Attachment 'NIKA2_Time_Estimator.py'
Download 1 #!/usr/bin/env python
2 ##############################################################################################
3 ### Created by: P. Garcia ###
4 ### Last update: A. Ritacco ###
5 ### Title: NIKA2_Time_Estimator.py ###
6 ### Purpose: Calculation of the total integration time for observing proposals ###
7 ### Creation Date: 2016.JULY.28 ###
8 ### Date of last revision: 2017.JAN.29 ###
9 ### Revision history: ###
10 ### - 2016.JULY.29: comments from C. Kramer & A. Sievers implemented ###
11 ### - 2016.AUG.03 : changed formula to N. Billot expression ###
12 ### - 2017.JAN.29 : - fpix set to 0.75 (commisi. results) ###
13 ### - NEFD0 @ 2 mm set to 15 mJy/sqrt(hz) (commisi. results) ###
14 ### - overhead set as used defined parameter between 1.5 - 2.0 ###
15 ### - 2017.JULY.28: - According to the NIKA2 technical paper submitted on July, 3rd 2017 ###
16 ### - fpix @1mm, 2mm set to 0.84 and 0.90, respectively ###
17 ### - NEFD0 @1mm, 2mm set to 20 and 6 mJy/sqrt(hz), respectively ###
18 ### - FWHM set to 11.2 @1mm and 17.7 @2mm ###
19 ##############################################################################################
20
21 import numpy as np, sys
22 import math
23 import sys
24 import os
25 os.system("rm -f *.py~")
26
27 #version = 'v 2017.JAN.29'
28 version = 'v 2017.JULY.28'
29
30
31 class bcolors:
32 HEADER = '\033[95m'
33 OKBLUE = '\033[94m'
34 OKGREEN = '\033[92m'
35 WARNING = '\033[93m'
36 FAIL = '\033[91m'
37 ENDC = '\033[0m'
38 BOLD = '\033[1m'
39 UNDERLINE = '\033[4m'
40
41 print ''
42 print bcolors.UNDERLINE + bcolors.HEADER + bcolors.BOLD + 'Time-estimator-NIKA2 '+version+' '+bcolors.ENDC
43 print ''
44 print bcolors.HEADER + bcolors.BOLD + ' See the "Guidelines for observing time estimates with the NIKA2 continuum camera' + bcolors.ENDC
45 print bcolors.HEADER + bcolors.BOLD + ' at the IRAM-30m Telescope" for details on used parameters and calculations.\n' + bcolors.ENDC
46
47 ################################
48 ##### CONVERSION FACTORS #######
49 ################################
50
51 ########## K_cmb ############
52 def b_v_cmb(freq,tcmb):
53 h = 6.626070040*10**(-34) # (J.s) Planck constant
54 k = 1.38064852*10**(-23) # (J/K) Boltzmann constant
55 c = 299792458 # (m/s^2) light speed
56 freq = freq*10**9 # Hz
57 bv = 1.0/(((2*h*freq**3)/((c**2)*(np.e**((h*freq)/(k*tcmb)) - 1)))*(np.e**((h*freq)/(k*tcmb))/(np.e**((h*freq)/(k*tcmb)) - 1))*(h*freq/(k*tcmb**2))) / 10**20
58 return bv
59
60 ########## Ysz ##############
61 def y_sz(freq,tcmb):
62 h = 6.626070040*10**(-34) # (J.s) Planck constant
63 k = 1.38064852*10**(-23) # (J/K) Boltzmann constant
64 c = 299792458 # (m/s^2) light speed
65 freq = freq*10**9 # Hz
66 Ysz = 1.0
67 bv = 1.0/(((2*h*freq**3)/((c**2)*(np.e**((h*freq)/(k*tcmb)) - 1)))*(np.e**((h*freq)/(k*tcmb))/(np.e**((h*freq)/(k*tcmb)) - 1))*(h*freq/(k*tcmb**2)))
68 bv = 1.0/bv
69 y_sz = (bv*tcmb)*(((h*freq/(k*tcmb))*((np.e**((h*freq)/(k*tcmb)) + 1)/(np.e**((h*freq)/(k*tcmb)) -1))) -4)*Ysz /10**(-20)
70 y_sz = 1.0/y_sz
71 return y_sz
72
73 #%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
74 #%%%%%%%%%%%%%%%%%%%%% FIXED GENERAL PARAMETERS %%%%%%%%%%%%%%%%%%%%%%
75 #%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
76
77 ################################################
78 ##### BEAM SIZES AND CONVERSION TO RADIANS #####
79 ################################################
80 res_band1_spec = 11.2 #From NIKA2 1st paper #MEMO # 12.0 # [arcsec]
81 res_band2_spec = 17.7 #From NIKA2 1st paper #MEMO # 20.0 # [arcsec]
82 teta_band1_spec = res_band1_spec*math.pi/180.0/3600.0 # in sr units
83 teta_band2_spec = res_band2_spec*math.pi/180.0/3600.0 # in sr units
84 area_teta_band1_spec = ((teta_band1_spec/2.0)**2)*math.pi # in sr units
85 area_teta_band2_spec = ((teta_band2_spec/2.0)**2)*math.pi # in sr units
86 ############################
87 ##### OTHER PARAMETERS #####
88 ############################
89 #fpix_spec = 0.75
90 fpix_spec_1mm = 0.84
91 fpix_spec_2mm = 0.90
92 bv_1 = 0.075 # band1, do not change
93 cv_1 = 0.001 # band1, do not change
94 bv_2 = 0.025 # band2, do not change
95 cv_2 = 0.001 # band2, do not change
96 tiempo = 1.0 # [hours]
97 FoV = 6.5 # [arcmin] diameter
98 FoVArea = ((FoV/2.0)**2)*math.pi # [arcmin^2]
99 narrays1 = 2
100 narrays2 = 1
101 verbose_flag = 0
102 #foverhead = 2.0 # value fixed for all proposals in 2016
103 ##########################################
104 ##### NEFDo VALUES FROM OBSERVATIONS #####
105 ##########################################
106 NEFD_band1_spec = 20 #From NIKA2 1st paper #30 #MEMO
107 NEFD_band2_spec = 6 #From NIKA2 1st pape #15 #comissioning results 2016
108 #######################################
109 ##### SAMPLING ANGULAR VELOCITIES #####
110 #######################################
111 sampl_vel_fast = 48.0 # [arcsec/second]
112 sampl_vel_mid = 24.0 # [arcsec/second]
113 sampl_vel_slow = 12.0 # [arcsec/second]
114 sampl_rate = 23.84 # [hz]
115 sampl_rate_pol = 2*23.84 # [hz]
116 slewing_loss = 1.0 # to account for slewing of single OTF line
117 ##########################################
118 ##########################################
119 ##########################################
120
121 rango = len(sys.argv)
122 for i in range(rango):
123
124 if sys.argv[i] == ("--help") or rango == 1:
125
126 print ' USAGE:\n'
127 print ' python NIKA2_Time_Estimator.py --help '
128 print ' python NIKA2_Time_Estimator.py --band 1 --rms 2.00 --pwv 2 --elevation 40 --Xsize 2 --Ysize 2 --filter 1.0 --overhead 1.5'
129 print ' python NIKA2_Time_Estimator.py --band 2 --rms 1.00 --pwv 4 --elevation 50 --Xsize 15 --Ysize 15 --filter 2.0 --overhead 2.0 --verbose '
130 print '\n'
131 print ' OPTIONS:\n'
132 print ' help => This help.'
133 print ' band => Set 1 or 2 for the 1 mm or the 2 mm bands, respectively.'
134 print ' rms => Wanted flux density per beam. Any value above the confusion limit in [mJy/beam].'
135 print ' pwv => Precipitable water vapor in [mm].'
136 print ' elevation => Values from 15 to < 83 [deg].'
137 print ' Xsize Ysize => Map lengths. Xsize and Ysize are in [arcmin]. Minimum map size is 2x2 [arcmin^2] for homogeneous RMS noise distribution.'
138 print ' filter => Factor for post-processing noise filtering. Values from 1.0 (point-like source) to 2.0 (extended bright emission).'
139 print ' overhead => Factor for telescope overheads between 1.5 and 2.0 (slewing, pointing, focusing, calibration), i.e. all telescope time which is not spend integrating on-source.'
140 print ' verbose => Set to get list of parameters used in the calculations, RMS noise unit conversion, and allowed OTF scan speeds.\n'
141 sys.exit()
142
143 if sys.argv[i] == ("--band"):
144 band = int(sys.argv[i+1])
145 if band == 1:
146 narrays = narrays1
147 mili = 1.2
148 if band == 2:
149 narrays = narrays2
150 mili = 2.0
151 if band < 1 or band > 2:
152 print ' %%%%%%%%%%%%%%%%%%%%%%%'
153 print bcolors.BOLD + bcolors.FAIL +' Band %2i is not defined.' % (band) + bcolors.ENDC
154 print ' %%%%%%%%%%%%%%%%%%%%%%%'
155 print ''
156 sys.exit()
157
158 if sys.argv[i] == ("--rms"):
159 rms = float(sys.argv[i+1])
160
161 if sys.argv[i] == ("--pwv"):
162 pwv = float(sys.argv[i+1])
163
164 if sys.argv[i] == ("--elevation"):
165 elevation = float(sys.argv[i+1])
166 if elevation < 15 or elevation > 83:
167 print ' %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
168 print bcolors.BOLD + bcolors.FAIL +' Elevation %3i [degrees] is outside the telescope`s limits: 15 - 83 [degrees].' % (elevation) + bcolors.ENDC
169 print ' %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
170 print ''
171 sys.exit()
172
173 if sys.argv[i] == ("--Xsize"):
174 dx = float(sys.argv[i+1])
175
176 if sys.argv[i] == ("--Ysize"):
177 dy = float(sys.argv[i+1])
178
179 if sys.argv[i] == ("--filter"):
180 filtering = float(sys.argv[i+1])
181 if filtering < 1 or filtering > 2:
182 print ' %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
183 print bcolors.BOLD + bcolors.FAIL +' Filter value %2.1f is outside the standard limits: 1.0 - 2.0' % (filtering) + bcolors.ENDC
184 print ' %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
185 print ''
186 sys.exit()
187
188 if sys.argv[i] == ("--overhead"):
189 foverhead = float(sys.argv[i+1])
190 if foverhead < 1.5 or foverhead > 2:
191 print ' %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
192 print bcolors.BOLD + bcolors.FAIL +' Overhead value %2.1f is outside the standard limits: 1.5 - 2.0' % (foverhead) + bcolors.ENDC
193 print ' %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
194 print ''
195 sys.exit()
196
197 if sys.argv[i] == ("--verbose"):
198 verbose_flag = 1
199
200 area_obs = dx*dy
201
202 if area_obs < 4.0:
203 print ' %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
204 print bcolors.BOLD + bcolors.FAIL +' Introduced map size is %3.1f [arcmin^2]. Minimum value is 4.0 [arcmin^2]' % (area_obs) + bcolors.ENDC
205 print ' %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
206 print ''
207 sys.exit()
208
209 ###############################################################################################
210 ### SIGMA ESTIMATION CALCULATION, EFFECTIVE NEFD FROM PWV GIVEN VALUES AND UNITS CONVERSION ###
211 ###############################################################################################
212
213 if band == 1:
214 tau = bv_1*pwv + cv_1
215 NEFD_spec_eff = NEFD_band1_spec*(np.e**(tau/np.sin(elevation*math.pi/180.)))
216 rms_point_MJy_spec = rms/area_teta_band1_spec/10**9
217 rms_point_cmb_spec = rms_point_MJy_spec*b_v_cmb(260,2.726)*10**6
218 rms_point_ys_spec = rms_point_MJy_spec*y_sz(260,2.726)*10**6
219 rms_point_ys_spec = np.abs(rms_point_ys_spec)
220 #########################################
221 ### ratio of areas with fraction of valid pixel in the 2mm band ###
222 #########################################
223 factor_area_spec = (1+(area_obs/(FoVArea*fpix_spec_1mm))) # from N. Billot Doc.
224 ##########################################################
225 ### Integration Time calculations for given conditions ###
226 ##########################################################
227 t_spec = ((NEFD_spec_eff*filtering/rms)**2)*factor_area_spec*(foverhead)/3600.0 #hours
228 s_map_spec = ((dx*dy)/(((NEFD_spec_eff*filtering)**2)*foverhead))*3600.0 # arcmin^2 / hour^-1/ mJy^-2
229 if band == 2:
230 tau = bv_2*pwv + cv_2
231 NEFD_spec_eff = NEFD_band2_spec*(np.e**(tau/np.sin(elevation*math.pi/180.)))
232 rms_point_MJy_spec = rms/area_teta_band2_spec/10**9
233 rms_point_cmb_spec = rms_point_MJy_spec*b_v_cmb(150,2.726)*10**6
234 rms_point_ys_spec = rms_point_MJy_spec*y_sz(150,2.726)*10**6
235 rms_point_ys_spec = np.abs(rms_point_ys_spec)
236 #########################################
237 ### ratio of areas with fraction of valid pixel in the 2mm band ###
238 #########################################
239 factor_area_spec = (1+(area_obs/(FoVArea*fpix_spec_2mm))) # from N. Billot Doc.
240 ##########################################################
241 ### Integration Time calculations for given conditions ###
242 ##########################################################
243 t_spec = ((NEFD_spec_eff*filtering/rms)**2)*factor_area_spec*(foverhead)/3600.0 #hours
244 s_map_spec = ((dx*dy)/(((NEFD_spec_eff*filtering)**2)*foverhead))*3600.0 # arcmin^2 / hour^-1/ mJy^-2
245
246 #########################################
247 #### TIME PER OTF LINE TO REACH TOTAL ###
248 #########################################
249
250 T_SLOW = slewing_loss*((dx*60.0)/sampl_vel_slow)/60.0 # [minutes]
251 T_MID = slewing_loss*((dx*60.0)/sampl_vel_mid)/60.0 # [minutes]
252 T_FAST = slewing_loss*((dx*60.0)/sampl_vel_fast)/60.0 # [minutes]
253
254 if verbose_flag == 1:
255
256 print ''
257 print '%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
258 print '%%%%%%%%%% General Parameters Used for the Calculations %%%%%%%%%%%'
259 print '%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
260 print ''
261 print '------------------------------------------------------------------------'
262 print '| Parameters | Band 1 (1.2 mm) | Band 2 (2.0 mm) |'
263 print '------------------------------------------------------------------------'
264 print '| opacity | %6.3fxpwv + %6.3f | %6.3fxpwv + %6.3f |' % (bv_1,cv_1,bv_2,cv_2)
265 print '------------------------------------------------------------------------'
266 print '| HPBW [arcsec] | %6.1f | %6.1f |' % (res_band1_spec,res_band2_spec)
267 print '------------------------------------------------------------------------'
268 print '| NEFDo [mJy.s^0.5] | %6.1f | %6.1f |' % (NEFD_band1_spec,NEFD_band2_spec)
269 print '------------------------------------------------------------------------'
270 print '| fpix | %6.2f | %6.2f |' % (fpix_spec_1mm, fpix_spec_2mm)
271 print '------------------------------------------------------------------------'
272 if band == 1:
273 print '| rms [mJy/beam] | %6.2f | |' % (rms)
274 if band == 2:
275 print '| rms [mJy/beam] | | %6.2f |' % (rms)
276 print '------------------------------------------------------------------------'
277 print '| FoV [arcmin] | %6.1f |' % (FoV)
278 print '------------------------------------------------------------------------'
279 print '| h-filtering | %6.2f |' % (filtering)
280 print '------------------------------------------------------------------------'
281 print '| h-overhead | %6.2f |' % (foverhead)
282 print '------------------------------------------------------------------------'
283 print '| OTF slow [arcsec/s] | %4i |' % (sampl_vel_slow)
284 print '------------------------------------------------------------------------'
285 print '| OTF mid [arcsec/s] | %4i |' % (sampl_vel_mid)
286 print '------------------------------------------------------------------------'
287 print '| OTF fast [arcsec/s] | %4i |' % (sampl_vel_fast)
288 print '------------------------------------------------------------------------'
289 print '| Dump [hz] | %6.2f |' % (sampl_rate)
290 print '------------------------------------------------------------------------'
291 print '| Dump POL [hz] | %6.2f |' % (sampl_rate_pol)
292 print '------------------------------------------------------------------------'
293 print ''
294
295 print ' %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
296 print ' %%%%%%%%%%%%%%%%% Units Conversion %%%%%%%%%%%%%%%%%'
297 print ' %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
298 print ''
299 print ' --------------------------------------------------------'
300 print ' | (User Defined) | Band %1i |' % (band)
301 print ' --------------------------------------------------------'
302 print ' |rms [mJy/beam] | %8.2f |' % (rms)
303 print ' --------------------------------------------------------'
304 print ' |rms point-like source [MJy/sr] | %6.2f |' % (rms_point_MJy_spec)
305 print ' |rms point-like source [K_CMB]x10^-6 | %5i |' % (rms_point_cmb_spec)
306 print ' |*rms point.like source [Ysz]x10^-6 | %5i |' % (rms_point_ys_spec)
307 print ' --------------------------------------------------------'
308 print ' |* for Ysz = 1.0 |'
309 print ' --------------------------------------------------------'
310 print ''
311
312
313 #############################
314 #### TABLE FINAL RESULTS ####
315 #############################
316
317 print ' %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
318 print ' %%%%%%%%%%%%%%%%%%%%%% Results %%%%%%%%%%%%%%%%%%%%%%'
319 print ' %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
320 print ''
321 print ' for: El = %2i (deg), PWV = %1i (mm), tau = %4.2f, rms = %6.2f' % (elevation,pwv,tau,rms)
322 print ' Area = %4.1f (arcmin^2), Filter = %4.1f, Overhead = %4.1f' % (area_obs,filtering,foverhead)
323 print ' ---------------------------------------------------------------'
324 print ' | (User Defined) | | |'
325 print ' ---------------------------------------------------------------'
326 print ' | Band | | %1i |' % (band)
327 print ' ---------------------------------------------------------------'
328 if band == 1:
329 print ' | Total Integration Time at 1mm | [hours] | %6.1f |' % (t_spec)
330 print ' ---------------------------------------------------------------'
331 print ' | Mapping speed | [arcmin^-2/hour/mJy^-2 ] | %6.1f |' % (s_map_spec)
332 if band == 2:
333 print ' | Total Integration Time at 2mm | [hours] | %6.1f |' % (t_spec)
334 print ' ---------------------------------------------------------------'
335 print ' | Mapping speed | [arcmin^-2/hour/mJy^-2 ] | %6.1f |' % (s_map_spec)
336 print ' ---------------------------------------------------------------'
337 print ' '
338
339 if verbose_flag == 1:
340
341 print bcolors.WARNING + ' WARNING1: For proposed maps taking longer than 40 minutes, the total'
342 print bcolors.WARNING + ' integration time should be split into several maps.\n' + bcolors.ENDC
343 print ' '
344 print bcolors.WARNING + ' WARNING2: Note that the confusion noise is not included in this Time'
345 print bcolors.WARNING + ' Estimator and it should be discussed in the proposal whether appro-'
346 print bcolors.WARNING + ' priate. The RMS noise does not decrease indefinitely with integra- '
347 print bcolors.WARNING + ' tion time but stops at the confusion limit caused by unresolved sour-'
348 print bcolors.WARNING + ' ces within the beam. The exact threshold at which the RMS noise '
349 print bcolors.WARNING + ' reaches the confusion limit will vary with wavelength, beam size, '
350 print bcolors.WARNING + ' and the type of astronomical source (Galactic or Extra-Galactic). For'
351 print bcolors.WARNING + ' instance, for the GOODS-N field (part of the Deep Field GT Proposal),'
352 print bcolors.WARNING + ' a preliminary 1 sigma confusion limit around ~ 0.090 mJy and ~ 0.056'
353 print bcolors.WARNING + ' mJy at 1.2 mm and 2.0 mm, respectively, has been estimated (A. Beelen,'
354 print bcolors.WARNING + ' private communication).\n' + bcolors.ENDC
355
356 print ' '
357 print ' Time per OTF line for allowed scanning speeds '
358 print ' -----------------------------------------------------'
359 print ' | | OTF Scan Velocity | TIME PER OTF LINE |'
360 print ' -----------------------------------------------------'
361 print ' | | [arcsec/s] | [minutes] |'
362 print ' -----------------------------------------------------'
363 print ' | OTF-SLOW | %6.1f | %6.2f |' % (sampl_vel_slow,T_SLOW)
364 print ' | OTF-MID | %6.1f | %6.2f |' % (sampl_vel_mid,T_MID)
365 print ' | OTF-FAST | %6.1f | %6.2f |' % (sampl_vel_fast,T_FAST)
366 print ' -----------------------------------------------------'
367 print ' '
368
369 ###############################
370 #### CONVERSION TO MINUTES ####
371 ###############################
372
373 if t_spec >= 1.:
374 time_str_spec=str(round(t_spec,1))+' hours'
375
376 if t_spec < 1. and t_spec >= 1./60.:
377 time_str_spec=str(round(t_spec*60,1))+' minutes'
378
379 if t_spec < 1./60. and t_spec >= 0.1/3600.:
380 time_str_spec=str(int(t_spec*3600))+' seconds'
381
382 if t_spec < 0.1/3600.:
383 time_str_spec='0.1 (seconds)'
384
385 slew_overhe = str(int((slewing_loss-1.0)*100.0))
386
387 ##############################
388 #### OUTPUT FINAL RESULTS ####
389 ##############################
390
391 print bcolors.HEADER + '**********************************************'
392 print '*** Total Integration Time => ' + time_str_spec + ' ***'
393 print '**********************************************\n'
394 print ''
395
396 print bcolors.HEADER + bcolors.UNDERLINE + 'Please include the following text into your proposal:\n' + bcolors.ENDC
397
398 print 'According to the specifications of the NIKA2 instrument, the total observing time using the NIKA2 '+str(band)+' mm band to map a region of '+str(round(area_obs,1))+' [arcmin^2] to reach an rms of '+str(rms)+' [mJy/beam], assuming '+str(pwv)+' [mm] pwv, '+str(elevation)+' [deg] elevation, Filter = '+str(filtering)+', Overhead = '+str(foverhead)+', was estimated to be *'+time_str_spec+'*, using the time estimator '+version+'.\n'
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