Le morfogenesi della Costituzione nell'epoca della globalizzazione

Emitting Electron Spectra and Acceleration Processes in the Jet of PKS 0447-439

“…In this work, we adopt the quasi-simultaneous SED of PKS 0447-439 reported in Prandini et al (2012), which includes the Swift/UVOT, Swift/XRT, Fermi/LAT and H.E.S.S. data observed during November 2009 -January 2010.…”

“…In our fittings, we fix γ ′ min = 400 and γ ′ max = 10 8 for the three cases. Meanwhile, we use t v,min = 1 day as its upper limit because of a signature of variability at X-ray energies on timescale of one day (Prandini et al 2012). We also set an upper limit for Doppler factor, δ D ≤ 50 to avoid the extreme value.…”

“…Therefore, the redshift obtained in this case is incredible. For the LP case, since we fix the electron energy index s = 2.0 according to the result of Prandini et al (2012), there are also seven parameters, which are B, δ D , t v,min , r, γ ′ c , U ′ e /U ′ B and z (see Table 1). It can be seen that the fitting in this case becomes good (solid line in Fig.…”

“…campaign Swift observed PKS 0447-439 at optical-X-ray bands for about one week (Abramowski et al 2013). Therefore, a highquality multi-band SED has been built (Prandini et al 2012;Abramowski et al 2013). However, the redshift of PKS 0447-439 is not determined so far due to its weak emission lines.…”

“…Recently, Landt et al (2012) put a high lower limit of z > 1.246 based on the weak absorption lines which however was defined as atmospheric absorption lines by the detection of Pita et al (2012). On the other hand, the redshift of PKS 0447-439 can be estimated through combining its observed GeV-TeV spectrum, for example, Prandini et al (2012) suggested that its redshift is likely 0.2, and Abramowski et al (2013) pointed out that the most conservative upper limit of this obect is z < 0.59.…”