Photometric system
In astronomy, a photometric system is a set of well-defined passbands (or 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.
The first known standardized photometric system is the Johnson-Morgan or UBV photometric system (1953). At present, there are more than 200 photometric systems.
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 particular section of the electromagnetic spectrum; most of these sections fall within the region spanning the near-ultraviolet (NUV), the visible and the majority of the near-infrared (NIR).
Indigo and cyan are not standard colors.[1] Orange, yellow, and green fall under visual bands, while violet and purple are under the blue bands. The letters are not standards, but are recognized by common agreement among astronomers and astrophysicists.
Filter Letter | Effective Wavelength Midpoint λeff For Standard Filter[2] | Full Width Half Maximum[2] (Bandwidth Δλ) | Variant(s) | Description |
---|---|---|---|---|
Ultraviolet | ||||
U | 365 nm | 66 nm | u, u', u* | "U" stands for ultraviolet. |
Visible | ||||
B | 445 nm | 94 nm | b | "B" stands for blue. |
V | 551 nm | 88 nm | v, v' | "V" stands for visual. |
G | g, g' | "G" stands for green (visual). | ||
R | 658 nm | 138 nm | r, r', R', Rc, Re, Rj | "R" stands for red. |
Near-Infrared | ||||
I | 806 nm | 149 nm | i, i', Ic, Ie, Ij | "I" stands for infrared. |
Z | 900 nm[3] | 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' | |
Mid-Infrared | ||||
M | 4750 nm | 460 nm | M', nbM | |
N | 10500 nm | 2500 nm | ||
Q | 21000 nm[4] | 5800 nm[4] | Q' | |
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.[5]
Filters used
The filters currently being used by other telescopes or organizations.
Units of measurements:
- Å = Ångström
- nm = nanometre
- μm = micrometre
Name | 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 | 2.2 m telescope at La Silla, ESO[6] | |
2MASS/PAIRITEL | J = 1.25 μm | H = 1.65 μm | Ks = 2.15 μm | Two Micron All-Sky Survey, Peters Automated InfraRed Imaging TELescope | ||||||
CFHTLS (Megacam) | u* = 374 nm | g' = 487 nm | r' = 625 nm | i' = 770 nm | z' = 890 nm | Canada-France-Hawaii Telescope | ||||
Chandra X-ray Observatory | LETG = 0.08-0.2 keV | HETG = 0.4-10 keV | Chandra X-ray Observatory | |||||||
CTIO | J = 1.20 μm | H = 1.60 μm | K = 2.20 μm | L = 3.50 μm | Cerro Tololo Inter-American Observatory, a division of NOAO | |||||
Cousins RI photometry | Rc = 647 nm | Ic = 786.5 nm | Cousins RI photometry, 1976[7] | |||||||
DENIS | I = 0.79 μm | J = 1.24 μm | K = 2.16 μm | Deep Near Infrared Survey | ||||||
Eggen RI photometry | Re = 635 nm | Ie = 790 nm | Eggen RI photometry, 1965[8] | |||||||
FIS | N60 = 65.00 μm | WIDE-S = 90.00 μm | WIDE-L = 145.00 μm | N160 = 160.00 μm | Far-Infrared Surveyor on board, AKARI space telescope | |||||
GALEX | NUV = 1800-2750Å | FUV = 1400-1700Å | GALaxy Evolution Explorer | |||||||
GOODS (Hubble ACS) | B = 435 nm | V = 606 nm | i = 775 nm | z = 850 nm | Advanced Camera for Surveys on the Hubble Space Telescope | |||||
HAWC | Band 1 = 53 µm | Band 2 = 88 µm | Band 3 = 155 µm | Band 4 = 215 µm | High-resolution Airborne Wideband Camera for SOFIA[9] | |||||
HDF | 450 nm | 606 nm | 814 nm | 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[10] |
ISAAC UTI/VLT[11] | Js = 1.2 µm | H = 1.6 µm | Ks = 2.2 µm | L = 3.78 µm | Brα = 4.07 µm | Infrared Spectrometer And Array Camera at Very Large Telescope | ||||
Johnson system (UBV) | U = 364 nm | B = 442 nm | V = 540 nm | UBV photometric system | ||||||
OMC | Johnson V-filter = 500-580 nm | Optical Monitor Camera[12] on INTEGRAL | ||||||||
Pan-STARRS | uses the Sloan's g,r,i,z filters plus y = 1005 nm | Panoramic Survey Telescope And Rapid Response System | ||||||||
ProNaOS/SPM | Band 1 = 180-240 µm | Band 2 = 240-340 µm | Band 3 = 340-540 µm | Band 4 = 540-1200 µm | PROgramme NAtional d'Observations Submillerètrique/Systéme Photométrique Multibande, balloon-borne experiment[13] | |||||
Sloan, SDSS | u' = 354 nm | g' = 475 nm | r' = 622 nm | i' = 763 nm | z' = 905 nm | 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 | Infrared camera on Midcourse Space Experiment[14] | |||
Spitzer IRAC | 3.6 μm | 4.5 μm | 5.8 μm | 8.0 μm | Infrared Array Camera on Spitzer Space Telescope | |||||
Spitzer MIPS | 24 μm | 70 μm | 160 μm | Multiband Imaging Photometer for Spitzer on Spitzer | ||||||
Stromvil filters | U = 345 nm | P = 374 nm | S = 405 nm | Y = 466 nm | Z = 516 nm | V = 544 nm | S = 656 nm | Stromvil photometry | ||
Strömgren filters | u = 350 nm | v = 411 nm | b = 467 nm | y = 547 nm | β narrow = 485.8 nm | β wide = 485 nm | Strömgren photometric system | |||
UKIDSS (WFCAM) | Z = 882 nm | Y = 1031 nm | J = 1248 nm | H = 1631 nm | K = 2201 nm | UKIRT Infrared Deep Sky Survey | ||||
Vilnius photometric system | U = 345 nm | P = 374 nm | X = 405 nm | Y = 466 nm | Z = 516 nm | V = 544 nm | S = 656 nm | 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 | Visible & Infrared Survey Telescope for Astronomy | |||
WISE | 3.4 μm | 4.6 μm | 12 μm | 22 μm | Wide-field Infrared Survey Explorer | |||||
XMM-Newton OM | UVW2 = 212 nm | UVM2 = 231 nm | UVW1 = 291 nm | U = 344 nm | B = 450 nm | V = 543 nm | XMM-Newton Optical/UV Monitoring[15] | |||
XEST Survey | UVW2 = 212 nm | UVM2 = 231 nm | UVW1 = 291 nm | U = 344 nm | B = 450 nm | 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[16] |
See also
References
- ↑ Spectral Colors
- 1 2 Binney, J.; Merrifield M. Galactic Astronomy, Princeton University Press, 1998, ch. 2.3.2, pp. 53
- ↑ Gouda, N.; N. Gouda; T. Yano; Y. Kobayashi; et al. (23 May 2005). "JASMINE: Japan Astrometry Satellite Mission for INfrared Exploration". Proceedings of the International Astronomical Union. 2004 (IAUC196): 455–468. doi:10.1017/S1743921305001614.
- 1 2 Handbook of Geophysics and the Space Environment 1985, Air Force Geophysics Laboratory, 1985, ed. Adolph S. Jursa, Ch. 25, Table 25-1
- ↑ Monson, Andrew J.; Pierce, Michael J. (2011). "Near-Infrared (Jhk) Photometry of 131 Northern Galactic Classical Cepheids". The Astrophysical Journal Supplement Series. 193: 12. doi:10.1088/0067-0049/193/1/12. Example of use of J for "near-infrared"
- ↑ 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
- ↑ ADPS
- ↑ ADPS
- ↑ HAWC
- ↑ NSFCAM
- ↑ "ISAAC Overview". Paranal Instrumentation. ESO. Retrieved 13 October 2011.
- ↑ About INTEGRAL
- ↑ Calibration of the PRONAOS/SPM submillimeter photometer, F.Pajot et al. 2006
- ↑ MSXPSC – Midcourse Space Experiment (MSX) Point Source Catalog, V2.3
- ↑ XMM-Newton SAS: Watchout Page
- ↑ The XMM-Newton Optical Monitor Survey of the Taurus Molecular Cloud, M.Audard et al. 2006
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
- The Asiago Database on Photometric Systems
- Michael S. Bessell (2005), STANDARD PHOTOMETRIC SYSTEMS, Annual Review of Astronomy and Astrophysics vol. 43, pp. 293–336
- Infrared portrait of the nearby massive star-forming region IRAS 09002-4732, Apai, D.; Linz, H.; Henning, Th.; Stecklum, B., 2005