The UBViyz photometric system
Basic Reference
Jennens P.A., Helfer H.L. 1975, Mon. Not. R. Astr. Soc. 172, 667
Abstract
Photometry of 260 G and K giants, using a fast broad-intermediate band
photometric system (UBViyz system) is used to calibrate chemical composition,
[Fe/H], luminosity, Mv and colour excess, E(B-V). A simple S-20 surface
photomultiplier is used. The UBVi photometry is transformed to be on the
Johnson UBVRI system.
Calibrations applicable to the ranges 0.40 < R-I < 0.65
(G2-K3), 0.65 < R-I < 0.90 (K3-K5) are given. A photometric luminosity index,
Mv(yz), is derived for which rms errors are +- 1 mag. Several indices are
calibrated for chemical composition, [Fe/H], and typical rms errors of +- 0.15
in [Fe/H] are obtained for stars of known colour excess, E(B-V). For stars of
unknown colour excess, E(B-V) is determined with an rms error of +- 0.06 and
[Fe/H] with an rms error of ~+- 0.4. For stars with Mv < -1, the errors are
larger.
Content
Access to the data and references
Asiago Database on Photometric System (ADPS)
Indices and Parameters
V, U-B, B-V, Y-V, Y-Z, V-i
Filters
- U : Corning 9863 + CuSO4
- Lam_eff : 3660 Å ; Width : 600 Å
- B : Corning 5030 + 1 mm Schott 9913 + CuSO4
- Lam_eff : 4400 Å ; Width : 900 Å
- V : Corning 3384 + 1.6 mm Schott BG18
- Lam_eff : 4930 Å ; Width : 700 Å
- i : 3 mm D RG 780
- Lam_eff : 7900 Å ; Width : 600 Å
- y : Baird Atomic 12-39-5
- Lam_eff : 4600 Å ; Width : 200 Å
- z : Baird Atomic 14-74-4
- Lam_eff : 5160 Å ; Width : 200 Å
Photomultiplier
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commentsto epaunzen@physics.muni.cz
epaunzen@physics.muni.cz
Last update: 13 September 2002