The textit{JWST} Early Release Science Program for Direct Observations of Exoplanetary Systems III: Aperture Masking Interferometric Observations of the star HIP,65426 at $boldsymbol{3.8,rm{μm}}$

Kavli Affiliate: Bruce Macintosh

| First 5 Authors: Shrishmoy Ray, Steph Sallum, Sasha Hinkley, Anand Sivamarakrishnan, Rachel Cooper

| Summary:

We present aperture masking interferometry (AMI) observations of the star HIP
65426 at $3.8,rm{mu m}$ as a part of the textit{JWST} Direct Imaging Early
Release Science (ERS) program obtained using the Near Infrared Imager and
Slitless Spectrograph (NIRISS) instrument. This mode provides access to very
small inner working angles (even separations slightly below the Michelson limit
of ${}0.5lambda/D$ for an interferometer), which are inaccessible with the
classical inner working angles of the textit{JWST} coronagraphs. When combined
with textit{JWST}’s unprecedented infrared sensitivity, this mode has the
potential to probe a new portion of parameter space across a wide array of
astronomical observations. Using this mode, we are able to achieve a contrast
of $Delta m_{F380M}{sim }7.8$,mag relative to the host star at a separation
of ${sim}0.07arcsec$ but detect no additional companions interior to the
known companion HIP,65426,b. Our observations thus rule out companions more
massive than $10{-}12,rm{Mtextsubscript{Jup}}$ at separations
${sim}10{-}20,rm{au}$ from HIP,65426, a region out of reach of ground or
space-based coronagraphic imaging. These observations confirm that the AMI mode
on textit{JWST} is sensitive to planetary mass companions orbiting at the
water frost line, even for more distant stars at $sim$100,pc. This result
will allow the planning and successful execution of future observations to
probe the inner regions of nearby stellar systems, opening essentially
unexplored parameter space.

| Search Query: ArXiv Query: search_query=au:”Bruce Macintosh”&id_list=&start=0&max_results=3

Read More