BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Wide-range multiwavelength observations of Northern TeV blazars wi th Suzaku\, MAGIC and HESS DTSTART;VALUE=DATE-TIME:20070706T170500Z DTEND;VALUE=DATE-TIME:20070706T171700Z DTSTAMP;VALUE=DATE-TIME:20261016T112627Z UID:indico-contribution-106-0-930@cern.ch DESCRIPTION:Speakers: Mr. HAYASHIDA\, Masaaki (Max-Planck-Institut fuer Ph ysik\, D-80805 Muenchen\, Germany)\nElectromagnetic radiation from blazars can be observed from the radio band up to very high energy \ngamma rays\, with spectral energy distributions (SEDs) apparently characterized by a t wo-bump structure. So far\, \nmost of the measured SEDs could be interpret ed using simple leptonic origin scenarios\, like Synchrotron Self-\nCompto n models. However\, models where the gamma rays are due to accelerated pro tons could also explain the \nSEDs of blazars. The complex pattern of vari ability observed in blazars shows extremely short time scales and \nlarge amplitudes at the highest energies. Hence\, in order to investigate the or igin of the emission and the \nacceleration mechanism in the jet\, simulta neous multiwavelength observations are essential.\nIn 2006\, multiwaveleng th campaigns with the Suzaku satellite\, sensitive from soft to hard X-ray s\, and ground \nbased MAGIC/HESS observatories\, measuring from energies above 100 GeV to some tens of TeV\, were conducted \nfor several northern TeV blazars. Here\, the observations made in these campaigns are presented and the \nmeasured SEDs will be discussed.\n\nhttps://indico.nucleares.un am.mx/event/4/session/106/contribution/930 LOCATION:Merida\, Mexico Uxmal + Tulum (Holiday Inn) URL:https://indico.nucleares.unam.mx/event/4/session/106/contribution/930 END:VEVENT BEGIN:VEVENT SUMMARY:A Spectacular VHE Gamma-ray Outburst from PKS 2155-305 in 2006 DTSTART;VALUE=DATE-TIME:20070706T171700Z DTEND;VALUE=DATE-TIME:20070706T172900Z DTSTAMP;VALUE=DATE-TIME:20261016T112627Z UID:indico-contribution-106-0-1221@cern.ch DESCRIPTION:Speakers: Dr. BENBOW\, Wystan (Max Planck Institut fuer Kernph ysik)\nA spectacular outburst of VHE (>100 GeV) gamma-ray emission \nwas o bserved from PKS 2155-304 in 2006 with the H.E.S.S. experiment.\nThe VHE f lux reached levels of ~20 times the Crab Nebula flux\, \nmore that 2 order s of magnitude above typical values \nobserved from the object. This extr emely high flux\, \nwhen coupled with the sensitivity of H.E.S.S.\,\nenabl es temporal studies of the emission\nwith unprecedented resolution. Severa l fast flares\, \nanalogous to bursts\, were resolved allowing\nfor very s trong constraints on the underlying physical processes.\nThe temporal char acteristics\, spectral evolution and\nbroadband characteristics of these 2 006 outbursts will be presented.\nIn addition\, the challenges these data present\nto standard paradigms of TeV Blazars\, particle acceleration\npro cesses\, and radiation mechanisms will be discussed.\n\nhttps://indico.nuc leares.unam.mx/event/4/session/106/contribution/1221 LOCATION:Merida\, Mexico Uxmal + Tulum (Holiday Inn) URL:https://indico.nucleares.unam.mx/event/4/session/106/contribution/1221 END:VEVENT BEGIN:VEVENT SUMMARY:Snapshot Observations and Time-resolved Modeling of Gamma-ray Blaz ars during Major Flares DTSTART;VALUE=DATE-TIME:20070706T172900Z DTEND;VALUE=DATE-TIME:20070706T174100Z DTSTAMP;VALUE=DATE-TIME:20261016T112627Z UID:indico-contribution-106-0-1211@cern.ch DESCRIPTION:Speakers: Dr. CARSON\, Jennifer (Stanford Linear Accelerator C enter)\nMajor blazar flares likely result from injections of relativistic pair plasma into\nthe inner jets. Quantifying the jet’s basic physical p arameters has been hampered by\nthe modest sensitivity of past observation s\, which has allowed only time-averaged\npictures of these rapidly changi ng phenomena. The capabilities of gamma-ray\nobservatories have dramatical ly improved recently with H.E.S.S. and MAGIC\, and the\nimprovements conti nue in 2007 with the advent of VERITAS and the Large Area Telescope\n(LAT\ , 30 MeV < E < 300 GeV) aboard GLAST. These instruments can measure the sp ectra\nof flaring blazars on time scales of hours or less\, shorter than t he expected cooling\ntime scales of the pair population. Using a sophistic ated code based on the work of\nM. Boettcher and extended by us\, we explo re the effects of various cooling mechanisms\nand jet physical conditions on the SED “snapshots” that are possible with joint\nLAT/TeV observati ons. The code includes cooling via synchrotron\, synchrotron\nself-Compton \, and external Compton radiation\, allows for finite jet injection times\ ,\nand evolves the pair population self-consistently as it cools after a m ajor flare. We\ndemonstrate the power of such snapshot observations in con straining the jet physics\nand the importance of adequate modeling to inte rpret the observations.\n\nhttps://indico.nucleares.unam.mx/event/4/sessio n/106/contribution/1211 LOCATION:Merida\, Mexico Uxmal + Tulum (Holiday Inn) URL:https://indico.nucleares.unam.mx/event/4/session/106/contribution/1211 END:VEVENT BEGIN:VEVENT SUMMARY:Successful ToO triggers on the extragalactic sources with the MAGI C telescope DTSTART;VALUE=DATE-TIME:20070706T174100Z DTEND;VALUE=DATE-TIME:20070706T175300Z DTSTAMP;VALUE=DATE-TIME:20261016T112627Z UID:indico-contribution-106-0-936@cern.ch DESCRIPTION:Speakers: Mr. MAZIN\, Daniel (Max-Planck-Institute for Physics \, Munich)\nThe MAGIC collaboration has been performing Target of Opportun ity (ToO) observations\nwhenever alerted that known or potential very high energy gamma-ray emitting\nextragalactic sources were in a high flux stat e in the optical\, X-ray band or/and in\nthe TeV energy range. Here we rep ort on triggered observations\, results of the\nanalysis\, and possible op tical-TeV correlation seen in the data. Among other sources\,\ndetections as well as spectral and temporal characterestics of Mkn 180 and PKS\n2155- 304 will be reported.\n\nhttps://indico.nucleares.unam.mx/event/4/session/ 106/contribution/936 LOCATION:Merida\, Mexico Uxmal + Tulum (Holiday Inn) URL:https://indico.nucleares.unam.mx/event/4/session/106/contribution/936 END:VEVENT BEGIN:VEVENT SUMMARY:Observations of Gamma-ray Bursts with VERITAS and Whipple DTSTART;VALUE=DATE-TIME:20070706T175300Z DTEND;VALUE=DATE-TIME:20070706T180500Z DTSTAMP;VALUE=DATE-TIME:20261016T112627Z UID:indico-contribution-106-0-406@cern.ch DESCRIPTION:Speakers: Dr. HORAN\, Deirdre (Argonne National Laboratory)\nM any authors have predicted very high energy (VHE\; E > 100 GeV) emission f rom\ngamma-ray bursts (GRBs) both during the prompt phase and during the m ulti-component\nafterglow. To date however\, there has been no definitive detection of such emission.\nRecently\, Swift made the exciting discovery that almost half of GRBs are accompanied\nby one or more X-ray flares whic h are found to occur from several seconds to many hours \nafter the prompt emission. The discovery of this phenomenon and the many\npredictions that VHE emission should accompany these flares increases the already\nstrong motivation for making immediate follow-up VHE observations of GRBs.\nObser vations of GRBs have high priority at VERITAS\, preempting any observation s which\nmay be in progress. GRB alerts are received from the GCN via a so cket connection and\nthis is interfaced to the VERITAS Tracking Software t o minimize the time between a\nnotification arriving and the telescope bei ng commanded to slew to the GRB. We report\nhere on GRB observations with VERITAS and with the Whipple Telescope from 2005 through\n2007. The substa ntial sensitivity of VERITAS to GRB emission over many time-scales is\nals o discussed.\n\nhttps://indico.nucleares.unam.mx/event/4/session/106/contr ibution/406 LOCATION:Merida\, Mexico Uxmal + Tulum (Holiday Inn) URL:https://indico.nucleares.unam.mx/event/4/session/106/contribution/406 END:VEVENT BEGIN:VEVENT SUMMARY:Synchrotron emission in GRB prompt phase using a semi leptonic and hadronic model DTSTART;VALUE=DATE-TIME:20070706T180500Z DTEND;VALUE=DATE-TIME:20070706T181700Z DTSTAMP;VALUE=DATE-TIME:20261016T112627Z UID:indico-contribution-106-0-1079@cern.ch DESCRIPTION:Speakers: GUIRIEC\, Sylvain (LPTA\, Université Montpellier 2\ , CNRS/IN2P3\, Montpellier\, France)\nThe "fireball model" is often invoke d to explain the prompt emission from Gamma-Ray\nBursts (GRBs) as observed in the MeV energy range. In this standard model\, the prompt\nemission\no ccurs due to collisions between layers within the relativistic jet. We wil l present\nthe expected\nsynchroton emission from electrons accelerated th rough the usual Fermi mechanism\,\nassuming that the\ndistribution of magn eto-hydrodynamic perturbations in the shocks is isotropic and\nfollows a\n Kolmogorov turbulence. In addition\, we can expect Ultra-High Energy Cosmi c Rays to be\naccelerated\nthrough Fermi mechanism at the very beginning o f the internal shock phase\, by\nscattering off\nrelativistic hydrodynamic fronts of the jet. We will present predictions for their\nsynchrotron\nem ission and other possible processes at very high energies (>GeV). Finally\ , we will\ndiscuss the\nsensitivity of the NASA's future telescope GLAST ( Gamma-Ray Large Area Space\nTelescope) for\nobserving GRBs following this model\, and we will address some crucial tests of the\nGRBs physics.\n\nht tps://indico.nucleares.unam.mx/event/4/session/106/contribution/1079 LOCATION:Merida\, Mexico Uxmal + Tulum (Holiday Inn) URL:https://indico.nucleares.unam.mx/event/4/session/106/contribution/1079 END:VEVENT BEGIN:VEVENT SUMMARY:The 'Supercritical Pile' GRB Model: Prompt and afterglow emission DTSTART;VALUE=DATE-TIME:20070706T181700Z DTEND;VALUE=DATE-TIME:20070706T182900Z DTSTAMP;VALUE=DATE-TIME:20261016T112627Z UID:indico-contribution-106-0-1134@cern.ch DESCRIPTION:Speakers: Prof. MASTICHIADIS\, Apostolos (Physics Dpt\, Univer sity of Athens)\nWe examine the prompt and afterglow emission\nwithin the context of the Supercritical Pile model for GRBs.\nFor this we have perfor med self-consistent calculations\nby solving three time-dependent kinetic equations for protons\,\nelectrons and photons in addition to the usual ma ss\nand energy conservation equations. We follow the evolution\nof the RBW as it sweeps up circumstellar matter and assume\nthat the swept-up electr ons and protons have\nenergies equal to the Lorentz factor of the flow.\nW hile the electrons radiate their energies through\nsynchrotron and inverse Compton radiation on short\ntimescales\, the protons\, at least initially \,\nstart accumulating without any dissipation. As the mass\nincreases\, h owever\, they might become supercritical\nto the `proton-photon pair-produ ction - synchrotron radiation'\nnetwork\, and\, as a consequence\, they tr ansfer explosively their\nstored energy to secondary electron-positron pa irs and radiation.\nThis results in a burst which has many features simila r\nto the ones observed in GRB prompt emission.\n We have included in o ur calculations the radiation drag\nforce exerted on the flow from the sca ttered radiation\nof the prompt emission on the circumstellar material.\nW e find that this can break the flow on\ntimescales which are much faster t han the ones related to\nthe usual adiabatic/radiative ones. As a result t he emission\nexhibits a steep drop just after the prompt phase\,\nin agree ment with the Swift afterglow observations.\n\nhttps://indico.nucleares.un am.mx/event/4/session/106/contribution/1134 LOCATION:Merida\, Mexico Uxmal + Tulum (Holiday Inn) URL:https://indico.nucleares.unam.mx/event/4/session/106/contribution/1134 END:VEVENT END:VCALENDAR