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photometric system

{{short description|Set of well-defined passbands (or filters), with a known sensitivity to incident radiation}}

{{Other uses|Photometry (disambiguation)}}

In astronomy, a photometric system is a set of well-defined passbands (or optical filters), with a known sensitivity to incident radiation. The sensitivity usually depends on the optical system, detectors and filters used. For each photometric system a set of primary standard stars is provided.

A commonly adopted standardized photometric system is the Johnson-Morgan or UBV photometric system (1953). At present, there are more than 200 photometric systems.{{Cite journal |last1=Bessell |first1=M. S. |year=2005 |title=STANDARD PHOTOMETRIC SYSTEMS |url=https://sites.astro.caltech.edu/~george/ay122/Bessel2005ARAA43p293.pdf |journal=Annual Review of Astronomy and Astrophysics |volume=43 |pages=293–336 |doi= 10.1146/annurev.astro.41.082801.100251}}

Photometric systems are usually characterized according to the widths of their passbands:

  • broadband (passbands wider than 30 nm, of which the most widely used is Johnson-Morgan UBV system)
  • intermediate band (passbands between 10 and 30 nm wide)
  • narrow band (passbands less than 10 nm wide)

Photometric letters

Each letter designates a section of light of the electromagnetic spectrum; these cover well the consecutive major groups, near-ultraviolet (NUV), visible light (centered on the V band), near-infrared (NIR) and part of mid-infrared (MIR).{{efn|Indigo and cyan are not standard colors.[http://hyperphysics.phy-astr.gsu.edu/Hbase/vision/specol.html Spectral Colors] Orange, yellow, and green fall under visual bands, while violet and purple are in every blue band.}} The letters are not standards, but are recognized by common agreement among astronomers and astrophysicists.

The use of U,B,V,R,I bands dates from the 1950s, being single-letter abbreviations.{{efn|See Description column of the chart}}

With the advent of infrared detectors in the next decade, the J to N bands were labelled following on from near-infrared's closest-to-red band, I.

Later the H band was inserted, then Z in the 1990s and finally Y, without changing earlier definitions. Hence, H is out of alphabetical order from its neighbours, while Z,Y are reversed from the alphabetical – higher-wavelength – sub-series which dominates current photometric bands.

class="wikitable" style="text-align:center;border-collapse:collapse;" cellpadding="2"

! Filter
Letter

! Effective Wavelength Midpoint
λeff for Standard FilterBinney, J.; Merrifield M. Galactic Astronomy, Princeton University Press, 1998, ch. 2.3.2, pp. 53

! Full width at half maximum
{{efn|The width of the band of the curve's 50% upper values (that is, peak) for a natural curve of paradigm source of this light}} (archetypal Bandwidth) (Δλ){{efn|Delta lambda}}

! Variant(s)

! Description

colspan="5" {{rh}} class="table-rh" | Ultraviolet
U

| 365 nm

| 66 nm

| u, u', u*

| "U" stands for ultraviolet.

colspan="5" {{rh}} class="table-rh" | Visible
B

| 445 nm

| 94 nm

| b

| bgcolor="#0028ff" align="center" style="color:#ffffff;" |"B" stands for blue.

G{{cite journal|last1=Bessell|first1=Michael S.|title=Standard Photometric Systems|journal=Annual Review of Astronomy and Astrophysics|volume=43|issue=1|date=September 2005|pages=293–336|issn=0066-4146|doi=10.1146/annurev.astro.41.082801.100251|bibcode=2005ARA&A..43..293B|url=http://www.mso.anu.edu.au/~bessell/araapaper.pdf}}

| 464 nm

| 128 nm

| g, g'

| bgcolor="#32a852" align="center" style="color:#ffffff;" | "G" stands for green.

V

| 551 nm

| 88 nm

| v, v'

| bgcolor="#f0e13c" align="center" style="color:#000000;" | "V" stands for visual.

R

| 658 nm

| 138 nm

| r, r', R', Rc, Re, Rj

| bgcolor="#ff0000" align="center" style="color:#ffffff;" | "R" stands for red.

colspan="5" {{rh}} class="table-rh" | Near-Infrared
I

| 806 nm

| 149 nm

| i, i', Ic, Ie, Ij

| "I" stands for infrared.

z-s'

|893.2 nm

|100 nm

|z-s'

Z

| 900 nm{{cite journal|last1=Gouda |first1=N. |display-authors=4 |first2=T. |last2=Yano |first3=Y. |last3=Kobayashi |first4=Y. |last4=Yamada |first5=T. |last5=Tsujimoto |first6=T. |last6=Nakajima |first7=M. |last7=Suganuma |first8=H. |last8=Matsuhara |first9=S. |last9=Ueda |author10=the JASMINE Working Group |name-list-style=amp |date=23 May 2005 |title=JASMINE: Japan Astrometry Satellite Mission for INfrared Exploration |journal=Proceedings of the International Astronomical Union |volume=2004 |issue=IAUC196 |pages=455–468 |doi=10.1017/S1743921305001614 |bibcode=2005tvnv.conf..455G |s2cid=123261288 |quote=z-band: 0.9 μm|doi-access=free }}

|152 nm

| z, z'

|

Y

|1020 nm

|120 nm

| y

|

J

| 1220 nm

| 213 nm

| J', Js

|

H

| 1630 nm

| 307 nm

|

|

K

| 2190 nm

| 390 nm

| K Continuum, K', Ks, Klong, K8, nbK

|

L

| 3450 nm

| 472 nm

| L', nbL'

|

colspan="5" {{rh}} class="table-rh" | Mid-Infrared
M

| 4750 nm

| 460 nm

| M', nbM

|

N

| 10500 nm

| 2500 nm

|

|

Q

| 21000 nm[http://www.cnofs.org/Handbook_of_Geophysics_1985/] Handbook of Geophysics and the Space Environment 1985, Air Force Geophysics Laboratory, 1985, ed. Adolph S. Jursa, Ch. 25, Table 25-1

| 5800 nm

| Q'

|

Note: colors are only approximate and based on wavelength to sRGB representation (when possible).{{Cite web |title=Light wavelength to RGB Converter |url=https://www.johndcook.com/wavelength_to_RGB.html |access-date=2023-07-28 |website=www.johndcook.com}}

Combinations of these letters are frequently used; for example the combination JHK has been used more or less as a synonym of "near-infrared", and appears in the title of many papers.{{cite journal|doi=10.1088/0067-0049/193/1/12|title=Near-Infrared (Jhk) Photometry of 131 Northern Galactic Classical Cepheids|journal=The Astrophysical Journal Supplement Series|volume=193|pages=12|year=2011|last1=Monson|first1=Andrew J.|last2=Pierce|first2=Michael J.|issue=1 |bibcode=2011ApJS..193...12M|doi-access=free}} Example of use of J for "near-infrared"

Filters used

The filters currently being used by other telescopes or organizations.

Units of measurements:

class="wikitable" style="text-align:center;border-collapse:collapse;" cellpadding="2"

!Name

! colspan="9" |Filters

!Link

2.2 m telescope at La Silla, ESO

|J = 1.24 μm

|H = 1.63 μm

|K = 2.19 μm

|L' = 3.78 μm

|M = 4.66 μm

|N1 = 8.36 μm

|N2 = 9.67 μm

|N3 = 12.89 μm

| colspan="1" |

|2.2 m telescope at La Silla, ESO[http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?1990MNRAS.247..624A&db_key=AST&nosetcookie=1 A study of the Chamaeleon I dark cloud and T-association. II – High-resolution IRAS maps around HD 97048 and 97300], Assendorp, R.; Wesselius, P. R.; Prusti, T.; Whittet, D. C. B., 1990

2MASS/PAIRITEL

|J = 1.25 μm

|H = 1.65 μm

|Ks = 2.15 μm

| colspan="6" |

|Two Micron All-Sky Survey, Peters Automated InfraRed Imaging TELescope

CFHTLS (Megacam)

|u* = 374 nm

| align="center" bgcolor="#00f3ff" style="color:#000;" |g' = 487 nm

| align="center" bgcolor="#ff6300" style="color:#ffffff;" |r' = 625 nm

| align="center" bgcolor="#770000" style="color:#ffffff;" |i' = 770 nm

|z' = 890 nm

| colspan="4" |

|Canada-France-Hawaii Telescope

Chandra X-ray Observatory

|LETG = 0.08-0.2 keV

|HETG = 0.4-10 keV

| colspan="7" |

|Chandra X-ray Observatory

CTIO

|J = 1.20 μm

|H = 1.60 μm

|K = 2.20 μm

|L = 3.50 μm

| colspan="5" |

|Cerro Tololo Inter-American Observatory, a division of NOAO

Cousins RI photometry

| align="center" bgcolor="#ff0000" style="color:#ffffff;" |Rc = 647 nm

|Ic = 786.5 nm

| colspan="7" |

|Cousins RI photometry, 1976[http://ulisse.pd.astro.it/Astro/ADPS/Systems/Sys_093/index_093.html ADPS]

the Dark Energy Camera

| align="center" bgcolor="#00b2ff" style="color:#ffffff;" |g = 472.0 nm

| align="center" bgcolor="#ff1600" style="color:#ffffff;" |r = 641.5 nm

|i = 783.5 nm

|z = 926.0 nm

|Y = 1009.5 nm

| colspan="4" |

|Central wavelengths for bands in the Dark Energy Survey[http://data.darkenergysurvey.org/aux/releasenotes/DESDMrelease.html DES]

DENIS

|I = 0.79 μm

|J = 1.24 μm

|K = 2.16 μm

| colspan="6" |

|Deep Near Infrared Survey

Eggen RI photometry

| align="center" bgcolor="#ff3900" style="color:#ffffff;"|Re = 635 nm

|Ie = 790 nm

| colspan="7" |

|Eggen RI photometry, 1965[http://ulisse.pd.astro.it/Astro/ADPS/Systems/Sys_032/index_032.html ADPS]

FIS

|N60 = 65.00 μm

|WIDE-S = 90.00 μm

|WIDE-L = 145.00 μm

|N160 = 160.00 μm

| colspan="5" |

|Far-Infrared Surveyor on board, AKARI space telescope

Gaia

| align="center" bgcolor="#ff0000" style="color:#ffffff;"|G = 673 nm

| align="center" bgcolor="#65ff00" style="color:#000;"|GBP = 532 nm

|GRP = 797 nm

|GRVS = 860 nm

| colspan="5" |

|Gaia (spacecraft){{cite journal |author1=Jordi, C. |author2=Gebran, M. |author3=Carrasco, J. M. |author4=de Bruijne, J. |author5=Voss, H. |author6=Fabricius, C. |author7=Knude, J. |author8=Vallenari, A. |author9=Kohley, R. |author10=Mora, A. |year=2010 |title=Gaia broad band photometry |journal=Astronomy and Astrophysics |volume=523 |pages=A48 |arxiv=1008.0815 |bibcode=2010A&A...523A..48J |doi=10.1051/0004-6361/201015441 |s2cid=34033669}}

GALEX{{cite web |title=GALEX Instrument Summary |url=https://asd.gsfc.nasa.gov/archive/galex/Documents/instrument_summary.html |access-date=5 June 2019 |publisher=Goddard Space Flight Center}}

|NUV = 175–280 nm

|FUV = 135–175 nm

| colspan="7" |

|GALaxy Evolution Explorer

GOODS (Hubble ACS)

| align="center" bgcolor="#2300ff" style="color:#ffffff;"|B = 435 nm

| align="center" bgcolor="#ffa900" style="color:#ffffff;"|V = 606 nm

| align="center" bgcolor="#6d0000" style="color:#ffffff;"|i = 775 nm

|z = 850 nm

| colspan="5" |

|Advanced Camera for Surveys on the Hubble Space Telescope

HAWC+

|Band 1 = 53 μm

|Band 2 = 89 μm

|Band 3 = 154 μm

|Band 4 = 214 μm

| colspan="5" |

|High-resolution Airborne Wideband Camera+ for SOFIA{{Cite web |title=HAWC |url=http://astro.uchicago.edu/hawc/ |url-status=dead |archive-url=https://web.archive.org/web/20080313073717/http://astro.uchicago.edu/hawc/ |archive-date=2008-03-13 |access-date=2008-05-25}}

HDF

| align="center" bgcolor="#0046ff" style="color:#ffffff;"|450 nm

| align="center" bgcolor="#ffa900" style="color:#ffffff;"|606 nm

|814 nm

| colspan="6" |

|Hubble Deep Field from the Hubble Space Telescope

IRTF NSFCAM

|J = 1.26 μm

|H = 1.62 μm

|K' = 2.12 μm

|Ks = 2.15 μm

|K = 2.21 μm

|L = 3.50 μm

|L' = 3.78 μm

|M' = 4.78 μm

|M = 4.85 μm

|NASA Infrared Telescope Facility NSFCAM[http://irtfweb.ifa.hawaii.edu/~nsfcam2/Welcome.html NSFCAM]

ISAAC UTI/VLT{{cite web |title=ISAAC Overview |url=http://www.eso.org/sci/facilities/paranal/instruments/isaac/overview.html |access-date=13 October 2011 |work=Paranal Instrumentation |publisher=ESO}}

|Js = 1.2 μm

|H = 1.6 μm

|Ks = 2.2 μm

|L = 3.78 μm

|Brα = 4.07 μm

| colspan="4" |

|Infrared Spectrometer And Array Camera at Very Large Telescope

Johnson system (UBV)

|U = 364 nm

| align="center" bgcolor="#0013ff" style="color:#ffffff;"|B = 442 nm

| align="center" bgcolor="#81ff00" style="color:#000;"|V = 540 nm

| colspan="6" |

|UBV photometric system

Vera C. Rubin Observatory (LSST)LSST filter characteristics taken from https://github.com/lsst/throughputs/blob/master/baseline/ (see the filter_X.dat files) with the limits at half the peak transmission.

|u = 320.5–393.5 nm

| align="center" bgcolor="#00c8ff" style="color:#ffffff;" |g = 401.5–551.9 nm

| align="center" bgcolor="#ff6f00" style="color:#ffffff;" |r = 552.0–691.0 nm

| align="center" bgcolor="#970000" style="color:#ffffff;" |i = 691.0–818.0 nm

|z = 818.0–923.5 nm

|y = 923.8–1084.5 nm

| colspan="3" |

|Vera C. Rubin Observatory

OMC

| align="center" bgcolor="#81ff00" style="color:#000;" |Johnson V-filter = 500-580 nm

| colspan="8" |

|Optical Monitor Camera[http://heasarc.gsfc.nasa.gov/docs/integral/inthp_about.html About INTEGRAL] on INTEGRAL

Pan-STARRS

| align="center" bgcolor="#00daff" style="color:#ffffff;"|g = 481 nm

| align="center" bgcolor="#ff8200" style="color:#ffffff;"|r = 617 nm

| align="center" bgcolor="#9d0000" style="color:#ffffff;"|i = 752 nm

|z = 866 nm

|y = 962 nm

| colspan="4" |

|Panoramic Survey Telescope And Rapid Response System{{cite journal |last1=Tonry |first1=J. L. |last2=Stubbs |first2=C. W. |last3=Lykke |first3=K. R. |last4=Doherty |first4=P. |last5=Shivvers |first5=I. S. |last6=Burgett |first6=W. S. |last7=Chambers |first7=K. C. |last8=Hodapp |first8=K. W. |last9=Kaiser |first9=N. |last10=Kudritzki |first10=R.-P. |last11=Magnier |first11=E. A. |last12=Morgan |first12=J. S. |last13=Price |first13=P. A. |last14=Wainscoat |first14=R. J. |year=2012 |title=THE Pan-STARRS1 PHOTOMETRIC SYSTEM |journal=The Astrophysical Journal |volume=750 |issue=2 |page=99 |arxiv=1203.0297 |bibcode=2012ApJ...750...99T |doi=10.1088/0004-637X/750/2/99 |s2cid=119266289}}

ProNaOS/SPM

|Band 1 = 180-240 μm

|Band 2 = 240-340 μm

|Band 3 = 340-540 μm

|Band 4 = 540-1200 μm

| colspan="5" |

|PROgramme NAtional d'Observations Submillerètrique/Systéme Photométrique Multibande, balloon-borne experiment{{Cite journal |last1=Pajot |first1=F. |last2=Stepnik |first2=B. |last3=Lamarre |first3=J.-M. |last4=Bernard |first4=J.-P. |last5=Dupac |first5=X. |last6=Giard |first6=M. |last7=Lagache |first7=G. |last8=Leriche |first8=B. |last9=Meny |first9=C. |last10=Recouvreur |first10=G. |last11=Renault |first11=J.-C. |last12=Rioux |first12=C. |last13=Ristorcelli |first13=I. |last14=Serra |first14=G. |last15=Torre |first15=J.-P. |year=2006 |title=Calibration of the PRONAOS/SPM submillimeter photometer |url=http://www.aanda.org/articles/aa/pdf/2006/08/aa0226-03.pdf |journal=Astronomy & Astrophysics |volume=447 |issue=2 |pages=769–781 |bibcode=2006A&A...447..769P |doi=10.1051/0004-6361:20034226 |s2cid=4822401}}

Sloan, SDSS

|u' = 354 nm

| align="center" bgcolor="#00c0ff" style="color:#ffffff;"|g' = 475 nm

| align="center" bgcolor="#ff6f00" style="color:#ffffff;"|r' = 622 nm

| align="center" bgcolor="#860000" style="color:#ffffff;"|i' = 763 nm

|z' = 905 nm

| colspan="4" |

|Sloan Digital Sky Survey

SPIRIT III

|Band B1 = 4.29 μm

|Band B2 = 4.35 μm

|Band A = 8.28 μm

|Band C = 12.13 μm

|Band D = 14.65 μm

|Band E = 21.34 μm

| colspan="3" |

|Infrared camera on Midcourse Space Experiment[https://web.archive.org/web/20061001002157/http://heasarc.nasa.gov/W3Browse/all/msxpsc.html MSXPSC – Midcourse Space Experiment (MSX) Point Source Catalog, V2.3]

Spitzer IRAC

|ch1 = 3.6 μm

|ch2 = 4.5 μm

|ch3 = 5.8 μm

|ch4 = 8.0 μm

| colspan="5" |

|Infrared Array Camera on Spitzer Space Telescope

Spitzer MIPS

|24 μm

|70 μm

|160 μm

| colspan="6" |

|Multiband Imaging Photometer for Spitzer on Spitzer

Stromvil filters

|U = 345 nm

|P = 374 nm

| align="center" bgcolor="#8200c8" style="color:#ffffff;"|S = 405 nm

| align="center" bgcolor="#0097ff" style="color:#ffffff;"|Y = 466 nm

| align="center" bgcolor="#24ff00" style="color:#000;"|Z = 516 nm

| align="center" bgcolor="#8fff00" style="color:#000;"|V = 544 nm

| align="center" bgcolor="#ff0000" style="color:#ffffff;"|S = 656 nm

| colspan="2" |

|Stromvil photometry

Strömgren filters

|u = 350 nm

| align="center" bgcolor="#7c00de" style="color:#ffffff;"|v = 411 nm

| align="center" bgcolor="#009cff" style="color:#ffffff;" |b = 467 nm

| align="center" bgcolor="#99ff00"|y = 547 nm

| align="center" bgcolor="#00efff" |β narrow = 485.8 nm

| align="center" bgcolor="#00eaff"|β wide = 485 nm

| colspan="3" |

|Strömgren photometric system

UKIDSS (WFCAM)

|Z = 882 nm

|Y = 1031 nm

|J = 1248 nm

|H = 1631 nm

|K = 2201 nm

| colspan="4" |

|UKIRT Infrared Deep Sky Survey

Vilnius photometric system

|U = 345 nm

|P = 374 nm

| align="center" bgcolor="#8200c8" style="color:#ffffff;"|S = 405 nm

| align="center" bgcolor="#0097ff" style="color:#ffffff;"|Y = 466 nm

| align="center" bgcolor="#24ff00" style="color:#000;"|Z = 516 nm

| align="center" bgcolor="#8fff00" style="color:#000;"|V = 544 nm

| align="center" bgcolor="#ff0000" style="color:#ffffff;"|S = 656 nm

| colspan="2" |

|Vilnius photometric system

VISTA IRC

|Z = 0.88 μm

|Y = 1.02 μm

|J = 1.25 μm

|H = 1.65 μm

|Ks = 2.20 μm

|NB1.18 = 1.18 μm

| colspan="3" |

|Visible & Infrared Survey Telescope for Astronomy

WISE

|W1 = 3.4 μm

|W2 = 4.6 μm

|W3 = 12 μm

|W4 = 22 μm

| colspan="5" |

|Wide-field Infrared Survey Explorer

XMM-Newton OM

|UVW2 = 212 nm

|UVM2 = 231 nm

|UVW1 = 291 nm

|U = 344 nm

| align="center" bgcolor="#0046ff" style="color:#ffffff;"|B = 450 nm

| align="center" bgcolor="#8cff00" style="color:#000;"|V = 543 nm

| colspan="3" |

|XMM-Newton Optical/UV Monitor[https://xmm-tools.cosmos.esa.int/external/xmm_user_support/documentation/uhb/omfilters.html XMM-Newton User's Handbook Sect. 3.5.3.1]

XEST Survey

|UVW2 = 212 nm

|UVM2 = 231 nm

|UVW1 = 291 nm

|U = 344 nm

| align="center" bgcolor="#0046ff" style="color:#ffffff;"|B = 450 nm

| align="center" bgcolor="#8cff00" style="color:#000;"|V = 543 nm

|J = 1.25 μm

|H = 1.65 μm

|Ks = 2.15 μm

|Survey includes the point source of 2MASS with XMM-Newton OM{{cite journal |last1=Audard |first1=M. |last2=Briggs |first2=K. R. |last3=Grosso |first3=N. |last4=Güdel |first4=M. |last5=Scelsi |first5=L. |last6=Bouvier |first6=J. |last7=Telleschi |first7=A. |year=2007 |title=The XMM-Newton Optical Monitor survey of the Taurus molecular cloud |journal=Astronomy & Astrophysics |volume=468 |issue=2 |pages=379–390 |arxiv=astro-ph/0611367 |bibcode=2007A&A...468..379A |doi=10.1051/0004-6361:20066320 |s2cid=59479808}}

Note: colors are only approximate and based on wavelength to sRGB representation (when possible).{{Cite web |title=Light wavelength to RGB Converter |url=https://www.johndcook.com/wavelength_to_RGB.html |access-date=2023-07-28 |website=www.johndcook.com}}

See also

References and footnotes

{{Reflist}}

{{notelist}}

External links

  • Johnson, H. L.; Morgan, W. W. (1953), Fundamental stellar photometry for standards of spectral type on the revised system of the Yerkes spectral atlas, The Astrophysical Journal, vol. 117, pp. 313–352 [http://adsabs.harvard.edu/abs/1953ApJ...117..313J]
  • [http://ulisse.pd.astro.it/Astro/ADPS/Systems/index.html The Asiago Database on Photometric Systems]
  • Michael S. Bessell (2005), STANDARD PHOTOMETRIC SYSTEMS, Annual Review of Astronomy and Astrophysics vol. 43, pp. 293–336
  • [http://adsabs.harvard.edu/abs/2005A&A...434..987A Infrared portrait of the nearby massive star-forming region IRAS 09002-4732], Apai, D.; Linz, H.; Henning, Th.; Stecklum, B., 2005

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