Theory parameter definitions
Table describing the variables used to specify theory choices in nnpdf. Here they are shown
directly as the fields of the runcards in theory_cards.
The Type column refers directly to data type of the field.
Field/key |
Type |
Description |
Comments |
|---|---|---|---|
ID |
Integer |
TheoryID |
Theory enumerating ID |
PTO |
Integer |
pQCD order |
(0/1/2 = LO/NLO/NNLO) |
FNS |
Text |
Flavour Number Scheme |
e.g FONLL-A/B/C, ZM-VFNS or FFNS |
DAMP |
Integer |
FONLL damping factor switch |
Boolean |
IC |
Integer |
Intrinsic charm switch |
Boolean |
ModEv |
Text |
DGLAP solution mode |
EXA/EXP/TRN |
XIR |
Real |
\(\xi_R\) |
\(\mu_R/Q\) |
XIF |
Real |
\(\xi_F\) |
\(\mu_F/Q\) |
NfFF |
Integer |
Number of flavours in the FFNS |
3/4/5/6 |
MaxNfAs |
Integer |
\(n^{(\alpha_s)}_{f \textrm{max}}\) |
Max active flavours in \(\alpha_s\) |
MaxNfPdf |
Integer |
\(n^{(PDF)}_{f \textrm{max}}\) |
Max active flavours in PDFs |
Q0 |
Real |
\(Q_0\) |
FK Table initial scale |
alphas |
Real |
Strong coupling |
Format: \(\alpha_s(Q_{\textrm{ref}})\) |
Qref |
Real |
\(Q_{\textrm{ref}}\) |
Reference scale for \(\alpha_S\) in GeV |
QED |
Integer |
QED switch |
Boolean |
alphaqed |
Real |
QED coupling |
Format: \(\alpha_{QED}(Q_{\textrm{qedref}})\) |
Qedref |
Real |
\(Q_{\textrm{qedref}}\) |
QED reference scale (GeV) |
SxRes |
Integer |
small-\(x\) resummation switch |
Boolean |
SxOrd |
Text |
small-\(x\) pt switch |
(‘LL’, ‘NLL’, ‘NLL’) |
HQ |
Text |
HQ mass treatment |
POLE/MSBAR |
mc |
Real |
\(c\) quark mass \(M_c/m_c(Q_{mc})\) |
Units: GeV |
Qmc |
Real |
\(Q_{mc}\) |
\(c\) reference scale (GeV) |
kcThr |
Real |
\(c\) production threshold ratio |
Ratio to \(m_c\) |
mb |
Real |
\(b\) quark mass \(M_b/m_b(Q_{mb})\) |
Units: GeV |
Qmb |
Real |
\(Q_{mb}\) |
\(b\) reference scale (GeV) |
kbThr |
Real |
\(b\) production threshold ratio |
Ratio to \(m_b\) |
mt |
Real |
\(t\) quark mass \(M_t/m_t(Q_{mt})\) |
Units: GeV |
Qmt |
Real |
\(Q_{mt}\) |
\(t\) reference scale (GeV) |
ktThr |
Real |
\(t\) production threshold ratio |
Ratio to \(m_t\) |
CKM |
Text |
CKM matrix elements |
Unpacked 3X3 matrix |
MZ |
Real |
\(M_Z\) |
\(Z\) mass (GeV) |
MW |
Real |
\(M_W\) |
\(W\) mass (GeV) |
GF |
Real |
\(G_F\) |
Fermi coupling constant |
SIN2TW |
Real |
\(\sin^2\theta_W\) |
|
TMC |
Integer |
Target mass corrections |
Boolean |
MP |
Real |
\(M_P\) Proton mass |
Units: GeV |
global_nx |
Integer |
Global x-grid precision |
Default (0) uses set-by-set precision |
EScaleVar |
Real |
Switch for DGLAP scale variation |
Boolean |
Comments |
Text |
General comments |