The TR-74Ui-H Illuminance UV Recorder from TandD Corporation (Saratoga Springs, NY) can simultaneously measure and record four parameters: illuminance, ultraviolet light (UV), temperature, and humidity.
Photo-dissociation regions at the edge of molecular clouds illuminated by bright stars are unique targets for the study of the interaction of stellar ultraviolet radiation with dense gas.
Density structure of the Horsehead nebula photo-dissociation region
Most of the optical and ultraviolet luminosity (Lopt ∼ Lultraviolet ∼ 10−2LX ) likely comes from the accretion ﬂow as it is illuminated by the X-rays from the neutron star.
Simultaneous ASCA and HST/GHRS observations of Cygnus X-2/V1341 Cygni
The pro jector ﬂats provide illumination in the ultraviolet end of the CCD (λ < 3800 ˚A), the dome ﬂats at redder wavelengths, and the sky ﬂat permitted us to correct the dome and pro jector ﬂats for uneven illumination along the slit.
An Atlas of Spectrophotometric Landolt Standard Stars
However, photoexcitation of the 23S1 level to the 23P term may not be negligible for photoionized plasmas illuminated by intense ultraviolet radiation (Porquet et al. 2001b and references therein).
X- and Gamma-Ray Line Emission Processes
Ultraviolet photons with energies above 11 eV can photodissociate H2, and this can suppress the cooling rate and the ability to form stars in low-mass halos that are cooling by H2 when they are illuminated by the first stars (38).
The Dark Age of the Universe