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A Modified Synchrotron Model (Pipe-Reservoir Model) for Knots in the M87 Jet

A Modified Synchrotron Model (Pipe-Reservoir Model) for Knots in the M87 Jet. http://www.atlasoftheuniverse.com/galgrps/m087hubble.jpg. Criterion. 1. It could be wrong , but it must be irradiative ; (e.g. Yang-Mills Equation) 2. It could be ugly , but it must be effective ;

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A Modified Synchrotron Model (Pipe-Reservoir Model) for Knots in the M87 Jet

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  1. A Modified Synchrotron Model (Pipe-Reservoir Model) for Knots in the M87 Jet http://www.atlasoftheuniverse.com/galgrps/m087hubble.jpg

  2. Criterion • 1. It could be wrong, but it must be irradiative; (e.g. Yang-Mills Equation) • 2. It could be ugly, but it must be effective; (e.g. Bohr Atom Model) • 3. It could be nothing, but it must be interesting (S.-N. Zhang 2005@USTC); • 4. Be Self-Confident (with intrepidress) and Honesty with yourself and others (P. W. Anderson, personal communication) are the most important for younger.

  3. Introduction M87( 3C 274, Virgo A, NGC 4486） Recent Observation Review: z=0.0043； 16.3Mpc (Macri et al. 1999) radio(e.g., Owen et al. 1989; Biretta et al. 1995; Sparks et al. 1996; Zhou 1998), optical (e.g. Perlman et al. 2001a, Biretta et al. 1991), UV (Waters & Zepf, 2005 [WZ05]), X-ray(e.g., Marshall et al. 2002, Wilson & Yang 2002), Future High X-ray? The predicated Tev gamma-ray(Bai & Lee 2001 first) and the possible position where the TeV emission from the M87 (Georganopoulos et al. 2005; Cheung et al. 2007) have also been confirmed at a high cofidence level by the HESS observations (Aharonian et al. 2003 & 2006). Spins of the SMBH in M87: New Constrains from TeV observations(Wang et al. 2008, ApJ Letters, 676, L109). Especially Perlman & Wilson 2005 [PW05], analyzed diagnostics and physical interpretation of the X-ray emissions from the M87 jet. Many other observations have been done, such as photometric surveys of the jet, polarimetry maps of the jet (Perlman et al. 1999).

  4. Tri-band ComparisonImage Harris & Krawczynski 2006 http://chandra.harvard.edu/photo/2001/0134/m87comp_nolabels.jpg

  5. with the viewing angle of M87 jet (30-35 degree, Tsvetanov et al. 1998 and references therein) and apparent superluminal motions of M87 optical jet (Biretta et al. 1995), We could derive that the local velocities of some components in the M87 jet may be close to the light-speed. http://www.stsci.edu/ftp/science/m87/m87.html

  6. Liu & Shen 2007 (LS07) • A synchrotron origin for the X-ray emission.

  7. Tri-Model Fitting to M87 Knots (WZ05) • 1.KP(Kardashev 1962, hereafter K62;Pacholczyk 1970) assumes that the source of the emission is a single burst of energetic electrons with an isotropic pitch-angle distribution and thus no scatters. Because of the likely scattering of relativistic particles by hydromagnetic waves (e.g., Wentzel 1977), the KP model is physically unreasonable, and therefore will not be mentioned further in this paper. PW05

  8. Tri-Model Fitting to M87 Knots (WZ05) • 2.JP(Jaffe & Perola 1973) assumes the same initial conditions as those of the KP model, but allows scattering in the pitch-angle distribution so that it can maintain an isotropic distribution all the time. The resulting spectrum is an essentially exponential rollover above the synchrotron loss break frequency. • Without considering the X-ray data, the exponential high-energy rollover of JP model underpredicts the X-ray flux by many orders of magnitude and the slope at X-ray is much larger than the observed. PW05

  9. Tri-Model Fitting to M87 Knots (WZ05) • 3.CI(K62; Heavens & Meisenheimer 1987, hereafter HM87) assume that a power law distribution of relativistic particles is being continuously added to the emitting region, but the CI model of HM87 further takes the advective transport of the accelerated electrons downstream into account. The CI model of K62 has the similar spectral shape to the one of HM87. • Without considering the X-ray data the predicted X-ray flux by the CI model is higher than the observed one, the slope at X-ray is smaller than the observed. • The CI model is the most possible model among them. • PW05 Volume model，Why so coincidentfor index of X-ray spectrum? PW05

  10. Plot zooming in on the optical and UV region, where most of the data points are and also where most of the curvature is. LS07

  11. Constraints • The three standard models can’t fit the X-ray flux and the spectral index at X-ray under the single index of the electron energy spectrum at injection and single emission process.We summarize the criteriafor fitting the SEDs of the knots in the M87 jet discussed inWZ05 and PW05: • 1, the first break frequency should be under the UV turnover especially, for knots D, A, and B; • 2, a steeper X-ray spectral index than the optical isneeded, so there may be a second break frequency between UV data and X-ray data; • 3, the best fitting model should explain the flux and index (1.2 jump to 1.7) of the X-ray data as well as the onesof the radio, optical and UV data. LS07

  12. A Modified CI Model(MCI Model: Pipe-Reservoir Model) Hidden Rule: the acceleration region is the same as the main emission region!A specific but more general scenario may be: the main acceleration region and the main emission region are not strictly co-spatial! LS07

  13. - Main Acceleration Region: water pipe +Main Emission Region: reservior Channel/Pipe (further identification) Dermer 1995 Modified CI Model Obtained from Marshall et al. 2002 IHEP SHAO It may reflect the physical scenario of PW05 (Volume Model).

  14. LS07

  15. (ApJ Letters, 668, L27 (K07)) Pipe?

  16. Data LS07

  17. Fitting • We use the weighted least square method to fit our model to the wide-band data in each knot, in this progress a power law form is chosen near the break frequencies because we only need to concern the trend of the break frequencies. There are two peak frequencies in our model, but we don’t know where they are when we fit our model to the broadband data in each knot. So we first arbitrarily divide broadband data into three groups to perform the least chi square method, we could calculate the corresponding reduce chi square by changing the division. All the possible combinations are considered before we obtain the best fit with a minimal chi^2 among them. These best-fit parameters for each knot, are listed in Table 2. The SEDs for the knots in the M87 jet and the best fits for our model are plotted in Fig 1. LS07

  18. LS07

  19. LS07

  20. Results and Discussion • It satisfies the aforementioned three constraints for the SED of the knots of M87 jet (as shown in Fig 1 and Table 2). • The predicted spectra shapeof knots from UV to X-ray (from −p/2 to −(p+1)/2) could be tested by future telescope in the band. • According to the unified scheme of AGNs and equation (1) in Bai & Lee (2001), the Compton components from these knots will peak at 0.01 ∼ 1 GeV, and their flux densities at TeV would be undetectable (based on the synchrotron self-Compton model and the equation (4) in Bai & Lee 2001). This implies that the knots D, E, F, A, B, and C1 are unlikely to be the candidate for TeV emission in the M87 detected by the HESS observations (Aharonian et al. 2003 & 2006). The possible candidate for the TeV emission in M87 is related to the innermost region of M87 like HST-1 (peak close to TeV) or core itself (Stawarz et al. 2006; Aharonian et al. 2006 (need a large Doppler factor for G-G pair production (K07)); Cheung et al. 2007 (need an unrealistically small opening angle for the energy source, assuming the source was long located at the base of the jet (K07); pipe source could?). LS07

  21. We find that the value of the particle spectral index p is about 2.36 on average, which agrees well with the latest expectations from both diffusive shock acceleration theory (2.0-2.5, Kirk & Dendy 2001) and acceleration by relativistic shocks (2.23 in the ultrarelativistic limit, Kirk 2002). • From Table 2, as a whole the second break frequency decreases along the jet. This may imply that the synchrotron loss in the acceleration region will increase along the jet. (Pipe across whole jet?) (Our model is different from Spine-Sheath Model: Reservior from Pipe) • Our model still need to be further verified by future observations (high sensitivity and resolution). LS07

  22. (Fleishman’ PPT 12/16/05) Future work • 1. The radio-ultraviolet spectra of the jet in 3C 273 (Liu & Shen 2008, submission); other sources: 3C 345, OJ 287, BL Lac, 1308+32, 0235+16, W Com et al. • 2. Acceleration mechanism of the relativistic electrons in the M87 jet, especially HST-1 (IMPORTANT & INTERESTING). • 3. Flaring, variable: the numbers and intensities of sources in the acceleration region. Our Fitting shows that the Doppler factor of 3C273 Jet is 7.4 which well agrees with the requirement of FSRQ’s Doppler factor (>6.45, Cao & Bai 2008, ApJL). This may verify the Uniform Scheme on the correctness of quasars Category. And EC/CMB model may be responsible for high-energy emission (X-ray even to Gamma-ray) of the 3C 273 Jet. So, further promote this view, we think (and/or guess) that EC/CMB may be responsible for the Gamma-ray in the Radio Quasar (FRII) Jet downstream, with EC/CMB+BLR+Torus for the Gamma-ray in the Radio Quasar (FRII) Jet upstream (close to/in the Core), together with SSC for the Gamma-ray in the FRII Jet. This may explain the EGRB.

  23. Future work • 4. Uniform interpretation to both M87 and 3C 273 jets with our Pipe-Reservior Model which may be generally applicable to jets. Certainly, the Pipe still need to be identified by high sensitivity and resolution observatories (this may be easily identified for the jet with small viewing angle). Esp., there may exist apparent superluminal motions for the pipe in the jet. • 5. The relations between pipe and disc, core? Does the disc really exist? We may find a substitute for the disc. • 6. Jet Simulation, Esp. For M87 and 3C 273 Jets!!! (may be rough)

  24. Thanks http://t3.baidu.com/it/u=1737656413,1707304612&fm=0&gp=38.jpg If this PPT would be helpful for you, please citing Liu & Shen, 2007, ApJ Letters, 668, L23 . We thank the web authors of some cartoons in this PPT. http://www.shao.ac.cn/tianwu/group4/members/wpl.htm Wen-Po LIU, 2008.04.19, Personal Website Email: xiaopozi@163.com

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