A Multi - wavelength Study of Blazars with WIYN- VERITAS-IceCube Kirsten L. Larson The College of Wooster Advisor: Teresa Montaruli University of Madison-Wisconsin Picture from:

Blazars Our Blazars: Markarian 421 (z = 0.031) Markarian 501 (z = 0.034) 1ES (z = 0.047) Blazars are AGN with the jets pointed toward us. Picture from:

γ-ray -- Neutrino Connection

Multi-wavelength Campaign WIYN 0.9m Whipple 10m IceCube

Markarian 421 Mrk 421 was first detected in 1992 and was first extragalactic VHE gamma-ray source. The first flare was observed in 1994 when the flux increased from 0.15 Crabs to 1.5 Crabs. Since then, large flares have been observed in 1996, 2000, 2003 and Schubnell et al. (1996)

Mrk 421 Throughout 1997 and 1998 Mrk 421 had an average flux of 0.5 Crabs and flared only 3 times to about 1 Crab. In May Mrk 421 flared to about 10 Crab, doubling its intensity in less then an hour. By May 8 its flux was back down to 0.3 Crabs. A Flare on May 15 showed variability on a 15 min. time scale Gaidos et al. (1996)

Mrk 421 On April 2004 Mrk 421 had a flare that lasted more then 2 weeks with a flux reaching as high as 3 Crabs. In 2000/2001 Mrk 421 had high flaring ranging from 0.4 to 13 Crabs and lasted for about 5 months. The Flux was steady throughout 2002/2003 until March 30, 2003 when it flared again. Blasejowski et al (2005) David Steele

Our Observing Period: 18 April – 10 May 15 June – 19 June Optical and Gamma-Ray Data

WIYN 0.9m

Raw Image Reduced Image Mrk Source (Mrk 421) and three stable reference stars to calibrate magnitude Used IRAF to quantify “instrumental” magnitudes Image needs to be reduced to account for instrumental effects (like the white line)

Mrk 421 Above: WIYN optical data for 18 Apr – 10 May & June Below: Whipple data for the same period Above: Whipple gamma-ray data Nov 05 – Jun 06. Our period is in the red box. One jansky = 1E-23 erg/s/cm^2/Hz Preliminary data

Mrk 501 Above: WIYN optical data for 18 Apr – 10 May & 15 June – 19 June 2006 Below: Whipple data for the same period Above: Whipple gamma-ray data Mar 06 – Jun 06. Our period again is in the red box. Preliminary data

1ES Above: WIYN optical data for 18 Apr – 10 May & 15 June – 19 June 2006 Below: Whipple data for the same period Above: Whipple gamma-ray data Nov 05 – Jun 06. Our period is, still, in the red box. Preliminary data

Maximum Likelihood Blocks ● Separates photon count data into regions of likely constant flux ● References: J. D. Scargle, “Bayesian Blocks, a New Method to Analyze Structure in Photon Counting Data”, 1998 E. Flaccomio, “Maximum Likelihood Blocks for the Analysis of Time Series” (presentation)

Long Term Whipple Data For Mrk Flux above 1.5 Crabs 23.5% of the time Likelihood Factor: 20 Daily Averages Used the Maximum likelihood method and the Flux in Gamma/Run.

Spectral Energy Distribution One zone SSC( Synchrotron Self-Compton) model Synchrotron Inverse Compton with Extragalactic extinction B V Mrk 421 SED from Blazejowski et al.

Future Plans Analyze AMANDA data in this period, looking for neutrinos coincident with flaring. Analyze AMANDA data in this period, looking for neutrinos coincident with flaring. Whipple and VERITAS will continue to take gamma ray data on the blazars, and a new series of WIYN observations is planned for fall. Whipple and VERITAS will continue to take gamma ray data on the blazars, and a new series of WIYN observations is planned for fall. Mrk Nov 4 – Jan 31 1ES Sept 1 – Jan 31 1ES Sept 1 – Jan 31 1ES Sept 1 – Jan 31 1ES Nov 4 – Jan 31

Analysis Team  Teresa Montaruli – University of Madison-Wisconsin  Matthew Bayer – University of Madison-Wisconsin  David Steele – Adler Planetarium / VERITAS Collaboration

References Markarian 421 Schubnell et al., “Very High Energy Gamma-Ray Emission from the Blazar Markarian 421” Gaidos et al. “Extremely rapid bursts of TeV photons from the active galaxy Markarian 421” Frank Krennrich, “TeV Gamma-ray Astronomy in the new Millennium” Blazejowski et al., “A Multiwavelength View of the TeV Blazar Markarian 421: Correlated Variability, Flaring, and Spectral Evolution” Markarian 501 J. Quinn et al., “Detection of Gamma Rays with E > 300 GeV from Markarian 501” M. Gliozzi et al.,“Long-Term X-ray and TeV Variability of Mrk 501” ES Jamie Holder, “Detection of TeV Gamma Rays from the BL Lacertae Object 1ES with the Whipple 10 Meter Telescope” H. Krawczynski et al. “ Multiwavelength Observations of Strong Flares from TeV Blazar 1ES ” 2004.