Photometric system

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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.

Contents

A commonly adopted standardized photometric system is the Johnson-Morgan or UBV photometric system (1953). At present, there are more than 200 photometric systems.[ citation needed ]

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

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). [lower-alpha 1] 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. [lower-alpha 2]

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.

Filter
Letter
Effective Wavelength Midpoint
λeff for Standard Filter [2]
Full width at half maximum [2]
[lower-alpha 3] (archetypal Bandwidth) (Δλ) [lower-alpha 4]
Variant(s)Description
Ultraviolet
U365 nm66 nmu, u', u*"U" stands for ultraviolet.
Visible
B445 nm94 nmb"B" stands for blue.
G [3] 464 nm128 nmg, g'"G" stands for green.
V551 nm88 nmv, v'"V" stands for visual.
R658 nm138 nmr, r', R', Rc, Re, Rj"R" stands for red.
Near-Infrared
I806 nm149 nmi, i', Ic, Ie, Ij"I" stands for infrared.
z-s'893.2 nm100 nmz-s'
Z900 nm [4] 152 nmz, z'
Y1020 nm120 nmy
J 1220 nm213 nmJ', Js
H 1630 nm307 nm
K 2190 nm390 nmK Continuum, K', Ks, Klong, K8, nbK
L 3450 nm472 nmL', nbL'
Mid-Infrared
M 4750 nm460 nmM', nbM
N 10500 nm2500 nm
Q21000 nm [5] 5800 nm [5] Q'

Note: colors are only approximate and based on wavelength to sRGB representation (when possible). [6]

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. [7]

Filters used

The filters currently being used by other telescopes or organizations.

Units of measurements:

NameFiltersLink
2.2 m telescope at La Silla, ESOJ = 1.24 μmH = 1.63 μmK = 2.19 μmL' = 3.78 μmM = 4.66 μmN1 = 8.36 μmN2 = 9.67 μmN3 = 12.89 μm 2.2 m telescope at La Silla, ESO [8]
2MASS/PAIRITELJ = 1.25 μmH = 1.65 μmKs = 2.15 μm Two Micron All-Sky Survey, Peters Automated InfraRed Imaging TELescope
CFHTLS (Megacam)u* = 374 nmg' = 487 nmr' = 625 nmi' = 770 nmz' = 890 nm Canada-France-Hawaii Telescope
Chandra X-ray ObservatoryLETG = 0.08-0.2 keVHETG = 0.4-10 keV Chandra X-ray Observatory
CTIOJ = 1.20 μmH = 1.60 μmK = 2.20 μmL = 3.50 μm Cerro Tololo Inter-American Observatory, a division of NOAO
Cousins RI photometryRc = 647 nmIc = 786.5 nmCousins RI photometry, 1976 [9]
the Dark Energy Camerag = 472.0 nmr = 641.5 nmi = 783.5 nmz = 926.0 nmY = 1009.5 nmCentral wavelengths for bands in the Dark Energy Survey [10]
DENISI = 0.79 μmJ = 1.24 μmK = 2.16 μm Deep Near Infrared Survey
Eggen RI photometryRe = 635 nmIe = 790 nmEggen RI photometry, 1965 [11]
FISN60 = 65.00 μmWIDE-S = 90.00 μmWIDE-L = 145.00 μmN160 = 160.00 μmFar-Infrared Surveyor on board, AKARI space telescope
GaiaG = 673 nmGBP = 532 nmGRP = 797 nmGRVS = 860 nm Gaia (spacecraft) [12]
GALEX [13] NUV = 175–280 nmFUV = 135–175 nm GALaxy Evolution Explorer
GOODS (Hubble ACS)B = 435 nmV = 606 nmi = 775 nmz = 850 nm Advanced Camera for Surveys on the Hubble Space Telescope
HAWC+Band 1 = 53 μmBand 2 = 89 μmBand 3 = 154 μmBand 4 = 214 μmHigh-resolution Airborne Wideband Camera+ for SOFIA [14]
HDF450 nm606 nm814 nm Hubble Deep Field from the Hubble Space Telescope
IRTF NSFCAMJ = 1.26 μmH = 1.62 μmK' = 2.12 μmKs = 2.15 μmK = 2.21 μmL = 3.50 μmL' = 3.78 μmM' = 4.78 μmM = 4.85 μm NASA Infrared Telescope Facility NSFCAM [15]
ISAAC UTI/VLT [16] Js = 1.2 μmH = 1.6 μmKs = 2.2 μmL = 3.78 μm Brα = 4.07 μm Infrared Spectrometer And Array Camera at Very Large Telescope
Johnson system (UBV)U = 364 nmB = 442 nmV = 540 nm UBV photometric system
Vera C. Rubin Observatory (LSST) [17] u = 320.5–393.5 nmg = 401.5–551.9 nmr = 552.0–691.0 nmi = 691.0–818.0 nmz = 818.0–923.5 nmy = 923.8–1084.5 nm Vera C. Rubin Observatory
OMCJohnson V-filter = 500-580 nmOptical Monitor Camera [18] on INTEGRAL
Pan-STARRSg = 481 nmr = 617 nmi = 752 nmz = 866 nmy = 962 nm Panoramic Survey Telescope And Rapid Response System [19]
ProNaOS/SPMBand 1 = 180-240 μmBand 2 = 240-340 μmBand 3 = 340-540 μmBand 4 = 540-1200 μmPROgramme NAtional d'Observations Submillerètrique/Systéme Photométrique Multibande, balloon-borne experiment [20]
Sloan, SDSSu' = 354 nmg' = 475 nmr' = 622 nmi' = 763 nmz' = 905 nm Sloan Digital Sky Survey
SPIRIT IIIBand B1 = 4.29 μmBand B2 = 4.35 μmBand A = 8.28 μmBand C = 12.13 μmBand D = 14.65 μmBand E = 21.34 μmInfrared camera on Midcourse Space Experiment [21]
Spitzer IRACch1 = 3.6 μmch2 = 4.5 μmch3 = 5.8 μmch4 = 8.0 μmInfrared Array Camera on Spitzer Space Telescope
Spitzer MIPS24 μm70 μm160 μmMultiband Imaging Photometer for Spitzer on Spitzer
Stromvil filtersU = 345 nmP = 374 nmS = 405 nmY = 466 nmZ = 516 nmV = 544 nmS = 656 nmStromvil photometry
Strömgren filtersu = 350 nmv = 411 nmb = 467 nmy = 547 nmβ narrow = 485.8 nmβ wide = 485 nm Strömgren photometric system
UKIDSS (WFCAM)Z = 882 nmY = 1031 nmJ = 1248 nmH = 1631 nmK = 2201 nm UKIRT Infrared Deep Sky Survey
Vilnius photometric systemU = 345 nmP = 374 nmS = 405 nmY = 466 nmZ = 516 nmV = 544 nmS = 656 nm Vilnius photometric system
VISTA IRCZ = 0.88 μmY = 1.02 μmJ = 1.25 μmH = 1.65 μmKs = 2.20 μmNB1.18 = 1.18 μm Visible & Infrared Survey Telescope for Astronomy
WISEW1 = 3.4 μmW2 = 4.6 μmW3 = 12 μmW4 = 22 μm Wide-field Infrared Survey Explorer
XMM-Newton OMUVW2 = 212 nmUVM2 = 231 nmUVW1 = 291 nmU = 344 nmB = 450 nmV = 543 nm XMM-Newton Optical/UV Monitor [22]
XEST SurveyUVW2 = 212 nmUVM2 = 231 nmUVW1 = 291 nmU = 344 nmB = 450 nmV = 543 nmJ = 1.25 μmH = 1.65 μmKs = 2.15 μmSurvey includes the point source of 2MASS with XMM-Newton OM [23]

Note: colors are only approximate and based on wavelength to sRGB representation (when possible). [24]

See also

References and footnotes

  1. Spectral Colors
  2. 1 2 Binney, J.; Merrifield M. Galactic Astronomy, Princeton University Press, 1998, ch. 2.3.2, pp. 53
  3. Bessell, Michael S. (September 2005). "Standard Photometric Systems" (PDF). Annual Review of Astronomy and Astrophysics. 43 (1): 293–336. Bibcode:2005ARA&A..43..293B. doi:10.1146/annurev.astro.41.082801.100251. ISSN   0066-4146.
  4. Gouda, N.; Yano, T.; Kobayashi, Y.; Yamada, Y.; et al. (23 May 2005). "JASMINE: Japan Astrometry Satellite Mission for INfrared Exploration". Proceedings of the International Astronomical Union. 2004 (IAUC196): 455–468. Bibcode:2005tvnv.conf..455G. doi: 10.1017/S1743921305001614 . S2CID   123261288. z-band: 0.9 μm
  5. 1 2 Handbook of Geophysics and the Space Environment 1985, Air Force Geophysics Laboratory, 1985, ed. Adolph S. Jursa, Ch. 25, Table 25-1
  6. "Light wavelength to RGB Converter". www.johndcook.com. Retrieved 2023-07-28.
  7. Monson, Andrew J.; Pierce, Michael J. (2011). "Near-Infrared (Jhk) Photometry of 131 Northern Galactic Classical Cepheids". The Astrophysical Journal Supplement Series. 193 (1): 12. Bibcode:2011ApJS..193...12M. doi: 10.1088/0067-0049/193/1/12 . Example of use of J for "near-infrared"
  8. 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
  9. ADPS
  10. DES
  11. ADPS
  12. Jordi, C.; Gebran, M.; Carrasco, J. M.; de Bruijne, J.; Voss, H.; Fabricius, C.; Knude, J.; Vallenari, A.; Kohley, R.; Mora, A. (2010). "Gaia broad band photometry". Astronomy and Astrophysics. 523: A48. arXiv: 1008.0815 . Bibcode:2010A&A...523A..48J. doi:10.1051/0004-6361/201015441. S2CID   34033669.
  13. "GALEX Instrument Summary". Goddard Space Flight Center. Retrieved 5 June 2019.
  14. "HAWC". Archived from the original on 2008-03-13. Retrieved 2008-05-25.
  15. NSFCAM
  16. "ISAAC Overview". Paranal Instrumentation. ESO. Retrieved 13 October 2011.
  17. 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.
  18. About INTEGRAL
  19. Tonry, J. L.; Stubbs, C. W.; Lykke, K. R.; Doherty, P.; Shivvers, I. S.; Burgett, W. S.; Chambers, K. C.; Hodapp, K. W.; Kaiser, N.; Kudritzki, R.-P.; Magnier, E. A.; Morgan, J. S.; Price, P. A.; Wainscoat, R. J. (2012). "THE Pan-STARRS1 PHOTOMETRIC SYSTEM". The Astrophysical Journal. 750 (2): 99. arXiv: 1203.0297 . Bibcode:2012ApJ...750...99T. doi:10.1088/0004-637X/750/2/99. S2CID   119266289.
  20. Pajot, F.; Stepnik, B.; Lamarre, J.-M.; Bernard, J.-P.; Dupac, X.; Giard, M.; Lagache, G.; Leriche, B.; Meny, C.; Recouvreur, G.; Renault, J.-C.; Rioux, C.; Ristorcelli, I.; Serra, G.; Torre, J.-P. (2006). "Calibration of the PRONAOS/SPM submillimeter photometer" (PDF). Astronomy & Astrophysics. 447 (2): 769–781. Bibcode:2006A&A...447..769P. doi:10.1051/0004-6361:20034226. S2CID   4822401.
  21. MSXPSC – Midcourse Space Experiment (MSX) Point Source Catalog, V2.3
  22. XMM-Newton User's Handbook Sect. 3.5.3.1
  23. Audard, M.; Briggs, K. R.; Grosso, N.; Güdel, M.; Scelsi, L.; Bouvier, J.; Telleschi, A. (2007). "The XMM-Newton Optical Monitor survey of the Taurus molecular cloud". Astronomy & Astrophysics. 468 (2): 379–390. arXiv: astro-ph/0611367 . Bibcode:2007A&A...468..379A. doi:10.1051/0004-6361:20066320. S2CID   59479808.
  24. "Light wavelength to RGB Converter". www.johndcook.com. Retrieved 2023-07-28.
  1. Indigo and cyan are not standard colors. [1] Orange, yellow, and green fall under visual bands, while violet and purple are in every blue band.
  2. See Description column of the chart
  3. 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
  4. Delta lambda

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