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smaug: optically-thin, spherically-symmetric thermal plasma.

This model performs an analytical deprojection of an extended, optically-thin and spherically-symmetric source. A thorough description of the model is given in Pizzolato et al. (2003). In this model the 3D distributions of hydrogen, metals and temperature throughout the source are given specific functional forms dependent on a number of parameters, whose values are determined by the fitting procedure. The user has to extract the spectra in annular sectors, concentric about the emission peak. The inner boundary (in arcmin), the outer by the fitting procedure. The user has to extract the spectra in annular sectors, concentric about the emission peak. Three additional XFLTnnnn keywords must be added (e.g. with the ftools fkeypar). These should take the values “inner: x”, “outer: y”, “width: z” where x, y, z are the inner boundary (in arcmin), the outer boundary (also in arcmin), and the width (in degrees), respectively, of each annular sector. Some parameters of smaug define the redshift and other options (see below). The other, “relevant” ones define the 3D distributions of hydrogen density, temperature and metal abundance, determined by a simultaneous fit of the spectra. The cosmological parameters can be set using the cosmo command.

par1 central temperature [keV]
par2 max difference of temperature [keV]
par3 exponent of the inner temperature
par4 radius of the inner temperature [Mpc]
par5 exponent of the middle temperature
par6 radius of the middle temperature [Mpc]
par7 exponent of the outer temperature
par8 radius of the outer temperature [Mpc]
par9 central hydrogen density [cm$^{-3}$]
par10 fraction of nH.cc relative to the 1st beta component
par11 exponent of the first beta component
par12 radius of the 1st beta component [Mpc]
par13 exponent of the 2nd beta component
par14 radius of the 2nd beta component [Mpc]
par15 central metallicity [solar units]
par16 exponent of the metal distribution
par17 radius of the metal distribution [Mpc]
par18 redshift of the source
par19 number of mesh-points of the dem summation grid
par20 cutoff radius for the calculation [Mpc]
par21 mode of spectral evaluation: 0 = calculate, 1 = interpolate, 2 = APEC interpolate
par22 type of plasma emission code, 1 = Raymond-Smith, 2 = Mekal, 3 = Meka, 4 = APEC
K model normalisation (nH.cc squared [cm$^{-6}$] )

Note that if the interactive chattiness level in XSPEC is set to a value >10, smaug also prints on screen the following quantities:

H$_0$ Hubble constant [km/s/Mpc]
q$_0$ deceleration parameter
L$_0$ cosmological constant
DA source angular distance [Mpc]
DSET dataset no. to which the quantities listed below are
IN inner rim of the projected annular sector [Mpc]
OUT outer rim of the projected annular sector [Mpc]
WID width of the projected annular sector [deg]
EVOL emitting volume within the integration radius cutoff [Mpc$^3$]
EINT emission integral within the integration radius cutoff [ Mpc$^3$/cm$^6$]. If nH.cc is frozen to 1, the actual EI is obtained by multiplying this figure by the square root of the model normalisation
next up previous contents
Next: snapec, bsnapec: galaxy cluster Up: Additive Model Components Previous: slimbh: Stationary slim accretion   Contents