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arXiv · 2603.03448

Updating the Sensitivity Curves of the STIS Echelles (Post-SM4)

Svea Hernandez·TalaWanda Monroe·Joleen K. Carlberg
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Abstract

The STIS team re-derived on-orbit sensitivity curves for the echelle modes for post-servicing mission 4 observations using the standard DA white dwarf G 191-B2B. These new updates relied on the recent CALSPECv11 models, which introduced improvements in the fluxes of the primary standard stars of the order of~1-3% depending on the wavelength of interest. As part of this effort, the team also released new blaze shift coefficients and echelle ripple tables. We present a detailed description of the procedures followed in the derivation of these new throughputs and the accompanying updates.

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Svea Hernandez, TalaWanda Monroe, Joleen K. Carlberg. 2026-03-03. Updating the Sensitivity Curves of the STIS Echelles (Post-SM4). https://arxiv.org/abs/2603.03448

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