Mid-Infrared Interferometry of Circumstellar Envelopes Around Galactic Cepheids
The first comprehensive mid-infrared long-baseline interferometric survey (VLTI/MATISSE, L/M/N bands) of eight Galactic Cepheids spanning the instability strip (pulsation periods 7-38 days). Combining SED analysis, closure phases and visibilities with SPIPS-predicted angular diameters and DUSTY radiative-transfer test cases, it finds no resolved circumstellar dust signature, sets 2-sigma upper limits on circumstellar-envelope flux (excluding models with R_CSE~10 R_star and f_CSE~10%), and provides direct evidence that circumstellar dust emission is negligible or absent across a wide range of Cepheid parameters.
Circumstellar emission of Cepheids across the instability strip: Mid-infrared observations with
The circumstellar envelopes (CSE) of Cepheids are still not well characterized despite their potential impact on distance determination via both the period-luminosity relation and the parallax-of-pul…