Query the ESPRESSO ETC

etc.py

import re
import requests
from itertools import product
import numpy as np

url = 'https://www.eso.org/observing/etc/bin/simu/espresso'


form_data = {
    'almanac_time_option': 'almanac_time_option_ut_time',
    'COORD.DEC': '00:00:00',
    'COORD.RA': '04:00:00',
    'INS.DET.EXP.TIME.VAL': '30.000',
    'INS.ESPRESSO.MODE': 'single_HR_1x1_fast',
    'INS.FEED.UT.COUNT': '1',
    'INS.GEN.TABLE.RES.SWITCH.VAL': 'yes',
    'INS.GEN.TABLE.SF.SWITCH.VAL': 'yes',
    'INS.MODE': 'spectro',
    'INS.NAME': 'ESPRESSO',
    'POSTFILE.FLAG': '0',
    'RESULT.RV.PRECISION.FLAG': '1',
    'SKY.AIRMASS': '1.5',
    'SKY.MOON.FLI': '0.5',
    'SKY.SEEING.ZENITH.V': '1.00',
    'SKYMODEL.ECL.LAT': '90',
    'SKYMODEL.ECL.LON': '135',
    'SKYMODEL.INCL.AIRGLOW': 'Y',
    'SKYMODEL.INCL.MOLEC.EMIS.LOWER.ATM': 'Y',
    'SKYMODEL.INCL.MOLEC.EMIS.UPPER.ATM': 'Y',
    'SKYMODEL.INCL.MOON': 'Y',
    'SKYMODEL.INCL.STARLIGHT': 'Y',
    'SKYMODEL.INCL.THERMAL': 'N',
    'SKYMODEL.INCL.ZODIACAL': 'Y',
    'SKYMODEL.MOON.ALT': '45',
    'SKYMODEL.MOON.EARTH.DIST': '1',
    'SKYMODEL.MOON.SUN.SEP': '90.000',
    'SKYMODEL.MOON.TARGET.SEP': '45',
    'SKYMODEL.MSOLFLUX': '130.00',
    'SKYMODEL.PWV.MODE': 'pwv',
    'SKYMODEL.SEASON': '0',
    'SKYMODEL.TARGET.ALT': '90.000',
    'SKYMODEL.THERMAL.E1': '0.20',
    'SKYMODEL.THERMAL.E2': '0.10',
    'SKYMODEL.THERMAL.E3': '0.01',
    'SKYMODEL.THERMAL.T1': '+285.0',
    'SKYMODEL.THERMAL.T2': '+288.0',
    'SKYMODEL.THERMAL.T3': '++33.0',
    'SKYMODEL.TIME': '0',
    'SRC.TARGET.GEOM': 'seeing_ltd',
    'SRC.TARGET.MAG': '7.00',
    'SRC.TARGET.MAG.BAND': 'V',
    'SRC.TARGET.MAG.SYSTEM': 'Vega',
    'SRC.TARGET.REDSHIFT': '0.00',
    'SRC.TARGET.SPEC.TYPE': 'Kurucz_G2V',
    'SRC.TARGET.TYPE': 'template_spectrum',
    'step_size': '1',
    'toggleTables': 'on',
    'USR.SEEING.OR.IQ': 'seeing_given',
    'USR.SESSION.ID': 'non-init',
    'ut_time': '07/12/2018+03:04:08',
}



def query(exptime=30, Vmag=7, airmass=1.5):
    fill = form_data
    fill['INS.DET.EXP.TIME.VAL'] = str(exptime)
    fill['SRC.TARGET.MAG'] = str(Vmag)
    fill['SKY.AIRMASS'] = str(airmass)
    r = requests.post(url, data=fill)
    return r


def RVprecision(**kwargs):
    r = query(**kwargs)
    a = re.compile(r"[-+]?\d*\.\d+ m/s")
    precision = re.findall(a, r.text)[0]
    return precision


grid = product(
               np.linspace(1, 1.5, 10), # airmass grid
               np.linspace(5, 11, 10),  # Vmag grid 
               )


for airmass, Vmag in grid:
    print(f'airmass: {airmass:>6.3f} Vmag: {Vmag:>6.3f}', end=' - ')
    precision = RVprecision(exptime=900, Vmag=Vmag, airmass=airmass)
    print(f'{precision:10s}')