[bug] PROFILE_LORENTZ uses the wrong sign for Delta0

[cexen]

In PROFILE_LORENTZ, the pressure shift Delta0 has the wrong sign.

Current implementation:

def PROFILE_LORENTZ(Nu,Gamma0,Delta0,WnGrid,YRosen=0.0,Sw=1.0):
    if YRosen==0.0:
        return Sw*Gamma0/(pi*(Gamma0**2+(WnGrid+Delta0-Nu)**2))
    else:
        return Sw*(Gamma0+YRosen*(WnGrid+Delta0-Nu))/(pi*(Gamma0**2+(WnGrid+Delta0-Nu)**2))

Expected (sign of Delta0 flipped):

def PROFILE_LORENTZ(Nu,Gamma0,Delta0,WnGrid,YRosen=0.0,Sw=1.0):
    if YRosen==0.0:
        return Sw*Gamma0/(pi*(Gamma0**2+(WnGrid-Delta0-Nu)**2))
    else:
        return Sw*(Gamma0+YRosen*(WnGrid-Delta0-Nu))/(pi*(Gamma0**2+(WnGrid-Delta0-Nu)**2))

Minimal Reproduction:

import hapi
import numpy as np

TABLE = "H₂¹⁶O"
hapi.db_begin("hapi_db")
hapi.fetch(TABLE, 1, 1, 3744.65, 3744.66)

nu = hapi.getColumn(TABLE, "nu")
delta = hapi.getColumn(TABLE, "delta_air")
assert len(nu) == 1
nu0 = nu[0]
delta_air = delta[0]
print(f"nu0 = {nu0}")
print(f"delta_air = {delta_air}")


def _run(fn, label):
    nu_out, coef = fn(
        SourceTables=TABLE,
        WavenumberRange=(nu0 - 0.05, nu0 + 0.05),
        WavenumberStep=0.000001,
    )
    peak = nu_out[np.argmax(coef)]
    shift = peak - nu0
    print(f"{label}: {peak:.6f} ({shift:+.6f})")


_run(hapi.absorptionCoefficient_Priority, "Priority")
_run(hapi.absorptionCoefficient_HT, "HT")
_run(hapi.absorptionCoefficient_SDVoigt, "SDVoigt")
_run(hapi.absorptionCoefficient_Voigt, "Voigt")
_run(hapi.absorptionCoefficient_Lorentz, "Lorentz")
_run(hapi.absorptionCoefficient_Doppler, "Doppler")

Output (excerpt):

nu0 = 3744.651222
delta_air = -0.005164

Priority: 3744.646058 (-0.005164)
HT: 3744.646058 (-0.005164)
SDVoigt: 3744.646058 (-0.005164)
Voigt: 3744.646058 (-0.005164)
Lorentz: 3744.656386 (+0.005164)
Doppler: 3744.651222 (-0.000000)

Lorentz shifts in the opposite direction.