The first paper features the results of a study led by graduate student Romain Laugier who’s successfully adapted an angular differential observing technique commonly used in high-contrast imaging to the kernel-phase scenario. This approach, coined angular differential kernel-phase (ADK) takes advantage of the sky rotation experienced by the SCExAO instrument at the Nasmyth focus of the Subaru Telescope when the field rotator is turned off. The technique makes it possible to better calibrate the biasing effect introduced by AO-residuals in the presence of quasi-static aberrations. Whereas interferometric observations typically require to alternate between a target of interest and a calibration star, this new approach spends 100% of the observing time on the target of interest, making it a more efficient alternative.
The second paper features the result of a study led by KERNEL project PI Frantz Martinache. This paper goes back to the roots of kernel-phase. After several years of development of the XARA pipeline carried out in the context of the KERNEL project, it was time to revisit previous analysis results in the light of its latest developments. The paper shows that while overall successful, early uses of kernel-phase were not particularly careful. The paper shows that refined descriptions of the diffractive apertures by instruments leads to a major improvement of the kernel-phase analysis and reduces the importance of systematic errors.
Using these new aperture modeling prescriptions, the authors then reprocess previously published observations from ground-based and space-borne observatories and shows major improvements in both cases!
In the same vein as the ADK idea at the core of the Laugier et al (2020) publication, the paper quickly explores the possibility offered by consecutive observations at multiple wavelengths. For a target whose aspect would change depending on the wavelength, spectral differential kernel-phase (SDK?) would be a powerful observing mode that would spend
In this new publication using the tools developed in the context of the KERNEL project, ANU-based PhD student Jens Kammerer announces the detection of eight low-mass companions to stars observed using VLT/NACO in the L-band, five of which were previously unknown,
Among these new companions, two appear at angular separations ranging between 0.8 and 1.2 λ/D (i.e. 80 and 110mas), demonstrating that from the ground, kernel-phase makes it possible to achieve a resolution better than the traditionally accepted diffraction limit of a telescope.
Congratulations to Jens whose paper was accepted for publication by the Monthly Notices of the Royal Astronomical Society (MNRAS) and should appear in the June 2019 edition of the journal! The preprint version of the paper is already available for download on the arXiv.org website: https://arxiv.org/abs/1903.11252
Back in November last year, the concept of kernel-nuller was featured as one of the ten projects selected by the SATT Sud-Est in the context of the innovation challenge called “My Innovation Is…”. Yesterday, the following video was posted on youtube… enjoy!
The following text was extracted from the description of the video (available here):
SATT Sud-Est and its partners present the Superheroes of Innovation, winners of the My innovation is… 2018 competition. During the third edition of the “My Innovation Is…” competition, held on November 27, 2018 at the Palais des Papes in Avignon, France, 10 researchers and future startuppers from the public laboratories of the South & Corsica Regions presented their innovative projects before a jury of experts.
Ignacio CASUSO, Inserm, is able to visualize the nervous system at the molecular level. Sébastien GIRAUD (Aix-Marseille Université) is able to evaluate proprioception to better communicate with our body. Olivier CHUZEL of Aix-Marseille Université has the power to selectively kill cancer cells. Soraya MEZOUAR (Aix-Marseille University) is developing a new therapy using placental stem cells. Eric LECHEVALLIER (AP-HM) can describe and quantify the intensity of a bleed using a connected tool. Manuel ESPINOSA of the University of Corsica controls the storage of solar energy. Christine CONTINO-PEPIN from Avignon Université is able to extract and stabilize compounds of plant origin in an eco-compatible way. Michel Alain BARTOLI (AP-HM) is developing a stent graft dedicated to the endovascular treatment of aortic diseases. Mikaël CHELLI of the Centre Hospitalier Universitaire de Nice masters medical statistics thanks to an autonomous application. Frantz MARTINACHE (Observatoire de la Côte d’Azur) reveals the presence of extrasolar planets in search of habitable worlds. Faced with a merciless jury, they had to fight to convince and ensure the next generation of innovation.
It’s not every day you are called a “super-hero” of innovation 😉
Romain Laugier, PhD student contributing to the KERNEL project, saw his first paper accepted by the journal Astronomy & Astrophysics. The paper shows how images affected by some amount of saturation can be salvaged to make them kernel-compatible again.
Using an archival HST/NICMOS dataset from 1997, Romain was able to show on a known low-mass binary that the recovery algorithm is effective. The signature of the 4.36 magnitude contrast companion, invisible in the original image, is present in the kernel-phase extracted from that image. This kernel-signature was used to constrain the position and contrast of the companion.
This new resolved observation of the low mass companion to Gl 494 along with other recently published images, combined with a long series of archival radial velocity observations by two instruments, lead to very strong constraints on the orbital elements, and ultimately, the dynamical masses of this binary object.
Congratulations to Romain for successfully bringing this paper to the finish line: may this be the first of many others to come! The preprint version of the paper is available for download on the arXiv.org website: http://arxiv.org/abs/1901.02824
A few months ago, I heard about an innovation contest organized by SATT Sud-Est, a company that attempts to facilitate the transfer of technology from laboratories to the industry. The application process looked simple enough so I gave it a shot. It turns out that my application: basically a pitch for robust high-contrast instrumentation (aka a kernel-nuller), was among the ten selected for a live oratory contest that was held just a few days ago, in the city of Avignon inside the famous “Palais des Papes“.
Without direct industrial prospect for the kernel-nuller, it is no surprise that my pitch was not selected as the final winner. The awards went to Dr. Christine Contino-Pepin and Pr. Michel Alain Bartoli who will I have no doubt, be able to turn their ideas into profitable businesses!
Nevertheless, this was a lovely evening, and according to the feedback I received during the networking event that followed, attendees were quite intrigued and enthusiastic about the project. This is the real magic of astronomy in general and of extrasolar planets in particular that still manage to trigger people’s imagination. Even if science in general isn’t the most popular topic of conversation out there, public conferences about astronomy still manage to draw reasonably large and passionate crowds! If only we could trigger the same kind of amazement for all of the other sciences, the world would certainly be a better place!
The KERNEL project, hosted by Observatoire de la Cote d’Azur (OCA) invites applications for a PhD project in the field of high-angular resolution astronomy. This position is funded by the European Research Council (ERC – CoG – grand agreement #683029) under the European Union’s Horizon 2020 research and innovation program. The add was also posted on EURAXESS.
The adaptive optics revolution
Adaptive Optics (AO) has changed the face of observational astronomy, making ground based telescope able to live up to their angular resolution potential, and allowing us to dream up the upcoming generation of large 30m-class giant segmented mirror telescopes (GSMTs). Yet despite its incredible achievements, AO still hasn’t fully succeded in bringing the quality of astronomical images to its full potential, required for modern observing techniques such as high-contrast imaging and/or coupling into single mode fibers, enabling the use of photonic technology.
Objectives of the PhD project
The next major breakthrough will come from using information of great
value, available in the focal plane, to directly to drive AO systems.
Such an approach is finally possible today, thanks to the availability
of high-cadence, low readout noise near-infrared detectors and that of
enhanced real time computing capabilities. Observatoire de la Côte
d’Azur (OCA) and the Subaru Telescope are teaming up to offer a PhD
project that will turn this ambitious goal into a reality. This PhD is
funded by the KERNEL project. It will be co-supervised by the KERNEL
project PI F. Martinache (OCA) and the Subaru Coronagraphic Extreme AO
(SCExAO) project lead O. Guyon (Subaru Telescope).
The successful applicant will benefit from state of the art hardware and expertise along with access to two complementary experimental setups, both taking advantage of the same software environment:
the KERNEL test-bench, located in Nice (France), with a unique multi-wavelength capability, and a segmented deformable provides the means to prototype applications for GSMTs and long baseline interferometry developments.
the SCExAO instrument itself, installed at the Nasmyth focus of the Subaru Telescope, located atop Mauna Kea (Hawaii USA), provides the means to validate strategies using unique on-sky validation capability and have a rapid impact on the community.
The PhD should preferably start in the Fall 2018. To apply, the candidate is required to send (email firstname.lastname@example.org) a copy of his vita, and a letter detailing his/her interest in the project along with a transcript of his/her master degree in physics, astronomy or a relevant engineering specialty. The candidate should be willing to work as part of a team, to collaborate with an international network of people involved with a wide variety of activities: data processing, astrophysical modeling, observing at the telescope, experimentation in optics and real-time computing.
Astronomy and Instrumentation by Frantz Martinache