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Part 1 - Notes from the meeting
Sparse notes from TOPIC 1 - BLAZAR
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VARIABILITY
Malaga 2016 MW conference jets2016.iaa.es
One of the best example are Jorstad et al. with BL Lac, GASP large database of radio-optical flux data on BL Lac (other example NRAO 530/PKS 1730-13), emission lines blazar PKS 1510-08, 3C 454.3, 3C 279 (optical magnitude more bright after the ejection of a huge bright superliminal superluminal radio componentcomponents)
Svetlana J.: 1. theoreticians have to pay attention to these behaviors. 2. what theoreticians want form from MW campaigns/observations? 3. there are needs to justifications in maintain VLBI monitor for example.
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Stefano C.: eRosita MoU with Fermi ? (unid. sources, blazar association, population studies, etc.). What we have learned from the observation (for the first time) of low gamma-ray states (for example in 3C 454.3, in PKS 1510-08, ...)?. GAIA mission (some strips of the sky scannes scanned also 70 times i.e. multi-epoch data) and possible studies of the photocenter shift localization of the optical emission zone during gamma-ray flares (origin of gamma-ray emission and the blazar zone emission production). Only for bright optical balzars (mag < 17 ?) anyway.
Sparse notes from TOPIC 2 - AGN DEMOGRAPHY
Matt L.talk: 1 SED (nu peak, synch/IC peaks, Compton dominance, SED dependence on optical class? jet kinetic power? other props?); 2 Luminosity functions (beamed vs umbeamedunbeamed, dependence on optical class) ; 3 Nature of unidentified sources (how many are the blazars? can we predict their SEDs at low energies based on Fermi SEDs?); 4. fundamental properties of blazars ? which are the most useful classifications ? (SED peaks, luminosity, frequency, jet Lorentz factor/Doppler factor, BLR/no-BLR ?).
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Benoit L.: BL Lac objects show some correlations i tyerms in terms of blazar sequence-like (biased) schemes but not the FSRQ NOFSRQs. FSRQ are almost all low-energy peaked so the lack of correlation even if there is very broad luminosity range the range of peak frequencies is narrow.
Small number of misalined AGN (radiogalaxies) detcted detected by the LAT. THis This is a problem for population studies.
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Benoit L: More ways to associate unassociated sources ? Please propose potential new further schemes.
Determine the distribution and range of nu-synch-peak for all blazars down to some limiting flux nu-peak*f-peak? How increase the numeber number of known ISP BL Lacs? Broadband blazar surveys ? Create a way to release and publish and distribute the MW data where one is working ?
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Stefano C:-- a) Possible idea for a Memorandum of Understanding with e-ROSITA ? This will be soon finally a sensitive all-sky high-energy instrument simultaneous to Fermi LAT for joint high-energy X-ray-gamma-ray survey astronomy and time domain astronomy. -- b) Fermi with additional more 10 years of prolonged mission can be of interest from particle physics side: increase statiatic statistics and limits/detection of DM and new-physics signals + multimessenger astroparticle physics with cross correlations among the next neutrino, gravitational wave and ultra-high energy cosmic ray data coming in the next decade. Without Fermi the multi-messenger science cannot develop and grow well. Remarks for the physics community side. -- c) Without Fermi the sciencew science possible with CTA cannot develop and grow well. Remarks for the physics community side.
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Main goals of time-series (variability) analysis:
(1) identifying nature and gain physical understanding of the phenomenon/object producing the observed time series;
(2) forecasting (predicting future behavior and future values of the time series quantity).
What we can learn from short timescales (<1 day) of variability that can be pserberved observed by the LAT for very bright flares.
Search for breaks in the PDS (relation with physics, SMBH mass like for X-rays in Seyferts?).
Can the LAT allows systematic nulti-wavelength multiwavelength variability studies measuring the PDS-SED-plane (i.e. timescale-energy plane)?.
Broad-band MW studies: cross-correlation and time lags. MW SED modeling. Gamma-ray-synchrotron amplitude ratio studies, orphan flares, Physics physics of the gamma-ray emission in AGN, identification of newly discovered gamma-ray sources, spectral index hysteresis, etc.
PHYSICS OF GAMMA-RAY EMITTING AGN (includes mainly blazars and radio galaxies)
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-- C.3 WHERE are the X-rays/gamma-rays produced ?
AGN studies with GLAST: Science GoalsFermi LAT: some pre-launch science goals:
(1): Does the "blazar sequence" scheme hold for a large sample of objects?
(2): Are SSC models in trouble for the HBL-type blazars?
(3): Are single-zone synchrotron + Compton models applicable?
(4): Are synchrotron and Compton components produced co-spatially?
(5): What is the content of the innermost part of the relativistic jet?
(6): Total charged particle content / kinetic energy of the blazar jets as compared to the radiative output
(7): are gamma-ray flares related to dissipation of magnetic energy?
(8): Do blazars and radio galaxies accelerate ultra-high energy cosmic rays?
(9): Tests of the Compton-scattered CMBR interpretation of extended X-ray (Chandra) jets
(10): Energization Sites and Bulk Relativistic Speeds of Blazar Jets
(11): Constaints/hints on matter composition of gamma-ray emitting jet region
Variability analysis of LAT and MW data is required in most of these topics.
Problem of faint sources: real variable source or background fluctuations?
High degree (up to 30%) and variability of the optical polarization (OP) is one of the defining properties of blazars (especially the classical BL Lac objects and high-pol. quasars HPQ). This means that OP observations are might be an important element in confirmation of new blazar candidates.
Results from the LAT paper on blazars (106 spurces) gamma-ray variability studies (first 11 month data):
LAT gamma-ray blazars are displaying 2 “flavors” of variability:
1) constant baseline with sporadic flaring activity showing also intermittence (flatter PDS, red noise); 2) a few sources showing strong activity with complex and structured time profiles characterized by the long-memory, steeper PDS slopes (random walk processes).
Dave T.:
Fermi Gamma-ray Space Telescope characteristics and experience from 7 years in orbit.
Methods for simultaneous studies: 1.Wide-field telescopes 2.Monitoring programs 3.Dedicated multiwavelength campaigns 4.Good luck
Methods for near-simultaneous/follow-up studies: Rapid sharing of information
The Fermi wide-field instruments are an approximation to “all the sky, all the time,” which would be needed across the electromagnetic spectrum to catch everything of interest. Probably not practical. LOFAR, MAXI, HAWC, Swift-BAT are examples of other wide-field instruments, along with multimessenger facilities like IceCube, Antares, and Advanced LIGO/Virgo. This is a developing field.
Monitoring programs are being carried out for classes of objects known to show variability or transient behavior.For Fermi, blazars and pulsars are classes of interest that are monitored (at least for a subset) at many wavelengths. Example monitoring programs include MOJAVE, OVRO (radio), Tuorla, SMARTS (optical), Swift (X-rays).
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