The Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center (GSFC) seeks a creative, innovative individual with strong teamwork and leadership skills to serve as Director of the High Energy Astrophysics Science Archive Research Center (HEASARC). This will be a permanent civil servant position. + Learn more.
zdust: extinction by dust grains
Extinction by dust grains from Pei (1992), suitable for IR,
optical and UV energy bands, including the full energy ranges of the Swift
UVOT and XMM-Newton OM detectors. Three models are included which
characterize the extinction curves of (1) the Milky Way, (2) the LMC and
(3) the SMC. The models can be modified by redshift and can therefore be
applied to extragalactic sources. The transmission is set to unity shortward
of 912 Angstroms in the rest frame of the dust. This is incorrect physically
but does allow the model to be used in combination with an X-ray photoelectric
absorption model such as phabs. Parameter 1 (method) describes
which extinction curve (MW, LMC or SMC) will be constructed and should
never be allowed to float during a fit. The extinction at V, A(V) =
E(B-V) x Rv. Rv should typically remain frozen for a fit. Standard values
for Rv are MW = 3.08, LMC = 3.16 and SMC = 2.93 (from table 2 of Pei 1992),
although these may not be applicable to more distant dusty sources.
par1 |
method: 1 = Milky Way, 2 = LMC, 3 = SMC |
par2 |
E(B-V): color excess |
par3 |
Rv: ratio of total to selective extinction |
par4 |
z: redshift |
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Last modified: Friday, 23-Aug-2024 13:20:40 EDT
The Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center (GSFC) seeks a creative, innovative individual with strong teamwork and leadership skills to serve as Director of the High Energy Astrophysics Science Archive Research Center (HEASARC). This will be a permanent civil servant position. + Learn more.
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