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Data table for comparison of JWST photometric sensitivity to other observatories. v1.4, 10/2014

# Data table for comparison of JWST photometric sensitivity to other observatories. 
# v1.4, 10/2014, by Jane Rigby.
# If you have comments or questions, please write to Jane.R.Rigby@nasa.gov
# Columns are:  
#  (1) name of filter and/or band
#  (2) wavelength (micron)
#  (3) limiting point source flux density (Jy) that can be detected at SNR=10 in 10^4 s.
#  (4) Code for instrument/observatory.   0=NIRSpec, 1=NIRCam, 2=MIRI,  4=HST, 5=WISE, 6=Spitzer, 10=gemini, 11=herschel, 12=sofia,
#                                        13=alma(cycle0), 14=alma(finished), 15=VLA, 16=EVLA
#  (5) Reference for the sensitivity.  For JWST, the requirement document is given.  For other observatories, 
#      the calculation method is given.
#
#instr  wave(um) SNR10in10^4sJy  code  reference
#
# JWST high-level requirements for NIRCam:
#NIRCAM  2.0      11.4E-9         1   ISIM-153 requirement
#NIRCAM  3.5      13.8E-9         1   ISIM-153 requirement
# JWST instrument-level requirements for NIRCam:
F070W   0.70    20.9E-9          1   NRC-57, Sensitivity req in Nircam Specification
F090W   0.90    14.3E-9          1   NRC-57, Sensitivity req in Nircam Specification
F115W   1.15    11.8E-9          1   NRC-57, Sensitivity req in Nircam Specification
F150W   1.50    11.2E-9          1   NRC-57, Sensitivity req in Nircam Specification
F200W   2.00    11.4E-9          1   NRC-57, Sensitivity req in Nircam Specification
F277W   2.77    12.3E-9          1   NRC-57, Sensitivity req in Nircam Specification
F356W   3.56    13.8E-9          1   NRC-57, Sensitivity req in Nircam Specification
F444W   4.44    24.5E-9          1   NRC-57, Sensitivity req in Nircam Specification
#
# JWST MIRI
MIRI    5.6     0.2E-6            2   Appendix C of the MIRI Functional Requirements Document (JWST-RQMT-002063)
MIRI    7.7     0.28E-6           2   Appendix C of JWST-RQMT-002063
MIRI    10.0    0.7E-6            2   Appendix C of JWST-RQMT-002063
MIRI    10.0    700.0E-9          2   ISIM-153 requirement
#narrowband  MIRI    11.3    1.8E-6            2   Appendix C of JWST-RQMT-002063     # cluttered up plot, so commented out
MIRI    12.8    1.4E-6            2   Appendix C of JWST-RQMT-002063
MIRI    15.0    2.1E-6            2   Appendix C of JWST-RQMT-002063
MIRI    18.0    4.3E-6            2   Appendix C of JWST-RQMT-002063
MIRI    21.0    8.6E-6            2   Appendix C of JWST-RQMT-002063
MIRI    21.0    8.7E-6            2   ISIM-153 requirement
MIRI    25.5    29E-6             2   Appendix C of JWST-RQMT-002063
#
# JWST NIRSpec
nirspec 3.0     1.32E-7           0   ISIM-153 requirement; NSFR-10 in NIRSpec Functional Requirements Document (JWST-RQMT-002060)
#
#
# Spitzer
IRAC    3.5      0.6E-6          6   SENSPET (Spitzer exposure time calculator); near confusion limit
IRAC    4.5      1.2E-6          6   SENSPET; near confusion limit
IRAC    5.8      8E-6            6   SENSPET
IRAC    8.0      9.8E-6          6   SENSPET
MIPS    24.0     112E-6          6   Dole et al. 2004 confusion limit, scaling from SNR=5
MIPS    70.0     6E-3            6   Dole et al. 2004 confusion limit, scaling from SNR=5
MIPS    160.0    80E-3           6   Dole et al. 2004 confusion limit, scaling from SNR=5

#
# Hubble
WFC3    0.606    1.5E-8          4   Same for ACS & WFC3; Inst.Hand, Tab6.10, scaled
WFC3    0.814    3.2E-8          4   WFC3-UVIS
ACS     0.814    2.5E-8          4   ACS
WFC3    1.1      2.6E-8          4   WFC3 Inst Hand, Tab 7.10, scaled as in notes
WFC3    1.6      5.0E-8          4   WFC3 Inst Hand, Tab 7.10, scaled as in notes
#NIC3    1.60     1.95E-7         4   Nicmos Nic3, Nicmos ETC, flat in fnu spectrum, r=0.5" circular extraction 
#				        above commented out since WFC3 is superior at 1.6 um
NIC3    1.75     6.5E-7          4   Nicmos Nic3, Nicmos ETC, flat in fnu spectrum, r=0.5" circular extraction 
#
# It's not fair to put WISE limiting fluxes on this plot, since WISE is shallow and all-sky, not deep and 
# pencil-beam.  But, in case you want to compare to WISE, here are the SNR=10 limits (scaled from SNR=5
WISE    3.35     0.16E-3         5   Wright et al. 2010 ApJ
WISE    4.60     0.22E-3         5   Wright et al. 2010 ApJ
WISE    11.56    2E-3            5   Wright et al. 2010 ApJ
WISE    22.09    12E-3           5   Wright et al. 2010 ApJ

# Expected SOFIA limits:
FLITECAM 1.2   6.00E-06      12    sofia flitecam website, http://www.sofia.usra.edu/Science/instruments/instruments_flitecam.html, scaled to 10^4s, SNR=10
FLITECAM 1.7   7.50E-06      12
FLITECAM 2.2   6.75E-06      12
FLITECAM 2.4   3.75E-06      12
FLITECAM 3.2   1.35E-05      12
FLITECAM 3.8   7.50E-05      12
FLITECAM 4.7   3.75E-04      12
FORCAST  6.5   0.06          12  # scaling from http://www.sofia.usra.edu/Science/instruments/instruments_forcast.html
FORCAST  20    0.038         12
FORCAST  25    0.071         12

# GEMINI NIRI
GMOS-g'	 0.475	1.07E-07     10  from ETC
GMOS-r'	 0.630	1.60E-07     10
GMOS-i'	 0.780	2.30E-07     10
GMOS-z'	 0.950	5.30E-07     10
GMOS-Y	 1.01	2.00E-06     10
NIRI 1.25   1.1E-06  10   http://www.gemini.edu/sciops/instruments/niri/itc-sensitivity-and-overheads?q=node/10088, scaled to sn=10, 10^4s
NIRI 1.65   1.7E-06  10
NIRI 2.20   9.0E-07  10
NIRI 3.76   5.6E-05  10
NIRI 4.68   4.4E-04  10
#
#
#Extending comparison beyond the wavelength range of JWST, for general "place of JWST among great observatories" plots.
Herschel-PACS   70.  6E-3    11  # PACS_flyer_2May2010.pdf
Herschel-PACS  100.  6E-3    11  # PACS_flyer_2May2010.pdf
Herschel-PACS  160.  12E-3   11  # PACS_flyer_2May2010.pdf.  Confusion is not that important:  1.4 mJy 1 sig.
Herschel-SPIRE 250.  6E-3    11  # From Herschel-Spot.  Scaled 1sig->SNR=10.  This includes shot, instrumental noise,
				 # but dominated by confusion, and therefore limits are close to the SPIRE confusion 
                                 # limits as measured by Nguyen et al. 2010.
Herschel-SPIRE 350.  8.3E-2  11  # Ditto
Herschel-SPIRE 500.  10.3E-2 11  # Ditto
#
# ALMA in Cycle 0
band3         4.0E3  0.17E-3 13 # https://almascience.nrao.edu/call-for-proposals/capabilities, scaled 1hr->10^4s, SNR=5 to SNR=10
band6         1.7E3  0.24E-3 13
band7        1.16E3  0.44E-3 13
band9         590.   3.84E-3 13
# ALMA when finished            # http://almascience.eso.org/call-for-proposals/sensitivity-calculator, upped to 50x12m, 12x7m antennae
band3        4E3    5E-5     14
band4        2.85E3 8E-5     14 
band6        1.7E3  8E-5     14
band7        1.16E3 1.4E-4   14 
band8         1160  1.4E-4   14
band9          590  1.3E-3   14
band10         470  3.1E-3   14

#multiply tabulated sensitivites x21 to get 10^4s, SNR=10, then 1E-3 to get to Jy
VLA         400E4.   0.4    15  # http://www.vla.nrao.edu/astro/guides/vlas/current/node11.html, scaled SNR=1->SNR=10, 12 hr to 10^4s
VLA          90E4.   3.9E-3 15
VLA          20E4    1.5E-4 15
VLA          6.0E4   1.5E-4 15
VLA          3.6E4   1.2E-4 15
VLA          1.3E4   2.7E-4 15  
VLA          0.7E4   6.7E-4 15  
#
EVLA         8E3     32E-6  16 http://www.vla.nrao.edu/astro/guides/vlas/current/node11.html, scaled SNR=1->SNR=10, 9 hr to 10^4s
EVLA         1.1E4   15E-6  16 
EVLA         1.8E4   11E-6  16
EVLA         6.7E4    9E-6  16
EVLA         2.7E5   29E-6  16

# Further description of how comparison sensitivities were calculated:
#
# MIPS/Spitzer hits the 24um confusion well before 10^4 s.
# Therefore, to get a relevant 24um Spitzer performance here, I took
# the SNR=5 SDC value of 56 uJy from Dole et al.  2004, and simply
# multiplied by 2 to get SNR=10.  In detail this isn't quite right,
# but should be close.
#
# As for IRAC/Spitzer, Fazio et al. 2004 reported that 5.8, 8 micron bands weren't 
# confused even in 15,000s -- so it's safe to use SENSPET.  3.5, 4.5 micron bands 
# start having confusion after 2000s (Fazio et al. 2004), which means the SENSPET 
# values are probably a bit optimistic.  For cross-check, Krick et al 2009 reports 
# 3 sigma 95% completeness limits of 0.2, 0.17 microJy in ch1,2 for a 36ks exposure;  
# to 10 sigma that would be 0.7, 0.6 muJy.  This confirms that the SENSPET values
# are a bit optimistic.  Still, let's use them here, to be maximally fair to Spitzer.
#
# HST:  WFC3-IR Instrument Handbook, table 7.10 gives limiting-magnitudes, SNR=10,
# 1 hr and 10 hr exposure.  For both 1 and 10 hr limits, I converted from mAB 
# to Jy, and scaled to 10^4s.  The resulting scaled limits agree to 5%. 
# Repeated for WFC3-UVIS and ACS.
#
# WISE:  Wright et al 2010 ApJ, Section 3, has SNR=5, w/ confusion.
# D. Benford (priv. comm.) warns that these values are skewed high by the Galactic plane; 
# WISE does better in the galactic poles.  
#
# For GEMINI GMOS, I used the ETC, 10^4s, SNR=10, spectrum flat in fnu, and the passbands above, and 
# iterated to find the limiting flux density.  For GEMINI NIRI, I used the quoted sensitivities at
# http://www.gemini.edu/sciops/instruments/niri/itc-sensitivity-and-overheads?q=node/10088, 
# and scaled to SNR=10, 10^4s.

# Data tabulated by Jane Rigby.  Please email Jane.R.Rigby@nasa.gov if you have comments or suggestions.