As part of a program of high spatial resolution imaging of gravitationally lensed sources in the visible and IR, images of 2237 + 030 were obtained in the Gunn r and infrared J, H, K, and 3.3 micron filters. The results of the photometry of the four bright quasar components provide evidence of extinction through the lens and a determination of the extinction law in the galaxy is made. The energy distribution shows evidence of a sharp decrease of the spectral index at wavelengths longer than a rest wavelength of 1 micron. Assuming that microlensing amplification in the IR is of similar strength as in the visible, the data constrain the suggested microlensing event of August-September 1988 to a time scale of 100 days.

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This article may also be accessed on the publisher's website at: http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1991ApJ...376..430N&data_type=PDF_HIGH&type=PRINTER&filetype=.pdf The authors would like to thank the staff of the Canada-France-Hawaii Telescope, in particular Bill Cruise, Ken Barton, and John Hamilton, for their assistance with the observations. The infrared observations would not have been possible without the strong support of the director, Robert McLaren, whome we gratefully thank. We also thank H. Grondines and M. Riopel for help with the data reduction, and M. Langlois for the artwork. D.N. and H.C.K.Y. are supported through the Natural Science and Engineering Research Council by University Research Fellowships and operating grants. W.J.F., J.D.G., Z.N., and J.L.P. were supported by grants from the NSF, NASA-Ames, the National Geographic Society, and NASA.ISSN:1538-4365 Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in February 2014.

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Department, Program, or Center

Chester F. Carlson Center for Imaging Science (COS)


RIT – Main Campus