich*, for the VERITAS Collaboration Frank Krennrich*, for the VERITAS Collaboration

(*Iowa State University) (*Iowa State University)

Results from VERITASResults from VERITAS

New Opportunities at the interface New Opportunities at the interface between particle physics and between particle physics and astronomyastronomy

Tel 1Tel 2

Tel 3Tel 4

VERITAS

OutlineOutlineOutlineOutline

• VERITAS Instrument Performance

• Northern Sky seen in the first year

• Extragalactic science

• Summary

Very Energetic Radiation Imaging Telescope Array SystemVery Energetic Radiation Imaging Telescope Array System

E ~ 100 GeV - 50 TeVE ~ 100 GeV - 50 TeV

AAarea area ~ 10~ 1055 m m22

ang. Res. ~ 3’ - 6’ang. Res. ~ 3’ - 6’

Energy Res. ~ 15%Energy Res. ~ 15%

FOV ~ 3.5FOV ~ 3.500

E ~ 100 GeV - 50 TeVE ~ 100 GeV - 50 TeV

AAarea area ~ 10~ 1055 m m22

ang. Res. ~ 3’ - 6’ang. Res. ~ 3’ - 6’

Energy Res. ~ 15%Energy Res. ~ 15%

FOV ~ 3.5FOV ~ 3.500

VERITAS CollaborationVERITAS CollaborationVERITAS CollaborationVERITAS CollaborationU.S.Adler Planetarium Argonne Nat. Lab. Barnard College DePauw U. Grinnell College Iowa State U. Purdue U. Smithsonian UCLAUCSCU. Of ChicagoU. of DelawareUniv. of IowaU. of MassachusettsU. of UtahWashington U.

CanadaMcGill U.

U.K.Leeds U.

IrelandCork Inst.Tech.Galway-Mayo Inst.N. U. I., GalwayU. College Dublin

+ 25 Associates

Supported by: SI, NSF & DOE (US), PPARC (UK), Supported by: SI, NSF & DOE (US), PPARC (UK), NSERC (Canada), SFI (Ireland) NSERC (Canada), SFI (Ireland)Supported by: SI, NSF & DOE (US), PPARC (UK), Supported by: SI, NSF & DOE (US), PPARC (UK), NSERC (Canada), SFI (Ireland) NSERC (Canada), SFI (Ireland)

VERITAS-4 Construction funded in 2003VERITAS-4 Construction funded in 2003VERITAS-4 Construction funded in 2003VERITAS-4 Construction funded in 2003

VERITAS ObservatoryVERITAS ObservatoryVERITAS ObservatoryVERITAS Observatory

T1Jan 2005T1Jan 2005

T2Spring 2006T2Spring 2006

T3Fall 2006T3Fall 2006

T4Spring 2007T4Spring 2007

TeV Monitoring capability TeV Monitoring capability TeV Monitoring capability TeV Monitoring capability

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are needed to see this picture.







VERITAS TelescopeVERITAS TelescopeVERITAS TelescopeVERITAS Telescope

Cont

rol

Room

Davies-Cotton f/1.0 Optics. Total area=110m2

Cont

rol

Room

Davies-Cotton f/1.0 Optics. Total area=110m2

VERITAS TelescopeVERITAS TelescopeVERITAS TelescopeVERITAS Telescope

Stereoscopic EventsStereoscopic EventsStereoscopic EventsStereoscopic Events

Angular ResolutionAngular ResolutionAngular ResolutionAngular Resolution

o

Courtesy Asif Imran



VERITAS SensitivityVERITAS SensitivityVERITAS SensitivityVERITAS Sensitivity

1% Crab in 47 hours

5% Crab in 2.5 hours

5σ Detection Sensitivity

• Measured sensitivity to the Crab

Nebula at high elevation (>65°)

• HESS ~ 1% Crab in 25 hours

• MAGIC ~ 2% Crab in 50 hours

TeV TeV -ray Sky -ray Sky TeV TeV -ray Sky -ray Sky W Comae

IC 443

Crab Nebula

Mrk 421

Mrk 501

Cas A

1ES 2344+514

LSI +61 303

1ES 0806+524

1ES 1218+304

M87

Key Science QuestionsKey Science QuestionsKey Science QuestionsKey Science Questions• Origin of Cosmic rays - galactic/Extragalactic

• Relativistic Jets & Black holes - leptonic vs. hadronic jets

• Dark Matter - Neutralino Annihil. Signature - LHC - direct detection - Storage

• TeV beam in extragalactic space

- test dispersion relation of light - Q.G.

- how far do we see? Opacity?

- Probe Cosmic Infrared Background

Science ProgramScience ProgramScience ProgramScience Program

Observations:~ 800 hrs / year+ ~ 200 hrs / year moonlight

Discretionary (10%)

Bulk Program (40%)

ToO’sGRB’s (priority)etc.

Sky Survey(Cygnus region) BLAZARS SNRs/PWN Dark Matter

Key Science Projects (50%)

Science Groups:

Astroparticle Physics Blazars Dark Matter Extragal. Sources Galactic Compact Galactic Diffuse GRB’s PWN & SNR’s Unidentifieds

recent discoveries recent discoveries

Multiwavelength ScienceMultiwavelength Science

EBL EBL

recent discoveries recent discoveries

Multiwavelength ScienceMultiwavelength Science

EBL EBL

Extragalactic Science Extragalactic Science Extragalactic Science Extragalactic Science

1ES 0806+5241ES 0806+5241ES 0806+5241ES 0806+524



ATEL#1415

Prelim

inary

P. Cogan, in preparation

- “ “best candidate” TeV best candidate” TeV

BL Lacs (Costamante & BL Lacs (Costamante &

Ghisellini 2002) Ghisellini 2002)

- HBL- HBL

- z = 0.138- z = 0.138

- 5.8 - 5.8 in ~ 40 hours in ~ 40 hours

- flux ~ 0.01 Crab- flux ~ 0.01 Crab

- weakest VERITAS blazar - weakest VERITAS blazar

W ComaeW ComaeW ComaeW Comae

Courtesy of M. Beilicke

- radio 1971, X-ray 1980radio 1971, X-ray 1980

- IBL (between LBL- HBL)- IBL (between LBL- HBL)

- seen by EGRET: - seen by EGRET:

0.1 -10 (27) GeV 0.1 -10 (27) GeV

- z = 0.102- z = 0.102

- 4.9 - 4.9 in ~ 40 hours in ~ 40 hours

- outburst March 08- outburst March 08

(> 8 (> 8 detection) detection)

- Quasi-- Quasi-simulataneous simulataneous

X-ray data (Swift) X-ray data (Swift)

ATEL#1422









t 1.290.28 days





dNdE

E 3.810.35stat


Quasi-simultaneous data March 14/15 2008Quasi-simultaneous data March 14/15 2008from AAVSO, UVOT, XRT, VERITASfrom AAVSO, UVOT, XRT, VERITAS



- one-zone SSC/one-zone SSC/

weak B-field weak B-field

- EC model/ - EC model/

B ~ 0.3 G B ~ 0.3 G

- GeV/TeV obs.- GeV/TeV obs.

critical critical

M87M87M87M87HSTM87 - Giant elliptical GalaxyGiant elliptical Galaxy

- D ~ 16 Mpc- D ~ 16 Mpc

- Misaligned jet (<20- Misaligned jet (<20oo) )

- First non-blazar VHE - First non-blazar VHE

source outside galaxy source outside galaxy

- Candidate UHE cosmic - Candidate UHE cosmic

ray accelerator ray accelerator

- Synch. X-ray source - Synch. X-ray source

-> E >10 TeV electrons -> E >10 TeV electrons

- close up view of a jet!- close up view of a jet!

4 4 evidence (HEGRA 03) evidence (HEGRA 03)

M87M87

- UHE cosmic rays? UHE cosmic rays?

- Synchr. Proton Blazar?- Synchr. Proton Blazar?

- Synchr. Self Compton- Synchr. Self Compton

- inv. Compton in kpc jet- inv. Compton in kpc jet (no time variations) (no time variations)

- annihilation of SS dark matter- annihilation of SS dark matter

- Where do TeV photons originate?- Where do TeV photons originate?

p π0

+





M87M87M87M87

- M87 under the M87 under the “microscope” in “microscope” in radio-optical-X-ray radio-optical-X-ray- variable in X-rays- variable in X-rays- TeV “image” is not - TeV “image” is not resolved resolved

15 “15 “

80 pc80 pc

M87M87M87M87

15 “15 “

80 pc80 pc

M87M87M87M87- M87 under the M87 under the “microscope” in “microscope” in radio-optical-X-ray radio-optical-X-ray- variable in X-rays- variable in X-rays- TeV “image” is not - TeV “image” is not resolved resolved

VHE/X-ray VHE/X-ray LongLong-Term-TermCorrelationCorrelation

Acciari et al. (VERITAS collaboration),ApJ, 679, 1427 (2008)

M87M87M87M87

VHE/X-ray VHE/X-ray ShortShort-Term-TermCorrelationCorrelation

Hui et al 2008 (VERITAS collaboration), in preparation

M87M87M87M87

VHE/X-ray Long-term Light CurveVHE/X-ray Long-term Light Curve

Hui et al 2008 (VERITAS collaboration)



Joint campaignJoint campaignHESS/MAGIC/VERITAS HESS/MAGIC/VERITAS > 120 h in 2008> 120 h in 2008Stay tuned!Stay tuned!

1ES 2344+5141ES 2344+5141ES 2344+5141ES 2344+514

- HBL- HBL- z = 0.044- z = 0.044- discovered- discovered 1995 by 1995 by Whipple Whipple- 0.07 Crab- 0.07 Crab

- VERITAS Observations Oct. 07 - Jan. 08VERITAS Observations Oct. 07 - Jan. 08- 20.5 - 20.5 detection detection- Swift: highest known X-ray flux on Dec. 8 07- Swift: highest known X-ray flux on Dec. 8 07- VHE flux on Dec. 6/7 07: 0.41 Crab- VHE flux on Dec. 6/7 07: 0.41 Crab



Mrk 421Mrk 421Mrk 421Mrk 421



ATEL#1506

- HBL- HBL- z = 0.031- z = 0.031- “old faithful”- “old faithful”- Early 2008:- Early 2008: 0.3 - 10 Crab 0.3 - 10 Crab- TeV monitor of - TeV monitor of transients transients









1ES 1218+30.41ES 1218+30.41ES 1218+30.41ES 1218+30.4



Courtesy of M. Beilicke Courtesy of P. Fortin

dNdE

E 3.090.34 stat

z=0.182

Probing CosmologyProbing CosmologyProbing CosmologyProbing Cosmology



Blazar: Blazar:

DN/DE ~ EDN/DE ~ E-2-2

Absorption: Absorption: exp (-exp (-(E(E))))

E ~ 1 TeVE ~ 1 TeV

~ 1 eV~ 1 eV

Nikishov, JETP, 14, 2 (1962)Nikishov, JETP, 14, 2 (1962)Gould & Schreder, Phys. Rev. Gould & Schreder, Phys. Rev. 155, 1408 (1967)155, 1408 (1967)Stecker, de Jager & Salamon, ApJ, Stecker, de Jager & Salamon, ApJ, 390, L42 (1992)390, L42 (1992)

Measured Spectrum: Measured Spectrum: dN/dE ~ EdN/dE ~ E-2-2 exp(- exp(-(E(E))))

ee--

ee++

TeV DataTeV DataTeV DataTeV Data

VERITAS

HESS

- blazars with sufficient redshift- good spectral data- sensitive to near and/or mid-IR



1ES1218+30.4 (HBL)Z = 0.182E ~ 0.2 - 1.5 TeV

1ES1101-232 (HBL)Z = 0.186E ~ 0.2 - 2.9 TeV

1ES0229+200 (HBL)Z = 0.1396E ~ 0.5 - 11.2 TeV



Aharonian et al. 2006, 2007.

3o

Constraints to Intrinsic SpectraConstraints to Intrinsic SpectraConstraints to Intrinsic SpectraConstraints to Intrinsic Spectra



New Lower limit from galaxy countsTaking into accountFuzzy fringes of galaxiesLevenson & Wright 2008

For a given measured Blazar spectrum a Higher EBL implies a Harder intrinsic spectra!

Slope of EBL spectrum is Critical for constrainingIntrinsic spectrum!

Levenson & Wright, arXiv:0802.1239v2





















EBL Lower Limits & EBL Lower Limits & Blazar Spectra Blazar Spectra

EBL Lower Limits & EBL Lower Limits & Blazar Spectra Blazar Spectra







TeV blazars seem to exhibit extremely hard spectra dN/dE ~ E-1.28+-0.20

or harder!

FK, Dwek & Imran, submitted to ApJ

SummarySummarySummarySummary

• VERITAS Performs well!

0.01 Crab (47 hr); ang. Res. ~ 0.1deg.

• Seen ~ dozen sources in the Northern Sky

• Broad Science program

• Detailed studies of M87

• Discovery of W Comae; study of IBLs

• Hard spectra of distant blazars

• EBL studies

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Frank Krennrich*, for the VERITAS Collaboration (*Iowa State University) Results from VERITAS...

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Frank Krennrich, for the VERITAS Collaboration (Iowa State University) Results from VERITAS...