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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. (ApJ 592, 62, 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:

H0

Hubble constant [km/s/Mpc]

q0

deceleration parameter

L0

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 [Mpc3]

EINT

emission integral within the integration radius cutoff [ Mpc3 cm-6]. If nH.cc is frozen to 1, the actual EI is obtaned by multiplying this figure by the square root of the model normalisation

 

next up previous contents
Next: Srcut Up: Additive Model Components Previous: Sirf