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arXiv · 0909.3878

Far-UV sensitivity of the Cosmic Origins Spectrograph

Stephan R. McCandliss·Kevin France·Steven Osterman·James C. Green·Jason B. McPhate·Erik Wilkinson
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Abstract

We demonstrate that the G140L segment B channel of the Cosmic Origins Spectrograph (COS) recently installed on the {\it Hubble Space Telescope (HST)} has an effective area consistent with $\sim$ 10 cm$^2$ in the bandpass between the Lyman edge at 912 Åand Lyman $β$, rising to a peak in excess of 1000 cm$^2$ longward of 1130 Å. This is a new wavelength regime for {\it HST} and will allow opportunities for unique science investigations. In particular, investigations seeking to quantify the escape fraction of Lyman continuum photons from galaxies at low redshift, determine the scale-length of the hardness variation in the metagalactic ionizing background over the redshift range 2 $< z \lesssim$ 2.8, measure the ratio of CO to H$_2$ in dense interstellar environments with $A_V >$ 3, or harness the high temperature diagnostic power of the \ion{O}{6} $λλ$ 1032, 1038 doublet can now be carried out with unprecedented sensitivity.

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Stephan R. McCandliss, Kevin France, Steven Osterman, James C. Green, Jason B. McPhate, Erik Wilkinson. 2009-09-21. Far-UV sensitivity of the Cosmic Origins Spectrograph. https://doi.org/10.1088/2041-8205%2F709%2F2%2Fl183

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